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Antibody-drug conjugates (ADCs) represent a promising cancer therapy modality which specifically delivers highly toxic payloads to cancer cells through antigen-specific monoclonal antibodies (mAbs). To date, 15 ADCs have been approved and more than 100 ADC candidates have advanced to clinical trials for the treatment of various cancers. Among these ADCs, microtubule-targeting and DNA-damaging agents are at the forefront of payload development. However, several challenges including toxicity and drug resistance limit the potential of this modality. To tackle these issues, multiple innovative payloads such as immunomodulators and proteolysis targeting chimeras (PROTACs) are incorporated into ADCs to enable multimodal cancer therapy. In this review, we describe the mechanism of ADCs, highlight the importance of ADC payloads and summarize recent progresses of conventional and unconventional ADC payloads, trying to provide an insight into payload diversification as a key step in future ADC development.
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Imunoconjugados , Neoplasias , Humanos , Imunoconjugados/farmacologia , Imunoconjugados/uso terapêutico , Imunoconjugados/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , AnimaisRESUMO
Cotton is one of the oldest and most widely used natural fibers in the world. It enables a wide range of applications due to its excellent moisture absorption, thermal insulation, heat resistance, and durability. Benefiting from current developments in textile technology and materials science, people are constantly seeking more comfortable, more beautiful and more versatile cotton fabrics. As the second skin of body, clothing not only provides the basic needs of wear but also increases the protection of body against different environmental stimuli. In this article, a comprehensive review is proposed regarding research activities of systematically summarise the development and research of cotton fabric-based photocatalytic composites for the degradation of organic contaminants in the area of self-cleaning, degradation of gaseous contaminants, pathogenic bacteria or viruses, and chemical warfare agents. Specifically, we begin with a brief exposition of the background and significance of cotton fabric-based photocatalytic composites. Next, a systematical review on cotton fabric-based photocatalytic composites is provided according to their mechanisms and advanced applications. Finally, a simple summary and analysis concludes the current limitations and future directions in these composites for the degradation of organic contaminants.
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While polyethylene terephthalate (PET) has enjoyed widespread use, a large volume of plastic waste has also been produced as a result, which is detrimental to the environment. Traditional treatment of plastic waste, such as landfilling and incinerating waste, causes environmental pollution and poses risks to public health. Recycling PET waste into useful chemicals or upcycling the waste into high value-added materials can be remedies. This review first provides a brief introduction of the synthesis, structure, properties, and applications of virgin PET. Then the conversion process of waste PET into high value-added materials for different applications are introduced. The conversion mechanisms (including degradation, recycling and upcycling) are detailed. The advanced applications of these upgraded materials in energy storage devices (supercapacitors, lithium-ion batteries, and microbial fuel cells), and for water treatment (to remove dyes, heavy metals, and antibiotics), environmental remediation (for air filtration, CO2 adsorption, and oil removal) and catalysis (to produce H2, photoreduce CO2, and remove toxic chemicals) are discussed at length. In general, this review details the exploration of advanced technologies for the transformation of waste PET into nanostructured materials for various applications, and provides insights into the role of high value-added waste products in sustainability and economic development.
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Recuperação e Remediação Ambiental , Nanoestruturas , Polietilenotereftalatos/química , Dióxido de Carbono , Reciclagem , Plásticos/químicaRESUMO
BACKGROUND AND AIMS: Limited evidence exists on the prognostic outcomes of the blood urea nitrogen to serum albumin ratio (B/A ratio) in congestive heart failure (CHF), particularly in developing countries with scarce heart failure epidemiological data. We aimed to investigate the association between B/A ratio and short-term outcomes in Chinese patients with CHF. METHODS AND RESULTS: We included 1761 CHF patients with available B/A ratio data from a cohort of 2008 patients. Patients were categorized into three groups based on B/A ratio (low to high). The primary endpoint was death or readmission within 28 days, and the secondary endpoint was death or readmission within 90 days. We employed restricted cubic spline analysis, Cox proportional hazards regression, and Kaplan-Meier curves to evaluate the relationship between B/A ratio at admission and the endpoints. Even after adjusting for other variables, higher B/A ratios were associated with increased rates of 28 days and 90 days mortality or readmission (HR: 2.4, 95% CI: 1.81-3.18 and HR: 1.74, 95% CI: 1.48-2.05). Significant differences in the risks of both primary and secondary endpoints were observed among the three B/A ratio groups. The association between B/A ratio and CHF was stable in the different subgroups (all P for interactionï¼0.05). CONCLUSION: Higher B/A ratios are associated with an increased risk of short-term mortality or readmission in Chinese patients with CHF. The B/A ratio shows promise as a prognostic indicator for short-term outcomes in CHF patients.
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Nitrogênio da Ureia Sanguínea , Albumina Sérica , Albumina Sérica/análise , China , Estudos Retrospectivos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Valor Preditivo dos Testes , Estudos de Coortes , Humanos , Masculino , Feminino , IdosoRESUMO
OBJECTIVE: To quantify the results of superficial parotidectomy (SP) and partial SP (PSP) for benign parotid tumours using a systematic evaluation method. METHODS: A systematic search of English and Chinese databases (PubMed, Web of Science, Cochrane Library, China Knowledge Network, Wanfang and Vipshop) was conducted to include studies comparing the treatment outcomes of SP with PSP. RESULTS: Twenty-three qualified, high-quality studies involving 2844 patients were included in this study. The results of this study showed that compared to the SP surgical approach, the PSP surgical approach reduced the occurrence of temporary facial palsy (OR = 0.33; 95% confidence interval [CI] 0.26-0.41), permanent facial palsy (OR = 0.28; 95% CI 0.16-0.52) and Frey syndrome (OR = 0.36; 95% CI 0.23-0.56) in patients after surgery, and the surgery operative time was reduced by approximately 27.35 min (95% CI - 39.66, - 15.04). However, the effects of PSP versus SP on salivary fistula (OR = 0.70; 95% CI 0.40-1.24), sialocele (OR = 1.48; 95% CI 0.78-2.83), haematoma (OR = 0.34; 95% CI 0.11-1.01) and tumour recurrence rate (OR = 1.41; 95% CI 0.48-4.20) were not statistically significant. CONCLUSION: Compared with SP, PSP has a lower postoperative complication rate and significantly shorter operative time, suggesting that it could be used as an alternative to SP in the treatment of benign parotid tumours with the right indications.
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Paralisia Facial , Neoplasias Parotídeas , Humanos , Paralisia Facial/etiologia , Paralisia Facial/prevenção & controle , Glândula Parótida/cirurgia , Neoplasias Parotídeas/cirurgia , Neoplasias Parotídeas/patologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/patologia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
BACKGROUND/OBJECTIVES: Tibetan tea is a kind of dark tea, due to the inherent complexity of natural products, the chemical composition and beneficial effects of Tibetan tea are not fully understood. The objective of this study was to unravel the composition of Tibetan tea using knowledge-guided multilayer network (KGMN) techniques and explore its potential antioxidant and hypolipidemic mechanisms in mice. MATERIALS/METHODS: The C57BL/6J mice were continuously gavaged with Tibetan tea extract (T group), green tea extract (G group) and ddH2O (H group) for 15 days. The activity of total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) in mice was detected. Transcriptome sequencing technology was used to investigate the molecular mechanisms underlying the antioxidant and lipid-lowering effects of Tibetan tea in mice. Furthermore, the expression levels of liver antioxidant and lipid metabolism related genes in various groups were detected by the real-time quantitative polymerase chain reaction (qPCR) method. RESULTS: The results showed that a total of 42 flavonoids are provisionally annotated in Tibetan tea using KGMN strategies. Tibetan tea significantly reduced body weight gain and increased T-AOC and SOD activities in mice compared with the H group. Based on the results of transcriptome and qPCR, it was confirmed that Tibetan tea could play a key role in antioxidant and lipid lowering by regulating oxidative stress and lipid metabolism related pathways such as insulin resistance, P53 signaling pathway, insulin signaling pathway, fatty acid elongation and fatty acid metabolism. CONCLUSIONS: This study was the first to use computational tools to deeply explore the composition of Tibetan tea and revealed its potential antioxidant and hypolipidemic mechanisms, and it provides new insights into the composition and bioactivity of Tibetan tea.
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ARX788 is an anti-human epidermal growth factor receptor 2 (HER2) antibody-drug conjugate with AS269 as cytotoxic payload. In this phase 1 multicenter dose-expansion clinical trial, patients with HER2-positive advanced gastric/gastroesophageal junction adenocarcinoma failing to respond to prior trastuzumab-based standard treatment were enrolled. Between July 15th, 2019, and March 14th, 2022, 30 participants were enrolled. Twenty-eight (93.3%) patients experienced at least one drug-related adverse event (AE) and 13.3% experienced grade 3 ARX788-related AEs. The confirmed objective response rate is 37.9% (95% confidence interval [CI]: 20.7%-57.7%) and the disease control rate is 55.2% (95% CI: 35.7%-73.6%). With a median follow up of 10 months, the median progression-free survival and overall survival are 4.1 (95% CI: 1.4-6.4) and 10.7 months (95% CI: 4.8-not reached), respectively. The median duration of response is 8.4 (95% CI: 2.1-18.9) months. ARX788 is well tolerated and has promising anti-tumor activity in patients with HER2-positive advanced gastric adenocarcinoma (ChinaDrugTrials.org.cn: CTR20190639).
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Adenocarcinoma , Neoplasias Esofágicas , Humanos , Neoplasias Esofágicas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Junção Esofagogástrica/patologiaRESUMO
Functional textiles with advanced moisture management can enhance human comfort and physiological health. However, conventional wet finishing processes used for textiles are usually highly polluting and exhibit poor fastness. Inspired by the strong underwater adhesion properties of mussels based on cation-π interaction, a novel superhydrophilic polymeric molecule with strong cohesion and adhesion property is designed on a poly(ethylene terephthalate) (PET) fabric. The cation-π hydrophilic agent (CPHA) can efficiently transform the hydrophobic PET fabric to a superhydrophilic one, and its superhydrophilicity can withstand 150 home laundry cycles. In addition, the cationic moieties in the CPHA self-adhere to the PET fabric without any finishing auxiliary that would cause pollution. Due to its strong adhesion, CPHA can be applied to one side of the PET fabric via spray coating and curing to form a Janus hydrophobic/superhydrophilic fabric capable of diode-like one-way sweat transportation (with forward transportation capability of 1115% and backward transportation capability of -1509%). Moreover, the Janus fabric inhibits bacterial growth and invasion, while simultaneously preserving the inner ecological healthy balance of the skin's microflora. This work opens up a pathway to develop adhesives in textile wet processing for more diverse, smarter applications, e.g., quick-dry sportswear, protective suits, or air-conditioning fabrics.
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Têxteis , Interações Hidrofóbicas e Hidrofílicas , Cimentos de ResinaRESUMO
To obtain a wide range of high-precision time-delay controllable devices, a 100-µm-thick nematic liquid crystal (LC) cell was fabricated using the LC HTD028200-200. Factors influencing the delay calibration accuracy of LC variable retarders (LCVRs) were analyzed theoretically and experimentally. Subsequently, within the total voltage tuning range of 0-5 V, the LCVR had a delay of 4.977-97.404 fs, total delay range of 90 fs, tuning accuracy of ±0.216fs, and tuning resolution of 0.128 fs. This device will play an important role in spectral imaging.
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High laser damage threshold optical switches and spatial light modulators are in urgent demand in high power laser fields. In this Letter, liquid crystal optical switches using Si-doped GaN and Mg-doped GaN as transparent electrodes are fabricated, and the influence of the conductive properties of GaN is analyzed. The transmission and absorption characteristics of GaN and its sapphire substrate are tested. The results show that the liquid crystal device based on gallium nitride can be expected to play an important role in the fields of visible and near-infrared laser regions with a high laser damage threshold of more than 1J/cm2.
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Conventional antibody-drug conjugates (ADC) utilize native surface-exposed lysines or cysteines on the antibody of interest to conjugate cytotoxic payload. The nonspecific conjugation results in a mixture with variable drug-to-antibody ratios (DAR), conjugation sites, and ADCs that are often unstable in systemic circulation. ARX788 is an ADC consisting of a HER2-targeting antibody site-specifically conjugated with a potent antitubulin cytotoxic drug-linker, AS269. The site-specific conjugation is achieved by first incorporating the nonnatural amino acid, para-acetyl phenylalanine (pAF), into the antibody, followed by covalent conjugation of AS269 to the pAF to form a highly stable oxime bond resulting in a DAR 2 ADC. ARX788 exhibits significant, dose-dependent antitumor activity against HER2- expressing breast and gastric xenograft tumors. Pharmacokinetic (PK) studies in multiple species showed the highly stable nature of ARX788 with overlapping PK profiles for the intact ADC and total antibody. Metabolism studies demonstrated that pAF-AS269 was the sole major metabolite of ARX788, with no evidence for the release of free drug often observed in conventional ADCs and responsible for adverse side effects. Furthermore, ARX788 demonstrated a favorable safety profile in monkeys with a highest nonseverely toxic dose of 10 mg/kg, which was well above the efficacious dose level observed in preclinical tumor models, thus supporting clinical development of ARX788.
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Anticorpos Monoclonais/administração & dosagem , Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Oligopeptídeos/administração & dosagem , Receptor ErbB-2/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/farmacocinética , Antineoplásicos/química , Antineoplásicos/farmacocinética , Azidas/química , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Feminino , Ferricromo/química , Haplorrinos , Humanos , Masculino , Camundongos , Oligopeptídeos/química , Oligopeptídeos/farmacocinética , Ratos , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Ventral hernia, also known as incisional hernia, is a common complication of previous surgery. The contents of ventral hernia may include omentum, preperitoneal fat, small intestine or colon. However, ventral hernia with protrusion of more than two parenchymal organs simultaneously is extremely rare, and its repair is very complex and difficult. Surgeons should make a comprehensive assessment based on their own experience and the individual characteristics of the hernia. In addition, psychological therapy should be emphasized in the whole treatment process. CASE SUMMARY: We report a rare case of asymptomatic giant ventral hernia for 15 years in a 21-year-old female. The patient underwent umbilical hernia repair at the age of 1 year. Approximately 5 years later, ventral hernia recurred and repair with Mesh was performed, but the operation failed due to postoperative infection, and a huge mass appeared in the left abdominal wall. The mass increased gradually with the development and maturity of the body. Computerized tomography scan demonstrated that the patient's total spleen, part of the pancreas and left lobe of the liver were simultaneously herniated through the abdominal incisional hernia. As the patient was unable to endure the inconvenience of life and the potential risk of spleen or liver rupture, she underwent a ventral hernia repair with Mesh at our hospital. The operation was successful and the patient had a good recovery. During a 3-mo follow-up, the patient remained asymptomatic and the appearance of the surgical incision was greatly improved. CONCLUSION: Ventral hernia is a common complication of abdominal surgery. Ventral hernia with protrusion of more than two parenchymal organs simultaneously is extremely rare. Surgeons should pay attention to the psychological treatment while restoring the abdominal physiological function in ventral hernia patients.
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BACKGROUND: The prognostic nutritional index (PNI), an immunity and nutrition based prognostic score, was correlated with clinical outcomes in different tumors. However, the prognostic significance of PNI has not been investigated in hormone sensitive prostate cancer (PCa). The objective of this study was to determine the prognostic significance of PNI in hormone sensitive PCa. METHODS: Two hundred eighty PCa patients undergoing androgen deprivation therapy (ADT) as first line therapy at three centers were enrolled. The serum albumin levels and peripheral lymphocyte count were measured at the time of diagnosis. PNI was calculated as 10 * serum albumin (g/dL) + 0.005 * total lymphocyte count (per mm3). Patients were categorized in two groups using a cut-off point of 50.2 as calculated by the receiver-operating curve analysis. Univariate and multivariate cox regression analyses were performed to evaluate PNI as a favorable prognostic factor for progression-free survival (PFS), cancer-specific survival (CSS) and overall survival (OS). Prognostic accuracy was evaluated with the Harrell concordance index. RESULTS: Multivariate analyses identified PNI as an independent prognostic indicator with respect to PFS (hazard ratio (HR) = 0.521, p = 0.001), CSS (HR = 0.421, p = 0.002) and OS (HR = 0.429, p = 0.001). Patients with elevated PNI had better clinical outcomes. The addition of PNI to the final models improved predictive accuracy (c-index: 0.758, 0.830 and 0.782) for PFS, CSS and OS compared with the clinicopathological base models (c-index: 0.736, 0.801 and 0.752), which included Gleason score and incidence of metastasis. CONCLUSIONS: Elevated pretreatment PNI was a favorable prognostic indicator for PCa patients treated with ADT.
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Antagonistas de Androgênios/uso terapêutico , Neoplasias Hormônio-Dependentes/metabolismo , Avaliação Nutricional , Estado Nutricional , Neoplasias da Próstata/metabolismo , Adulto , Idoso , Seguimentos , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/mortalidade , Neoplasias Hormônio-Dependentes/patologia , Valor Preditivo dos Testes , Prognóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Estudos Retrospectivos , Albumina Sérica Humana/metabolismo , Taxa de SobrevidaRESUMO
Osteosarcoma (OS) is a common malignant bone tumor, presenting particularly in children and young adults, and accounts for approximately 19% of all malignant bone cancers. Despite advances in OS treatment, longterm prognosis remains poor. miRNAs are noncoding singlestranded RNAs ~22 nucleotides in length. Increasing evidence suggests that numerous miRNAs may play critical roles in tumorigenesis and tumor progression; however, the role of miR95 in OS has not been examined. In the present study, we investigated the role of miR95 in OS using in vitro and in vivo models and publicly available expression data. Our findings indicate that abnormal miR95 expression occurs in OS, according to the Gene Expression Omnibus (GEO) database. The miR95 inhibitor reduced cell proliferation and promoted apoptosis in OS cell lines as detected by EdU staining, TUNEL staining and flow cytometry. Furthermore, a dual luciferase reporter assay revealed that miR95 regulates the cell cycle of OS cells and apoptosis by targeting sodium channel epithelial 1α subunit (SCNN1A). Additionally, miR95 antagomir suppressed the growth of U2OS xenograft tumors in a mouse model. In summary, our results suggest that miR95 induces OS growth in vitro and in vivo by targeting SCNN1A. Our results help clarify the mechanism underlying the miR95mediated effects on OS tumor growth, thus potentially establishing it as a diagnostic target.
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Neoplasias Ósseas/patologia , Canais Epiteliais de Sódio/genética , MicroRNAs/genética , Osteossarcoma/patologia , Regulação para Cima , Animais , Apoptose , Neoplasias Ósseas/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Canais Epiteliais de Sódio/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Transplante de Neoplasias , Osteossarcoma/genética , PrognósticoRESUMO
We study the morphologies of a polyelectrolyte brush grafted onto a surface of cubic geometry under good solvent conditions in the presence of trivalent counterions, using molecular dynamics simulations. The electrostatic correlation effect and excluded volume effect on the morphologies are studied through varying the charge fraction and grafting density, respectively. Combining snapshots of surface morphologies, brush height, distribution profiles of polymer monomers, and monomer-monomer/counterion pair correlation functions, it is clearly shown that the electrostatic correlation effect, represented by the trivalent-counterion-mediated bridging effect, can induce lateral microphase separation of the cubic polyelectrolyte brush, resulting in the formation of pinned patches. These structures then lead to multi-scale ordering in the brush system and, thereby, a non-monotonic dependence of the brush height, corresponding to a collapse-to-swell transition, on the grafting density. Our simulation results demonstrate that, with the sequence of surface morphologies responsive to adjusting external parameters, the cubic polyelectrolyte brush can serve as a candidate system for the manufacturing of smart stimuli-responsive materials.
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In this work, the self-assembly behaviors of diblock copolymers consisting of one hydrophobic block and one ionizable polyelectrolyte (PE) block in the presence of monovalent and multivalent counterions are systematically discussed through molecular dynamics simulation. Copolymers are molded as bead-spring chains and the ions are explicitly considered. First, the self-assembled structures of symmetrical block copolymers at different charge fractions are analyzed in detail. Spherical hydrophobic cores are favored by all of the micelles. The effect of counterion valence is much more noticeable at high values of charge fraction. When the PE blocks are fully charged, the presence of multivalent counterions preferably provokes the formation of macroscopic structures. A precipitant spherical micelle is generated in the presence of divalent counterions. Special shapes of coronas are created in the presence of trivalent ions, and a remarkable one dimensional macroscopic cylindrical aggregation of micelles forms; the whole assembly is not typical core-shell micelles, but rather a cylinder with alternating spherical micelles arranged perpendicular to the cylinder axis. The self-assemblies with different lengths of fully charged PE blocks are also discussed. Surprisingly, in the presence of divalent counterions, two dimensional in-plane macroscopic aggregation of micelles is realized when the proportion of PE blocks is larger than 1/2; the self-assembled spherical micelles locate approximately in the same plane to form an inter-linked network. One dimensional aggregation of micelles in the presence of trivalent counterions is maintained with an increased proportion of the PE block. Owing to the dominant intra- and inter-condensation of divalent and trivalent counterions, respectively, two and one dimensional macroscopic aggregation of the micelles is achieved. Our findings indicate that varying the counterion valence is a powerful mechanism to tune the properties of self-assemblies, and the bridging effect introduced by multivalent counterions is the key parameter for the aggregation of the micelles.
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In order to suppress the frequency modulation to amplitude modulation (FM-to-AM) conversion induced by a Nd:glass regenerative laser amplifier, a birefringent quartz crystal was designed by theoretical simulation and inserted into the regenerative amplifier. A broadband Nd:glass regenerative laser amplifier with a flattop region of â¼3.7 nm in the gain spectrum was developed. An all-fiber front-end system was used to generate a 2 ns shaped pulse with a spectral width of â¼0.5 nm, which was broadened by a two-stage phase modulator. Then, the laser pulse was amplified by a spectral-broadened regenerative amplifier. The amplified output temporal waveform modulation depth was reduced from a maximum of 47.7% to 17.3% at a center wavelength of 1053.328 nm. The experimental results show that the FM-to-AM conversion can be effectively suppressed in the spectral-broadened Nd:glass regenerative laser amplifier, which indicates that it has potential application as a preamplifier of large-scale laser facilities.
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We report a case of intermittent lower abdominal pain and distension accompanied by defecation difficulties for 3 years due to Chilaiditi syndrome in a 59-year-old male. Before admission to our hospital, the patient had undergone gastroscopy, which showed gastritis and duodenitis, and colonoscopy, which showed cecum deformation and cicatricial changes of the mucous membrane in the colon hepatic flexure. A computed tomography (CT) scan of the abdomen at our hospital confirmed right hepatic atrophy and interposition of the colon. Moreover, CT simulation endoscopy identified cystic dilatation in the colon hepatic flexure with the widest diameter of 8.2 cm. The patient was diagnosed with Chilaiditi syndrome. As the patient was unable to endure his defecation difficulties, he underwent a laparoscope-assisted right hemicolectomy. The patient had a good recovery. During the follow-up period of 9 mo, the patient remained symptom-free.
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The surface morphologies of spherical polyelectrolyte brushes in salt solutions with opposite trivalent ions are studied using molecular dynamics (MD) simulations. The impact of salt concentration, grafting density, and charge fraction on brush morphologies is investigated systematically. A variety of surface patterns are predicted and the phase diagrams are presented. Both lateral and radial microphase separated structures in the brushes are observed upon varying the salt concentration. With low grafting density the spherical brush is separated into several patches, the number of which decreases with the addition of salt. At high grafting density, the polymer brush changes its morphology from an extended micelle to a 'carpet + brush' to the collapsed state upon increasing the salt concentration. Especially, the 'carpet + brush' structure consists of a core formed by partially collapsed brush chains and a corona formed by other stretched chains. The inter-chain 'bridging' interactions mediated by trivalent ions and the curvature effect play important roles in determining the chain conformations and brush structures.
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The temporal contrast levels of laser pulses in the injection laser system of the Shenguang-II facility are accurately measured and analyzed in detail. These signal-to-noise ratio levels are determined by the extinction ratios of an acousto-optic modulator, an electro-optic intensity modulator, and a combination of a Pockels cell and thin film polarizers. In addition, a drifting direct current bias voltage of an electro-optic intensity modulator and phase modulation are also demonstrated to affect the signal-to-noise ratio of the injection laser system. With a precise control of these factors, the injection laser system can output a nanosecond laser pulse with a signal-to-noise ratio of 47.37 dB. Moreover, a nanosecond laser pulse signal-to-noise ratio measuring device with a dynamic range and accuracy of 50 and 1 dB, respectively, is developed to detect the signal-to-noise ratio of a nanosecond laser pulse, which is 47.06 dB within an accuracy range of 1 dB. The signal-to-noise ratio measuring device can detect the high contrast laser pulse for the seed source unit in the high power laser facility accurately and conveniently.