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A Si-based nanowire array photonic-crystal surface-emitting laser based on a flat band is designed and simulated. By introducing an air gap between the nanowire and substrate, the bottom reflectivity is significantly enhanced, resulting in much lower threshold and smaller cutoff diameter. Through adjusting the lattice constant (the distance between neighboring nanowires) and nanowire diameter, a photonic crystal structure with a flat band is achieved, in which strong interaction between light and matter occurs in the flat band mode. For the device with a small size, single-mode lasing is obtained with a side-mode suppression ratio of 21â dB, high quality factor of 3940, low threshold gain of 624â cm-1, and small beam divergency angle of â¼7.5°. This work may pave the way for the development of high-performance Si-based surface-emitting nanolasers and high-density photonic integrated circuits.
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A topological photonic crystal InGaAsP/InP core-shell nanowire array laser with bulk states operating in the 1550â nm band is proposed and simulated. By optimizing the structure parameters, high Q factor of 1.2 × 105 and side-mode suppression ratio of 13.2â dB are obtained, which are 28.6 and 4.6 times that of a uniform nanowire array, respectively. The threshold and maximum output are 17% lower and 613% higher than that of the uniform nanowire array laser, respectively, due to the narrower nanowire slits and stronger optical confinement. In addition, a low beam divergence angle of 2° is obtained due to the topological protection. This work may pave the way for the development of high-output, low-threshold, low-beam-divergence nanolasers.
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With the rapid growth of the Internet of Things (IoT), massive terminal devices are connected to the network, generating a large amount of IoT data. The reliable sharing of IoT data is crucial for fields such as smart home and healthcare, as it promotes the intelligence of the IoT and provides faster problem solutions. Traditional data sharing schemes usually rely on a trusted centralized server to achieve each attempted access from users to data, which faces serious challenges of a single point of failure, low reliability, and an opaque access process in current IoT environments. To address these disadvantages, we propose a secure and dynamic access control scheme for the IoT, named SDACS, which enables data owners to achieve decentralized and fine-grained access control in an auditable and reliable way. For access control, attribute-based control (ABAC), Hyperledger Fabric, and interplanetary file system (IPFS) were used, with four kinds of access control contracts deployed on blockchain to coordinate and implement access policies. Additionally, a lightweight, certificateless authentication protocol was proposed to minimize the disclosure of identity information and ensure the double-layer protection of data through secure off-chain identity authentication and message transmission. The experimental and theoretical analysis demonstrated that our scheme can maintain high throughput while achieving high security and stability in IoT data security sharing scenarios.
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Fiber-based flexible sensors have promising application potential in human motion and healthcare monitoring, owing to their merits of being lightweight, flexible, and easy to process. Now, high-performance elastic fiber-based strain sensors with high sensitivity, a large working range, and excellent durability are in great demand. Herein, we have easily and quickly prepared a highly sensitive and durable fiber-based strain sensor by dip coating a highly stretchable polyurethane (PU) elastic fiber in an MXene/waterborne polyurethane (WPU) dispersion solution. Benefiting from the electrostatic repulsion force between the negatively charged WPU and MXene sheets in the mixed solution, very homogeneous and stable MXene/WPU dispersion was successfully obtained, and the interconnected conducting networks were correspondingly formed in a coated MXene/WPU shell layer, which makes the as-prepared strain sensor exhibit a gauge factor of over 960, a large sensing range of over 90%, and a detection limit as low as 0.5% strain. As elastic fiber and mixed solution have the same polymer constitute, and tight bonding of the MXene/WPU conductive composite on PU fibers was achieved, enabling the as-prepared strain sensor to endure over 2500 stretching-releasing cycles and thus show good durability. Full-scale human motion detection was also performed by the strain sensor, and a body posture monitoring, analysis, and correction prototype system were developed via embedding the fiber-based strain sensors into sweaters, strongly indicating great application prospects in exercise, sports, and healthcare.
Subject(s)
Disgust , Nitrites , Transition Elements , Wearable Electronic Devices , Humans , Polyurethanes , Delivery of Health CareABSTRACT
OBJECTIVES: Knowledge of the predictors of nursing quality and safety remains a gap in global primary care research. This study examines organisational-level and nurse-level predictors of nurse-reported quality of care from a management perspective. METHODS: We recruited 175 primary care nurses in 38 community health centres (CHCs) varying by size and ownership in Jinan, Tianjin, Shenzhen and Shanghai. Guided by the Systems Engineering Initiative for Patient Safety model, the organisation-level predictors comprised organisational structure, organisational culture, psychological safety and organisational support, while the nurse-level predictors included organisational commitment and organisational citizenship behaviour. Nurse-reported quality of care was measured by two questions: "How do you rate the quality of care that you provide?" and "Do you often receive complaints from patients or their family members at work?" Multilevel linear regression models were used to examine the predictors of nurse-reported quality of care. RESULTS: Among the four organisation-level predictors, organisational structure, psychological safety and organisational support were positive predictors of nurse-reported quality of care. Nurses working in CHCs with highly hierarchical organisational structures (Coef. = 0.196, p = 0.000), a high level of organisational support (Coef. = 0.158, p = 0.017) and a high level of psychological safety (Coef. = 0.159, p = 0.035) were more likely to report high quality of care or less likely to receive medical complaints. In terms of nurse-level predictors, nurses willing to increase their knowledge through continuous education were more likely to report good quality of care (Coef. = 0.107, p = 0.049) and less likely to receive medical complaints from patients (Coef. = 0.165, p = 0.041). CONCLUSIONS: Potential management levers to improve quality of nursing care include formalised organisational structures, strong organisational support and a psychologically safe environment as well as the provision of training to facilitate continuous education. Implementing these recommendations is likely to enhance the nursing quality in primary care.
Subject(s)
Family , Organizational Culture , Humans , China , Primary Health Care , Quality of Health CareABSTRACT
The oil spill positioner is capable of real-time monitoring oil films on the sea surface. However, the lack of high-performance power supply methods greatly restricts the application of oil spill positioner. In this research, we design a high-performance self-powered oil spill positioner based on a soft-contact-triboelectric-nanogenerator (SC-TENG). This device achieves soft-contact by attaching rabbit fur to the rotor, which can effectively reduce frictional resistance, quickly transfer charge to the electrode, and improve the durability of the parts. First, we calculate the highest occupied molecular orbital and the lowest unoccupied molecular orbital of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF) molecules through first-principles simulations, and compared the ease of electron excitation between the two materials. The results show that the performance of SC-TENG with PVDF as dielectric material is significantly better than that of PTFE. At the same time, this phenomenon has been confirmed by experiments. On the basis of experimental and simulate research on two types of power management circuits, a bridge rectifier circuit with the function of converting alternating current to direct current is selected to realize the self-power supply of the oil spill positioner. Additionally, by optimizing the structure of the SC-TENG and employing a bridge rectifier circuit, the SC-TENG can achieve a maximum open-circuit voltage of 1400 V and a short-circuit current of 3.49µA, which are enough to light up 200 light-emitting diodes and power the oil spill positioner. Finally, we simulate the open-circuit voltage and short-circuit current of the SC-TENG on a six-degree-of-freedom platform and test its durability under real-world ocean wave conditions, all of which show excellent performance. This work develops an efficient wave energy conversion mechanism and successfully realizes the high-performance self-powering of the oil spill positioner, making oil spill monitoring more flexible and reliable.
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BACKGROUND: Multimorbidity is a global issue that presents complex challenges for physicians, patients, and health systems. However, there is a lack of research on the factors that influence physicians' confidence in managing multimorbidity within primary care settings, particularly regarding physicians' work conditions. OBJECTIVES: Drawing on the Job Demands-Resources Model, this study aims to investigate the level of confidence among Chinese primary care physicians in managing multimorbidity and examine the predictors related to their confidence. METHODS: Data were collected from 224 physicians working in 38 Community Healthcare Centres (CHCs) in Shanghai, Shenzhen, Tianjin, and Jinan, China. Work-family conflict (WFC) perceived organizational support (POS), self-directed learning (SDL), and burnout were measured. Physicians' confidence was assessed using a single item. Mediation effect analysis was conducted using the Baron and Kenny method. RESULTS: The results showed that the mean confidence score for physicians managing multimorbidity was 3.63 out of 5, only 20.10% rating their confidence level as 5. WFC negatively related physicians' confidence and POS positively related physicians' confidence in multimorbid diagnosis and treatment. Burnout fully mediated the relationship between WFC and physicians' confidence, and SDL partially mediated the relationship between POS and physicians' confidence. CONCLUSIONS: The confidence level of Chinese primary care physicians in managing multimorbidity needs improvement. To enhance physicians' confidence in managing multimorbid patients, CHCs in China should address WFC and burnout and promote POS and SDL.
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This paper proposes a high-security multi-level constellation shaping trellis-coded modulation (TCM) method based on clustering mapping rules, which is suitable for passive optical networks (PON) using three-dimensional (3D) carrier-less amplitude and phase modulation (CAP). This method combines the TCM mapping process with the constellation shaping and performs a multi-level mapping of the coded signal according to the classification label, so as to obtain better constellation shaping gain while expanding the coding gain of the TCM. The 3D constellation generated by the multi-level mapping adopts Chua's chaotic model for rotation encryption, which improves the ability of the optical access network to resist malicious attacks at the physical layer. Experiments show that 70 Gb/s (7×10 Gb/s) transmission is achieved on a 2 km weakly coupled seven-core fiber using the scheme proposed in this paper. At a bit error rate (BER) of 1 × 10-3, the difference in receiver sensitivity between the best and worst-performing cores is about 0.7 dB. The difference in receiver sensitivity between the cubic constellation and the chaotic spherical constellation is about 0.1 dB. The sensitivity of the chaotic spherical constellation receiver is about 6.98 dB higher than that of the 2D shaping constellation receiver. The experimental results show that the scheme has reliable security performance while improving the short-reach transmission capacity. It has broad application prospects in future short-reach communication research.
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BACKGROUND: China is currently making efforts to transform the current hospital-centric service delivery system to people-centred primary health care (PHC)-based delivery system, with service delivery organized around the health needs and expectations of people. To help direct China's PHC reform efforts, a profile of high-quality PHC from the public's perspective is required. OBJECTIVES: To profile high-quality PHC from the perspective of the Chinese public. METHODS: Semistructured interviews were conducted in 6 provinces (Henan, Shandong, Zhejiang, Shaanxi, Shanxi, and Heilongjiang) in China. In total, 58 interviewees completed the recorded interview. For transcription, trained research assistant listened to the recording of the interviews, summarizing each 30-s segment in English. Next, thematic analysis was performed on the narrative summaries to identify thematic families. RESULTS: Seven themes and 16 subthemes were generated from the analysis of our interview data. In order of their frequency, the interviewees expressed a high expectation for interpersonal communication and technical quality; followed by access, comprehensive care, cost, continuity, and coordination. CONCLUSIONS: Using qualitative data from 6 provinces in China, knowledge was generated to reveal the public's views and expectations for high-quality PHC. Our results confirm the urgent need for quality improvement efforts to improve patient experience and technical quality. The government also needs to further improve the delivery system and medical training programme to better meet public expectation in these areas, especially in establishing an innovative integrated primary care model, and strengthening interpersonal and clinical competency training for family doctors.
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BACKGROUND: As an efficient tumor immunotherapy, PD-1 antibody has been gradually used in clinical tumor treatment, but the low response rate and excessive immune response limit its extensive application. RESULTS: Herein, a therapeutic regime for the reinvigoration and activation of the tumor immune microenvironment is introduced to improve the anti-tumor effect of the PD-1 antibody. To comprehensively improve the effect of the immunotherapy and reduce excessive immune response, a biomimetic cascade targeting nanosystem, siRNA@PLOV, which was fused by photothermal sensitive liposomes (PTSLs) and attenuated Salmonella outer membrane vesicles (OMVs), was administered in the tumor therapy for targeting of tumor tissues and T cells within tumor respectively. The fused PLOVs which not only retained the biological character of the OMVs, but also enhanced the drug loading ability. The results demonstrated that the immunogenicity of OMVs and photothermal effects can obviously increase the infiltration of T cells and the silencing of CD38 can effectively improve the T cell cytotoxicity, especially combining with PD-1 antibody. CONCLUSIONS: Interesting, this study revealed that anti-PD-1 administration on the 5th day after siRNA@PLOV treatment had the best performance in killing tumors compared with other groups. In addition, this new therapeutic regime also presents a novel strategy for inducing "vaccine effects", conclusively highlighting its potential in preventing tumor recurrence and improving prognosis.
Subject(s)
Immunotherapy/methods , Neoplasms/therapy , Secretory Vesicles/chemistry , ADP-ribosyl Cyclase 1/antagonists & inhibitors , ADP-ribosyl Cyclase 1/genetics , ADP-ribosyl Cyclase 1/metabolism , Animals , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/therapeutic use , Bacterial Outer Membrane/metabolism , Cell Line, Tumor , Humans , Liposomes/chemistry , Mice , Mice, Inbred BALB C , Mice, Inbred ICR , Neoplasms/drug therapy , Programmed Cell Death 1 Receptor/immunology , RNA, Small Interfering/chemistry , RNA, Small Interfering/therapeutic use , Salmonella/metabolism , T-Lymphocytes/cytology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Transplantation, HeterologousABSTRACT
BACKGROUND Diabetes is one of the most commonly reported comorbidities among patients infected with SARS-CoV-2. This retrospective study of patients with SARS-CoV-2 infection was conducted to evaluate the association between blood glucose levels and the severity of COVID-19 pneumonia and patient mortality. MATERIAL AND METHODS A total of 268 patients with confirmed SARS-CoV-2 infection were included in this retrospective study. We obtained demographic characteristics, clinical symptoms, laboratory data, and survival information from patients' electronic medical records. Blood glucose was measured on admission to the hospital. Comorbidities, including hypertension, diabetes, chronic kidney disease, chronic liver disease, chronic obstructive pulmonary disease, and cardiovascular disease, were collected by self-reported medical history. RESULTS Significantly higher risks of severe COVID-19 were found in patients with blood glucose levels ranging from 5.53 to 7.27 mmol/L (odds ratio [OR], 3.98; 95% confidence interval [CI], 1.81-8.75) and in patients with blood glucose ≥7.27 mmol/L (OR, 12.10; 95% CI, 5.53-26.48) than in those with blood glucose <5.53 mmol/L. There was a trend toward better survival in patients with blood glucose <5.53 mmol/L than in patients with blood glucose from 5.53 to 7.27 mmol/L (hazard ratio [HR], 6.34; 95% CI, 1.45-27.71) and ≥7.27 mmol/L (HR, 19.37; 95% CI, 4.68-80.17). Estimated 10-day overall survival rates were 96.8%, 90.6%, and 69.3% in patients with blood glucose <5.53 mmol/L, 5.53 to 7.27 mmol/L, and ³7.27 mmol/L, respectively. CONCLUSIONS Hyperglycemia was association with severity of COVID-19 pneumonia and with increased patient mortality. These findings support the need for blood glucose monitoring and control of hyperglycemia in patients with COVID-19 pneumonia.
Subject(s)
Blood Glucose/metabolism , COVID-19/blood , Hyperglycemia/virology , Adult , Aged , Blood Glucose Self-Monitoring , COVID-19/metabolism , COVID-19/pathology , COVID-19/virology , Comorbidity , Female , Hospital Mortality , Hospitalization , Humans , Hyperglycemia/blood , Male , Middle Aged , Prognosis , Proportional Hazards Models , Retrospective Studies , Risk Factors , SARS-CoV-2/isolation & purification , Severity of Illness Index , Survival RateABSTRACT
Edge computing is a product of the evolution of IoT and the development of cloud computing technology, providing computing, storage, network, and other infrastructure close to users. Compared with the centralized deployment model of traditional cloud computing, edge computing solves the problems of extended communication time and high convergence traffic, providing better support for low latency and high bandwidth services. With the increasing amount of data generated by users and devices in IoT, security and privacy issues in the edge computing environment have become concerns. Blockchain, a security technology developed rapidly in recent years, has been adopted by many industries, such as finance and insurance. With the edge computing capability, deploying blockchain platforms/applications on edge computing platforms can provide security services for network edge environments. Although there are already solutions for integrating edge computing with blockchain in many IoT application scenarios, they slightly lack scalability, portability, and heterogeneous data processing. In this paper, we propose a trusted edge platform to integrate the edge computing framework and blockchain network for building an edge security environment. The proposed platform aims to preserve the data privacy of the edge computing client. The design based on the microservice architecture makes the platform lighter. To improve the portability of the platform, we introduce the Edgex Foundry framework and design an edge application module on the platform to improve the business capability of Edgex. Simultaneously, we designed a series of well-defined security authentication microservices. These microservices use the Hyperledger Fabric blockchain network to build a reliable security mechanism in the edge environment. Finally, we build an edge computing network using different hardware devices and deploy the trusted edge platform on multiple network nodes. The usability of the proposed platform is demonstrated by testing the round-trip time (RTT) of several important workflows. The experimental results demonstrate that the platform can meet the availability requirements in real-world usage scenarios.
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Drug resistance is one of the major obstacles in glioblastoma (GBM) treatments using temozolomide (TMZ) based conventional chemotherapy. Recent studies revealed that Hexokinase 2 (HK2)-mediated glycolysis is one of the sources, as the association of chemoresistance and the expression of HK2 was confirmed in multiple cancers. However, there has been little knowledge of the functional contribution of HK2 to TMZ resistance in GBM. In our study, we found that HK2 expression is crucial for GBM proliferation and chemoresistance. In contrast to the healthy brain, HK2 expression is much higher in human GBM, especially in those patients with GBM recurrence. High HK2 expression is negatively related to the overall survival in GBM patients. HK2 depletion in GBM cells suppressed the GBM cell proliferation and increased sensitivity to TMZ-induced apoptosis. Both HK2-mediated glycolysis and mitochondria permeability transition pore opening (MPTP) were associated with its function in chemoresistance. Furthermore, we also revealed that the abnormal expression of HK2 was modulated by the expression of HOTAIR, a long non-coding RNA (lncRNA). The absence of HOTAIR in GBM cells suppressed the HK2 expression in protein and mRNA level and, therefore, inhibited the cell proliferation and enhanced the cytotoxicity of TMZ both in vivo and in vitro. HOTAIR promoted the expression of HK2 by targeting mir-125, which suppressed the GBM cell proliferation and increased the TMZ-induced apoptosis. These findings shed light on a new therapeutic strategy in modulating HOTAIR/miR-125, which may interfere with the expression of HK2, and enhance the therapeutic sensitivity of GBM to TMZ.
Subject(s)
Drug Resistance, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Glioblastoma/genetics , Hexokinase/genetics , MicroRNAs/genetics , RNA, Long Noncoding/genetics , Apoptosis/genetics , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Humans , RNA InterferenceABSTRACT
BACKGROUND: Corneal transplantation is a common surgical intervention for restoring vision loss due to corneal damages. However, for cultural reasons, there is a huge shortage of donor corneas in China. Acellular porcine corneal stromas (APCSs) can be used as corneal substitutes in lamellar keratoplasty for corneal ulcers. This study was conducted to analyze the results of APCS use for herpes simplex keratitis (HSK). METHODS: The study involved HSK patients who underwent keratoplasty with APCSs from February 2016 to October 2017 in the second affiliated hospital of Zhejiang University. Patient data were collected at 7 days, 1 month, 3 months, 6 months, and at the last follow-up (7-25 months) postoperative. The corneal transparency, neovascularization, visual acuity, and graft stability were observed. RESULTS: Thirteen patients with HSK including five patients with corneal perforation were included in this study, nine patients underwent deep anterior lamellar keratoplasty (DALK) and five perforation patients underwent double lamellar keratoplasty. There were nine men and four women with an average age of 62.5 ± 5.6 years old (ranging from 52 to 70 years old). The mean postoperative follow-up duration was 15.1 ± 5.8 months (ranging from 7 to 25 months). At the last visit, visual acuity improved in nine patients (69.2%) compared with preoperative (P = 0.008).The grafts of seven individuals (53.8%) were completely transparent or slightly opaque; their corneal transparency score had improved significantly compared with before the surgery (P = 0.010). Various degrees of neovascularization were present in 11 of the 13 patients (84.6%), most neovascularization gradually stabilized. Graft dissolution occurred in three eyes (23.1%) during the observation period, two underwent regrafting, the other one became stable after treatment. Three patients underwent second allograft transplantation, two of which encountered APCS graft dissolution and one of the patients requested a human donor allograft transplantation due to transparency issues despite the absence of adverse issues. CONCLUSION: Acellular porcine corneal stroma seems to be effective in the treatment of HSK and can be used in HSK with corneal perforation by using double lamellar keratoplasty in an emergency.
Subject(s)
Corneal Stroma/transplantation , Corneal Transplantation/methods , Keratitis, Herpetic/surgery , Acyclovir/therapeutic use , Aged , Animals , Antiviral Agents/therapeutic use , Corneal Neovascularization , Corneal Opacity/etiology , Corneal Perforation/surgery , Female , Humans , Male , Middle Aged , Ophthalmic Solutions , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Swine , Transplantation, Heterologous , Treatment OutcomeABSTRACT
BACKGROUND: The majority of ruptured intracranial aneurysms are combined with subarachnoid hemorrhage, but patients with only intracerebral hematoma without any subarachnoid hemorrhage are extremely rare. CASE PRESENTATION: The patient was hospitalized due to sudden dizziness combined with slurred speech. The patient showed considerable decreased physical activity without any nuchal rigidity. Head CT showed hematoma in the left temporal lobe, and the shape of hematoma was extremely irregular. MRI indicated the absence of any vascular malformations. The patient was diagnosed with middle cerebral artery bifurcation aneurysm in the left by head CTA. Intracranial aneurysm clip and removal of hematoma in the left temporal lobe were performed under general anesthesia. The patient did not show any significant neurological dysfunction after the surgery and was followed up for 4 months after discharge with GOS score of 5 points. CONCLUSIONS: Intracranial hematoma with irregular morphology around the lateral fissure of the brain should be considered critical in order to avoid misdiagnosis and any possibility of missed diagnosis of vascular lesions, so as to ensure an exact therapeutic strategy with good prognosis for the patients.
Subject(s)
Aneurysm, Ruptured/diagnostic imaging , Intracranial Aneurysm/diagnostic imaging , Aneurysm, Ruptured/complications , Female , Hematoma/diagnostic imaging , Hematoma/etiology , Humans , Intracranial Aneurysm/complications , Male , Middle Aged , Subarachnoid Hemorrhage , Tomography, X-Ray ComputedABSTRACT
In this study, we developed a multifunctional device based on SnO2@rGO-coated fibers utilizing plasma treatment, dip coating, and microwave irradiation in sequence, and finally realized highly sensitive human motion monitoring, relatively good ethanol detection, and an obvious photo response. Moreover, the high level of comfort and compactness derived from highly elastic and comfortable fabrics contributes to the long-term availability and test accuracy. As an attempt at multifunctional integration of smart clothing, this work provides an attractive and relatively practical research direction.
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BACKGROUND: Meningeal carcinomatosis (MC) is characterized by diffuse infiltration of tumor cells in meninges. There is no tumor mass in the brain and parenchyma of the spinal cord. MC is divided into primary and metastatic types. MC cases were previously diagnosed postoperatively or at autopsy. Recent advances in spinal abbreviation cytology and imaging have led to increase in number of reported cases. In this study, we discuss the manifestations of MC patients based on magnetic resonance imaging (MRI) findings, as well as the correlation between the manifestations and pathology. CASE PRESENTATION: MC was confirmed in all three cases by lumbar puncture and gadopentetate dimeglumine-enhanced magnetic resonance imaging. Due to different primary diseases, the patients had specific imaging manifestations. CONCLUSION: Enhanced MRI examination is extremely sensitive for detecting abnormalities in meninges, which plays a very important role in the diagnosis of MC. Since meninges of some MC patients cannot be enhanced, the enhanced MRI examination cannot be replaced by conventional cerebrospinal abbreviation examination. Attribute to the diversity of MR contrast agents, which could provide higher lesion conspicuity and enhances lesion detection, there may be some more choices to improve the detection rate of MC patients and prolong their survival lifetime.
Subject(s)
Magnetic Resonance Imaging/methods , Meningeal Carcinomatosis/pathology , Meningeal Neoplasms/pathology , Adult , Contrast Media , Female , Humans , Male , Meningeal Carcinomatosis/surgery , Meningeal Neoplasms/surgery , Middle Aged , PrognosisABSTRACT
A surface-enhanced Raman scattering (SERS) method has been developed to determine the concentration of trichloroethylene (TCE) in environmental water. Au-core/Ag-shell nanoparticles containing 4-mercaptophenylboronic acid (4-MPBA) between the core and shell are used as the SERS substrate. 4-MPBA serves as an internal reference with a Raman shift at 534 cm-1. TCE reacts with 4-mercaptopyridine (4-MPy) in a so-called Fujiwara reaction. With the presence of TCE in water, the consumption of 4-MPy results in a change in the intensity of its Raman signal at 1220 cm-1. The ratio of the Raman shift at 1220 cm-1 and 534 cm-1 decreases linearly in the 0.2 to 1.0 µM TCE concentration range, and the detection limit of TCE is as low as 8 ppb (60 nM). The method has been successfully applied to the determination of TCE in spiked lake water. Graphical abstract Gold-core/silver-shell nanoparticles with internal reference embedded have been fabracated to improve the quantitative measurement of SERS. These nanoparticles as SERS substrates, are used to indirectly quantify the concentration of trichloroethylene (a typical halogenated organic compound) by the consumption of 4-mercaptopyridine through the Fujiwara reaction.
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The lasing characteristics of hybrid plasmonic AlGaAs/GaAs multiple quantum well (MQW) nanowire (NW) lasers beyond diffraction limit have been investigated by 3D finite-difference time-domain simulations. The results show that the hybrid plasmonic MQW NW has lower threshold gain over a broad diameter range in comparison with its photonic counterpart. Beyond the diffraction limit, the hybrid plasmonic MQW NW has a lowest threshold gain of 788 cm-1 at a diameter of 130 nm, and a cutoff diameter of 80 nm, half that of the photonic lasers. In comparison with the hybrid plasmonic core-shell NWs, the hybrid plasmonic MQW NWs exhibit significantly lower threshold gain, higher Purcell factor, and smaller cutoff diameter, which are attributed to the superior overlap between the hybrid plasmonic modes and gain medium, as well as a stronger optical confinement due to the grating-like effect of MQW structures. Moreover, the hybrid plasmonic MQW NW has a lower threshold gain than that of the core-shell NW over a broad wavelength range. The hybrid plasmonic MQW NW structure is promising for ultrasmall and low-consumption near-infrared nanolasers.
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The hepatitis B virus (HBV) is responsible for most of hepatocellular carcinoma (HCC). However, whether HBV plays an important role during hepatocarcinogenesis through effecting miRNAs remains unknown. Here, we reported that HBV up-regulated microRNA-181a (miR-181a) by enhancing its promoter activity. Simultaneously, we found that miR-181a inhibited apoptosis in vitro and promoted tumor cell growth in vivo. TNF receptor superfamily member 6 (Fas) was further identified as a target of miR-181a. We also found that Fas could reverse the apoptosis-inhibition effect induced by miR-181a. Moreover, HBV could inhibit cell apoptosis by down-regulating Fas expression, which could be reversed by miR-181a inhibitor. Our data demonstrated that HBV suppressed apoptosis of hepatoma cells by up-regulating miR-181a expression and down-regulating Fas expression, which may provide a new understanding of the mechanism in HBV-related HCC pathogenesis.