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1.
Opt Express ; 32(7): 11079-11091, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38570965

RESUMO

Freespace optical (FSO) communication in an outdoor setting is complicated by atmospheric turbulence (AT). A time-varying (TV) multiplexed orbital angular momentum (OAM) propagation model to consider AT under transverse-wind conditions is formulated for the first time, and optimized dynamic correction periods for various TV AT situations are found to improve the transmission efficiency. The TV nature of AT has until now been neglected from modeling of OAM propagation models, but it is shown to be important. First, according to the Taylor frozen-turbulence hypothesis, a series of AT phase screens influenced by transverse wind are introduced into the conventional angular-spectrum propagation analysis method to model both the temporal and spatial propagation characteristics of multiplexed OAM beams. Our model shows that while in weak TV AT, the power standard deviation of lower-order modes is usually smaller than that of higher-order modes, the phenomena in strong TV AT are qualitatively different. Moreover, after analyzing the effective time of each OAM phase correction, optimized dynamic correction periods for a dynamic feedback communication link are obtained. An optimized result shows that, under the moderate TV AT, both a system BER within the forward-error-correction limit and a low iterative computation volume with 6% of the real-time correction could be achieved with a correction period of 0.18 s. The research emphasizes the significance of establishing a TV propagation model for exploring the effect of TV AT on multiplexed OAM beams and proposing an optimized phase-correction mechanism to mitigate performance degradation caused by TV AT, ultimately enhancing overall transmission efficiency.

2.
Eur J Clin Invest ; : e14212, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591651

RESUMO

BACKGROUND: Bone morphogenetic protein 9 (BMP9) is a hepatokine that plays a pivotal role in the progression of liver diseases. Moreover, an increasing number of studies have shown that BMP9 is associated with hepatopulmonary syndrome (HPS), but its role in HPS is unclear. Here, we evaluated the influence of CBDL on BMP9 expression and investigated potential mechanisms of BMP9 signalling in HPS. METHODS: We profiled the circulating BMP9 levels in common bile duct ligation-induced HPS rat model, and then investigated the effects and mechanisms of HPS rat serum on pulmonary vascular endothelial dysfunction in rat model, as well as in primarily cultured rat pulmonary microvascular endothelial cells. RESULTS: Our data revealed that circulating BMP9 levels were significantly increased in the HPS rats compared to control group. Besides, the elevated BMP9 in HPS rat serum was not only crucial for promoting endothelial cell proliferation and tube formation through the activin receptor-like kinase1 (ALK1)-Endoglin-Smad1/5/9 pathway, but also important for accumulation of monocytes. Treatments with ALK1-Fc or silencing ALK1 expression to inhibit the BMP9 signalling pathway effectively eliminated these effects. In agreement with these observations, increased circulating BMP9 was associated with an increase in lung vessel density and accumulation of pro-angiogenic monocytes in the microvasculature in HPS rats. CONCLUSIONS: This study provided evidence that elevated circulating BMP9, secreted from the liver, promote pulmonary angiogenesis in HPS rats via ALK1-Endoglin-Smad1/5/9 pathway. In addition, BMP9-regulated pathways are also involved in accumulation of pro-angiogenic monocytes in the pulmonary microvasculature in HPS rats.

3.
Artif Intell Med ; 147: 102726, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38184357

RESUMO

Heparin is a critical aspect of managing sepsis after abdominal surgery, which can improve microcirculation, protect organ function, and reduce mortality. However, there is no clinical evidence to support decision-making for heparin dosage. This paper proposes a model called SOFA-MDP, which utilizes SOFA scores as states of MDP, to investigate clinic policies. Different algorithms provide different value functions, making it challenging to determine which value function is more reliable. Due to ethical restrictions, we cannot test all policies on patients. To address this issue, we proposed two value function assessment methods: action similarity rate and relative gain. We experimented with heparin treatment policies for sepsis patients after abdominal surgery using MIMIC-IV. In the experiments, TD(0) shows the most reliable performance. Using the action similarity rate and relative gain to assess AI policy from TD(0), the agreement rates between AI policy and "good" physician's actual treatment are 64.6% and 73.2%, while the agreement rates between AI policy and "bad" physician's actual treatment are 44.1% and 35.8%, the gaps are 20.5% and 37.4%, respectively. External validation using action similarity rate and relative gain based on eICU resulted in agreement rates of 61.5% and 69.1% with the "good" physician's treatment, and 45.2% and 38.3% with the "bad" physician's treatment, with gaps of 16.3% and 30.8%, respectively. In conclusion, the model provides instructive support for clinical decisions, and the evaluation methods accurately distinguish reliable and unreasonable outcomes.


Assuntos
Heparina , Sepse , Humanos , Heparina/uso terapêutico , Sepse/tratamento farmacológico , Algoritmos , Políticas , Unidades de Terapia Intensiva
4.
Front Biosci (Landmark Ed) ; 28(10): 272, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37919052

RESUMO

BACKGROUND: In addition to intrahepatic angiogenesis, patients with cholestasis cirrhosis develop extrahepatic vasculature disorders and functional disturbances of multiple organ systems. Without effective intervention, these vascular disorders will eventually turn into multiple organs vascular syndromes, including the brain, lung and other organ systems. However, studies on the pathogenesis of vascular alterations among extrahepatic organ disturbances are still carried out separately, which hampered the successful translation of preclinical studies to the human setting and required further mechanistic insight into these complications. This study aims to investigate the relationship between extrahepatic angiogenesis and multiple organ impairment, and whether the vascular endothelial growth factor (VEGF) family members and their receptors are involved in this process. METHODS: Pathological changes of the multiple organs were determined by histopathological and immunohistochemical staining in the established common bile duct ligation (CBDL) rats, and angiogenesis was estimated by microvessel density (MVD). Levels of the VEGF family members and their receptors in the serum and organ tissues were also measured by using enzyme-linked immunosorbent assays. RESULTS: The MVD and VEGF family members and their receptors were significantly increased in CBDL rats with multiple organ injury, especially in the liver, lung and cerebral cortex. Meanwhile, we noticed moderate elevation of soluble receptor of the vascular endothelial growth factor-1 (sFlt-1) in the liver, lung, and cerebral cortex, whereas the levels of placental growth factor (PLGF) increased significantly. CONCLUSIONS: Extrahepatic angiogenesis may represent a common pathophysiological basis for multiple organ dysfunction and the sFlt-1/PLGF ratio could offer an avenue for further studies to target extrahepatic angiogenesis in cholestatic cirrhosis.


Assuntos
Cirrose Hepática Biliar , Fator A de Crescimento do Endotélio Vascular , Ratos , Humanos , Feminino , Animais , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de Crescimento Placentário , Insuficiência de Múltiplos Órgãos
5.
J Clin Transl Hepatol ; 11(5): 1150-1160, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37577229

RESUMO

Background and Aims: The results of basic research implicate the vascular endothelial growth factor (VEGF) family as a potential target of hepatopulmonary syndrome (HPS). However, the negative results of anti-angiogenetic therapy in clinical studies have highlighted the need for markers for HPS. Therefore, we aimed to determine whether VEGF family members and their receptors can be potential biomarkers for HPS through clinical and experimental studies. Methods: Clinically, patients with chronic liver disease from two medical centers were enrolled and examined for HPS. Patients were divided into HPS, intrapulmonary vascular dilation [positive contrast-enhanced echocardiography (CEE) and normal oxygenation] and CEE-negative groups. Baseline information and perioperative clinical data were compared between HPS and non-HPS patients. Serum levels of VEGF family members and their receptors were measured. In parallel, HPS rats were established by common bile duct ligation. Liver, lung and serum samples were collected for the evaluation of pathophysiologic changes, as well as the expression levels of the above factors. Results: In HPS rats, all VEGF family members and their receptors underwent significant changes; however, only soluble VEGFR1 (sFlt-1) and the sFlt-1/ placental growth factor (PLGF) ratio were changed in almost the same manner as those in HPS patients. Furthermore, through feature selection and internal and external validation, sFlt-1 and the sFlt-1/PLGF ratio were identified as the most important variables to distinguish HPS from non-HPS patients. Conclusions: Our results from animal and human studies indicate that sFlt-1 and the sFlt-1/PLGF ratio in serum are potential markers for HPS.

6.
Front Med (Lausanne) ; 10: 1151996, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601798

RESUMO

Objective: Non-invasive methods for hemoglobin (Hb) monitoring can provide additional and relatively precise information between invasive measurements of Hb to help doctors' decision-making. We aimed to develop a new method for Hb monitoring based on mask R-CNN and MobileNetV3 with eye images as input. Methods: Surgical patients from our center were enrolled. After image acquisition and pre-processing, the eye images, the manually selected palpebral conjunctiva, and features extracted, respectively, from the two kinds of images were used as inputs. A combination of feature engineering and regression, solely MobileNetV3, and a combination of mask R-CNN and MobileNetV3 were applied for model development. The model's performance was evaluated using metrics such as R2, explained variance score (EVS), and mean absolute error (MAE). Results: A total of 1,065 original images were analyzed. The model's performance based on the combination of mask R-CNN and MobileNetV3 using the eye images achieved an R2, EVS, and MAE of 0.503 (95% CI, 0.499-0.507), 0.518 (95% CI, 0.515-0.522) and 1.6 g/dL (95% CI, 1.6-1.6 g/dL), which was similar to that based on MobileNetV3 using the manually selected palpebral conjunctiva images (R2: 0.509, EVS:0.516, MAE:1.6 g/dL). Conclusion: We developed a new and automatic method for Hb monitoring to help medical staffs' decision-making with high efficiency, especially in cases of disaster rescue, casualty transport, and so on.

7.
Opt Express ; 31(15): 25207-25219, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475331

RESUMO

We propose, what we believe to be, a novel method for high temperature sensing calibration based on the mechanism of alterable interferential fineness in Bragg hollow core fiber (BHCF). To verify the proof-of-concept, the fabricated sensing structure is sandwiched by two sections with different length of BHCF. Two interferential fineness fringes dominate the transmission spectrum, where the high-fineness fringes formed by anti-resonant reflecting optical waveguide (ARROW) plays the role for high temperature measurement. Meanwhile, the low-fineness fringes induced by short Fabry-Perot (F-P) cavity are exploited as temperature calibration. The experimental results show that the ARROW mechanism-based temperature sensitivity can reach 26.03 pm/°C, and the intrinsic temperature sensitivity of BHCF is 1.02 pm/°C. Here, the relatively lower magnitude of the temperature sensitivity is considered as the standard value since it merely relies on the material properties of silicon. Additionally, a large dynamic temperature range from 100 °C to 800 °C presents linear response of the proposed sensing structure, which may shine the light on the sensing applications in the harsh environment.

8.
Opt Express ; 30(21): 37526-37535, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258340

RESUMO

Ultrahigh-order optical orbital angular momentum (OAM) states of the identification over ±270 orders are implemented by annular phase grating (APG) and Gaussian beams with different wavelengths. Particularly, the far-field diffraction intensity patterns feature the spiral stripes instead of Hermitian-Gaussian (HG)-like fringes. It's worth noting that the spiral stripes present uniform distribution, thus the order of OAM states can be intuitively acquired. More specifically, the OAM states can be confirmed from the total amount and rotating direction of the spiral stripes. Compared with traditional methods, the propose scheme contributes to the perfect-distributed and sharper spiral stripes. Moreover, it also makes an easier observation of the patterns in the CCD camera with limited imaging targets. In our experimental setup, the optical filter is removed and the APG parameters are not strictly required. Therefore, the propose optical transmission system is equipped with the advantages of efficiency, robustness and low cost, which paves a promising way for the communication capacity enhancement.

9.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 34(3): 239-244, 2022 03.
Artigo em Chinês | MEDLINE | ID: mdl-35574738

RESUMO

World Society of Emergency Surgery (WSES), in conjunction with Surgical Infection Society Europe (SIS-E), World Surgical Infection Society (WSIS), American Association for the Surgery of Trauma (AAST), and Global Alliance for Infection in Surgery (GAIS) developed guideline about the management of acute abdomen in immunocompromised patients, which was published in the World Journal of Emergency Surgery (WJES) on August 9, 2021. The guidelines elaborate on the definition, classification, diagnosis and treatment of immunocompromised patients. In addition, based on evidence-based medicine, it provides guidance and suggestion on the management of specific acute abdominal infections in immunocompromised patients, common acute abdominal infections in transplanted patients, patients with human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS), as well as perioperative steroid management. An interpretation of the guideline was performed to accomplish a better understanding the current status and recommendations for the management of acute abdominal conditions in immunocompromised patients, and to make forward suggestions on its limitations.


Assuntos
Abdome Agudo , Infecções Intra-Abdominais , Doença Aguda , Europa (Continente) , Humanos , Hospedeiro Imunocomprometido , Estados Unidos
10.
Opt Express ; 30(9): 15766-15776, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473290

RESUMO

The ring resonator is a versatile and functional component in the silicon-based integrated optical circuit. Most of the previously reported ring resonators work in the single-mode case. With the rapid development of mode division multiplexing technology, a multimode ring resonator (MMRR) has been proposed and the usage beyond the limit of a conventional single mode ring resonator has been explored. However, the reported MMRRs are either large in size or low in quality factor. In this paper, we designed a compact silicon MMRR with a small bending radius of 15µm, in which the three lowest TE modes all have high Q-factors. For suppressing the mode loss and inter-mode crosstalk in MMRR, a multimode waveguide bend (MWB) with mode adiabatic evolution was designed based on transformation optics and waveguide shape optimization. The independent excitation of each order mode of the MMRR is realized by using bending directional coupler and asymmetric directional coupler. We successfully fabricated the device on a silicon-on-insulator (SOI) platform using simple one-step lithography. The measured loaded Q-factors of the three lowest TE modes are 5.9 × 104, 4.5 × 104, and 4.7 × 104, respectively.

11.
Front Optoelectron ; 15(1): 20, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-36637546

RESUMO

The slab effective index difference between the transverse-electric (TE) and transverse-magnetic (TM) polarizations was utilized to obtain complete photonic bandgap (CPBG) in a silicon nitride (SixNy) photonic crystal slab. For this, coincident frequency range in the TE photonic bandgap (PBG) and TM PBG, which denotes the CPBGs of the slab, must be found with the same structure. Through adjusting the effective index pair of TE and TM polarizations by changing the thickness of the SixNy core layer, and also optimizing the structure parameters within the photonic crystal plane, a large normalized CPBG of 5.62% was theoretically obtained in a slab of SixNy with a refractive index of 2.5. Moreover, based on the obtained CPBG, a microcavity which could support both TE and TM polarization was theoretically demonstrated. The cavity modes for different polarizations were both well confined, which proved the reliability of the CPBG. In addition, using the same method, the lowest refractive index of SixNy on silica slab for a CPBG could be extended to as low as 2. The results indicate that there is potential for development of various high-performance CPBG devices based on SixNy slab technology.

12.
Opt Lett ; 46(22): 5558-5561, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34780402

RESUMO

We find that in a suitably designed photonic crystal (PC) certain high-order photonic bands are less affected by the refractive-index ratio (RIR) than low-order bands, enabling the realization of a robust and complete two-dimensional (2D) photonic bandgap in a moderate refractive-index-ratio PC. A detailed theoretical investigation of low- and high-order bandgaps in a series of PCs with different configurations is performed that shows that high-order bands may favor substantial complete photonic bandgaps (CPBGs) for systems with a moderate RIR. Furthermore, the importance of the geometry and structural parameters on achieving a high-order CPBG is found. Specifically, a hexagonal lattice PC of annular-hole-peripheral connecting rods is proposed, which can support a CPBG with a refractive-index ratio (RIR) as low as nhigh:nlow=2.1; to the best of our knowledge, this is the lowest RIR used to obtain a 2D CPBG in a PC.

13.
Cytogenet Genome Res ; 161(5): 272-277, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34289478

RESUMO

The genus Dracaena is the main source of dragon's blood, which is a plant resin and has been used as traditional medicine since ancient times in different civilizations. However, the chromosome numbers and karyotypes present in this genus remain poorly understood. In this study, fluorescence in situ hybridization (FISH) using oligonucleotide probes for ribosomal DNAs (5S and 45S rDNA) and telomeric repeats (TTTAGGG)3 was applied to analyze 4 related species: Dracaena terniflora Roxb., Dracaena cambodiana Pierre ex Gagnep., Aizong (Dracaena sp.), and Dracaena cochinchinensis (Lour.) S.C. Chen. In all 4 species, both 5S and 45S rDNA showed hybridization signals in the paracentromeric region of a pair of chromosomes; the sizes of the 45S rDNA signals were larger than those of the 5S rDNA. Importantly, the telomeric repeat signals were located in the telomeric regions of almost all chromosomes. The results indicated that the chromosome number of all 4 Dracaena species is 2n = 40, and the lengths of the mitotic metaphase chromosomes range from 0.99 to 2.98 µm. Our results provide useful cytogenetic information, which will be beneficial to future studies in genome structure of the genus Dracaena.


Assuntos
Mapeamento Cromossômico/métodos , Cromossomos de Plantas/química , Dracaena/genética , Cariótipo , Centrômero , China , Dracaena/classificação , Hibridização in Situ Fluorescente/métodos , Cariotipagem/métodos , Filogeografia , RNA Ribossômico/genética , RNA Ribossômico 5S/genética , Telômero
14.
Mitochondrial DNA B Resour ; 6(8): 2114-2116, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34263033

RESUMO

Wurfbainia neoaurantiaca is a medicinal plant endemic to Yunnan Province, China. In this study, its complete chloroplast genome was assembled and characterized. The total genome size of W. neoaurantiaca was 158,484 bp in length, consisting of a large single-copy region (LSC), a small single-copy region (SSC) and two inverted repeat regions (IRs) with 88,605 bp, 15,285 bp and 29,822 bp, respectively. Its GC content was 36.08%. The chloroplast genome encoded 113 unique genes, including 79 protein-coding, 30 tRNA, and four rRNA genes. The result of the phylogenetic analysis indicated that W. neoaurantiaca was related to W. villosa var. xanthioides and supported de Boer's classification that W. compacta, W. longiligularis, W. neoaurantiaca, W. villosa, W. villosa var. xanthioides and Amomum krervanh belonged to the Wurfbainia Clade.

15.
Opt Express ; 28(23): 35395-35412, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33182986

RESUMO

The focusing apodized subwavelength grating coupler (F-ASGC) has advantages of high coupling efficiency, small footprint and simple fabrication process, which make it a popular component for chip-scale coupling and testing of integrated optical circuit. However, the design of F-ASGC based on effective medium theory lacks accuracy, causing the drawbacks of peak wavelength deviation and performance degradation. In this work, we propose a deterministic design method of F-ASGC. Our grating coupler is formed by assembling various subwavelength grating units according to their complex effective indexes. The complex effective indexes of these grating units are accurately obtained by the weak form calculation. Then combining with transformation optics, we strictly analyze the F-ASGC for the first time. The simulation results show that the deterministically designed F-ASGC has high coupling efficiency of -2.51 dB, 3 dB bandwidth of 51 nm, and accurate central wavelength of 1553.1 nm. And we also fabricated it on the commercial SOI wafer. The measured maximum efficiency is -3.10 dB, the 3 dB bandwidth is 55 nm, and the central wavelength is 1551.5 nm.

16.
Chin J Nat Med ; 18(8): 594-605, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32768166

RESUMO

To ensure the safety of medications, it is vital to accurately authenticate species of the Apocynaceae family, which is rich in poisonous medicinal plants. We identified Apocynaceae species by using nuclear internal transcribed spacer 2 (ITS2) and psbA-trnH based on experimental data. The identification ability of ITS2 and psbA-trnH was assessed using specific genetic divergence, BLAST1, and neighbor-joining trees. For DNA barcoding, ITS2 and psbA-trnH regions of 122 plant samples of 31 species from 19 genera in the Apocynaceae family were amplified. The PCR amplification for ITS2 and psbA-trnH sequences was 100%. The sequencing success rates for ITS2 and psbA-trnH sequences were 81% and 61%, respectively. Additional data involved 53 sequences of the ITS2 region and 38 sequences of the psbA-trnH region were downloaded from GenBank. Moreover, the analysis showed that the inter-specific divergence of Apocynaceae species was greater than its intra-specific variations. The results indicated that, using the BLAST1 method, ITS2 showed a high identification efficiency of 97% and 100% of the samples at the species and genus levels, respectively, via BLAST1, and psbA-trnH successfully identified 95% and 100% of the samples at the species and genus levels, respectively. The barcode combination of ITS2/psbA-trnH successfully identified 98% and 100% of samples at the species and genus levels, respectively. Subsequently, the neighbor joining tree method also showed that barcode ITS2 and psbA-trnH could distinguish among the species within the Apocynaceae family. ITS2 is a core barcode and psbA-trnH is a supplementary barcode for identifying species in the Apocynaceae family. These results will help to improve DNA barcoding reference databases for herbal drugs and other herbal raw materials.


Assuntos
Apocynaceae/classificação , Código de Barras de DNA Taxonômico , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Plantas Medicinais/classificação , Apocynaceae/genética , China , Folhas de Planta , Plantas Medicinais/genética
17.
J Econ Entomol ; 113(2): 654-659, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-31828311

RESUMO

Heortia vitessoides Moore is the most serious insect defoliator of Aquilaria sinensis (Lour.) Gilg, an endangered and economically important plant that produces highly prized agarwood. Samples from recently identified indigenous natural populations of Trichogramma pintoi Voegele were collected from H. vitessoides eggs in A. sinensis forests in Yunnan Province, China. To assess the potential capacity of this parasitoid for use as a biological control agent, its functional response, female reproductive potential, and male insemination capacity were investigated in this study. Females successfully parasitized 1- to 4-d-old eggs of H. vitessoides but failed to parasitize 5- to 8-d-old eggs. The parasitoid exhibited a Holling type II functional response, and the estimated maximum numbers of 1- to 4-d-old H. vitessoides eggs parasitized by a single T. pintoi female were 38.1, 29.8, 26.0, and 22.2 eggs over a 24-h period, respectively. Additionally, the parasitoid's average lifetime fecundity was 89.8 ± 2.5 eggs, of which 66.26% were laid within the first 2 d. The average number of total females that mated with a male in his lifetime (4.70 ± 0.13 d) was 10.4, and the average number of total daughters of a male was 292.1. On day 1 of male adult life, the greatest number of females were inseminated by males, and the most daughters were produced; however, the number of copulations and insemination ability decreased rapidly with male age. These results suggest that T. pintoi is a promising candidate for inundative release against H. vitessoides in China, and these findings will guide efforts in achieving mass production of this parasitoid.


Assuntos
Himenópteros , Lepidópteros , Mariposas , Animais , China , Feminino , Masculino , Óvulo
18.
BMC Anesthesiol ; 19(1): 103, 2019 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-31185905

RESUMO

BACKGROUND: Ultrasound guidance might decrease the incidence of local anesthetics systemic toxicity (LAST) for many peripheral nerve blocks compared with nerve stimulator guidance. However, it remains uncertain whether ultrasound guidance is superior to nerve stimulator guidance for deep nerve block of the lower extremity. This study was designed to investigate whether deep nerve block with ultrasound guidance would decrease the incidence of LAST compared with that with nerve stimulator guidance, and to identify associated risk factors of LAST. METHODS: Three hundred patients undergoing elective lower limb surgery and desiring lumbar plexus blocks (LPBs) and sciatic nerve blocks (SNBs) were enrolled in this study. The patients were randomly assigned to receive LPBs and SNBs with ultrasound guidance (group U), nerve stimulator guidance (group N) or dual guidance (group M). The primary outcome was the incidence of LAST. The secondary outcomes were the number of needle redirection, motor and sensory block onset and nerve distribution restoration time, as well as associated risk factors. RESULTS: There were 18 patients with LAST, including 12 in group U, 4 in group N and 2 in group M. By multiple comparisons among the three groups, we found that the incidence of LAST in group U (12%) was significantly higher than that in group N (4%)(P = 0.037) and group M(2%)(P = 0.006). The OR of LAST with hepatitis B (HBV) infection and the female sex was 3.352 (95% CI,1.233-9.108, P = 0.013) and 9.488 (95% CI,2.142-42.093, P = 0.0004), respectively. CONCLUSIONS: Ultrasound guidance, HBV infection and the female sex were risk factors of LAST with LPBs and SNBs. For patients infected with HBV or female patients receiving LPBs and SNBs, we recommended that combined ultrasound and nerve stimulator guidance should be used to improve the safety. TRIAL REGISTRATION: This study was approved by the Ethical Committee of the First Affiliated Hospital of Army Medical University. The protocol was registered prospectively with the Chinese Clinical Trial Registry ( ChiCTR-IOR-16008099 ) on March 15, 2016.


Assuntos
Anestésicos Locais/efeitos adversos , Bloqueio Nervoso/métodos , Adulto , Método Duplo-Cego , Estimulação Elétrica/métodos , Feminino , Humanos , Lidocaína , Plexo Lombossacral/efeitos dos fármacos , Masculino , Fatores de Risco , Ropivacaina , Nervo Isquiático/efeitos dos fármacos , Ultrassonografia de Intervenção/métodos , Adulto Jovem
20.
Opt Express ; 26(14): 18341-18350, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114015

RESUMO

In this paper, a high resolution and large dynamic range fiber optic temperature sensor without measurement crosstalk has been proposed. Two combinational mechanisms of anti-resonant reflecting optical waveguide and inline Mach-Zehnder interference structure are integrated in single hole twin eccentric cores fiber. The dual-effect composite spectrum is consist of several dominant resonant wavelengths and comb pattern, which are corresponding to the two above-mentioned mechanisms. Gauss fit and fast Fourier transform filtering are used for extracting the resonant wavelengths and comb spectrum, respectively. Accordingly, the temperature sensitivity of 42.18pm/°C and 2.057nm/°C are achieved by tracking the coherent decrease point. The lower sensitivity can guarantee a large dynamic range, while the higher one will contribute to the enhanced resolution. Therefore, the temperature monitoring is the combination of large dynamic range and enhanced resolution. Moreover, the size of the ultracompact sensor is only 950µm, which has a great potential for engineering applications.

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