With the development of mid-infrared (MIR) photoelectric devices, mid-infrared spectroscopy has become one of the important methods for non-invasive detection of blood glucose. The mid-infrared region (4000 - 400 cm&l...With the development of mid-infrared (MIR) photoelectric devices, mid-infrared spectroscopy has become one of the important methods for non-invasive detection of blood glucose. The mid-infrared region (4000 - 400 cm<sup>-1</sup>) has the well-known fingerprint region (1200 - 800 cm<sup>-1</sup>) of glucose, which has clearer characteristic absorption peaks and better specificity. There is a lot of molecular information about glucose in the MIR. The non-invasive detection of blood glucose by mid-infrared spectroscopy needs to achieve certain accuracy, and the quantitative model is an important factor affecting the accuracy of glucose detection. In this paper, the samples of imitation solution containing only glucose and the samples of imitation mixed solution are taken as the research objects, and the mid-infrared spectral data of the samples are collected. The full spectrum partial least squares Regression (PLSR) model, SNV + Ctr-PLSR model, MSC + Ctr-PLSR model, and convolutional neural networks (CNN) model of 3000 - 900 cm<sup>-1</sup> band were constructed. Full spectrum PLS model and CNN model of 1200 - 900 cm<sup>-1</sup> band were constructed. The experimental results show that the optimal model of the two bands is CNN, then the correlation coefficient of prediction set (Rp) of 3000 - 900 cm<sup>-1</sup> band is 0.95, and the root mean square error of pre-diction set (RMSEP) value is 22.10. The Rp of 1200 - 900 cm<sup>-1</sup> band is 0.95, and the RMSEP value is 22.54. The research results show that CNN is a promising method, which has higher accuracy than PLSR, and is especially suitable for modeling human complex environment. In addition, the study provides a theoretical and practical basis for CNN in feature selection and model interpretation.展开更多
Whether in the monitoring of critically ill patients such as shock, respiratory failure, brain injury, or in major anesthesia surgeries, it is necessary to evaluate the patient’s pO<sub>2</sub> and pH. An...Whether in the monitoring of critically ill patients such as shock, respiratory failure, brain injury, or in major anesthesia surgeries, it is necessary to evaluate the patient’s pO<sub>2</sub> and pH. An optical fiber sensor presented is capable of monitoring the presence of oxygen partial pressure (pO<sub>2</sub>) and pH in the real-time. The sensor is based on fluorescence sensing of polymer immobilized in the oxygen/pH-sensitive membranes and covalently attached to the optical fiber probe. The design of this sensor uses LED as light source, which is an excitation light source, inducing specific wavelengths of fluorescence on the oxygen/pH-sensitive membrane. The intensity and lifetime of fluorescence are related to the pO<sub>2</sub> and pH. So the pO<sub>2</sub> and pH can be measured by the relationship between the pO<sub>2</sub>/pH values and the intensity and lifetime of fluorescence. The signal conditioning system based on DSP and STM32 was used to store and process data, and display test values. The response of the sensor for pO<sub>2</sub> and pH monitoring with nitrogen (N<sub>2</sub>) as a balancing gas in the laboratory was performed. Finally, the oxygen/pH sensing scheme presented in this work is intended for using in biological, medical and environmental applications.展开更多
When a proton reduction cocatalyst is loaded on an n-type semiconductor for photocatalytic overall water splitting(POWS),the location of water oxidation sites is generally considered at the surface of the semiconducto...When a proton reduction cocatalyst is loaded on an n-type semiconductor for photocatalytic overall water splitting(POWS),the location of water oxidation sites is generally considered at the surface of the semiconductor due to upward band-bending of n-type semiconductor which may ease the transfer of the photogenerated holes to the surface.However,this is not the case for Pt/SrTiO_(3),a model semiconductor based photocatalyst for POWS.It was found that the photogenerated holes are more readily accumulated at the interface between Pt cocatalyst and SrTiO_(3) photocatalyst as probed by photo-oxidative deposition of PbO_(2),indicating that the water oxidation sites are located at the interface between Pt and SrTiO_(3).Electron paramagnetic resonance and scanning transmission electron microscope studies suggest that the interfacial oxygen atoms between Pt and SrTiO_(3) in Pt/SrTiO_(3) after POWS are more readily lost to form oxygen vacancies upon vacuum heat treatment,regardless of Pt loading by photodeposition or impregnation methods,which may serve as additional support for the location of the active sites for water oxidation at the interface.Density functional theory calculations also suggest that the oxygen evolution reaction more readily occurs at the interfacial sites with the lowest overpotential.These experimental and theoretical studies reveal that the more active sites for water oxidation are located at the interface between Pt and SrTiO_(3),rather than on the surface of SrTiO_(3).Hence,the tailor design and control of the interfacial properties are extremely important for the achievement or improvement of the POWS on cocatalyst loaded semiconductor photocatalyst.展开更多
Understanding the processes of charge generation, transfer and capture is important for the design and synthesis of efficient photocatalysts. In this work, light-induced charge separation and effect of O_(2) on electr...Understanding the processes of charge generation, transfer and capture is important for the design and synthesis of efficient photocatalysts. In this work, light-induced charge separation and effect of O_(2) on electron transfer processes in SrTiO_(3) were investigated by electron paramagnetic resonance(EPR). It was found that photoinduced electron transfer from O_(2)- to Ti^(4+) produced Ti^(3+) and O- redox radical pairs under vacuum condition. Under oxygen atmosphere, however, surface bound superoxide radicals O_(2)-were formed by electron reduction of adsorbed oxygen at initial photoirradiation stage, and quenched by the reverse electron transfer to Ti^(4+) upon further photoirradiation. Formation of long-lived charge separation associated [Ti^(3+)---O-] species and the reversibility of surface bound superoxide radicals mediating the processes of photogenerated electrons may be accountable for the high activity of SrTiO_(3) in photocatalytic water splitting reaction.展开更多
We consider asymptotic behaviors of the Vlasov-Poisson system with radiation damping in three space dimensions.For any smooth solution with compact support,we prove a sub-linear growth estimate of its velocity support...We consider asymptotic behaviors of the Vlasov-Poisson system with radiation damping in three space dimensions.For any smooth solution with compact support,we prove a sub-linear growth estimate of its velocity support.As a consequence,we derive some new estimates of the charge densities and the electrostatic field in this situation.展开更多
Background:Concurrent chemoradiotherapy(CCRT)is the standard treatment for locally advanced esophageal squamous cell carcinoma(ESCC).However,the optimal radiotherapy regimen,particularly in terms of total dose and pla...Background:Concurrent chemoradiotherapy(CCRT)is the standard treatment for locally advanced esophageal squamous cell carcinoma(ESCC).However,the optimal radiotherapy regimen,particularly in terms of total dose and planned range of irradiation field,remains unclear.This phase III clinical trial aimed to compare the survival benefits between different radiation doses and different target fields.Methods:This trial compared two aspects of radiation treatment,total dose and field,using a two-by-two factorial design.The high-dose(HD)group received 59.4 Gy radiation,and the standard-dose(SD)group received 50.4 Gy.The involved field irradiation(IFI)group and elective nodal irradiation(ENI)group adopted different irradiation ranges.The participants were assigned to one of the four groups(HD+ENI,HD+IFI,SD+ENI and SD+IFI).The primary endpoint was overall survival(OS),and the secondary endpoints included progressionfree survival(PFS).The synergy indexwas used to measure the interaction effect between dose and field.Results:The interaction analysis did not reveal significant synergistic effects between the dose and irradiation field.In comparison to the target field,patients in IFI or ENI showed similar OS(hazard ratio[HR]=0.99,95%CI:0.80-1.23,p=0.930)and PFS(HR=1.02,95%CI:0.82–1.25).TheHDtreatment did not show significantly prolonged OS compared with SD(HR=0.90,95%CI:0.72–1.11,p=0.318),but it suggested improved PFS(25.2 months to 18.0 months).Among the four groups,the HD+IFI group presented the best survival,while the SD+IFI group had the worst prognosis.No significant difference in the occurrence of severe adverse events was found in dose or field comparisons.Conclusions:IFI demonstrated similar treatment efficacy to ENI in CCRT of ESCC.The HD demonstrated improved PFS,but did not significantly improve OS.The dose escalation based on IFI(HD+IFI)showed better therapeutic efficacy than the current recommendation(SD+ENI)and is worth further validation.展开更多
The ORF9b protein,derived from the nucleocapsid’s open-reading frame in both SARS-CoV and SARS-CoV-2,serves as an accessory protein crucial for viral immune evasion by inhibiting the innate immune response.Despite it...The ORF9b protein,derived from the nucleocapsid’s open-reading frame in both SARS-CoV and SARS-CoV-2,serves as an accessory protein crucial for viral immune evasion by inhibiting the innate immune response.Despite its significance,the precise regulatory mechanisms underlying its function remain elusive.In the present study,we unveil that the ORF9b protein of SARS-CoV-2,including emerging mutant strains like Delta and Omicron,can undergo ubiquitination at the K67 site and subsequent degradation via the proteasome pathway,despite certain mutations present among these strains.Moreover,our investigation further uncovers the pivotal role of the translocase of the outer mitochondrial membrane 70(TOM70)as a substrate receptor,bridging ORF9b with heat shock protein 90 alpha(HSP90α)and Cullin 5(CUL5)to form a complex.Within this complex,CUL5 triggers the ubiquitination and degradation of ORF9b,acting as a host antiviral factor,while HSP90αfunctions to stabilize it.Notably,treatment with HSP90 inhibitors such as GA or 17-AAG accelerates the degradation of ORF9b,leading to a pronounced inhibition of SARS-CoV-2 replication.Single-cell sequencing data revealed an up-regulation of HSP90αin lung epithelial cells from COVID-19 patients,suggesting a potential mechanism by which SARS-CoV-2 may exploit HSP90αto evade the host immunity.Our study identifies the CUL5-TOM70-HSP90αcomplex as a critical regulator of ORF9b protein stability,shedding light on the intricate host–virus immune response dynamics and offering promising avenues for drug development against SARS-CoV-2 in clinical settings.展开更多
We have designed and synthesized NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋. magnetic nano- phosphors with combined dual-mode downconversion （DC） and upconversion （UC） photoluminescence upon 800 run excitation. Hexagonal-phas...We have designed and synthesized NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋. magnetic nano- phosphors with combined dual-mode downconversion （DC） and upconversion （UC） photoluminescence upon 800 run excitation. Hexagonal-phase NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋ nanocrystals （NCs） with an average size of 21 nm were synthesized using a solvothermal approach. Nd^3＋, Yb^3＋, Tm^3＋ triple-doped NaGdF4 NCs exhibit a broad range of photoluminescence peaks covering a near infrared first/second window （860-900, 1,000, and 1,060 nm）, and visible emission including blue （475 nm）, green （520 and 542 nm） and yellow （587 nm） after excitation at 800 nm. A mechanism involving circulation of energy over Gd^3＋ sublattices as bridge ions and final trapping by the initial activator ions （Nd^3＋） has been proposed. Penetration depth studies indicate that NIR emission is easily detected even at a large tissue thickness of 10 mm. These paramagnetic nanophosphors demonstrate a large magnetization value of 1.88 emu/g at 20 kOe and longitudinal relaxivity value of 1.2537 mM-1.S-1 as a Tl-weighted magnetic resonance imaging contrast agent. These NaGdF4：Nd^3＋, Yb^3＋ Tm^3＋ NCs are promising for applications in biological and magnetic resonance imaging.展开更多
We present a ballistocardiogram(BCG)measurement system for obtaining the BCG signal.The performance of the BCG measurement system was tested,including the dynamic response frequency of the platform(32 Hz with a 75 kg ...We present a ballistocardiogram(BCG)measurement system for obtaining the BCG signal.The performance of the BCG measurement system was tested,including the dynamic response frequency of the platform(32 Hz with a 75 kg load),and the signal to noise ratio of the system(minimum 23 dB).Factors that could influence BCG recording during measurement were investigated by collecting data from 48 healthy subjects(28 males and 20females).The basic features of the BCG signal,such as the amplitude and time interval,were extracted,and differences by gender were analyzed.A correlation between the IJ amplitude(amplitude difference between I-and J-peak)and the respiration phase was found(R2=0.49).The BCG signals for both sitting(SiBCG)and standing(StBCG)postures were obtained using this system.These showed that the StBCG amplitudes were larger than those of SiBCG but there was no significant difference in the time intervals.The robustness of our system was verified,and its potential for non-invasive cardiac activity monitoring was demonstrated.展开更多
Background:To analyze the clinical features of brain tumor-related epilepsy(BTRE)and explore the factors influencing the identification of epilepsy-associated tumor(EAT),in order to advance the clinical understanding ...Background:To analyze the clinical features of brain tumor-related epilepsy(BTRE)and explore the factors influencing the identification of epilepsy-associated tumor(EAT),in order to advance the clinical understanding of BTRE and EAT.Methods:Intracranial tumor origin and location as well as the type of epilepsy were retrospectively reviewed in 153 BTRE patients.The patients were further divided into the EAT and non-EAT groups,and comparisons were made for age,sex,tumor origin and location,and epilepsy type between the two groups.Results:The 153 BTRE patients were divided into 78 cases with primary intracranial tumor and 75 cases with tumor originating from extracranial metastasis,according to the origin of tumor.According to the location of tumor,116 cases had tumor lesions located in the brain parenchyma,and 37 cases had tumor lesions located in the meninges.Further,in the group with a brain parenchyma location,77 cases had single lobular involvement,and 39 cases had multiple-lobular involvement;84 cases had tumor lesions located in one hemisphere and 32 cases in both hemispheres.According to the type of epilepsy,92 cases had generalized seizures,and 61 cases had focal seizures.The type of epilepsy did not significantly correlate with the origin of intracranial tumor,the location of tumor lesions(in brain parenchyma or meninges)(P>0.05),or the hemispherical location(in one or two hemispheres)of lesions(P>0.05),but was significantly related with the lobular localization of lesions(P<0.05).The 153 cases of BTRE consisted of 87 EAT and 66 non-EAT,with significant differences in the origin,location and type(being glioma/non-glioma)of tumor.Logistic regression analysis showed that the type of tumor(i.e.whether being glioma)served as an independent factor for EAT identification;the lower the World Health Organization grade of glioma,the more likely the EAT is to be diagnosed(P<0.05).Conclusion:The majority of BTRE patients in this study had tumors located in the brain parenchyma.In addition,the patients with generalized seizures outnumbered those with focal seizures,and the type of epilepsy was correlated with the lobular location of tumor lesions.The EATs are mostly low-grade gliomas.展开更多
Primary chemotherapy options for colorectal cancer(CRC)involve four key drugs:fluorouracils(5-FU),oxaliplatin,irinotecan and raltitrexed.The first-line regimen consists of 5-FU and leucovorin combined with oxaliplatin...Primary chemotherapy options for colorectal cancer(CRC)involve four key drugs:fluorouracils(5-FU),oxaliplatin,irinotecan and raltitrexed.The first-line regimen consists of 5-FU and leucovorin combined with oxaliplatin(FOLFOX),while the second-line regimen involves 5-FU and leucovorin combined with irinotecan(FOLFIRI)for metastatic CRC(mCRC)in China[1].展开更多
文摘With the development of mid-infrared (MIR) photoelectric devices, mid-infrared spectroscopy has become one of the important methods for non-invasive detection of blood glucose. The mid-infrared region (4000 - 400 cm<sup>-1</sup>) has the well-known fingerprint region (1200 - 800 cm<sup>-1</sup>) of glucose, which has clearer characteristic absorption peaks and better specificity. There is a lot of molecular information about glucose in the MIR. The non-invasive detection of blood glucose by mid-infrared spectroscopy needs to achieve certain accuracy, and the quantitative model is an important factor affecting the accuracy of glucose detection. In this paper, the samples of imitation solution containing only glucose and the samples of imitation mixed solution are taken as the research objects, and the mid-infrared spectral data of the samples are collected. The full spectrum partial least squares Regression (PLSR) model, SNV + Ctr-PLSR model, MSC + Ctr-PLSR model, and convolutional neural networks (CNN) model of 3000 - 900 cm<sup>-1</sup> band were constructed. Full spectrum PLS model and CNN model of 1200 - 900 cm<sup>-1</sup> band were constructed. The experimental results show that the optimal model of the two bands is CNN, then the correlation coefficient of prediction set (Rp) of 3000 - 900 cm<sup>-1</sup> band is 0.95, and the root mean square error of pre-diction set (RMSEP) value is 22.10. The Rp of 1200 - 900 cm<sup>-1</sup> band is 0.95, and the RMSEP value is 22.54. The research results show that CNN is a promising method, which has higher accuracy than PLSR, and is especially suitable for modeling human complex environment. In addition, the study provides a theoretical and practical basis for CNN in feature selection and model interpretation.
文摘Whether in the monitoring of critically ill patients such as shock, respiratory failure, brain injury, or in major anesthesia surgeries, it is necessary to evaluate the patient’s pO<sub>2</sub> and pH. An optical fiber sensor presented is capable of monitoring the presence of oxygen partial pressure (pO<sub>2</sub>) and pH in the real-time. The sensor is based on fluorescence sensing of polymer immobilized in the oxygen/pH-sensitive membranes and covalently attached to the optical fiber probe. The design of this sensor uses LED as light source, which is an excitation light source, inducing specific wavelengths of fluorescence on the oxygen/pH-sensitive membrane. The intensity and lifetime of fluorescence are related to the pO<sub>2</sub> and pH. So the pO<sub>2</sub> and pH can be measured by the relationship between the pO<sub>2</sub>/pH values and the intensity and lifetime of fluorescence. The signal conditioning system based on DSP and STM32 was used to store and process data, and display test values. The response of the sensor for pO<sub>2</sub> and pH monitoring with nitrogen (N<sub>2</sub>) as a balancing gas in the laboratory was performed. Finally, the oxygen/pH sensing scheme presented in this work is intended for using in biological, medical and environmental applications.
文摘When a proton reduction cocatalyst is loaded on an n-type semiconductor for photocatalytic overall water splitting(POWS),the location of water oxidation sites is generally considered at the surface of the semiconductor due to upward band-bending of n-type semiconductor which may ease the transfer of the photogenerated holes to the surface.However,this is not the case for Pt/SrTiO_(3),a model semiconductor based photocatalyst for POWS.It was found that the photogenerated holes are more readily accumulated at the interface between Pt cocatalyst and SrTiO_(3) photocatalyst as probed by photo-oxidative deposition of PbO_(2),indicating that the water oxidation sites are located at the interface between Pt and SrTiO_(3).Electron paramagnetic resonance and scanning transmission electron microscope studies suggest that the interfacial oxygen atoms between Pt and SrTiO_(3) in Pt/SrTiO_(3) after POWS are more readily lost to form oxygen vacancies upon vacuum heat treatment,regardless of Pt loading by photodeposition or impregnation methods,which may serve as additional support for the location of the active sites for water oxidation at the interface.Density functional theory calculations also suggest that the oxygen evolution reaction more readily occurs at the interfacial sites with the lowest overpotential.These experimental and theoretical studies reveal that the more active sites for water oxidation are located at the interface between Pt and SrTiO_(3),rather than on the surface of SrTiO_(3).Hence,the tailor design and control of the interfacial properties are extremely important for the achievement or improvement of the POWS on cocatalyst loaded semiconductor photocatalyst.
基金financially supported by the National Key R&D Program of China under contact No.2017YFA0204804the National Natural Science Foundation of China under contact Nos.21761142018,21473189 and 22088102 for supporting Fundamental Research Center of Artificial Photosynthesis(FRe CAP)。
文摘Understanding the processes of charge generation, transfer and capture is important for the design and synthesis of efficient photocatalysts. In this work, light-induced charge separation and effect of O_(2) on electron transfer processes in SrTiO_(3) were investigated by electron paramagnetic resonance(EPR). It was found that photoinduced electron transfer from O_(2)- to Ti^(4+) produced Ti^(3+) and O- redox radical pairs under vacuum condition. Under oxygen atmosphere, however, surface bound superoxide radicals O_(2)-were formed by electron reduction of adsorbed oxygen at initial photoirradiation stage, and quenched by the reverse electron transfer to Ti^(4+) upon further photoirradiation. Formation of long-lived charge separation associated [Ti^(3+)---O-] species and the reversibility of surface bound superoxide radicals mediating the processes of photogenerated electrons may be accountable for the high activity of SrTiO_(3) in photocatalytic water splitting reaction.
基金supported by the National Natural Science Foundation of China(11871024)。
文摘We consider asymptotic behaviors of the Vlasov-Poisson system with radiation damping in three space dimensions.For any smooth solution with compact support,we prove a sub-linear growth estimate of its velocity support.As a consequence,we derive some new estimates of the charge densities and the electrostatic field in this situation.
基金Key Research and Development Program of Shandong Province of China,Grant/Award Number:2017CXZC1206National Natural Science Foundation of China,Grant/Award Number:81874224+1 种基金Academic promotion program of Shandong First Medical University,China,Grant/Award Number:2019LJ004Key Research and Development Program of Shandong Province,Grant/Award Numbers:2021LCZX04,2021SFGC0501。
文摘Background:Concurrent chemoradiotherapy(CCRT)is the standard treatment for locally advanced esophageal squamous cell carcinoma(ESCC).However,the optimal radiotherapy regimen,particularly in terms of total dose and planned range of irradiation field,remains unclear.This phase III clinical trial aimed to compare the survival benefits between different radiation doses and different target fields.Methods:This trial compared two aspects of radiation treatment,total dose and field,using a two-by-two factorial design.The high-dose(HD)group received 59.4 Gy radiation,and the standard-dose(SD)group received 50.4 Gy.The involved field irradiation(IFI)group and elective nodal irradiation(ENI)group adopted different irradiation ranges.The participants were assigned to one of the four groups(HD+ENI,HD+IFI,SD+ENI and SD+IFI).The primary endpoint was overall survival(OS),and the secondary endpoints included progressionfree survival(PFS).The synergy indexwas used to measure the interaction effect between dose and field.Results:The interaction analysis did not reveal significant synergistic effects between the dose and irradiation field.In comparison to the target field,patients in IFI or ENI showed similar OS(hazard ratio[HR]=0.99,95%CI:0.80-1.23,p=0.930)and PFS(HR=1.02,95%CI:0.82–1.25).TheHDtreatment did not show significantly prolonged OS compared with SD(HR=0.90,95%CI:0.72–1.11,p=0.318),but it suggested improved PFS(25.2 months to 18.0 months).Among the four groups,the HD+IFI group presented the best survival,while the SD+IFI group had the worst prognosis.No significant difference in the occurrence of severe adverse events was found in dose or field comparisons.Conclusions:IFI demonstrated similar treatment efficacy to ENI in CCRT of ESCC.The HD demonstrated improved PFS,but did not significantly improve OS.The dose escalation based on IFI(HD+IFI)showed better therapeutic efficacy than the current recommendation(SD+ENI)and is worth further validation.
基金supported by the National Key Research and Development Program of China(2021YFC2300103)the National Natural Science Foundation of China(U21A20384 and 82072293)+1 种基金the Natural Science Foundation of Hunan Province,China(2022JJ30692)the China Postdoctoral Science Foundation(2023M731520).
文摘The ORF9b protein,derived from the nucleocapsid’s open-reading frame in both SARS-CoV and SARS-CoV-2,serves as an accessory protein crucial for viral immune evasion by inhibiting the innate immune response.Despite its significance,the precise regulatory mechanisms underlying its function remain elusive.In the present study,we unveil that the ORF9b protein of SARS-CoV-2,including emerging mutant strains like Delta and Omicron,can undergo ubiquitination at the K67 site and subsequent degradation via the proteasome pathway,despite certain mutations present among these strains.Moreover,our investigation further uncovers the pivotal role of the translocase of the outer mitochondrial membrane 70(TOM70)as a substrate receptor,bridging ORF9b with heat shock protein 90 alpha(HSP90α)and Cullin 5(CUL5)to form a complex.Within this complex,CUL5 triggers the ubiquitination and degradation of ORF9b,acting as a host antiviral factor,while HSP90αfunctions to stabilize it.Notably,treatment with HSP90 inhibitors such as GA or 17-AAG accelerates the degradation of ORF9b,leading to a pronounced inhibition of SARS-CoV-2 replication.Single-cell sequencing data revealed an up-regulation of HSP90αin lung epithelial cells from COVID-19 patients,suggesting a potential mechanism by which SARS-CoV-2 may exploit HSP90αto evade the host immunity.Our study identifies the CUL5-TOM70-HSP90αcomplex as a critical regulator of ORF9b protein stability,shedding light on the intricate host–virus immune response dynamics and offering promising avenues for drug development against SARS-CoV-2 in clinical settings.
文摘We have designed and synthesized NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋. magnetic nano- phosphors with combined dual-mode downconversion （DC） and upconversion （UC） photoluminescence upon 800 run excitation. Hexagonal-phase NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋ nanocrystals （NCs） with an average size of 21 nm were synthesized using a solvothermal approach. Nd^3＋, Yb^3＋, Tm^3＋ triple-doped NaGdF4 NCs exhibit a broad range of photoluminescence peaks covering a near infrared first/second window （860-900, 1,000, and 1,060 nm）, and visible emission including blue （475 nm）, green （520 and 542 nm） and yellow （587 nm） after excitation at 800 nm. A mechanism involving circulation of energy over Gd^3＋ sublattices as bridge ions and final trapping by the initial activator ions （Nd^3＋） has been proposed. Penetration depth studies indicate that NIR emission is easily detected even at a large tissue thickness of 10 mm. These paramagnetic nanophosphors demonstrate a large magnetization value of 1.88 emu/g at 20 kOe and longitudinal relaxivity value of 1.2537 mM-1.S-1 as a Tl-weighted magnetic resonance imaging contrast agent. These NaGdF4：Nd^3＋, Yb^3＋ Tm^3＋ NCs are promising for applications in biological and magnetic resonance imaging.
基金supported by the National Natural Science Foundation of C@hina (810701750)
文摘We present a ballistocardiogram(BCG)measurement system for obtaining the BCG signal.The performance of the BCG measurement system was tested,including the dynamic response frequency of the platform(32 Hz with a 75 kg load),and the signal to noise ratio of the system(minimum 23 dB).Factors that could influence BCG recording during measurement were investigated by collecting data from 48 healthy subjects(28 males and 20females).The basic features of the BCG signal,such as the amplitude and time interval,were extracted,and differences by gender were analyzed.A correlation between the IJ amplitude(amplitude difference between I-and J-peak)and the respiration phase was found(R2=0.49).The BCG signals for both sitting(SiBCG)and standing(StBCG)postures were obtained using this system.These showed that the StBCG amplitudes were larger than those of SiBCG but there was no significant difference in the time intervals.The robustness of our system was verified,and its potential for non-invasive cardiac activity monitoring was demonstrated.
文摘Background:To analyze the clinical features of brain tumor-related epilepsy(BTRE)and explore the factors influencing the identification of epilepsy-associated tumor(EAT),in order to advance the clinical understanding of BTRE and EAT.Methods:Intracranial tumor origin and location as well as the type of epilepsy were retrospectively reviewed in 153 BTRE patients.The patients were further divided into the EAT and non-EAT groups,and comparisons were made for age,sex,tumor origin and location,and epilepsy type between the two groups.Results:The 153 BTRE patients were divided into 78 cases with primary intracranial tumor and 75 cases with tumor originating from extracranial metastasis,according to the origin of tumor.According to the location of tumor,116 cases had tumor lesions located in the brain parenchyma,and 37 cases had tumor lesions located in the meninges.Further,in the group with a brain parenchyma location,77 cases had single lobular involvement,and 39 cases had multiple-lobular involvement;84 cases had tumor lesions located in one hemisphere and 32 cases in both hemispheres.According to the type of epilepsy,92 cases had generalized seizures,and 61 cases had focal seizures.The type of epilepsy did not significantly correlate with the origin of intracranial tumor,the location of tumor lesions(in brain parenchyma or meninges)(P>0.05),or the hemispherical location(in one or two hemispheres)of lesions(P>0.05),but was significantly related with the lobular localization of lesions(P<0.05).The 153 cases of BTRE consisted of 87 EAT and 66 non-EAT,with significant differences in the origin,location and type(being glioma/non-glioma)of tumor.Logistic regression analysis showed that the type of tumor(i.e.whether being glioma)served as an independent factor for EAT identification;the lower the World Health Organization grade of glioma,the more likely the EAT is to be diagnosed(P<0.05).Conclusion:The majority of BTRE patients in this study had tumors located in the brain parenchyma.In addition,the patients with generalized seizures outnumbered those with focal seizures,and the type of epilepsy was correlated with the lobular location of tumor lesions.The EATs are mostly low-grade gliomas.
文摘Primary chemotherapy options for colorectal cancer(CRC)involve four key drugs:fluorouracils(5-FU),oxaliplatin,irinotecan and raltitrexed.The first-line regimen consists of 5-FU and leucovorin combined with oxaliplatin(FOLFOX),while the second-line regimen involves 5-FU and leucovorin combined with irinotecan(FOLFIRI)for metastatic CRC(mCRC)in China[1].
