Objective:To examine whether exposure of mouse neuronal cells to radiofrequency fields used in mobile communication devices can induce stress in endoplasmic reticulum(ER)and activate unfolded protein response(UPR).Met...Objective:To examine whether exposure of mouse neuronal cells to radiofrequency fields used in mobile communication devices can induce stress in endoplasmic reticulum(ER)and activate unfolded protein response(UPR).Methods:HT22 mouse hippocampus neuronal cells were exposed to continuous wave 900 MHz radiofrequency fields(RF)at 120μW/cm2 power intensity for 4 h/d for 5 consecutive days.The positive control cells were irradiated with 4 Gy of 60Coγ-rays at a dose rate of 0.5 Gy/min(GR).Twenty-four hours after the last exposure,cells were collected,and the expressions of sensor transmembrane proteins were detected using Western blot analysis.Results:The expression levels of Ire1,PERK,p-IRE1 and p-PERK,GRP78 and CHOP proteins were detected.There were no statistically significant differences in the expression levels of IRE1 and PERK proteins in control(CT),sham(SH)-,RF-and GR-exposed cells(P<0.05).The phosphorylated protein levels of p-IRE1 and p-PERK were significantly increased in cells exposed to RF and GR(P<0.05).The expression levels of GRP78 and CHOP were significantly increased in RF-and GR-exposed cells compared to CT and SH-exposed cells(P<0.05).Cells treated with 1μg/ml TM for 24 h showed significantly increased expression levels of GRP78 and CHOP proteins compared to controls(P<0.05).In the presence of 2 mmol/L PBA,TM-induced increased levels of GRP78 and CHOP proteins were reduced(P<0.05).Conclusions:The exposure of non-ionizing 900 MHz RF was able to cause stress in HT22 mouse neuronal cells and activated UPR in ER.Since UPR plays an important role in both cell survival(when UPR is mitigated)and apoptosis/death(under unresolvable stress conditions),further studies are required to determine the fate of the cells exposed to RF.展开更多
Objective The present study aimed to test whether exposure to radiofrequency electromagnetic fields （RF-EMF） emitted by mobile phone base stations may have effects on salivary alpha-amylase, immunoglobulin A （IgA）...Objective The present study aimed to test whether exposure to radiofrequency electromagnetic fields （RF-EMF） emitted by mobile phone base stations may have effects on salivary alpha-amylase, immunoglobulin A （IgA）, and cortisol levels. Methods Fifty seven participants were randomly allocated to one of three different experimental scenarios （22 participants to scenario 1, 26 to scenario 2, and 9 to scenario 3）. Each participant went through five 50-minute exposure sessions. The main RF-EMF source was a GSM-900-MHz antenna located at the outer wall of the building. In scenarios 1 and 2, the first, third, and fifth sessions were ＂low＂ （median power flux density 5.2 μW/m^2） exposure. The second session was ＂high＂ （2126.8 μW/m^2）, and the fourth session was ＂medium＂ （153.6 μW/m^2） in scenario 1, and vice versa in scenario 2. Scenario 3 had four ＂low＂ exposure conditions, followed by a ＂high＂ exposure condition. Biomedical parameters were collected by saliva samples three times a session. Exposure levels were created by shielding curtains. Results In scenario 3 from session 4 to session 5 （from ＂low＂ to ＂high＂ exposure）, an increase of cortisol was detected, while in scenarios 1 and 2, a higher concentration of alpha-amylase related to the baseline was identified as compared to that in scenario 3. IgA concentration was not significantly related to the exposure. Conclusions RF-EMF in considerably lower field densities than ICNIRP-gnidelines may influence certain psychobiological stress markers.展开更多
Retinal ganglion cells(RGCs) exhibit adaptive changes in response to sustained light stimulation,which include decrease in firing rate, tendency to shrink in receptive field(RF) size and reduction in synchronized acti...Retinal ganglion cells(RGCs) exhibit adaptive changes in response to sustained light stimulation,which include decrease in firing rate, tendency to shrink in receptive field(RF) size and reduction in synchronized activities. Gamma-aminobutyric acid-ergic(GABAergic) pathway is an important inhibitory pathway in retina.In the present study, the effects of GABAergic pathway on the contrast adaptation process of bullfrog RGCs were studied using multi-electrode recording technique. It was found that the application of bicuculline(BIC), a gamma-aminobutyric acid A(GABAA) receptor antagonist, caused a number of changes in the RGCs' response characteristics, including attenuation in adaptation-dependent firing rate decrease and the adaptation-dependent weakening in synchronized activities between adjacent neuron-pairs, whereas intensified the adaptation-dependent RF size shrinkage. These results suggest that GABAAreceptors are involved in the modulation of the firing activity and synchronized activities in contrast adaptation process of the RGCs, whereas the adaptation-related RF property changes involve more complicated mechanisms.展开更多
目的准确快速的火焰检测技术在早期火灾预警中具有重要的实际应用价值。为了降低伪火类物体引起的误警率以及早期小火焰的漏检率,本文设计了一种结合感受野(receptive field,RF)模块与并联区域建议网络(parallel region proposal networ...目的准确快速的火焰检测技术在早期火灾预警中具有重要的实际应用价值。为了降低伪火类物体引起的误警率以及早期小火焰的漏检率,本文设计了一种结合感受野(receptive field,RF)模块与并联区域建议网络(parallel region proposal network,PRPN)的卷积神经网络(receptive field and parallel region proposal convolutional neural network,R-PRPNet)用于火焰检测。方法R-PRPNet主要由特征提取模块、并联区域建议网络和分类器3部分组成。特征提取模块在MobileNet卷积层的基础上,通过嵌入感受野RF模块扩大感受野捕获更丰富的上下文信息,从而提取更具鉴别性的火焰特征,降低伪火类物体引起的误警率;并联区域建议网络与特征提取模块后端的多尺度采样层连接,使用3×3和5×5的全卷积进一步拓宽多尺度锚点的感受野宽度,提升PRPN对不同尺度火焰的检测能力,解决火灾发生初期的小火焰漏检问题;分类器由softmax和smooth L1分别实现分类与回归。在R-PRPNet训练过程中,将伪火类物体作为负样本进行负样本微调,以更好区分伪火类物体。结果在包括室内、建筑物、森林和夜晚等场景火焰数据以及包括灯光、晚霞、火烧云和阳光等伪火类数据的自建数据集上对所提方法进行测试,在火焰检测任务中,准确度为98.07%,误警率为4.2%,漏检率为1.4%。消融实验结果表明,R-PRPNet较基线网络在漏检率和误警率上分别降低了4.9%和21.72%。与传统火焰检测方法相比,R-PRPNet在各项指标上均优于边缘梯度信息和聚类等方法。性能较几种目标检测算法有所提升,其中相较于YOLOX-L,误警率和漏检率分别降低了22.2%和5.2%。此外,本文在不同场景火焰下进行测试,都有较稳定的表现。结论本文方法有效降低了火焰检测中的误警率和漏检率,并可以满足火焰检测的实时性和准确性需求。展开更多
基金This research is supported by funding from the National Natural Science Foundation of China(Grant No.81373025).
文摘Objective:To examine whether exposure of mouse neuronal cells to radiofrequency fields used in mobile communication devices can induce stress in endoplasmic reticulum(ER)and activate unfolded protein response(UPR).Methods:HT22 mouse hippocampus neuronal cells were exposed to continuous wave 900 MHz radiofrequency fields(RF)at 120μW/cm2 power intensity for 4 h/d for 5 consecutive days.The positive control cells were irradiated with 4 Gy of 60Coγ-rays at a dose rate of 0.5 Gy/min(GR).Twenty-four hours after the last exposure,cells were collected,and the expressions of sensor transmembrane proteins were detected using Western blot analysis.Results:The expression levels of Ire1,PERK,p-IRE1 and p-PERK,GRP78 and CHOP proteins were detected.There were no statistically significant differences in the expression levels of IRE1 and PERK proteins in control(CT),sham(SH)-,RF-and GR-exposed cells(P<0.05).The phosphorylated protein levels of p-IRE1 and p-PERK were significantly increased in cells exposed to RF and GR(P<0.05).The expression levels of GRP78 and CHOP were significantly increased in RF-and GR-exposed cells compared to CT and SH-exposed cells(P<0.05).Cells treated with 1μg/ml TM for 24 h showed significantly increased expression levels of GRP78 and CHOP proteins compared to controls(P<0.05).In the presence of 2 mmol/L PBA,TM-induced increased levels of GRP78 and CHOP proteins were reduced(P<0.05).Conclusions:The exposure of non-ionizing 900 MHz RF was able to cause stress in HT22 mouse neuronal cells and activated UPR in ER.Since UPR plays an important role in both cell survival(when UPR is mitigated)and apoptosis/death(under unresolvable stress conditions),further studies are required to determine the fate of the cells exposed to RF.
基金funded by the Land Salzburg Federal Government,Science Department,and Mr.Daniell Porsche,Chairman of the Paracelsus-School at St.Jakob am Thurn,Salzburg,Austria.
文摘Objective The present study aimed to test whether exposure to radiofrequency electromagnetic fields （RF-EMF） emitted by mobile phone base stations may have effects on salivary alpha-amylase, immunoglobulin A （IgA）, and cortisol levels. Methods Fifty seven participants were randomly allocated to one of three different experimental scenarios （22 participants to scenario 1, 26 to scenario 2, and 9 to scenario 3）. Each participant went through five 50-minute exposure sessions. The main RF-EMF source was a GSM-900-MHz antenna located at the outer wall of the building. In scenarios 1 and 2, the first, third, and fifth sessions were ＂low＂ （median power flux density 5.2 μW/m^2） exposure. The second session was ＂high＂ （2126.8 μW/m^2）, and the fourth session was ＂medium＂ （153.6 μW/m^2） in scenario 1, and vice versa in scenario 2. Scenario 3 had four ＂low＂ exposure conditions, followed by a ＂high＂ exposure condition. Biomedical parameters were collected by saliva samples three times a session. Exposure levels were created by shielding curtains. Results In scenario 3 from session 4 to session 5 （from ＂low＂ to ＂high＂ exposure）, an increase of cortisol was detected, while in scenarios 1 and 2, a higher concentration of alpha-amylase related to the baseline was identified as compared to that in scenario 3. IgA concentration was not significantly related to the exposure. Conclusions RF-EMF in considerably lower field densities than ICNIRP-gnidelines may influence certain psychobiological stress markers.
基金the National Natural Science Foundation of China(No.61375114)
文摘Retinal ganglion cells(RGCs) exhibit adaptive changes in response to sustained light stimulation,which include decrease in firing rate, tendency to shrink in receptive field(RF) size and reduction in synchronized activities. Gamma-aminobutyric acid-ergic(GABAergic) pathway is an important inhibitory pathway in retina.In the present study, the effects of GABAergic pathway on the contrast adaptation process of bullfrog RGCs were studied using multi-electrode recording technique. It was found that the application of bicuculline(BIC), a gamma-aminobutyric acid A(GABAA) receptor antagonist, caused a number of changes in the RGCs' response characteristics, including attenuation in adaptation-dependent firing rate decrease and the adaptation-dependent weakening in synchronized activities between adjacent neuron-pairs, whereas intensified the adaptation-dependent RF size shrinkage. These results suggest that GABAAreceptors are involved in the modulation of the firing activity and synchronized activities in contrast adaptation process of the RGCs, whereas the adaptation-related RF property changes involve more complicated mechanisms.
文摘目的准确快速的火焰检测技术在早期火灾预警中具有重要的实际应用价值。为了降低伪火类物体引起的误警率以及早期小火焰的漏检率,本文设计了一种结合感受野(receptive field,RF)模块与并联区域建议网络(parallel region proposal network,PRPN)的卷积神经网络(receptive field and parallel region proposal convolutional neural network,R-PRPNet)用于火焰检测。方法R-PRPNet主要由特征提取模块、并联区域建议网络和分类器3部分组成。特征提取模块在MobileNet卷积层的基础上,通过嵌入感受野RF模块扩大感受野捕获更丰富的上下文信息,从而提取更具鉴别性的火焰特征,降低伪火类物体引起的误警率;并联区域建议网络与特征提取模块后端的多尺度采样层连接,使用3×3和5×5的全卷积进一步拓宽多尺度锚点的感受野宽度,提升PRPN对不同尺度火焰的检测能力,解决火灾发生初期的小火焰漏检问题;分类器由softmax和smooth L1分别实现分类与回归。在R-PRPNet训练过程中,将伪火类物体作为负样本进行负样本微调,以更好区分伪火类物体。结果在包括室内、建筑物、森林和夜晚等场景火焰数据以及包括灯光、晚霞、火烧云和阳光等伪火类数据的自建数据集上对所提方法进行测试,在火焰检测任务中,准确度为98.07%,误警率为4.2%,漏检率为1.4%。消融实验结果表明,R-PRPNet较基线网络在漏检率和误警率上分别降低了4.9%和21.72%。与传统火焰检测方法相比,R-PRPNet在各项指标上均优于边缘梯度信息和聚类等方法。性能较几种目标检测算法有所提升,其中相较于YOLOX-L,误警率和漏检率分别降低了22.2%和5.2%。此外,本文在不同场景火焰下进行测试,都有较稳定的表现。结论本文方法有效降低了火焰检测中的误警率和漏检率,并可以满足火焰检测的实时性和准确性需求。
