The purpose of this contribution is to review our current understanding of the source and biochemistry of the circadian efferent input to the eyes of the American horseshoe crab Limuluspolyphemus and the impact of thi...The purpose of this contribution is to review our current understanding of the source and biochemistry of the circadian efferent input to the eyes of the American horseshoe crab Limuluspolyphemus and the impact of this input on the structure, physiology and biochemistry of Limulus eyes. Special emphasis is given to the role of the biogenic amine octopamine and bio- chemical cascades it activates in the eyes. In addition to reviewing published data, we present new data showing that octopamine elevates cAMP levels in Limulus lateral eyes, and we partially characterize the pharmacology of the receptors involved in this response. We also present new data showing that octopamine regulates gene expression in Limulus lateral eyes by activating a cAMP cascade展开更多
Activation of seismic activity in the Vrancha area, in the Black Sea region resulted in considerable activation of landslides and in increasing of landslide hazard in earthquake-prone areas of Ukraine. Totally about 2...Activation of seismic activity in the Vrancha area, in the Black Sea region resulted in considerable activation of landslides and in increasing of landslide hazard in earthquake-prone areas of Ukraine. Totally about 23,000 landslides were identified in the territory of Ukraine. Experimental and analytical studies of slumps in the Central Livadia landslide system were carried out with the aid of the ZSUV monitoring system. Experimental data were obtained concerning impact of natural seismic factors on the Central Livadia landslide system and on the Palace itself. The South-East wing of the Livadia Palace continuously vibrates relative to a certain midposition. The increase of the amplitude of the faqade deviation from the midposition may be caused by activation of slopes as a result of additional subsidence and ground water rise due to local earthquakes in the Black Sea and because of some other factors.展开更多
The impact of aerosols on the climate and atmospheric environment depends on the water uptake ability of particles;namely,hygroscopic growth and activation into cloud condensation nuclei(CCN).The size-resolved activat...The impact of aerosols on the climate and atmospheric environment depends on the water uptake ability of particles;namely,hygroscopic growth and activation into cloud condensation nuclei(CCN).The size-resolved activation ratios(SRAR),characterizing the fraction of aerosol particles that act as CCN at different particle sizes and supersaturations,can be measured using a combination of differential mobility analyzers(DMA) and particle counters.DMA-based measurements are influenced by the multiply charged particles and the quasi-mono-dispersed particles(effect of DMA transfer function) selected for each prescribed particle size.A theoretical study,assuming different particle number size distributions and hygroscopicity of aerosols,is performed to study the effects of the DMA transfer function and multiple charging on the measured SRAR and the derived hygroscopicity.Results show that the raw SRAR can be significantly skewed and hygroscopicity may be highly biased from the true value if the data are not corrected.The effect of the transfer function is relatively small and depends on the sample to sheath flow ratio.Multiply charged particles,however,can lead to large biases of the SRAR.These results emphasize that the inversion algorithm,which is used to correct the effects of the DMA transfer function and multiple charging,is necessary for accurate measurement of the SRAR.展开更多
The differentiation status of neuroblastoma （NB） strongly correlates with its clinical outcomes; however, the molecular mechanisms driving maintenance of sternness and differentiation remain poorly understood. Here,...The differentiation status of neuroblastoma （NB） strongly correlates with its clinical outcomes; however, the molecular mechanisms driving maintenance of sternness and differentiation remain poorly understood. Here, we show that plant homeodomain finger-containing protein 20 （PHF20） functions as a critical epigenetic regulator in sustaining stem cell-like phenotype of NB by using CRISPR/Casg-based targeted knockout （KO） for high-throughput screening of gene function in NB cell differentiation. The expression of PHF20 in NB was significantly associated with high aggressiveness of the tumor and poor outcomes for NB patients. Deletion of PHF20 inhibited NB cell proliferation, invasive migration, and stem ceU-Uke traits. Mechanistically, PHF20 interacts with poly（ADP-ribose） polymerase 1 （PARP1） and directly binds to promoter regions of octamer-binding transcription factor 4 （OCT4） and sex determining region Y-box 2 （SOX2） to modulate a histone mark associated with active transcription, trimethylation of lysine 4 on histone H3 protein subunit （H3K4me3）. Overexpression of OCT4 and SOX2 restored growth and progression of PHF20 KO tumor cells. Consistently, OCT4 and SOX2 protein levels in clinical NB specimens were positively correlated with PHF20 expression. Our results establish PHF20 as a key driver of NB stem cell-like properties and aggressive behaviors, with implications for prognosis and therapy.展开更多
New genes are drivers of evolutionary innovation and phenotypic evolution. Expression of new genes in early development raises the possibility that new genes could originate and be recruited for functions in embryonic...New genes are drivers of evolutionary innovation and phenotypic evolution. Expression of new genes in early development raises the possibility that new genes could originate and be recruited for functions in embryonic development, but this remains undocu- mented. Here, based on temporal gene expression at different developmental stages in Xenopus tropicolis, we found that young protein-coding genes were significantly enriched for expression in developmental stages occurring after the midblastula trans- ition （MBT）, and displayed a decreasing trend in abundance in the subsequent stages after MBT. To complement the finding, we demonstrate essential functional attributes of a young orphan gene, named as Fog2, in morphological development. Our data indicate that new genes could originate after MBT and be recruited for functions in embryonic development, and thus provide insights for better understanding of the origin, evolution, and function of new genes.展开更多
The activation coefficient equations in the"activation criterion of pre-existing weakness"are relatively complex and not easy to apply to specific applications.The relative activity of pre-existing weaknesse...The activation coefficient equations in the"activation criterion of pre-existing weakness"are relatively complex and not easy to apply to specific applications.The relative activity of pre-existing weaknesses is often critical in geological analysis.The Mohr circle can be used only in two-dimensional stress analysis.By applying the"activation criterion of pre-existing weakness"and combining it with numerical analysis,we establish the correspondence between the pole(n,n)of a pre-existing weakness plane and its orientation in"Mohr space".As a result,the normal stress(n)and shear stress(n)of a pre-existing weakness plane can be readily expressed in Mohr space.Furthermore,we introduce the method and procedures for predicting the activation and relative activation of pre-existing weaknesses in Mohr space.Finally,we apply the Mohr space method and compare the predictions to sandbox modeling results and 3D seismic data.The results show that Mohr space can be used in stress analysis to estimate the activation of a pre-existing weakness in any triaxial stress state.展开更多
基金supported by grants from the National Science Foundation (NSF)the Whitehall Foundation and the Whimey Laboratory
文摘The purpose of this contribution is to review our current understanding of the source and biochemistry of the circadian efferent input to the eyes of the American horseshoe crab Limuluspolyphemus and the impact of this input on the structure, physiology and biochemistry of Limulus eyes. Special emphasis is given to the role of the biogenic amine octopamine and bio- chemical cascades it activates in the eyes. In addition to reviewing published data, we present new data showing that octopamine elevates cAMP levels in Limulus lateral eyes, and we partially characterize the pharmacology of the receptors involved in this response. We also present new data showing that octopamine regulates gene expression in Limulus lateral eyes by activating a cAMP cascade
文摘Activation of seismic activity in the Vrancha area, in the Black Sea region resulted in considerable activation of landslides and in increasing of landslide hazard in earthquake-prone areas of Ukraine. Totally about 23,000 landslides were identified in the territory of Ukraine. Experimental and analytical studies of slumps in the Central Livadia landslide system were carried out with the aid of the ZSUV monitoring system. Experimental data were obtained concerning impact of natural seismic factors on the Central Livadia landslide system and on the Palace itself. The South-East wing of the Livadia Palace continuously vibrates relative to a certain midposition. The increase of the amplitude of the faqade deviation from the midposition may be caused by activation of slopes as a result of additional subsidence and ground water rise due to local earthquakes in the Black Sea and because of some other factors.
基金supported by the National Natural Science Foundation of China (NSFC) (Grant Nos.41205098 and 41305114)the "Strategic Priority Research Program" of the Chinese Academy of Sciences (Grant No.XDA05100000)
文摘The impact of aerosols on the climate and atmospheric environment depends on the water uptake ability of particles;namely,hygroscopic growth and activation into cloud condensation nuclei(CCN).The size-resolved activation ratios(SRAR),characterizing the fraction of aerosol particles that act as CCN at different particle sizes and supersaturations,can be measured using a combination of differential mobility analyzers(DMA) and particle counters.DMA-based measurements are influenced by the multiply charged particles and the quasi-mono-dispersed particles(effect of DMA transfer function) selected for each prescribed particle size.A theoretical study,assuming different particle number size distributions and hygroscopicity of aerosols,is performed to study the effects of the DMA transfer function and multiple charging on the measured SRAR and the derived hygroscopicity.Results show that the raw SRAR can be significantly skewed and hygroscopicity may be highly biased from the true value if the data are not corrected.The effect of the transfer function is relatively small and depends on the sample to sheath flow ratio.Multiply charged particles,however,can lead to large biases of the SRAR.These results emphasize that the inversion algorithm,which is used to correct the effects of the DMA transfer function and multiple charging,is necessary for accurate measurement of the SRAR.
基金This work was supported by grants from the National Natural Science Foundation of China （81572766 and 31771630）, the National Key Research and Development Program of China （2017YFA0103800）, Guangdong Innovative and Entrepreneurial Research Team Program （2016ZT06S029）, Guangdong Natural Science Foundation （2016A030313215 and 2016A030313238）, SYSU Young Teachers Training Program （16YKZD14） and grants （CA101795 and IU54CA210181） from U.S. National Cancer Institute, National Institutes of Health （NIH）, DOD （W81XWH-16- 1-0417）, and CPRIT （DP150099, RP170537, and RP150611）.
文摘The differentiation status of neuroblastoma （NB） strongly correlates with its clinical outcomes; however, the molecular mechanisms driving maintenance of sternness and differentiation remain poorly understood. Here, we show that plant homeodomain finger-containing protein 20 （PHF20） functions as a critical epigenetic regulator in sustaining stem cell-like phenotype of NB by using CRISPR/Casg-based targeted knockout （KO） for high-throughput screening of gene function in NB cell differentiation. The expression of PHF20 in NB was significantly associated with high aggressiveness of the tumor and poor outcomes for NB patients. Deletion of PHF20 inhibited NB cell proliferation, invasive migration, and stem ceU-Uke traits. Mechanistically, PHF20 interacts with poly（ADP-ribose） polymerase 1 （PARP1） and directly binds to promoter regions of octamer-binding transcription factor 4 （OCT4） and sex determining region Y-box 2 （SOX2） to modulate a histone mark associated with active transcription, trimethylation of lysine 4 on histone H3 protein subunit （H3K4me3）. Overexpression of OCT4 and SOX2 restored growth and progression of PHF20 KO tumor cells. Consistently, OCT4 and SOX2 protein levels in clinical NB specimens were positively correlated with PHF20 expression. Our results establish PHF20 as a key driver of NB stem cell-like properties and aggressive behaviors, with implications for prognosis and therapy.
基金This work was supported by the National Natural Science Foundation of China （31671325 and 31271339）. N.O.O. thanks the CAS-TWAS President＇s Fellowship Program for Doctoral Candidates for support.
文摘New genes are drivers of evolutionary innovation and phenotypic evolution. Expression of new genes in early development raises the possibility that new genes could originate and be recruited for functions in embryonic development, but this remains undocu- mented. Here, based on temporal gene expression at different developmental stages in Xenopus tropicolis, we found that young protein-coding genes were significantly enriched for expression in developmental stages occurring after the midblastula trans- ition （MBT）, and displayed a decreasing trend in abundance in the subsequent stages after MBT. To complement the finding, we demonstrate essential functional attributes of a young orphan gene, named as Fog2, in morphological development. Our data indicate that new genes could originate after MBT and be recruited for functions in embryonic development, and thus provide insights for better understanding of the origin, evolution, and function of new genes.
基金supported by the China Major National Science & Technology Program of Oil and Gas (Grant Nos. 2011ZX05023-004-012, 2011ZX05006-006-02-01)the National Natural Science Foundation of China (Grant Nos. 41272160, 40772086)
文摘The activation coefficient equations in the"activation criterion of pre-existing weakness"are relatively complex and not easy to apply to specific applications.The relative activity of pre-existing weaknesses is often critical in geological analysis.The Mohr circle can be used only in two-dimensional stress analysis.By applying the"activation criterion of pre-existing weakness"and combining it with numerical analysis,we establish the correspondence between the pole(n,n)of a pre-existing weakness plane and its orientation in"Mohr space".As a result,the normal stress(n)and shear stress(n)of a pre-existing weakness plane can be readily expressed in Mohr space.Furthermore,we introduce the method and procedures for predicting the activation and relative activation of pre-existing weaknesses in Mohr space.Finally,we apply the Mohr space method and compare the predictions to sandbox modeling results and 3D seismic data.The results show that Mohr space can be used in stress analysis to estimate the activation of a pre-existing weakness in any triaxial stress state.
