In modern wireless communications,digital information is frstly converted to analog signal by a digital-analog convertor,which is then mixed to high-frequency microwave to be transmitted through a series of devices in...In modern wireless communications,digital information is frstly converted to analog signal by a digital-analog convertor,which is then mixed to high-frequency microwave to be transmitted through a series of devices including modulator,mixer,amplifer,flter,and antenna and is fnally received by terminals via a reversed process.Although the wireless communication systems have evolved signifcantly over the past thirty years,the basic architecture has not been challenged.Here,we propose a method to transmit digital information directly via programmable coding metasurface.Since the coding metasurface is composed of‘0’and‘1’digital units with opposite phase responses,the digital information can be directly modulated to the metasurface with certain coding sequences and sent to space under the illumination of feeding antenna.Te information,being modulated in radiation patterns of the metasurface,can be correctly received by multiple receivers distributed in diferent locations.Tis method provides a completely new architecture for wireless communications without using complicated digital-analog convertor and a series of active/passive microwave devices.We build up a prototype to validate the new architecture experimentally,which may fnd promising applications where information security is highly demanded.展开更多
During the past decades,major advances have been made in both the generation and detection of infrared light;however,its efficient wavefront manipulation and information processing still encounter great challenges.Eff...During the past decades,major advances have been made in both the generation and detection of infrared light;however,its efficient wavefront manipulation and information processing still encounter great challenges.Efficient and fast optoelectronic modulators and spatial light modulators are required for mid-infrared imaging,sensing,security screening,communication and navigation,to name a few.However,their development remains elusive,and prevailing methods reported so far have suffered from drawbacks that significantly limit their practical applications.In this study,by leveraging graphene and metasurfaces,we demonstrate a high-performance free-space mid-infrared modulator operating at gigahertz speeds,low gate voltage and room temperature.We further pixelate the hybrid graphene metasurface to form a prototype spatial light modulator for high frame rate single-pixel imaging,suggesting orders of magnitude improvement over conventional liquid crystal or micromirror-based spatial light modulators.This work opens up the possibility of exploring wavefront engineering for infrared technologies for which fast temporal and spatial modulations are indispensable.展开更多
Driven by their potential applications, vectorial optical fields with spatially inhomogeneous states of polarization within the cross section have drawn significant attention recently. This work intends to review some...Driven by their potential applications, vectorial optical fields with spatially inhomogeneous states of polarization within the cross section have drawn significant attention recently. This work intends to review some of the latest development of this rapidly growing field of optics and offer a general overview of the current status of this field in a few areas. Mathematical descriptions of generalized vectorial optical fields are provided along with several special examples. A time-reversal methodology for the creation of a wide variety of exotic optical focal fields with prescribed characteristics within the focal volume is presented. Recently developed methods for the generation of vectorial optical fields that utilize fiber lasers,digital lasers, vectorial optical field generator, metasurfaces or photoalignment liquid crystals are summarized. The interactions of these vectorial optical fields with various micro-and nano-structures are presented and the prospects of their potential applications are discussed. The connection of vectorial optical fields with higher dimensionality in quantum information is summarized.展开更多
Approximately 80% of breast cancers(BC) are estrogen receptor(ER)-positive and thus endocrine therapy(ET) should be considered complementary to surgery in the majority of patients. The advantages of oophorectomy, adre...Approximately 80% of breast cancers(BC) are estrogen receptor(ER)-positive and thus endocrine therapy(ET) should be considered complementary to surgery in the majority of patients. The advantages of oophorectomy, adrenalectomy and hypophysectomy in women with advanced BC have been demonstrated many years ago, and currently ET consist of(1) ovarian function suppression(OFS), usually obtained using gonadotropinreleasing hormone agonists(Gn RHa);(2) selective estrogen receptor modulators or down-regulators(SERMs or SERDs); and(3) aromatase inhibitors(AIs), or a combination of two or more drugs. For patients aged less than 50 years and ER+ BC, there is no conclusive evidence that the combination of OFS and SERMs(i.e., tamoxifen) or chemotherapy is superior to OFS alone. Tamoxifen users exhibit a reduced risk of BC, both invasive and in situ, especially during the first 5 years of therapy, and extending the treatment to 10 years further reduced the risk of recurrences. SERDs(i.e., fulvestrant) are especially useful in the neoadjuvant treatment of advanced BC, alone or in combination with either cytotoxic agents or AIs. There are two types of AIs: type Ⅰ are permanent steroidal inhibitors of aromatase, while type Ⅱ are reversible nonsteroidal inhibitors. Several studies demonstrated the superiority of the third-generation AIs(i.e., anastrozole and letrozole) compared with tamoxifen, and adjuvant therapy with AIs reduces the recurrence risk especially in patients with advanced BC. Unfortunately, some cancers are or became ET-resistant, and thus other drugs have been suggested in combination with SERMs or AIs, including cyclin-dependent kinase 4/6 inhibitors(palbociclib) and mammalian target of rapamycin(m TOR) inhibitors, such as everolimus. Further studies are required to confirm their real usefulness.展开更多
CD44 is highly expressed in human acute myeloid leukemia （AML） cells. Some experiments had shown that it was possible to reverse differentiation blockage in AML cells by CD44 ligation with specific antibodies, indic...CD44 is highly expressed in human acute myeloid leukemia （AML） cells. Some experiments had shown that it was possible to reverse differentiation blockage in AML cells by CD44 ligation with specific antibodies, indicating that CD44 was closely related to the differentiation of leukemia cells. The differentiation of acute promyelocytic leukemia cell line HL-60 cells could be induced by all trans-retinoic acid （ATRA） and hexamethylene bisacetamide （HMBA）, but so far the mechanism was not demonstrated clearly. In the present study, we investigated whether ATRA or HMBA induced the growth arrest of HL-60 cells by down-regulating the expression of CD44. The results indicated that the proliferation of HL-60 cells was obviously inhibited and the differentiation was induced by both ATRA and HMBA. The decreased expression of CD44 and cyclin E mRNA, and the increased expression of p27 and p21 at mRNA levels were observed. Furthermore, there was a negative correlation between the expression of CD44 and p27. It was concluded that ATRA and HMBA played a role in the differentiation induction of HL-60 cells, which was mediated by the down-regulation of CD44, accompanied by down-regulation of cyclin E, and up-regulation of p27 and p21 mRNA. Cellular ＆ Molecular Immunology. 2007;4（1）：59-63.展开更多
Active metasurfaces are emerging as the core of next-generation optical devices with their tunable optical responses and flat-compact topography.Especially for the terahertz band,active metasurfaces have been develope...Active metasurfaces are emerging as the core of next-generation optical devices with their tunable optical responses and flat-compact topography.Especially for the terahertz band,active metasurfaces have been developed as fascinating devices for optical chopping and compressive sensing imaging.However,performance regulation by changing the dielectric parameters of the integrated functional materials exhibits severe limitations and parasitic losses.Here,we introduce a C-shape-split-ring-based phase discontinuity metasurface with liquid crystal elastomer as the substrate for infrared modulation of terahertz wavefront.Line-focused infrared light is applied to manipulate the deflection of the liquid crystal elastomer substrate,enabling controllable and broadband wavefront steering with a maximum output angle change of 22°at 0.68THz.Heating as another control method is also investigated and compared with infrared control.We further demonstrate the performance of liquid crystal elastomer metasurface as a beam steerer,frequency modulator,and tunable beam splitter,which are highly desired in terahertz wireless communication and imaging systems.The proposed scheme demonstrates the promising prospects of mechanically deformable metasurfaces,thereby paving the path for the development of reconfigurable metasurfaces.展开更多
基金The authors acknowledge supports by National Key Research and Development Program of China(2017YFA0700201,2017YFA0700202,and 2017YFA0700203)National Natural Science Foundation of China(61631007,61571117,61501112,61501117,61522106,61731010,61735010,61722106,61701107,and 61701108)111 Project(No.111-2-05).
文摘In modern wireless communications,digital information is frstly converted to analog signal by a digital-analog convertor,which is then mixed to high-frequency microwave to be transmitted through a series of devices including modulator,mixer,amplifer,flter,and antenna and is fnally received by terminals via a reversed process.Although the wireless communication systems have evolved signifcantly over the past thirty years,the basic architecture has not been challenged.Here,we propose a method to transmit digital information directly via programmable coding metasurface.Since the coding metasurface is composed of‘0’and‘1’digital units with opposite phase responses,the digital information can be directly modulated to the metasurface with certain coding sequences and sent to space under the illumination of feeding antenna.Te information,being modulated in radiation patterns of the metasurface,can be correctly received by multiple receivers distributed in diferent locations.Tis method provides a completely new architecture for wireless communications without using complicated digital-analog convertor and a series of active/passive microwave devices.We build up a prototype to validate the new architecture experimentally,which may fnd promising applications where information security is highly demanded.
基金the Los Alamos National Laboratory LDRD ProgramAFOSR under contract no.FA9550-12-0491the AFOSR YIP program under Contract no.FA9550-16-1-0183.
文摘During the past decades,major advances have been made in both the generation and detection of infrared light;however,its efficient wavefront manipulation and information processing still encounter great challenges.Efficient and fast optoelectronic modulators and spatial light modulators are required for mid-infrared imaging,sensing,security screening,communication and navigation,to name a few.However,their development remains elusive,and prevailing methods reported so far have suffered from drawbacks that significantly limit their practical applications.In this study,by leveraging graphene and metasurfaces,we demonstrate a high-performance free-space mid-infrared modulator operating at gigahertz speeds,low gate voltage and room temperature.We further pixelate the hybrid graphene metasurface to form a prototype spatial light modulator for high frame rate single-pixel imaging,suggesting orders of magnitude improvement over conventional liquid crystal or micromirror-based spatial light modulators.This work opens up the possibility of exploring wavefront engineering for infrared technologies for which fast temporal and spatial modulations are indispensable.
基金support provided through the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningalso partially supported by the National Natural Science Foundation of China(91438108 and 61505062)the Chinese Scholarship Council for supporting their study at the University of Dayton through the Joint Training PhD Program and Visiting Scholar Program
文摘Driven by their potential applications, vectorial optical fields with spatially inhomogeneous states of polarization within the cross section have drawn significant attention recently. This work intends to review some of the latest development of this rapidly growing field of optics and offer a general overview of the current status of this field in a few areas. Mathematical descriptions of generalized vectorial optical fields are provided along with several special examples. A time-reversal methodology for the creation of a wide variety of exotic optical focal fields with prescribed characteristics within the focal volume is presented. Recently developed methods for the generation of vectorial optical fields that utilize fiber lasers,digital lasers, vectorial optical field generator, metasurfaces or photoalignment liquid crystals are summarized. The interactions of these vectorial optical fields with various micro-and nano-structures are presented and the prospects of their potential applications are discussed. The connection of vectorial optical fields with higher dimensionality in quantum information is summarized.
文摘Approximately 80% of breast cancers(BC) are estrogen receptor(ER)-positive and thus endocrine therapy(ET) should be considered complementary to surgery in the majority of patients. The advantages of oophorectomy, adrenalectomy and hypophysectomy in women with advanced BC have been demonstrated many years ago, and currently ET consist of(1) ovarian function suppression(OFS), usually obtained using gonadotropinreleasing hormone agonists(Gn RHa);(2) selective estrogen receptor modulators or down-regulators(SERMs or SERDs); and(3) aromatase inhibitors(AIs), or a combination of two or more drugs. For patients aged less than 50 years and ER+ BC, there is no conclusive evidence that the combination of OFS and SERMs(i.e., tamoxifen) or chemotherapy is superior to OFS alone. Tamoxifen users exhibit a reduced risk of BC, both invasive and in situ, especially during the first 5 years of therapy, and extending the treatment to 10 years further reduced the risk of recurrences. SERDs(i.e., fulvestrant) are especially useful in the neoadjuvant treatment of advanced BC, alone or in combination with either cytotoxic agents or AIs. There are two types of AIs: type Ⅰ are permanent steroidal inhibitors of aromatase, while type Ⅱ are reversible nonsteroidal inhibitors. Several studies demonstrated the superiority of the third-generation AIs(i.e., anastrozole and letrozole) compared with tamoxifen, and adjuvant therapy with AIs reduces the recurrence risk especially in patients with advanced BC. Unfortunately, some cancers are or became ET-resistant, and thus other drugs have been suggested in combination with SERMs or AIs, including cyclin-dependent kinase 4/6 inhibitors(palbociclib) and mammalian target of rapamycin(m TOR) inhibitors, such as everolimus. Further studies are required to confirm their real usefulness.
文摘CD44 is highly expressed in human acute myeloid leukemia （AML） cells. Some experiments had shown that it was possible to reverse differentiation blockage in AML cells by CD44 ligation with specific antibodies, indicating that CD44 was closely related to the differentiation of leukemia cells. The differentiation of acute promyelocytic leukemia cell line HL-60 cells could be induced by all trans-retinoic acid （ATRA） and hexamethylene bisacetamide （HMBA）, but so far the mechanism was not demonstrated clearly. In the present study, we investigated whether ATRA or HMBA induced the growth arrest of HL-60 cells by down-regulating the expression of CD44. The results indicated that the proliferation of HL-60 cells was obviously inhibited and the differentiation was induced by both ATRA and HMBA. The decreased expression of CD44 and cyclin E mRNA, and the increased expression of p27 and p21 at mRNA levels were observed. Furthermore, there was a negative correlation between the expression of CD44 and p27. It was concluded that ATRA and HMBA played a role in the differentiation induction of HL-60 cells, which was mediated by the down-regulation of CD44, accompanied by down-regulation of cyclin E, and up-regulation of p27 and p21 mRNA. Cellular ＆ Molecular Immunology. 2007;4（1）：59-63.
基金the funding support of this research from the National Natural Science Foundation of China(61975143,62027820,62175098)Guangdong Basicand Applied Basic Research Foundation(2021B1515020097).
文摘Active metasurfaces are emerging as the core of next-generation optical devices with their tunable optical responses and flat-compact topography.Especially for the terahertz band,active metasurfaces have been developed as fascinating devices for optical chopping and compressive sensing imaging.However,performance regulation by changing the dielectric parameters of the integrated functional materials exhibits severe limitations and parasitic losses.Here,we introduce a C-shape-split-ring-based phase discontinuity metasurface with liquid crystal elastomer as the substrate for infrared modulation of terahertz wavefront.Line-focused infrared light is applied to manipulate the deflection of the liquid crystal elastomer substrate,enabling controllable and broadband wavefront steering with a maximum output angle change of 22°at 0.68THz.Heating as another control method is also investigated and compared with infrared control.We further demonstrate the performance of liquid crystal elastomer metasurface as a beam steerer,frequency modulator,and tunable beam splitter,which are highly desired in terahertz wireless communication and imaging systems.The proposed scheme demonstrates the promising prospects of mechanically deformable metasurfaces,thereby paving the path for the development of reconfigurable metasurfaces.
