This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to ...This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to bypass corresponding conversion steps when the input falls in a window indicated by a time-domain comparator,which can provide not only the polarity of the input,but also the amount information of the input.The timedomain comparator,which is based on the edge pursing principle,consists of delay cells,two NAND gates,two D-flip-flop register-based phase detectors and a counter.The digital characteristic of the comparator makes the design more flexible,and the comparator can achieve noise and power optimization automatically by simply adjusting the delay cell number.An energy efficient digital-to-analog converter(DAC)control scheme suitable for the skipping window technique is also developed to reduce the switching energy during SAR conversion.Together with the skipping-window technique,the linearity and the power consumption of the SAR ADC are improved.The impact of different window sizes on comparison cycles,DAC switching energy and the overall energy efficiency is analyzed.Simulation results show that the proposed skipping-window technique can improve the overall energy-efficiency of the SAR ADC,as well as the linearity,and the optimized window size for the overall energy efficiency will vary with the DAC switching energy.展开更多
The effects of stage numbers on power dissipation of pipeline analog-to-digital converter (ADC) are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator ...The effects of stage numbers on power dissipation of pipeline analog-to-digital converter (ADC) are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator number algorithm (MCNA) is first introduced, and then the optimum distribution of resolutions through pipeline ADC stages is deduced by MCNA. Based on the optimum stage-resolution distribution, an optimization method is established, which examines the precise function between ADC power and stage resolutions with a parameter of power ratio (Rp). For 10-bit pipeline ADC with scaling down technology, the simulation results by using MATLAB CAD tools show that an eight-stage topology with 1-bit RSD correction achieves the power optimization indicated by the power reduction ratio.展开更多
The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 co...The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 comparator contains a controlled positive feedbackamplifier.Therefore,it is capable of realizing high speed and high precision.For improving theperformance and producibility,the tolerance extension,design centering and potential adaptingtechniques are used in the design of comparator ZJ03.展开更多
To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology developers.The scaling scenario is not an op...To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology developers.The scaling scenario is not an option nowadays and other technologies need to be investigated.The quantum-dot cellular automata(QCA)technology is one of the important emerging nanotechnologies that have attracted much researchers’attention in recent years.This technology has many interesting features,such as high speed,low power consumption,and small size.These features make it an appropriate alternative to the CMOS technique.This paper suggests three novel structures of XNOR gates in the QCA technology.The presented structures do not follow the conventional approaches to the logic gates design but depend on the inherent capabilities of the new technology.The proposed structures are used as the main building blocks for a single-bit comparator.The resulted circuits are simulated for the verification purpose and then compared with existing counterparts in the literature.The comparison results are encouraging to append the proposed structures to the library of QCA gates.展开更多
This paper presents a two-dimension time-domain comparator suitable for low power successive-approximation register(SAR)analog-to-digital converters(ADCs).The proposed two-dimension time-domain comparator consists of ...This paper presents a two-dimension time-domain comparator suitable for low power successive-approximation register(SAR)analog-to-digital converters(ADCs).The proposed two-dimension time-domain comparator consists of a ring oscillator collapse-based comparator and a counter.The propagation delay of a voltage controlled ring oscillator depends on the input.Thus,the comparator can automatically change the comparison time according to its input difference,which can adjust the power consumption of the comparator dynamically without any control logic.And a counter is utilized to count the cycle needed to finish a comparison when the input difference is small.Thus,the proposed comparator can not only provide the polarity of the input,but also the amount information of the input,which helps to skip most of the SAR cycles when the initial input is small.Thus,most energy can be saved when the initial input is small.The proposed time-domain comparator is designed in 0.18μm CMOS technology.Simulation results demonstrate that the comparator can not only save power consumption,but also give the design flexibility,and the current is only nA level when the supply voltage is 0.6 V.展开更多
In recent studies, reversible logic has emerged as a great scene of research, having applications in low power CMOS circuits, optical computing, quantum computing and nanotechnology. The classical logic gates such as ...In recent studies, reversible logic has emerged as a great scene of research, having applications in low power CMOS circuits, optical computing, quantum computing and nanotechnology. The classical logic gates such as AND, OR, EXOR and EXNOR are not reversible. In the existing literature, reversible sequential circuits designs are offered that are improved for the number of the garbage outputs and reversible gates. Minimizing the number of garbage is very noticeable. In the present paper, we show a design of the reversible comparator based on the quantum gates implementation of the reversible DG gate. The reversible DG gate is designed by using 3 × 3 quantum gates such as NOT, CNOT, Controlled-V and Controlled-V+ gates. Also, we have used the TR gate and various types of quantum gates in the implementation results. Low power three-bit comparator is designed using DG Gate, New Gate and Fredkin Gate. In order to evaluate the benefit of using the DG gate proposed in this paper, one-bit comparator is constructed. The design is useful for the future computing techniques like quantum computers. The proposed designs are implemented using VHDL and functionally investigated using Quartus II simulator.展开更多
A low-voltage, high-speed flash ADC is designed. The bottleneck of the operation speed in the low-voltage region is the delay time increase of the comparator. The temporarily boosted comparator is proposed to address ...A low-voltage, high-speed flash ADC is designed. The bottleneck of the operation speed in the low-voltage region is the delay time increase of the comparator. The temporarily boosted comparator is proposed to address this problem. The proposed circuit only boosts the supply voltage in the comparison phase, and therefore, can reduce the delay time while keeping the power overhead to a minimum. Moreover, the body bias control calibration is combined with the temporarily boosted technique. This helps to create a low-power and high-precision comparator. A 0.5-V, 6-bit flash ADC was designed by using 65-nm CMOS technology to demonstrate the effectiveness of the proposed technique. The simulation results showed a high sampling frequency of 1.2 GHz, a low power consumption of 1.4 mW, and an FOM of 28 fJ/conv.-step even at a low supply voltage of 0.5 V.展开更多
There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiven...There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiveness is proved by the actual results which are compared with the magnetic- circuit method and the finite element method. In addition, the reference comment is given which can be used in the practical work of DC current comparator shield design.展开更多
An ultra-high-speed, master-slave voltage comparator circuit is designed and fabricated using InP/GaInAs double heterojunction bipolar transistor technology with a current gain cutoff frequency of 170 GHz. The complet...An ultra-high-speed, master-slave voltage comparator circuit is designed and fabricated using InP/GaInAs double heterojunction bipolar transistor technology with a current gain cutoff frequency of 170 GHz. The complete chip die, including bondpads, is 0.75 × 1.04 mm22. It consumes 440 mW from a single M V power supply, excluding the clock part. 77 DHBTs have been used in the monolithic comparator. A full Nyquist test has been performed up to 20 GHz, with the input sensitivity varying from 6 mV at l0 GHz to 16 mV at 20 GHz. To our knowledge, this is the first InP based integrated circuit including more than 70 DHBTs, and it achieves the highest sampling rate found on the mainland of China.展开更多
The accuracy of A/D and D/A converters depend largely upon their inner comparators. To guarantee 12-bit high resolution for an A/D converter, a precise CMOS comparator consisting of a three-stage differential preampli...The accuracy of A/D and D/A converters depend largely upon their inner comparators. To guarantee 12-bit high resolution for an A/D converter, a precise CMOS comparator consisting of a three-stage differential preamplifier together with a positive feedback latch is proposed. Circuit structure, gain, the principle of input offset voltage storage and latching time constant for the comparator will be analyzed and optimized in this article. With 0.5μm HYNIX mixed signal technology, the simulation result shows that the circuit has a precision of 400 μV at 20 MHz. The test result shows that the circuit has a precision of 600μV at 16 MHz, and dissipates only 78μW of power dissipation at 5 V. The size of the chip is 210 × 180μm^2. The comparator has been successfully used in a 10 MSPS 12-bit A/D converter. The circuit can be also used in a less than 13-bit A/D converter.展开更多
Understanding gene expression variations between species is pivotal for deciphering the evolutionary diversity in phenotypes. Rhesus macaques(Macaca mulatta, MMU)and crab-eating macaques(M. fascicularis, MFA) serve as...Understanding gene expression variations between species is pivotal for deciphering the evolutionary diversity in phenotypes. Rhesus macaques(Macaca mulatta, MMU)and crab-eating macaques(M. fascicularis, MFA) serve as crucial nonhuman primate biomedical models with different phenotypes. To date, however, large-scale comparative transcriptome research between these two species has not yet been fully explored. Here, we conducted systematic comparisons utilizing newly sequenced RNA-seq data from84 samples(41 MFA samples and 43 MMU samples)encompassing 14 common tissues. Our findings revealed a small fraction of genes(3.7%) with differential expression between the two species, as well as 36.5% of genes with tissue-specific expression in both macaques. Comparison of gene expression between macaques and humans indicated that 22.6% of orthologous genes displayed differential expression in at least two tissues. Moreover,19.41% of genes that overlapped with macaque-specific structural variants showed differential expression between humans and macaques. Of these, the FAM220A gene exhibited elevated expression in humans compared to macaques due to lineage-specific duplication. In summary,this study presents a large-scale transcriptomic comparison between MMU and MFA and between macaques and humans. The discovery of gene expression variations not only enhances the biomedical utility of macaque models but also contributes to the wider field of primate genomics.展开更多
A low power 12-bit 200-kS/s SAR ADC is proposed.This features a differential time domain comparator whose offset is cancelled by using a charge pump and a phase frequency detector instead of the preamplifiers usually ...A low power 12-bit 200-kS/s SAR ADC is proposed.This features a differential time domain comparator whose offset is cancelled by using a charge pump and a phase frequency detector instead of the preamplifiers usually needed in a high resolution comparator.The proposed ADC is manufactured in 0.18-μm CMOS technology and the measured SNR and SNDR are 62.5 dB and 59.3 dB,respectively,with a power consumption of 72μW at a 200-kS/s sampling rate.The device operates with a 1.8-V power supply and achieves a FOM of 477 fJ/conversion-step.展开更多
A novel low-offset dynamic comparator for high-speed low-voltage analog-to-digital converters (ADCs) has been proposed.In the proposed comparator,a CMOS switch takes the place of the dynamic current sources in the d...A novel low-offset dynamic comparator for high-speed low-voltage analog-to-digital converters (ADCs) has been proposed.In the proposed comparator,a CMOS switch takes the place of the dynamic current sources in the differential comparator,which allows the differential input transistors still to operate in the saturation region at the comparing time.This gives the proposed comparator a low offset as the differential comparator while tolerating a sub-1-V supply voltage.Additionally,it also features a larger input swing,less sensitivity to common mode voltage,and a simple relationship between the input and reference voltage.This proposed comparator with two traditional comparators has been realized by SMIC 0.13μm CMOS technology.The contrast experimental results verify these advantages over conventional comparators.It has been used in a 12-bit 100-MS/s pipeline ADC.展开更多
This paper presents a differential successive approximation register analog-to-digital converter(SAR ADC) with a novel time-domain comparator design for wireless sensor networks.The prototype chip has been implement...This paper presents a differential successive approximation register analog-to-digital converter(SAR ADC) with a novel time-domain comparator design for wireless sensor networks.The prototype chip has been implemented in the UMC 0.18-μm 1P6M CMOS process.The proposed ADC achieves a peak ENOB of 7.98 at an input frequency of 39.7 kHz and sampling rate of 180 kHz.With the Nyquist input frequency,68.49-dB SFDR,7.97-ENOB is achieved.A simple quadrate layout is adopted to ease the routing complexity of the common-centroid symmetry layout.The ADC maintains a maximum differential nonlinearity of less than 0.08 LSB and integral nonlinearity less than 0.34 LSB by this type of layout.展开更多
The demand of present technology inviting the popularity of multivalued optical computation system to coup up with the latest scenario of ultrahigh processing speed and handling large amount of data The magnitude comp...The demand of present technology inviting the popularity of multivalued optical computation system to coup up with the latest scenario of ultrahigh processing speed and handling large amount of data The magnitude comparator is the heart of the arithmetic and logic unit(ALU)in any logical processing and computing system.In this paper,a trinary magnitude comparator circuit has been proposed and implemented with modified trinary number(MTN)system.Optical tree architecture(OTA)of the proposed circuit has been realized reasonably using Savart plate and spatial light modulators(SLM).A simulation algorithm has also been developed and implemented to prove the authenticity of the proposed circuit through the simulation.展开更多
Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultiv...Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultivars with enhanced traits.Several wheat genes and gene families have been characterized based on their rice orthologs.Rice–wheat orthology can identify genetic regions that regulate similar traits in both crops.Rice–wheat comparative genomics can identify candidate wheat genes in a genomic region identified by association or QTL mapping,deduce their putative functions and biochemical pathways,and develop molecular markers for marker-assisted breeding.A knowledge of gene homology facilitates the transfer between crops of genes or genomic regions associated with desirable traits by genetic engineering,gene editing,or wide crossing.展开更多
The high intraspecies heterogeneity of Baciillus coagulans leads to significant phenotypic differences among different strains.Thus,6 B.coagulans strains were tested in the present study using an irritable bowel syndr...The high intraspecies heterogeneity of Baciillus coagulans leads to significant phenotypic differences among different strains.Thus,6 B.coagulans strains were tested in the present study using an irritable bowel syndrome(IBS)animal model to determine whether the IBS-alleviating effects of B.coagulans strains are strain-specific.The results of this study showed that the ingestion of B.coagulans GBI-30,6086,and B.coagulans CCFM1041 significantly alleviated IBS symptoms in mice.In contrast,other B.coagulans strains showed no or limited alleviating effects on IBS symptoms.According to our experimental results,the two main common features of these strains were as follows:1)The resistance of vegetative cells to bile salts,and 2)ability to synthesize specific lipids and secondary metabolites.Screening strains based on these two indicators may greatly reduce costs and provide a basis for mining new functional B.coagulans strains.Our results also suggest that administration of B.coagulans could significantly regulate microbiota dysbiosis in animal models.Moreover,the close relationships between the gut microbiota,gut microbiota metabolites,and IBS were further confirmed in this study.展开更多
Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochast...Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases.展开更多
基金This work was supported partly by the National Natural Science Foundation of China under Grant No.61704015the General program of Chongqing Natural Science Foundation(a special program for the fundamental and frontier research)under Grant No.cstc2019jcyj-msxmX0108.
文摘This paper presents an energy efficient successive-approximation register(SAR)analog-to-digital converter(ADC)for low-power applications.To improve the overall energy-efficiency,a skipping-window technique is used to bypass corresponding conversion steps when the input falls in a window indicated by a time-domain comparator,which can provide not only the polarity of the input,but also the amount information of the input.The timedomain comparator,which is based on the edge pursing principle,consists of delay cells,two NAND gates,two D-flip-flop register-based phase detectors and a counter.The digital characteristic of the comparator makes the design more flexible,and the comparator can achieve noise and power optimization automatically by simply adjusting the delay cell number.An energy efficient digital-to-analog converter(DAC)control scheme suitable for the skipping window technique is also developed to reduce the switching energy during SAR conversion.Together with the skipping-window technique,the linearity and the power consumption of the SAR ADC are improved.The impact of different window sizes on comparison cycles,DAC switching energy and the overall energy efficiency is analyzed.Simulation results show that the proposed skipping-window technique can improve the overall energy-efficiency of the SAR ADC,as well as the linearity,and the optimized window size for the overall energy efficiency will vary with the DAC switching energy.
基金Supported by the National Natural Science Foundation of China (No. 60072004)
文摘The effects of stage numbers on power dissipation of pipeline analog-to-digital converter (ADC) are studied and a novel design method aiming for power optimization is presented. In this method, a minimum comparator number algorithm (MCNA) is first introduced, and then the optimum distribution of resolutions through pipeline ADC stages is deduced by MCNA. Based on the optimum stage-resolution distribution, an optimization method is established, which examines the precise function between ADC power and stage resolutions with a parameter of power ratio (Rp). For 10-bit pipeline ADC with scaling down technology, the simulation results by using MATLAB CAD tools show that an eight-stage topology with 1-bit RSD correction achieves the power optimization indicated by the power reduction ratio.
文摘The design of a new type of latching voltage comparator ZJ03 is described.Thecommon voltage comparators consist of multistage DC amplifiers,for which it is difficult to realizehigh speed and high precision.The ZJ03 comparator contains a controlled positive feedbackamplifier.Therefore,it is capable of realizing high speed and high precision.For improving theperformance and producibility,the tolerance extension,design centering and potential adaptingtechniques are used in the design of comparator ZJ03.
文摘To fill the continuous needs for faster processing elements with less power consumption causes large pressure on the complementary metal oxide semiconductor(CMOS)technology developers.The scaling scenario is not an option nowadays and other technologies need to be investigated.The quantum-dot cellular automata(QCA)technology is one of the important emerging nanotechnologies that have attracted much researchers’attention in recent years.This technology has many interesting features,such as high speed,low power consumption,and small size.These features make it an appropriate alternative to the CMOS technique.This paper suggests three novel structures of XNOR gates in the QCA technology.The presented structures do not follow the conventional approaches to the logic gates design but depend on the inherent capabilities of the new technology.The proposed structures are used as the main building blocks for a single-bit comparator.The resulted circuits are simulated for the verification purpose and then compared with existing counterparts in the literature.The comparison results are encouraging to append the proposed structures to the library of QCA gates.
基金This work was supported partly by the National Natural Science Foundation of China under grant No.61704015the General program of Chongqing Natural Science Foundation(a special program for the fundamental and frontier research)under grant No.cstc2019jcyj-msxmX0108.
文摘This paper presents a two-dimension time-domain comparator suitable for low power successive-approximation register(SAR)analog-to-digital converters(ADCs).The proposed two-dimension time-domain comparator consists of a ring oscillator collapse-based comparator and a counter.The propagation delay of a voltage controlled ring oscillator depends on the input.Thus,the comparator can automatically change the comparison time according to its input difference,which can adjust the power consumption of the comparator dynamically without any control logic.And a counter is utilized to count the cycle needed to finish a comparison when the input difference is small.Thus,the proposed comparator can not only provide the polarity of the input,but also the amount information of the input,which helps to skip most of the SAR cycles when the initial input is small.Thus,most energy can be saved when the initial input is small.The proposed time-domain comparator is designed in 0.18μm CMOS technology.Simulation results demonstrate that the comparator can not only save power consumption,but also give the design flexibility,and the current is only nA level when the supply voltage is 0.6 V.
文摘In recent studies, reversible logic has emerged as a great scene of research, having applications in low power CMOS circuits, optical computing, quantum computing and nanotechnology. The classical logic gates such as AND, OR, EXOR and EXNOR are not reversible. In the existing literature, reversible sequential circuits designs are offered that are improved for the number of the garbage outputs and reversible gates. Minimizing the number of garbage is very noticeable. In the present paper, we show a design of the reversible comparator based on the quantum gates implementation of the reversible DG gate. The reversible DG gate is designed by using 3 × 3 quantum gates such as NOT, CNOT, Controlled-V and Controlled-V+ gates. Also, we have used the TR gate and various types of quantum gates in the implementation results. Low power three-bit comparator is designed using DG Gate, New Gate and Fredkin Gate. In order to evaluate the benefit of using the DG gate proposed in this paper, one-bit comparator is constructed. The design is useful for the future computing techniques like quantum computers. The proposed designs are implemented using VHDL and functionally investigated using Quartus II simulator.
文摘A low-voltage, high-speed flash ADC is designed. The bottleneck of the operation speed in the low-voltage region is the delay time increase of the comparator. The temporarily boosted comparator is proposed to address this problem. The proposed circuit only boosts the supply voltage in the comparison phase, and therefore, can reduce the delay time while keeping the power overhead to a minimum. Moreover, the body bias control calibration is combined with the temporarily boosted technique. This helps to create a low-power and high-precision comparator. A 0.5-V, 6-bit flash ADC was designed by using 65-nm CMOS technology to demonstrate the effectiveness of the proposed technique. The simulation results showed a high sampling frequency of 1.2 GHz, a low power consumption of 1.4 mW, and an FOM of 28 fJ/conv.-step even at a low supply voltage of 0.5 V.
文摘There are magnetic interference problems in the applications of DC current comparator. Analysis on the magnetic effectiveness which is applied by the external magnetic field is introduced in this paper. The effectiveness is proved by the actual results which are compared with the magnetic- circuit method and the finite element method. In addition, the reference comment is given which can be used in the practical work of DC current comparator shield design.
文摘An ultra-high-speed, master-slave voltage comparator circuit is designed and fabricated using InP/GaInAs double heterojunction bipolar transistor technology with a current gain cutoff frequency of 170 GHz. The complete chip die, including bondpads, is 0.75 × 1.04 mm22. It consumes 440 mW from a single M V power supply, excluding the clock part. 77 DHBTs have been used in the monolithic comparator. A full Nyquist test has been performed up to 20 GHz, with the input sensitivity varying from 6 mV at l0 GHz to 16 mV at 20 GHz. To our knowledge, this is the first InP based integrated circuit including more than 70 DHBTs, and it achieves the highest sampling rate found on the mainland of China.
基金supported by the National High Technology Research and Development Program of China(No.2006AA05Z211).
文摘The accuracy of A/D and D/A converters depend largely upon their inner comparators. To guarantee 12-bit high resolution for an A/D converter, a precise CMOS comparator consisting of a three-stage differential preamplifier together with a positive feedback latch is proposed. Circuit structure, gain, the principle of input offset voltage storage and latching time constant for the comparator will be analyzed and optimized in this article. With 0.5μm HYNIX mixed signal technology, the simulation result shows that the circuit has a precision of 400 μV at 20 MHz. The test result shows that the circuit has a precision of 600μV at 16 MHz, and dissipates only 78μW of power dissipation at 5 V. The size of the chip is 210 × 180μm^2. The comparator has been successfully used in a 10 MSPS 12-bit A/D converter. The circuit can be also used in a less than 13-bit A/D converter.
基金supported by the National Natural Science Foundation of China (82021001 and 31825018 to Q.S., 32370658 to Y.M.,82001372 to X.Y.)National Key Research and Development Program of China (2022YFF0710901)+2 种基金National Science and Technology Innovation2030 Major Program (2021ZD0200900) to Q.S.Shanghai Pujiang Program (22PJ1407300)Shanghai Jiao Tong University 2030 Initiative (WH510363001-7) to Y.M。
文摘Understanding gene expression variations between species is pivotal for deciphering the evolutionary diversity in phenotypes. Rhesus macaques(Macaca mulatta, MMU)and crab-eating macaques(M. fascicularis, MFA) serve as crucial nonhuman primate biomedical models with different phenotypes. To date, however, large-scale comparative transcriptome research between these two species has not yet been fully explored. Here, we conducted systematic comparisons utilizing newly sequenced RNA-seq data from84 samples(41 MFA samples and 43 MMU samples)encompassing 14 common tissues. Our findings revealed a small fraction of genes(3.7%) with differential expression between the two species, as well as 36.5% of genes with tissue-specific expression in both macaques. Comparison of gene expression between macaques and humans indicated that 22.6% of orthologous genes displayed differential expression in at least two tissues. Moreover,19.41% of genes that overlapped with macaque-specific structural variants showed differential expression between humans and macaques. Of these, the FAM220A gene exhibited elevated expression in humans compared to macaques due to lineage-specific duplication. In summary,this study presents a large-scale transcriptomic comparison between MMU and MFA and between macaques and humans. The discovery of gene expression variations not only enhances the biomedical utility of macaque models but also contributes to the wider field of primate genomics.
基金Project supported by the National Natural Science Foundation of China(No.60876021)the State Key Laboratory Project,China (No.MS20080203)
文摘A low power 12-bit 200-kS/s SAR ADC is proposed.This features a differential time domain comparator whose offset is cancelled by using a charge pump and a phase frequency detector instead of the preamplifiers usually needed in a high resolution comparator.The proposed ADC is manufactured in 0.18-μm CMOS technology and the measured SNR and SNDR are 62.5 dB and 59.3 dB,respectively,with a power consumption of 72μW at a 200-kS/s sampling rate.The device operates with a 1.8-V power supply and achieves a FOM of 477 fJ/conversion-step.
基金Project supported by the National High Technology Research and Development Program of China(No.2009AA011600)the Young Scientists Fund of Fudan University,China(No.09FQ33)the State Key Laboratory of ASIC and System,Fudan University,China(No. 09MS008)
文摘A novel low-offset dynamic comparator for high-speed low-voltage analog-to-digital converters (ADCs) has been proposed.In the proposed comparator,a CMOS switch takes the place of the dynamic current sources in the differential comparator,which allows the differential input transistors still to operate in the saturation region at the comparing time.This gives the proposed comparator a low offset as the differential comparator while tolerating a sub-1-V supply voltage.Additionally,it also features a larger input swing,less sensitivity to common mode voltage,and a simple relationship between the input and reference voltage.This proposed comparator with two traditional comparators has been realized by SMIC 0.13μm CMOS technology.The contrast experimental results verify these advantages over conventional comparators.It has been used in a 12-bit 100-MS/s pipeline ADC.
基金supported by the National Natural Science Foundation of China(No.60976032)
文摘This paper presents a differential successive approximation register analog-to-digital converter(SAR ADC) with a novel time-domain comparator design for wireless sensor networks.The prototype chip has been implemented in the UMC 0.18-μm 1P6M CMOS process.The proposed ADC achieves a peak ENOB of 7.98 at an input frequency of 39.7 kHz and sampling rate of 180 kHz.With the Nyquist input frequency,68.49-dB SFDR,7.97-ENOB is achieved.A simple quadrate layout is adopted to ease the routing complexity of the common-centroid symmetry layout.The ADC maintains a maximum differential nonlinearity of less than 0.08 LSB and integral nonlinearity less than 0.34 LSB by this type of layout.
文摘The demand of present technology inviting the popularity of multivalued optical computation system to coup up with the latest scenario of ultrahigh processing speed and handling large amount of data The magnitude comparator is the heart of the arithmetic and logic unit(ALU)in any logical processing and computing system.In this paper,a trinary magnitude comparator circuit has been proposed and implemented with modified trinary number(MTN)system.Optical tree architecture(OTA)of the proposed circuit has been realized reasonably using Savart plate and spatial light modulators(SLM).A simulation algorithm has also been developed and implemented to prove the authenticity of the proposed circuit through the simulation.
文摘Rice and wheat provide nearly 40%of human calorie and protein requirements.They share a common ancestor and belong to the Poaceae(grass)family.Characterizing their genetic homology is crucial for developing new cultivars with enhanced traits.Several wheat genes and gene families have been characterized based on their rice orthologs.Rice–wheat orthology can identify genetic regions that regulate similar traits in both crops.Rice–wheat comparative genomics can identify candidate wheat genes in a genomic region identified by association or QTL mapping,deduce their putative functions and biochemical pathways,and develop molecular markers for marker-assisted breeding.A knowledge of gene homology facilitates the transfer between crops of genes or genomic regions associated with desirable traits by genetic engineering,gene editing,or wide crossing.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20200084)the National Natural Science Foundation of China(31871773 and 31820103010)+1 种基金the Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province and Key Talents Project of“Strengthening Health through Science and Education”of Wuxi Health and Family Planning Commission(ZDRC039)Top Talents Project of“Six-one Project”for High-level Health Talents in Jiangsu Province(LGY2018016)。
文摘The high intraspecies heterogeneity of Baciillus coagulans leads to significant phenotypic differences among different strains.Thus,6 B.coagulans strains were tested in the present study using an irritable bowel syndrome(IBS)animal model to determine whether the IBS-alleviating effects of B.coagulans strains are strain-specific.The results of this study showed that the ingestion of B.coagulans GBI-30,6086,and B.coagulans CCFM1041 significantly alleviated IBS symptoms in mice.In contrast,other B.coagulans strains showed no or limited alleviating effects on IBS symptoms.According to our experimental results,the two main common features of these strains were as follows:1)The resistance of vegetative cells to bile salts,and 2)ability to synthesize specific lipids and secondary metabolites.Screening strains based on these two indicators may greatly reduce costs and provide a basis for mining new functional B.coagulans strains.Our results also suggest that administration of B.coagulans could significantly regulate microbiota dysbiosis in animal models.Moreover,the close relationships between the gut microbiota,gut microbiota metabolites,and IBS were further confirmed in this study.
基金supported by the National Natural Science Foundation of China(Grant Nos.82173620 to Yang Zhao and 82041024 to Feng Chen)partially supported by the Bill&Melinda Gates Foundation(Grant No.INV-006371 to Feng Chen)Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Deterministic compartment models(CMs)and stochastic models,including stochastic CMs and agent-based models,are widely utilized in epidemic modeling.However,the relationship between CMs and their corresponding stochastic models is not well understood.The present study aimed to address this gap by conducting a comparative study using the susceptible,exposed,infectious,and recovered(SEIR)model and its extended CMs from the coronavirus disease 2019 modeling literature.We demonstrated the equivalence of the numerical solution of CMs using the Euler scheme and their stochastic counterparts through theoretical analysis and simulations.Based on this equivalence,we proposed an efficient model calibration method that could replicate the exact solution of CMs in the corresponding stochastic models through parameter adjustment.The advancement in calibration techniques enhanced the accuracy of stochastic modeling in capturing the dynamics of epidemics.However,it should be noted that discrete-time stochastic models cannot perfectly reproduce the exact solution of continuous-time CMs.Additionally,we proposed a new stochastic compartment and agent mixed model as an alternative to agent-based models for large-scale population simulations with a limited number of agents.This model offered a balance between computational efficiency and accuracy.The results of this research contributed to the comparison and unification of deterministic CMs and stochastic models in epidemic modeling.Furthermore,the results had implications for the development of hybrid models that integrated the strengths of both frameworks.Overall,the present study has provided valuable epidemic modeling techniques and their practical applications for understanding and controlling the spread of infectious diseases.