Breeding semi-dwarf varieties to improve lodging resistance has been proven to be enormously successful in increasing grain yield since the advent of the "green revolution." However, the breeding of the majority of ...Breeding semi-dwarf varieties to improve lodging resistance has been proven to be enormously successful in increasing grain yield since the advent of the "green revolution." However, the breeding of the majority of semi-dwarf rice varieties in Asia has been dependent mainly on genetic introduction of the mutant alleles of SD1, which encodes a gibberellin (GA) 20-oxidase, OsGA20ox2, for catalyzing GA biosynthesis. Here, we report a new rice lodging-resistance gene, Shortened Basal lnternodes (SBI), which encodes a gibberellin 2- oxidase and specifically controls the elongation of culm basal internodes through deactivating GA activity. SBI is predominantly expressed in culm basal internodes. Genetic analyses indicate that SBI is a semidominant gene affecting rice height and lodging resistance. SBI allelic variants display different activities and are associated with the height of rice varieties. Breeding with higher activity of the SBI allele generates new rice varieties with improved lodging resistance and increased yield. The discovery of the SB! provides a desirable gene resource for producing semi-dwarf rice phenotypes and offers an effective strategy for breeding rice varieties with enhanced lodging resistance and high yield.展开更多
Dear Editor,CRISPR(clustered regularly interspaced short palindromic repeats)/Cas genome editing is a powerful tool for introducing specific mutations in organisms including plants.The system is composed of a nuclease...Dear Editor,CRISPR(clustered regularly interspaced short palindromic repeats)/Cas genome editing is a powerful tool for introducing specific mutations in organisms including plants.The system is composed of a nuclease such as Cas9 or Cas12a and an engineered single-guide RNA(sgRNA)incorporating a target sequence(Li et al.,2019).A Cas9/sgRNA complex recognizes its target site in the genome,resulting in a mutation at that site.展开更多
In this paper,we propose the two-stage constructions for the rate-compatible shortened polar(RCSP)codes.For the Stage-I construction,the shortening pattern and the frozen bit are jointly designed to make the shortened...In this paper,we propose the two-stage constructions for the rate-compatible shortened polar(RCSP)codes.For the Stage-I construction,the shortening pattern and the frozen bit are jointly designed to make the shortened bits be completely known by the decoder.Besides,a distance-greedy algorithm is presented to improve the minimum Hamming distance of the codes.To design the remaining Stage-II frozen bits,three different construction algorithms are further presented,called the Reed-Muller(RM)construction,the Gaussian Approximation(GA)construction,and the RM-GA construction.Then we give the row weight distribution numerical results of the generator matrix after the Stage-I and Stage-II constructions,which shows that the proposed constructions can efficiently increase the minimum Hamming distance.Simulation results show that the proposed RCSP codes have excellent frame error rate(FER)performances at different code lengths and code rates.More specifically,the RM-GA construction performs best and can achieve at most 0.8 dB gain compared to the Wang14 and the quasi-uniform puncturing(QUP)schemes.The RM construction is designed completely by the distance-constraint without channel evaluation thus has the simplest structure.Interestingly,it still has better FER performance than the existing shortening/puncturing schemes,especially at high signal noise ratio(SNR)region.展开更多
Due to its excellent biocompatibility and biodegradability,Mg and its alloys are considered to be promising materials for manufacturing of vascular sent.However,the manufacture of high-precision and high-performance M...Due to its excellent biocompatibility and biodegradability,Mg and its alloys are considered to be promising materials for manufacturing of vascular sent.However,the manufacture of high-precision and high-performance Mg alloys minitubes is still a worldwide problem with a long manufacturing processing caused by the poor workability of Mg alloys.To solve this problem,the cyclic extrusion compression(CEC)was used to pretreat the billet by improving the workability of Mg alloys,finally shortening the manufacturing process.After CEC treatment,the size of grains and second phase particles of Mg alloys were dramatically refined to 3.2μm and 0.3μm,respectively.Only after three passes of cold drawing,the wall thickness of minitube was reduced from 0.200 mm to 0.135 mm and a length was more than 1000 mm.The error of wall thickness was measured to be less than 0.01 mm,implying a high dimensional accuracy.The yield strength(YS),ultimate tensile strength(UTS)and elongation of finished minitube were 220±10 MPa,290±10 MPa and 22.0±0.5%,respectively.In addition,annealing can improve mechanical property and corrosion resistance of minitubes by improving the homogeneity of the microstructure and enhancing the density of basal texture.展开更多
Fluid shortening is an important ingredient in the production of sponge cake. Peanut oil with 0, 43% and 85% of diacylglycerol content was used as the base oil. Different emulsifiers, such as glycerol monostearate, so...Fluid shortening is an important ingredient in the production of sponge cake. Peanut oil with 0, 43% and 85% of diacylglycerol content was used as the base oil. Different emulsifiers, such as glycerol monostearate, soy lecithin and sucrose ester, and their respective amounts, were investigated. It was found that the addition of emulsifiers had a positive effect on water-absorbing capacity, air-absorbing capacity and viscosity of the oils. Glycerol monostearate was the preferred emulsifier for fluid shortening with a recommended addition of 1.5%. The effects of different diacylglycerol content on fluid shortening and their impact on sponge cake production was also investigated. The onset oxidation temperature of the oil could be increased from 253.21 ℃ for PO-TAG-based fluid shortening to 263.70 ℃ for PO-DAG85-based fluid shortening. And the increase in diacylglycerol content leading to a lower specific gravity of the batter, which was 1.06 g/mL, 1.02 g/mL and 0.98 g/mL prepared by PO-DAG, PO-DAG43 and PO-DAG85 shortening, respectively. The results showed that diacylglycerols can be used as base oils in fluid shortening to improve the crystal network and stability of fluid shortenings, thereby reducing the specific gravity of the batter and improving the structural properties of the cake. This will extend the potential applications of diacylglycerols and increase the variety of base oils available for fluid shortening preparation.展开更多
The demand for high-data-rate underwater acoustic communications(UACs)in marine development is increasing;however,severe multipaths make demodulation a challenge.The decision feedback equalizer(DFE)is one of the most ...The demand for high-data-rate underwater acoustic communications(UACs)in marine development is increasing;however,severe multipaths make demodulation a challenge.The decision feedback equalizer(DFE)is one of the most popular equalizers in UAC;however,it is not the optimal algorithm.Although maximum likelihood sequence estimation(MLSE)is the optimal algorithm,its complexity increases exponentially with the number of channel taps,making it challenging to apply to UAC.Therefore,this paper proposes a complexity-reduced MLSE to improve the bit error rate(BER)performance in multipath channels.In the proposed algorithm,the original channel is first shortened using a channel-shortening method,and several dominant channel taps are selected for MLSE.Subsequently,sphere decoding(SD)is performed in the following MLSE.Iterations are applied to eliminate inter-symbol interference caused by weak channel taps.The simulation and sea experiment demonstrate the superiority of the proposed algorithm.The simulation results show that channel shortening combined with SD can drastically reduce computational complexity,and iterative SD performs better than DFE based on recursive least squares(RLS-DFE),DFE based on improved proportionate normalized least mean squares(IPNLMS-DFE),and channel estimation-based DFE(CE-DFE).Moreover,the sea experimental results at Zhairuoshan Island in Zhoushan show that the proposed receiver scheme has improved BER performance over RLSDFE,IPNLMS-DFE,and CE-DFE.Compared with the RLS-DFE,the BER,after five iterations,is reduced from 0.0076 to 0.0037 in the 8–12 k Hz band and from 0.1516 to 0.1145 in the 13–17 k Hz band at a distance of 2000 m.Thus,the proposed algorithm makes it possible to apply MLSE in UAC in practical scenarios.展开更多
With the rapid advancement of computing and information technology at the turn of the 21st century,the power of data collection and processing has multiplied tremendously.Based on this a game-changing advancement,scie...With the rapid advancement of computing and information technology at the turn of the 21st century,the power of data collection and processing has multiplied tremendously.Based on this a game-changing advancement,science is at the advent of the “fourth paradigm”of massive data plus artificial intelligence,in which the efficiency of scientific research is continuously improved,research time is shortened,and research cost is reduced[1].展开更多
Insufficient knowledge of the germination ecology of local species is one of the main constraints to restoration of degraded rural lands. We tested seeds from fourteen Sudanian savanna species targeted for restoration...Insufficient knowledge of the germination ecology of local species is one of the main constraints to restoration of degraded rural lands. We tested seeds from fourteen Sudanian savanna species targeted for restoration for their response to two different pretreatments(conventional and prolonged acid pretreatments) and two different storage conditions(ambient room conditions and refrigerator at 4 C). For 6 of the studied species, longer soaking in sulphuric acid significantly improved germination rates and also reduced the germination time of some species. Storage condition, in general did not affect germination rates except for two species where cool storage depressed germination. The practical implication is that, for the species tested, when mature seeds are collected for plantation in the upcoming rainy season, there is no need to invest in infrastructure and energy for storing in cold conditions.The study also revealed that in general when seeds are stored in ambient conditions from the time of collection up to seeding time, although germination rate does not increase, germination time is shortened and this could be of great interest in synchronizing germination in real field conditions.展开更多
Common abbreviations,acronyms and short names are listed below.These shortened forms,and otherabbreviations not in this list,should always be defined at first usage in both abstract and text.Some of themare well-known...Common abbreviations,acronyms and short names are listed below.These shortened forms,and otherabbreviations not in this list,should always be defined at first usage in both abstract and text.Some of themare well-known and can be used directly without confusion.展开更多
Sciatica is a commonly seen illness withmultifactorial pathogenesis. The symptomsare characterized by pain in the affected legand functional disabilities. Since 1986, theauthor has adopted acupuncture at thelumbar Jia...Sciatica is a commonly seen illness withmultifactorial pathogenesis. The symptomsare characterized by pain in the affected legand functional disabilities. Since 1986, theauthor has adopted acupuncture at thelumbar Jiaji points (Extra 21) for treatmentof the condition with marked efficacy. Thecure rate has been high and the treatmentcourse greatly shortened, as reported in thefollowing.展开更多
In this paper, we observed the effect of moxibustion on the positive reactionin uroprotein test, the time of hypouresis and the change of B-mode echography of kidney of thepatient with EHF. We measured the change of B...In this paper, we observed the effect of moxibustion on the positive reactionin uroprotein test, the time of hypouresis and the change of B-mode echography of kidney of thepatient with EHF. We measured the change of BUN content in serum of the rat infected withEHF virus (EHFV) before and after moxibustion. Results showed moxibustion could shortenthe time of hypouresis, promote the removal of positive reaction in the uroprotein test, decreasethe content of BUN in serum and reduce the swelling of kidney. All these results suggested thatmoxibustion might have the effect on protecting kidney function in some degree.展开更多
There are two kinds of generating equipment in a firmly con-nected power network,one is water power plants(shortenedas“water power”,below),the other is thermal power plants(includingcoal-fired,oil-fired and nuclear ...There are two kinds of generating equipment in a firmly con-nected power network,one is water power plants(shortenedas“water power”,below),the other is thermal power plants(includingcoal-fired,oil-fired and nuclear power plants,but the analysis in thisarticle is based mainly on coal-fired power generation.And they willbe shortened as“thermal power”below).As far as power output isconcerned,when the share of water power installed capacity展开更多
Objective:To investigate the Effects of Metoprolol on QTDispersion(QTd)and Heart Rate Variability(HRV)in Patientswith Coronary Artery Disease(CAD).Methods:The changes of QTd and HRV were investigatedbefore and after a...Objective:To investigate the Effects of Metoprolol on QTDispersion(QTd)and Heart Rate Variability(HRV)in Patientswith Coronary Artery Disease(CAD).Methods:The changes of QTd and HRV were investigatedbefore and after administrating Metoprolol(93.75±22.8mg/d)for two weeks in the 24 patients with CAD.Results:Compared with healthy adults,the QTd,QTcd andQTmax were significantly higher(p【0.05)in the patients withCAD,and the QTmin lengthened and the QTd shortened whentaking Valsalva s respiration,the SDNNindex,rMSSD,PNN50and HF increased significantly(p【0.01),and LF/HF ratiodecreased,but the SDNN,SDANN and LF did not change afteradministrating Metoprolol.In addition,the QTmin shortened,the QTd,QTcd lengthened significantly(p【0.05),but the QTmaxhad no significant change after administratingMetoprolol(p】0.05).Condusions:The results suggest that the sympathetic nervecould regulate the repolarization speed of the normalventricular myocardium,and change the QTd in the patientswith CAD,Metoprolol relieve not only angina pectoris byincreasing efficiently the blood supply,and decreasing theoxygen demand of the myocardium,but also shorten markedlythe QTd.展开更多
Shortening is one of important word formations which demands attentions of both teachers and students. The paper first briefly introduces shortening words in English into clipped words, initialisms, acronyms and blend...Shortening is one of important word formations which demands attentions of both teachers and students. The paper first briefly introduces shortening words in English into clipped words, initialisms, acronyms and blends,and then it mainly explores the reasons why shortening words appear and become popular.展开更多
920024 The TCM-WM treatment of severerenal failure inpatients with epidemichemorrhagic fever.LIU Junbin (刘俊彬),et al.Dept Infect Dis,Xijing Hosp,Xi’an,710032.ChinIntegr Tradit & West Med 1991;11(8):484-485.This...920024 The TCM-WM treatment of severerenal failure inpatients with epidemichemorrhagic fever.LIU Junbin (刘俊彬),et al.Dept Infect Dis,Xijing Hosp,Xi’an,710032.ChinIntegr Tradit & West Med 1991;11(8):484-485.This article reports the treatment of 23 cases(with the control group 20 cases) of severe renalfailure in patients with epidemic hemorrhagicfever (EHF)by integrated traditional Chinesemedicine arid western medicine (TCM-WM),i.e.the renal protective decoction and modernmedical treatment during the period of 1988~1989.The effects were found as follows:(1)展开更多
920690 A clinical study of the relationshipbetween regulation of electrolytes andsubsidence of cirrhotics ascites. HOUShuqin (侯淑琴), et al. Dept Gastroenterol, Nan-fang Hosp, 1st Med Univ, PLA, Guangzhou.Chin J Dige...920690 A clinical study of the relationshipbetween regulation of electrolytes andsubsidence of cirrhotics ascites. HOUShuqin (侯淑琴), et al. Dept Gastroenterol, Nan-fang Hosp, 1st Med Univ, PLA, Guangzhou.Chin J Digest 1992; 12(2): 84-86. Mechanism of many diuretics is based展开更多
Two encouraging results were reportedby the end of 1988.Firstry,a new pro-cess for extraction of RE elements froman ion-adsorption type RE mineral;se-condly,serial production of hi-puritySc has been effective.There ar...Two encouraging results were reportedby the end of 1988.Firstry,a new pro-cess for extraction of RE elements froman ion-adsorption type RE mineral;se-condly,serial production of hi-puritySc has been effective.There are several varieties of ion-adsorption type RE minerals occur inSouth China.They differ in RE contents,展开更多
The Qaidam Basin, located in the northern margin of the Qinghai-Tibet Plateau, is a large Mesozoic-Cenozoic basin, and bears huge thick Cenozoic strata. The geologic events of the Indian- Eurasian plate-plate collisio...The Qaidam Basin, located in the northern margin of the Qinghai-Tibet Plateau, is a large Mesozoic-Cenozoic basin, and bears huge thick Cenozoic strata. The geologic events of the Indian- Eurasian plate-plate collision since -55 Ma have been well recorded. Based on the latest progress in high-resolution stratigraphy, a technique of balanced section was applied to six pieces of northeast- southwest geologic seismic profiles in the central and eastern of the Qaidam Basin to reconstruct the crustal shortening deformation history during the Cenozoic collision. The results show that the Qaidam Basin began to shorten deformation nearly synchronous to the early collision, manifesting as a weak compression, the deformation increased significantly during the Middle and Late Eocene, and then weakened slightly and began to accelerate rapidly since the Late Miocene, especially since the Quaternary, reflecting this powerful compressional deformation and rapid uplift of the northern Tibetan Plateau around the Qaidam Basin.展开更多
The eastern margin of the Qaidam Basin lies in the key tectonic location connecting the Qinling, Qilian and East Kunlun orogens. The paper presents an investigation and analysis of the geologic structures of the area ...The eastern margin of the Qaidam Basin lies in the key tectonic location connecting the Qinling, Qilian and East Kunlun orogens. The paper presents an investigation and analysis of the geologic structures of the area and LA-ICP MS zircon U-Pb dating of Paleozoic and Mesozoic magmatisms of granitoids in the basement of the eastern Qaidam Basin on the basis of 16 granitoid samples collected from the South Qilian Mountains, the Qaidam Basin basement and the East Kunlun Mountains. According to the results in this paper, the basement of the basin, from the northern margin of the Qaidam Basin to the East Kunlun Mountains, has experienced at least three periods of intrusive activities of granitoids since the Early Paleozoic, i.e. the magmatisms occurring in the Late Cambrian (493.1±4.9 Ma), the Silurian (422.9±8.0 Ma-420.4±4.6 Ma) and the Late Permian-Middle Triassic (257.8±4.0 Ma-228.8+1.5 Ma), respectively. Among them, the Late Permian - Middle Triassic granitoids form the main components of the basement of the basin. The statistics of dated zircons in this paper shows the intrusive magmatic activities in the basement of the basin have three peak ages of 244 Ma (main), 418 Ma, and 493 Ma respectively. The dating results reveal that the Early Paleozoic magmatism of granitoids mainly occurred on the northern margin of the Qaidam Basin and the southern margin of the Qilian Mountains, with only weak indications in the East Kunlun Mountains. However, the distribution of Permo-Triassic (P-T) granitoids occupied across the whole basement of the eastern Qaidam Basin from the southern margin of the Qilian Mountains to the East Kunlun Mountains. An integrated analysis of the age distribution of P-T granitoids in the Qaidam Basin and its surrounding mountains shows that the earliest P-T magmatism (293.6-270 Ma) occurred in the northwestern part of the basin and expanded eastwards and southwards, resulting in the P-T intrusive magmatism that ran through the whole basin basement. As the Cenozoic basement thrust system developed in the eastern Qaidam Basin, the nearly N-S-trending shortening and deformation in the basement of the basin tended to intensify from west to east, which went contrary to the distribution trend of N-S-trending shortening and deformation in the Cenozoic cover of the basin, reflecting that there was a transformation of shortening and thickening of Cenozoic crust between the eastern and western parts of the Qaidam Basin, i.e., the crustal shortening of eastern Qaidam was dominated by the basement deformation (triggered at the middle and lower crust), whereas that of western Qaidam was mainly by folding and thrusting of the sedimentary cover (the upper crust).展开更多
基金This work was supported by the Chinese Academy of Sciences (CEMPS2016009 XDA08020203), the Ministry of Science and Technology of China (2013CB127002 2016YFD0102102), and the National Natural Science Foundation of China (31571635).
文摘Breeding semi-dwarf varieties to improve lodging resistance has been proven to be enormously successful in increasing grain yield since the advent of the "green revolution." However, the breeding of the majority of semi-dwarf rice varieties in Asia has been dependent mainly on genetic introduction of the mutant alleles of SD1, which encodes a gibberellin (GA) 20-oxidase, OsGA20ox2, for catalyzing GA biosynthesis. Here, we report a new rice lodging-resistance gene, Shortened Basal lnternodes (SBI), which encodes a gibberellin 2- oxidase and specifically controls the elongation of culm basal internodes through deactivating GA activity. SBI is predominantly expressed in culm basal internodes. Genetic analyses indicate that SBI is a semidominant gene affecting rice height and lodging resistance. SBI allelic variants display different activities and are associated with the height of rice varieties. Breeding with higher activity of the SBI allele generates new rice varieties with improved lodging resistance and increased yield. The discovery of the SB! provides a desirable gene resource for producing semi-dwarf rice phenotypes and offers an effective strategy for breeding rice varieties with enhanced lodging resistance and high yield.
基金grants from the National Natural Science Foundation of China (91435203 and 31991222)the Major Program of Guangdong Basic and Applied Basic Research (2019B030302006)。
文摘Dear Editor,CRISPR(clustered regularly interspaced short palindromic repeats)/Cas genome editing is a powerful tool for introducing specific mutations in organisms including plants.The system is composed of a nuclease such as Cas9 or Cas12a and an engineered single-guide RNA(sgRNA)incorporating a target sequence(Li et al.,2019).A Cas9/sgRNA complex recognizes its target site in the genome,resulting in a mutation at that site.
基金This work was supported by the Interdisciplinary Scientific Research Foundation of GuangXi University(No.2022JCC015)the National Natural Science Foundation of China(Nos.61761006,61961004,and 61762011)the Natural Science Foundation of Guangxi of China(Nos.2017GXNSFAA198263 and 2018GXNSFAA2940。
文摘In this paper,we propose the two-stage constructions for the rate-compatible shortened polar(RCSP)codes.For the Stage-I construction,the shortening pattern and the frozen bit are jointly designed to make the shortened bits be completely known by the decoder.Besides,a distance-greedy algorithm is presented to improve the minimum Hamming distance of the codes.To design the remaining Stage-II frozen bits,three different construction algorithms are further presented,called the Reed-Muller(RM)construction,the Gaussian Approximation(GA)construction,and the RM-GA construction.Then we give the row weight distribution numerical results of the generator matrix after the Stage-I and Stage-II constructions,which shows that the proposed constructions can efficiently increase the minimum Hamming distance.Simulation results show that the proposed RCSP codes have excellent frame error rate(FER)performances at different code lengths and code rates.More specifically,the RM-GA construction performs best and can achieve at most 0.8 dB gain compared to the Wang14 and the quasi-uniform puncturing(QUP)schemes.The RM construction is designed completely by the distance-constraint without channel evaluation thus has the simplest structure.Interestingly,it still has better FER performance than the existing shortening/puncturing schemes,especially at high signal noise ratio(SNR)region.
基金supported by the National Key Research and Development Program of China(2021YFC2400703)the Key Projects of the Joint Fund of the National Natural Science Foundation of China(U1804251).
文摘Due to its excellent biocompatibility and biodegradability,Mg and its alloys are considered to be promising materials for manufacturing of vascular sent.However,the manufacture of high-precision and high-performance Mg alloys minitubes is still a worldwide problem with a long manufacturing processing caused by the poor workability of Mg alloys.To solve this problem,the cyclic extrusion compression(CEC)was used to pretreat the billet by improving the workability of Mg alloys,finally shortening the manufacturing process.After CEC treatment,the size of grains and second phase particles of Mg alloys were dramatically refined to 3.2μm and 0.3μm,respectively.Only after three passes of cold drawing,the wall thickness of minitube was reduced from 0.200 mm to 0.135 mm and a length was more than 1000 mm.The error of wall thickness was measured to be less than 0.01 mm,implying a high dimensional accuracy.The yield strength(YS),ultimate tensile strength(UTS)and elongation of finished minitube were 220±10 MPa,290±10 MPa and 22.0±0.5%,respectively.In addition,annealing can improve mechanical property and corrosion resistance of minitubes by improving the homogeneity of the microstructure and enhancing the density of basal texture.
基金The Bureau of Science and Information of Guangzhou under grant 2024A04J3254the National Natural Science Foundation of China under grant 32272341the Department of Science and Technology of Guangdong Province under grant numbers 2022B0202010003。
文摘Fluid shortening is an important ingredient in the production of sponge cake. Peanut oil with 0, 43% and 85% of diacylglycerol content was used as the base oil. Different emulsifiers, such as glycerol monostearate, soy lecithin and sucrose ester, and their respective amounts, were investigated. It was found that the addition of emulsifiers had a positive effect on water-absorbing capacity, air-absorbing capacity and viscosity of the oils. Glycerol monostearate was the preferred emulsifier for fluid shortening with a recommended addition of 1.5%. The effects of different diacylglycerol content on fluid shortening and their impact on sponge cake production was also investigated. The onset oxidation temperature of the oil could be increased from 253.21 ℃ for PO-TAG-based fluid shortening to 263.70 ℃ for PO-DAG85-based fluid shortening. And the increase in diacylglycerol content leading to a lower specific gravity of the batter, which was 1.06 g/mL, 1.02 g/mL and 0.98 g/mL prepared by PO-DAG, PO-DAG43 and PO-DAG85 shortening, respectively. The results showed that diacylglycerols can be used as base oils in fluid shortening to improve the crystal network and stability of fluid shortenings, thereby reducing the specific gravity of the batter and improving the structural properties of the cake. This will extend the potential applications of diacylglycerols and increase the variety of base oils available for fluid shortening preparation.
基金Supported by the National Natural Science Foundation of China under Grant Nos. 62101489, 62171405 and 62225114.
文摘The demand for high-data-rate underwater acoustic communications(UACs)in marine development is increasing;however,severe multipaths make demodulation a challenge.The decision feedback equalizer(DFE)is one of the most popular equalizers in UAC;however,it is not the optimal algorithm.Although maximum likelihood sequence estimation(MLSE)is the optimal algorithm,its complexity increases exponentially with the number of channel taps,making it challenging to apply to UAC.Therefore,this paper proposes a complexity-reduced MLSE to improve the bit error rate(BER)performance in multipath channels.In the proposed algorithm,the original channel is first shortened using a channel-shortening method,and several dominant channel taps are selected for MLSE.Subsequently,sphere decoding(SD)is performed in the following MLSE.Iterations are applied to eliminate inter-symbol interference caused by weak channel taps.The simulation and sea experiment demonstrate the superiority of the proposed algorithm.The simulation results show that channel shortening combined with SD can drastically reduce computational complexity,and iterative SD performs better than DFE based on recursive least squares(RLS-DFE),DFE based on improved proportionate normalized least mean squares(IPNLMS-DFE),and channel estimation-based DFE(CE-DFE).Moreover,the sea experimental results at Zhairuoshan Island in Zhoushan show that the proposed receiver scheme has improved BER performance over RLSDFE,IPNLMS-DFE,and CE-DFE.Compared with the RLS-DFE,the BER,after five iterations,is reduced from 0.0076 to 0.0037 in the 8–12 k Hz band and from 0.1516 to 0.1145 in the 13–17 k Hz band at a distance of 2000 m.Thus,the proposed algorithm makes it possible to apply MLSE in UAC in practical scenarios.
文摘With the rapid advancement of computing and information technology at the turn of the 21st century,the power of data collection and processing has multiplied tremendously.Based on this a game-changing advancement,science is at the advent of the “fourth paradigm”of massive data plus artificial intelligence,in which the efficiency of scientific research is continuously improved,research time is shortened,and research cost is reduced[1].
基金supported by Volkswagen Foundation(Grant Ref:60420897,Dr Patrice Savadogo)CGIAR(Consultative Group on International Agricultural Research)Research Program on Dry lands(CRP 1.1).(Headquarters in Jordan)
文摘Insufficient knowledge of the germination ecology of local species is one of the main constraints to restoration of degraded rural lands. We tested seeds from fourteen Sudanian savanna species targeted for restoration for their response to two different pretreatments(conventional and prolonged acid pretreatments) and two different storage conditions(ambient room conditions and refrigerator at 4 C). For 6 of the studied species, longer soaking in sulphuric acid significantly improved germination rates and also reduced the germination time of some species. Storage condition, in general did not affect germination rates except for two species where cool storage depressed germination. The practical implication is that, for the species tested, when mature seeds are collected for plantation in the upcoming rainy season, there is no need to invest in infrastructure and energy for storing in cold conditions.The study also revealed that in general when seeds are stored in ambient conditions from the time of collection up to seeding time, although germination rate does not increase, germination time is shortened and this could be of great interest in synchronizing germination in real field conditions.
文摘Common abbreviations,acronyms and short names are listed below.These shortened forms,and otherabbreviations not in this list,should always be defined at first usage in both abstract and text.Some of themare well-known and can be used directly without confusion.
文摘Sciatica is a commonly seen illness withmultifactorial pathogenesis. The symptomsare characterized by pain in the affected legand functional disabilities. Since 1986, theauthor has adopted acupuncture at thelumbar Jiaji points (Extra 21) for treatmentof the condition with marked efficacy. Thecure rate has been high and the treatmentcourse greatly shortened, as reported in thefollowing.
文摘In this paper, we observed the effect of moxibustion on the positive reactionin uroprotein test, the time of hypouresis and the change of B-mode echography of kidney of thepatient with EHF. We measured the change of BUN content in serum of the rat infected withEHF virus (EHFV) before and after moxibustion. Results showed moxibustion could shortenthe time of hypouresis, promote the removal of positive reaction in the uroprotein test, decreasethe content of BUN in serum and reduce the swelling of kidney. All these results suggested thatmoxibustion might have the effect on protecting kidney function in some degree.
文摘There are two kinds of generating equipment in a firmly con-nected power network,one is water power plants(shortenedas“water power”,below),the other is thermal power plants(includingcoal-fired,oil-fired and nuclear power plants,but the analysis in thisarticle is based mainly on coal-fired power generation.And they willbe shortened as“thermal power”below).As far as power output isconcerned,when the share of water power installed capacity
文摘Objective:To investigate the Effects of Metoprolol on QTDispersion(QTd)and Heart Rate Variability(HRV)in Patientswith Coronary Artery Disease(CAD).Methods:The changes of QTd and HRV were investigatedbefore and after administrating Metoprolol(93.75±22.8mg/d)for two weeks in the 24 patients with CAD.Results:Compared with healthy adults,the QTd,QTcd andQTmax were significantly higher(p【0.05)in the patients withCAD,and the QTmin lengthened and the QTd shortened whentaking Valsalva s respiration,the SDNNindex,rMSSD,PNN50and HF increased significantly(p【0.01),and LF/HF ratiodecreased,but the SDNN,SDANN and LF did not change afteradministrating Metoprolol.In addition,the QTmin shortened,the QTd,QTcd lengthened significantly(p【0.05),but the QTmaxhad no significant change after administratingMetoprolol(p】0.05).Condusions:The results suggest that the sympathetic nervecould regulate the repolarization speed of the normalventricular myocardium,and change the QTd in the patientswith CAD,Metoprolol relieve not only angina pectoris byincreasing efficiently the blood supply,and decreasing theoxygen demand of the myocardium,but also shorten markedlythe QTd.
文摘Shortening is one of important word formations which demands attentions of both teachers and students. The paper first briefly introduces shortening words in English into clipped words, initialisms, acronyms and blends,and then it mainly explores the reasons why shortening words appear and become popular.
文摘920024 The TCM-WM treatment of severerenal failure inpatients with epidemichemorrhagic fever.LIU Junbin (刘俊彬),et al.Dept Infect Dis,Xijing Hosp,Xi’an,710032.ChinIntegr Tradit & West Med 1991;11(8):484-485.This article reports the treatment of 23 cases(with the control group 20 cases) of severe renalfailure in patients with epidemic hemorrhagicfever (EHF)by integrated traditional Chinesemedicine arid western medicine (TCM-WM),i.e.the renal protective decoction and modernmedical treatment during the period of 1988~1989.The effects were found as follows:(1)
文摘920690 A clinical study of the relationshipbetween regulation of electrolytes andsubsidence of cirrhotics ascites. HOUShuqin (侯淑琴), et al. Dept Gastroenterol, Nan-fang Hosp, 1st Med Univ, PLA, Guangzhou.Chin J Digest 1992; 12(2): 84-86. Mechanism of many diuretics is based
文摘Two encouraging results were reportedby the end of 1988.Firstry,a new pro-cess for extraction of RE elements froman ion-adsorption type RE mineral;se-condly,serial production of hi-puritySc has been effective.There are several varieties of ion-adsorption type RE minerals occur inSouth China.They differ in RE contents,
基金co-supported by the President Fund and Innovation Program of Chinese Academy of Sciences(no.:kzcx2-yw-104)the Chinese National Science Foundation grants(no.:40334038)the Science and Technology Key Project of Ministry of Education of China(no.:306016).
文摘The Qaidam Basin, located in the northern margin of the Qinghai-Tibet Plateau, is a large Mesozoic-Cenozoic basin, and bears huge thick Cenozoic strata. The geologic events of the Indian- Eurasian plate-plate collision since -55 Ma have been well recorded. Based on the latest progress in high-resolution stratigraphy, a technique of balanced section was applied to six pieces of northeast- southwest geologic seismic profiles in the central and eastern of the Qaidam Basin to reconstruct the crustal shortening deformation history during the Cenozoic collision. The results show that the Qaidam Basin began to shorten deformation nearly synchronous to the early collision, manifesting as a weak compression, the deformation increased significantly during the Middle and Late Eocene, and then weakened slightly and began to accelerate rapidly since the Late Miocene, especially since the Quaternary, reflecting this powerful compressional deformation and rapid uplift of the northern Tibetan Plateau around the Qaidam Basin.
基金supports by the Basic Research Foundation of the Institute of Geomechanics,CAGS,China (DZLXJK200703)the National Natural Science Foundation of China(40342015)+1 种基金SinoProbe-Deep Exploration in China(SinoProbe-08)the National Science Foundation(USA) Instrumentation and Facilities Program (EAR-0443387)
文摘The eastern margin of the Qaidam Basin lies in the key tectonic location connecting the Qinling, Qilian and East Kunlun orogens. The paper presents an investigation and analysis of the geologic structures of the area and LA-ICP MS zircon U-Pb dating of Paleozoic and Mesozoic magmatisms of granitoids in the basement of the eastern Qaidam Basin on the basis of 16 granitoid samples collected from the South Qilian Mountains, the Qaidam Basin basement and the East Kunlun Mountains. According to the results in this paper, the basement of the basin, from the northern margin of the Qaidam Basin to the East Kunlun Mountains, has experienced at least three periods of intrusive activities of granitoids since the Early Paleozoic, i.e. the magmatisms occurring in the Late Cambrian (493.1±4.9 Ma), the Silurian (422.9±8.0 Ma-420.4±4.6 Ma) and the Late Permian-Middle Triassic (257.8±4.0 Ma-228.8+1.5 Ma), respectively. Among them, the Late Permian - Middle Triassic granitoids form the main components of the basement of the basin. The statistics of dated zircons in this paper shows the intrusive magmatic activities in the basement of the basin have three peak ages of 244 Ma (main), 418 Ma, and 493 Ma respectively. The dating results reveal that the Early Paleozoic magmatism of granitoids mainly occurred on the northern margin of the Qaidam Basin and the southern margin of the Qilian Mountains, with only weak indications in the East Kunlun Mountains. However, the distribution of Permo-Triassic (P-T) granitoids occupied across the whole basement of the eastern Qaidam Basin from the southern margin of the Qilian Mountains to the East Kunlun Mountains. An integrated analysis of the age distribution of P-T granitoids in the Qaidam Basin and its surrounding mountains shows that the earliest P-T magmatism (293.6-270 Ma) occurred in the northwestern part of the basin and expanded eastwards and southwards, resulting in the P-T intrusive magmatism that ran through the whole basin basement. As the Cenozoic basement thrust system developed in the eastern Qaidam Basin, the nearly N-S-trending shortening and deformation in the basement of the basin tended to intensify from west to east, which went contrary to the distribution trend of N-S-trending shortening and deformation in the Cenozoic cover of the basin, reflecting that there was a transformation of shortening and thickening of Cenozoic crust between the eastern and western parts of the Qaidam Basin, i.e., the crustal shortening of eastern Qaidam was dominated by the basement deformation (triggered at the middle and lower crust), whereas that of western Qaidam was mainly by folding and thrusting of the sedimentary cover (the upper crust).