Description of two new species of Pseudoaliinostoc(Nostocales,Cyanobacteria)from China based on the polyphasic approach

Two cyanobacterial strains CHAB5870 and CHAB5871 morphologically identifi ed as Nostoc-like species were isolated from different habitats in China,and they were phylogenetically and taxonomically characterized based on a polyphasic approach combining morphological,ecological,and molecular data.In the 16S rRNA gene phylogeny inferred using maximum likelihood,maximum-parismony,and bayesian inference methods,these two strains clustered within the Pseudoaliinostoc clade.The 16S rRNA gene sequences of these two strains displayed≥95.5%and≤98%similarity to Pseudoaliinostoc species,which indicated them to represent new species of the genus Pseudoaliinostoc.Furthermore,the unique pattern of D1-D1′and Box-B helix of the 16S–23S rRNA internal transcribed spacer(ITS)secondary structure also revealed that two strains represented novel species.These results supported the establishment of two new Pseudoaliinostoc species with the name P.jiangxiense sp.nov.and P.yunnanense sp.nov.

Neomicrocoleus gen.nov.(Microcoleaceae,Oscillatoriales),a novel cyanobacterial genus from benthic mats in a water channel

A new filamentous cyanobacterial strain(CHAB 4127)was successfully isolated from the algal mat during the field investigation of the open channel from Luanhe River to Tianjin,China.The polyphasic approach combining morphological,ultrastructural,ecological,and molecular features was used to characterize this studied strain.The strain is morphologically similar to the Microcoleus-like cyanobacterial taxa under light microscopy,and the radial arrangement of thylakoids is also consistent with that of Microcoleus-like groups.The phylogenetic position of CHAB 4127 based on 16S rRNA gene sequences,is shown to be clearly clustered into an independent clade with the newly established genus Microcoleusiopsis.The maximum similarity of 16S r RNA gene of the studied strain with other existing related cyanobacterial taxa is 93.97%,and the ITS secondary structures is also obviously different from other members of Microcoleaceae.Based on all the above evidence,we proposed the establishment of this novel cyanobacterial genus as Neomicrocoleus,with its type species,Neomicrocoleus tianjinensis.

The DASA Graben in Northern Niger:A Case of a Paleo-Mesozoic Basin Evolving from Uplifting to Rifting

The N70°DASA graben is a closed-rift that seems to be the deepest part of the Tim MersoïBasin,which is located in the northwestern part of Niger in West Africa.It contains more than 805 m of Paleozoic-Mesozoic sediments.The tectonic subsidence and uplifting was calculated by using well log data and deducing the variations in sedimentary thicknesses over time.Geological mapping and tectono-sedimentary analysis indicate that the structural evolution of the DASA trough is characterized by two major periods:(1)the first period was marked by an uplift stage ranging from the Carboniferous to the Permian.It was typified by a weak subsidence rate(3.45 m/Ma on average),under a transpressive tectonic regime,with a decrease in the thickness of the sedimentary series along the axial zone of the trough,and an increase of the thickness towards the border areas;(2)the second period was characterized by a higher subsidence rate(4.11 m/Ma on average)related to a change in the tectonic regime.It was marked by a rifting stage preserved over a long period,subjected to an extensive tectonic regime,from the Triassic to the lower Cretaceous,during which the highest thicknesses of the sedimentary series developed in the axial zone of the graben.The structural and sedimentological features defined the DASA graben as a particular type of syn-sedimentary basin evolving from a transpressive tectonic regime during the Paleozoic to an extensive tectonic regime during the Lower Mesozoic.Thus,the second period marked by an extensional regime would probably be related to the opening of the first stages of the Atlantic Ocean.

高速四相时钟电路设计

基于IHP 130 nm SiGe BiCMOS工艺,设计了一个由基于RC网络相移特性的polyphase移相器和差分时钟缓冲器组成的2 GHz四相时钟电路。因单阶polyphase带宽不足而设计了三阶polyphase级联提高带宽。采用HBT(heterojuntion bipolar transistor)差分时钟缓冲取代MOS(metal oxide semiconductor)单端时钟缓冲,实现更高时钟频率的同时,差分结构也能有效抑制流入采样电容的时钟信号馈通。各模块版图设计均采用高度对称结构来消除相位误差。仿真结果表明,差分输入2 GHz正弦波时,可输出4路相位相差90°方波时钟信号,时钟上升时间约15 ps,4路时钟相位误差小于2.2°,应用到4通道采样保持电路后可成功采样和保持8 GHz正弦输入信号。

Polyphase Tectonic Events and Cenozoic Basin-Range Coupling in the Tianshan Belt,Northwestern China

Studies show that the Tianshan orogenic belt was built in the late stage of the Paleozoic, as evidenced by the Permian red molasses and foreland basins, which are distributed in parallel with the Tianshan belt, indicating that an intense folding and uplifting event took place. During the Triassic, this orogenic belt was strongly eroded, and basins were further developed. Starting from the Jurassic, a within-plate regional extension occurred, forming a series of Jurassic-Paleogene extensional basins in the peneplaned Tianshan region. Since the Neogene, a collision event between the Indian and the Eurasian plates that took place on the southern side of the Tianshan belt has caused a strong intra-continental orogeny, which is characterized by thrusting and folding. Extremely thick coarse conglomerate and sandy conglomerate of the Xiyu Formation of Neogene System were accumulated unconformably on the Tianshan piedmont. Studies have revealed that the strong compression caused by the Indian-Eurasian collision had a profound influence over the orogenic belt in the hinterland, and MesozoiC-Cenozoic brittle deformed structures superposed on the ductile deformed Paleozoic rocks. The Mesozoic extensional basins were converted into Cenozoic compressional basins. The deformation in the basins is featured by step thrusts and fault-related folds. Statistics of joints show that the principal compressive stress since the Neogene is in a N-S direction. Meanwhile, owing to the underthrusting of the basin toward the orogenic belt, the Paleozoic strata were thrust on the Meso-Cenozoic rocks as tectonic slices, revealing distinct kinematic features in different geologic units. The basin-range coupling zones are characterized by intensive compression, folding and thrusting, accompanied by local sub-E-W-trending strike-slip faults. In the Tianshan region, Cenozoic thrusting is the most common basin-range coupling mode. The folding and faulting of Mesozoic sedimentary rocks, spontaneous combustion of Jurassic coal layers and formation of sintered rocks, the Cenozoic earthquakes and active faulting, and the unique mosaic pattern of basin-range framework of Xinjiang are all products of tectonism since the Neogene.

Polyphase Deformation of the Weihai-Rongcheng UHP Unit Rocks,NE Sulu:Insights into the Tectonic Evolution of the Dabie-Sulu UHP and HP Belts,China

Different scales of structural data reveal a complex deformation history of ultrahigh- pressure （UHP） rocks exposed in the Weihai-Rongcbeng area, NE Sulu （northern Jiangsu-eastern Shandong）, eastern China. Excluding pre-UHP deformations, at least five major sequential deformational stages （D1-Ds） are recognized. The first deformation （DO produced a weak foliation and lineation in massive eclogites. The foliated eclogite with a dominant foliation containing a stretching and mineral lineation was developed during the I）2 deformation. Both the D1 and D2 deformations occurred under UHP metamorphic conditions, and are well preserved in the eclogite bodies. D3 structures which developed shortly after the formation of granulite/amphibolite facies symplectites are characterized by imbricated associations marked by a regional, steeply dipping foliation, compositional layering, eclogite boudinage, isoclinal folds and reverse ductile shear zones. The D3 deformation was accompanied by decompressional partial melting. A regional, gently dipping amphibolite facies foliation and stretching lineation, low-angle detachments, and dome- and arc-shaped structures formed during the D4 deformation stage dominate to some degree the map pattern of the Weihai-Rongcbeng UHP domain. The last stage of deformation （Ds） gave rise to the final exhumation of the UHP rocks. Ds is characterized by development of brittle-dominated high-angle faulting associated with emplacement of large volmnes of undeformed granite plutons and dykes dated at 134-100 Ma. The deformational and metamorphic sequence followed by the UHP rocks in the Weihai-Rongcheng area is similar to that studied in the entire Dabie-Sulu UHP and HP metamorphic belts from microscopic to mapping scale. Based on structural data, combined with available petrographic, metamorphic and geochronological data, a speculative tectonic evolutionary model for the Dabie-Sulu UHP and IIP belts is proposed, involving continental subduction/collision between the Sino-Korean and Yangtze cratons and subsequent polyphase exhumation histories of the UHP and IIP metamorphic rocks.

FPGA-Based Efficient Programmable Polyphase FIR Filter

The modelling, design and implementation of a high-speed programmable polyphase finite impulse response (FIR) filter with field programmable gate array (FPGA) technology are described. This FIR filter can run automatically according to the programmable configuration word including symmetry/asymmetry, odd/even taps, from 32 taps up to 256 taps. The filter with 12 bit signal and 12 bit coefficient word-length has been realized on a Xilinx VirtexⅡ-v1500 device and operates at the maximum sampling frequency of (160 MHz.)

Hardware Architecture of Polyphase Filter Banks Performing Embedded Resampling for Software-Defined Radio Front-Ends

In this paper, we describe resourceefficient hardware architectures for softwaredefined radio （SDR） frontends. These architectures are made efficient by using a polyphase channelizer that performs arbitrary sample rate changes, frequency selection, and bandwidth control. We discuss area, time, and power optimization for field programmable gate array （FPGA） based architectures in an Mpath polyphase filter bank with modified Npath polyphase filter. Such systems allow resampling by arbitrary ratios while simultaneously performing baseband aliasing from center frequencies at Nyquist zones that are not multiples of the output sample rate. A nonmaximally decimated polyphase filter bank, where the number of data loads is not equal to the number of M subfilters, processes M subfilters in a time period that is either less than or greater than the Mdataload ＇ s time period. We present a loadprocess architecture （LPA） and a runtime architecture （RA） （based on serial polyphase structure） which have different scheduling. In LPA, Nsubfilters are loaded, and then M subfilters are processed at a clock rate that is a multiple of the input data rate. This is necessary to meet the output time constraint of the down-sampled data. In RA, Msubfilters processes are efficiently scheduled within Ndataload time while simultaneously loading N subfilters. This requires reduced clock rates compared with LPA, and potentially less power is consumed. A polyphase filter bank that uses different resampling factors for maximally decimated, underdecimated, overdecimated, and combined upand downsampled scenarios is used as a case study, and an analysis of area, time, and power for their FPGA architectures is given. For resourceoptimized SDR frontends, RA is superior for reducing operating clock rates and dynamic power consumption. RA is also superior for reducing area resources, except when indices are prestored in LUTs.

Polyphase Filter Banks for Embedded Sample Rate Changes in Digital Radio Front-Ends

This paper presents efficient processing engines for software-defined radio （SDR） front-ends. These engines, based on a polyphase channelizer, perform arbitrary sample-rate changes, frequency selection, and bandwidth control. This paper presents an M-path polyphase filter bank based on a modified N-path polyphase filter. Such a system allows resampling by arbitrary ratios while performing baseband aliasing from center frequencies at Nyquist zones that are not multiples of the output sample rate. This resampling technique is based on sliding cyclic data load interacting with cyclic-shifted coefficients. A non-maximally-decimated polyphase filterbank （where the number of data loads is not equal to the number of M subfilters） processes M subfilters in a time period that is less than or greater than the M data loads. A polyphase filter bank with five different resampling modes is used as a case study for embedded resamp/ing in SDR front-ends. These modes are （i） maximally decimated, （ii） Under-decimated, （iii） over-decimated, and combined up- and down-sampling with （iv） single stride length, and （v） multiple stride lengths. These modes can be used to obtain any required rational sampling rate change in an SDR front-end based on a polyphase channelizer. They can also be used for translation to and from arbitrary center frequencies that are unrelated to the output sample rates.

Structural Evolution of the Western Makran

The Makran represents a huge accretionary wedge in SE Iran that resulted from the long-lasting subduction of the Neotethys Ocean since the Mesozoic. From west to east, this accretionary wedge extends ~1000 km between the Minab Fault in Iran, and the Ornach-Nal Fault in Pakistan. The ongoing oceanic subduction characterizes this belt between the Iranian Plateau and the Tibetan Plateau, both of which were generated by collision of Eurasian with the Arabian and Indian plates, and provides an ideal target to recover the tectonic history of subduction. The western Makran located in Iran can be subdivided into four units: The North Makran ophiolitic mélange, the Inner Makran, the Outer Makran, and the Coastal Makran. Based on our detailed structural analysis and geochronological dating, we obtain several new results that can help us to better understand the structural evolution:(1) The North Makran ophiolitic mélange includes thick piles of volcanic rocks and limestone that directly cover the mantle peridotite, so it is likely to be part of an Early Cretaceous volcanic arc by our zircon dating at ~115 Ma on mafic intrusions;(2) The entire western Makran underwent three phases of deformation. D1 is characterized by top-to-the S/SW thrusting as evidence by southward emplacement of the ophiolitic mélange onto the Eocene sedimentary rocks. D2 deformation strongly folded the pre-late Miocene/early Pliocene strata that also corresponds to the final emplacement of the ophiolite to the surface. D3 structures extends in a N-S direction with top-to-the W kinematics that overthrust the Miocene sandstone onto the Pliocene fluvial sediments along the Minab Fault;(3) Combined with geological and geochronological relationship, D1 occurred at ~45-35 Ma, D2 initiated in middle Miocene and ended with a regional late Miocene-early Pliocene uncomformity, and D3 structures are still active as the subduction continues.

GENERALIZED FLOW LAWS OF POLYPHASE ROCKS: AN OVERVIEW

Rheological properties of polyphase rocks play an important role in the dynamics of the lithosphere and asthenosphere. However, such fundamental issues have not been well resolved. A theoretical analysis has been made to develop expressions for the flow laws of polyphase rocks in terms of the volume fractions and flow laws of their constituent phases. The flow strengths predicted by the proposed model for common crustal and upper mantle rocks such as granite, diorite, diabase and lherzolite, and for synthetic two phase composites such as forsterite enstatite and water ice ammonia dehydrate aggregates are in good agreement with previously determined experimental values. The proposed theoretical model allows one to calculate, to the first approximation, the flow laws of a large number of polyphase rocks at geologic conditions based on the experimentally determined flow laws of a relatively small number of monomineralic aggregates.

Polyphase Multipole Resolvers for Improving Ripple Torque

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A NEW QUADRATURE SAMPLING APPROACH FOR ARBITRARY BANDPASS SIGNAL WITHIN BASEBAND SAMPLING RATE

A new quadrature sampling technique for arbitrary bandpass signal within baseband sampling rate is presented. The input bandpass signal whose carrier frequency lies in the A/D baseband sampling rate is first decimated by factor 2 and modulated by (- 1)n, and then is interpolated by a linear phase FIR all-pass filter, finally the modulated complex envelope of bandpass signal can be produced.

AN EFFICIENT IMPLEMENTATION ARCHITECTURE FOR WIDE-BAND DIGITAL DOWNCONVERSION

The wide-band digital receiving systems require digital downconversion(DDC) with high data rate and short tuning time in order to intercept the narrow-band signals within broad tuning bandwidth. But these requirements can not be met by the commercial DDC. In this paper an efficient implementation architecture is presented. It combines the flexibility of DFT tuning with the efficiency of the polyphase filter bank decomposition. By first decimating the data prior to filtering and mixing, this architecture gives a better solution to the mismatch between the lower hardware speed and high data rate. The computer simulations show the feasibility of this processing architecture.

A Characterization of MRA Based Wavelet Frames Generated by the Walsh Polynomials

Extension Principles play a significant role in the construction of MRA based wavelet frames and have attracted much attention for their potential applications in various scientific fields. A novel and simple procedure for the construction of tight wavelet frames generated by the Walsh polynomials using Extension Principles was recently considered by Shah in [Tight wavelet frames generated by the Walsh poly- nomials, Int. J. Wavelets, Multiresolut. Inf. Process., 11（6） （2013）, 1350042]. In this paper, we establish a complete characterization of tight wavelet frames generated by the Walsh polynomials in terms of the polyphase matrices formed by the polyphase components of the Walsh polynomials.

PARAMETERIZATION OF SYMMETRIC SCALING FUNCTIONS

In this paper,the factorization for filters with length Km of scaling functions into simple blocks is considered.

Metamorphic stages in mountain belts during a Wilson cycle:A case study in the central Sanandaj-Sirjan zone(Zagros Mountains,Iran)

Polymetamorphic units are important constituents of continent-continent collisional orogens,and rift metamorphic assemblages are often overprinted by subsequent metamorphism during subduction and collision.This study reports the metamorphic conditions and evolution of the Dorud-Azna metamorphic units in the central part of the Sanandaj-Sirjan zone(SSZ),Iran.Here,new geothermobarometry results are integrated with ^(40)Ar/^(39)Ar mineral and Th-U-Pb monazite and thorite ages to provide new insight of polyphase metamorphism in the two different basement units of the SSZ,the lower Galeh-Doz orthogneiss and higher Amphibolite-Metagabbro units.In the Amphibolite-Metagabbro unit,staurolite micaschist underwent a prograde P-T evolution from 640±20℃/6.2±0.8 kbar in garnet cores(M1)to 680±20℃/7.2±1.0 kbar in garnet rims(M2).Three Th-U-Pb monazite ages of 306±5 Ma,322±28 Ma and 336±39 Ma from the garnet-micaschists testify the Carboniferous age of M1 metamorphism.In the same unit,the metagabbro records P-T conditions of 4.0±0.8 kbar and 580±50℃ in the(magmatic)amphibole core(Late Carboniferous intrusion)to 7.5±0.7 kbar and 700±20℃ in the amphibole rim indicating a prograde P-T path during subsequent burial(M1).New ^(40)Ar/^(39)Ar dating of white mica from the staurolite micaschist yielded a staircase pattern ranging from 36±12 Ma to 170±2 Ma.This implies polymetamorphism with a minimum Late Jurassic cooling age through the Ar retention temperature of ca.425±25℃ after M2 metamorphism and a Paleogene low-grade metamorphic overprint(M3),while ^(40)Ar/^(39)Ar white mica dating of garnet micaschist yielded a plateau age of 137.84±0.65 Ma.We therefore interpret the amphibolite-grade metamorphism M2 to have predated 170 Ma and is likely between 180 and 200 Ma.Furthermore,it is overprinted at about 36 Ma under retrogressive low-grade M3 metamorphism(at temperatures of~350-240℃)during final shortening and exhumation.In the underlying Galeh-Doz unit,the Panafrican granitic orthogneiss intruded at P-T conditions of 3.2±4 kbar and 700±20℃,then it was metamorphosed and deformed at 600±50℃ and 2.0±0.8 kbar(metamorphic stage M1)prior to Late Carboniferous intrusion of mafic dikes.^(40)Ar/^(39)Ar dating of amphibole from the Galeh-Doz orthogneiss gave plateau-like steps between 260 and 270 Ma,representing the age of cooling through ca.500℃ after the M1 metamorphic event.Interestingly,the results of this study demonstrate polyphase metamorphic histories in both the Galeh-Doz orthogneiss and Amphibolite-Metagabbro units at different P-T conditions and final thickskinned Paleogene emplacement of these units over the underlying low-grade metamorphic June Complex.Our findings suggest that both units are affected by high-T/low-P Late Carboniferous orogenic metamorphism along with the bimodal magmatism,as result of rifting.We propose that the Early Jurassic amphibolite-grade M2 metamorphism of the SSZ is correlated with the initial subduction of the Neotethyan Ocean.Eventually,the investigated units reflect various stages of a Wilson cycle,from rifting to initiation of the subduction in final plate collision.

Symbol Synchronization of Single-Carrier Signal with Ultra-Low Oversampling Rate Based on Polyphase Filter

An efficient single-carrier symbol synchronization method is proposed in this paper,which can work under a very low oversampling rate.This method is based on the frequency aliasing squared timing recovery assisted by pilot symbols and time domain filter.With frequency aliasing squared timing recovery with pilots,it is accessible to estimate timing error under oversampling rate less than 2.The time domain filter simultaneously performs matched-filtering and arbitrary interpolation.Because of pilot assisting,timing error estimation can be free from alias and self noise,so our method has good performance.Compared with traditional time-domain methods requiring oversampling rate above 2,this method can be adapted to any rational oversampling rate including less than 2.Moreover,compared with symbol synchronization in frequency domain which can operate under low oversampling rate,our method saves the complicated operation of conversion between time domain and frequency domain.By low oversampling rate and resource saving filter,this method is suitable for ultra-high-speed communication systems under resource-restricted hardware.The paper carries on the simulation and realization under 64QAM system.The simulation result shows that the loss is very low(less than 0.5 dB),and the real-time implementation on field programmable gate array(FPGA)also works fine.

A FAST PARAMETER ESTIMATION ALGORITHM FOR POLYPHASE CODED CW SIGNALS

A fast parameter estimation algorithm is discussed for a polyphase coded Continuous Waveform(CW) signal in Additive White Gaussian Noise(AWGN).The proposed estimator is based on the sum of the modulus square of the ambiguity function at the different Doppler shifts.An iterative refinement stage is proposed to avoid the effect of the spurious peaks that arise when the summation length of the estimator exceeds the subcode duration.The theoretical variance of the subcode rate estimate is derived.The Monte-Carlo simulation results show that the proposed estimator is highly accurate and effective at moderate Signal-to-Noise Ratio(SNR).

DESIGN OF POLYPHASE WAVE DIGITAL FILTERS WITH APPROXIMATELY LINEAR PHASE

It is well known that IIR digital filters require quite fewer computations,comparedwith FIR filters,in order to meet stringent magnitude specifications when the phase distortioncan be tolerated.An approximately linear phase,however,can be also obtained with the IIRfilter by making use of a technique without increasing the complexity.Based on a certain numberof attenuation zeros in the pass band,a new approach is developed for the design of polyphasewave digital filters with exact magnitude responses and Chebyshev approximation of the desiredphase responses.The minimum number of attenuation zeros is estimated,and some examples areincluded.