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1.
We explore the diachronic development of verbal reduplication in Ancient Egyptian (Afro-Asiatic) by systematically comparing reduplicative stem formations in Old Egyptian (2500–2000 BC) and in Coptic Egyptian (3rd–12th c. AD). Old Egyptian is a language with a rich inventory of reduplication patterns, which have been reduced in the course of almost four thousand years of uninterrupted language history. Coptic retains only a limited number of reduplicative stem formations, frequently with concomitant loss of the simple stem. We show that the decreasing productivity of verbal reduplication in the language correlates with broad morphological and syntactic changes in the verbal domain.  相似文献   

2.
The exposition comprises three parts. Part 1 surveys the Indo-European reduplication patterns (RPs) that have been lost in Slavic and Baltic: the languages show little or no evidence of inherited RPs in present and perfect formations, and in intensive verbs (Sect. 2.1), but some vestiges of reduplication in nouns can be identified (Sect. 2.2). Part 2 describes innovated RPs in the Slavic verb; they can be posited on the basis of scanty evidence that has survived the Late Common Slavic loss of coda obstruents. Part 3 describes Baltic innovations reflected in Lithuanian: reduplicative root formations (Sect. 4.1), several minor lexicalized RPs (Sect. 4.2.), and the para-lexical part of speech called eventives (Sect. 4.3). Their content categories, types of expression, patterns of iconicity, and grammatical function are analysed and exemplified in some detail. It is suggested that formations such as these may form the natural background for the creation of new patterns of morphological expression including patterns of reduplication.  相似文献   

3.
Summary HPLC was combined with a packable microbore guard column to obtain the adsorption isotherm of lysozyme in a Hydrophobic Interaction Chromatography system. The equipment configuration enabled isotherm determination of the protein on a relatively low pressure chromatographic media (TosoHaas 650M Phenyl).Notation Cm,i is the mobile phase concentration of protein. (M/L3 (liquid)) - Cm,0 =0 - Cs,i is the stationary phase concentration of protein. It is the concentration of protein on the chromatographic media. (M/L3 (solid)) - Cs,0 =0 - M,L is the dimensions mass and length - Vr,i is the retention volume of the peak front that corresponds to a mobile phase protein on the concentration Cm,i. (L3 (liquid)) - i i is a counter that is used to keep track of Cm, Cs, and Vr.For example, i=1 in the term Cm,i denotes the first, and lowest, mobile phase protein concentrations are described by higher values of i. - Vd is the system dead volume. It consists of all of the system volume that the mobile phase "sees" or contacts, includingchromatographic media interparticle and pore volume. (L3 liquid) - Vs the stationary phase volume. Vs is the nonporous bead volume. For porous beads, Vs is the bead volume - the porevolume. (L3 (solid)) - Ve is the empty column volume. (L3 liquid) - Vm is the packed column mobile phase volume and consists of the pore volume and the excluded volume. (L3 (liquid)) - Ve system is the empty column system volume. (L3 (liquid)) - Vfrit the volume of mobile phase that fills the column frits. (L3 (liquid)) - Vwoc the system volume without the column connected. (L3 (liquid))  相似文献   

4.
Larry M. Hyman 《Morphology》2009,19(2):177-206
In this study I present a comparative and historical analysis of “frequentative” Bantu verb-stem reduplication, many of whose variants have been described for a number of Eastern and Southern Bantu languages. While some languages have full-stem compounding, where the stem consists of the verb root plus any and all suffixes, others restrict the reduplicant to two syllables. Two questions are addressed: (i) What was the original nature of reduplication in Proto-Bantu? (ii) What diachronic processes have led to the observed variation? I first consider evidence that the frequentative began as full-stem reduplication, which then became restricted either morphologically (by excluding inflectional and ultimately derivational suffixes) and/or phonologically (by imposing a bisyllabic maximum size constraint). I then turn to the opposite hypothesis and consider evidence and motivations for a conflicting tendency to rebuild full-stem reduplication from the partial reduplicant. I end by attempting to explain why the partial reduplicant is almost always preposed to the fuller base.  相似文献   

5.
6.
Cytotoxic lymphocytes (CTL) were generated betweenIg-1-congenic strains BALB/c(H-2d,Ig-1a) andC.B-17(H-2d,Ig-1b) by cross-immunization in both directions and rechallenge in vitro. The effector cell populations specifically lysed target cells sharing both theH-2 haplotype and theIg-1 allele of the sensitizing strain. B- and T-cell blasts were equally good targets, suggesting thatH-2-restricted cytotoxic lymphocytes are not directed against serologically defined conventional allotypic determinants, but probably against minor histocompatibility antigens controlled by genes linked to theIg-1 complex. Competition experiments using cold target cells from a series ofIg-1b-congenic strains of the BALB/c background (BAB-14, C.B-17, C.B-26) revealed two not yet described minor histocompatibility loci linked to theIg-1 complex: We could demonstrate that BALB/c anti-C.B-17 effector cells recognize at least two distinct antigenic determinants on C.B-17 target cells, but only one on target cells from BAB-14, which carries a recombinantIg-1 complex. From these results we conclude that one of the minor histocompatibility antigens, designated as H(CH), is encoded by a gene linked to the heavy-chain constant-region (CH) genes, whereas the second minor histocompatibility antigen, designated as H(VH), is coded for by a gene linked to the heavy-chain variable-region (VH) genes. These two new genetic markers may be useful for further analysis of the mouseIg-1 complex because the analysis of the H(CH) and H(VH) genes may facilitate the search for recombinants in that chromosomal region.  相似文献   

7.
Although a wide array of phonological properties seem to backcopy in reduplication, it is an open question whether reduplicative templates can backcopy as well. It has been argued that natural languages do not have reduplicative constructions where the base truncates to match the truncated reduplicant (McCarthy & Prince, 1994; McCarthy & Prince, 1999; Spaelti, 1997; inter alia). In Guarijio Abbreviated Reduplication (Miller, 1996), however, both copies of the reduplicative construction truncate, instantiating the pattern that has been claimed not to exist. This paper argues that the Guarijio case fills this typological gap. Although the data can be given a templatic backcopying analysis, this paper defends a Morphological Doubling Theory (MDT) analysis using cophonologies (Inkelas & Zoll, 2005). In MDT, Guarijio Abbreviated Reduplication results from the parallel imposition of a truncating cophonology in each copy of the reduplicative construction. Guarijio Abbreviated Reduplication is predicted to exist by MDT together with other documented cases of parallel phonological modification in reduplication. I am grateful to many people for helpful comments and suggestions, including Isabel Barreras Aguilar, Laura Downing, Nicholas Fleisher, Andrew Garrett, Jason Haugen, Larry Hyman, Yuni Kim, Teresa McFarland, David Mortensen, Mary Paster, Eric Raimy, and Timothy Thornes as well as the audience of the LSA 2005 Annual Meeting in Oakland. I would like to extend a special thanks to Alan Yu for his detailed comments and suggestions to latter versions of this paper. I am particularly indebted to Sharon Inkelas, for her generous advice, feedback, and numerous discussions throughout the development of this paper. I am also grateful to two anonymous reviewers for their comments and criticisms, and especially to Ingo Plag for his patience and detailed suggestions as editor. All remaining errors and omissions are mine. This study was made possible by fellowships by CONACYT (Consejo Nacional de Ciencia y Tecnología, México), the University of California Institute for Mexico and the United States (UCMEXUS) and Fulbright.  相似文献   

8.
To define the polymorphism and extent of the mouse immunoglobulin kappa (Igk) gene complex, we have analyzed restriction-enzyme digested genomic DNA from 33 inbred strains of mice with labeled DNA probes corresponding to 16 V x protein groups (1 of them previously undescribed) and the J k/C K region (V, variable; J, joining; C, constant). These probes detected between 1 and 25 distinct restriction enzyme fragments (REF) that appeared in up to eight polymorphic patterns, thus defining eight mouse Jgk haplotypes. The investigated portion of the V A repertoire was estimated to encompass between 60 and 120 discernable V k gene-containing REFs. In contrast to mouse V H gene families, several V k gene families defined by these probes appeared to overlap. This observation has implications for V k gene analyses by nucleic acid hybridization and raises the possibility that the V A gene complex is a continuum of related sequences.Abbreviations used in this paper C constant - Ig immunoglobulin - J joining - REF restriction enzyme fragment - RFLP restriction fragment length polymorphism - V variable  相似文献   

9.
Summary Penicillin G recovery is investigated in a continuous flotation column in the presence of different collectors which form a complex with penicillin. The performance of the penicillin recovery was investigated as a function of the mole ratio () of collector-to-penicillin and the aliphatic chain length of the collector. At =1 and low penicillin concentrations (e.g., 20 mg·1-1), high foam liquid concentrations (680 mg·l-1), low residue concentrations (12 mg·l-1) and high penicillin separation (56) can be attained. At =4 the separation increases to 150, and 95% of the penicillin can be recovered.Symbols Cp penicillin concentration in feed (mg·l-1) - CR penicillin concentration in outlet liquid (mg·l-1) - CS penicillin concentration in foam liquid (mg·l-1) - CS/CP penicillin enrichment (-) - CS/CR penicillin separation (-) - % Pen in S penicillin yield in foam liquid (%) - VV}S foam liquid volume flow (ml·min-1) - VV}P feed (ml·min-1) - VVN 2 nitrogen flow rate (ml·s-1) - temperature  相似文献   

10.
11.
Mutations in CACNA1C that increase current through the CaV1.2 L-type Ca2+ channel underlie rare forms of long QT syndrome (LQTS), and Timothy syndrome (TS). We identified a variant in CACNA1C in a male child of Filipino descent with arrhythmias and extracardiac features by candidate gene sequencing and performed functional expression studies to electrophysiologically characterize the effects of the variant on CaV1.2 channels. As a baby, the subject developed seizures and displayed developmental delays at 30 months of age. At age 5 years, he displayed a QTc of 520 ms and experienced recurrent VT. Physical exam at 17 years of age was notable for microcephaly, short stature, lower extremity weakness and atrophy with hyperreflexia, spastic diplegia, multiple dental caries and episodes of rhabdomyolysis. Candidate gene sequencing identified a G>C transversion at position 5731 of CACNA1C (rs374528680) predicting a glycine>arginine substitution at residue 1911 (p.G1911R) of CaV1.2. The allele frequency of this variant is 0.01 in Malays, but absent in 984 Caucasian alleles and in the 1000 genomes project. In electrophysiological analyses, the variant decreased voltage-dependent inactivation, thus causing a gain of function of CaV1.2. We also observed a negative shift of V1/2 of activation and positive shift of V1/2 of channel inactivation, resulting in an increase of the window current. Together, these suggest a gain-of-function effect on CaV1.2 and suggest increased susceptibility for arrhythmias in certain clinical settings. The p.G1911R variant was also identified in a case of sudden unexplained infant death (SUID), for which an increasing number of clinical observations have demonstrated can be associated with arrhythmogenic mutations in cardiac ion channels. In summary, the combined effects of the CACNA1C variant to diminish voltage-dependent inactivation of CaV1.2 and increase window current expand our appreciation of mechanisms by which a gain of function of CaV1.2 can contribute to QT prolongation.  相似文献   

12.
Protein recovery by continuous flotation   总被引:2,自引:0,他引:2  
Summary Bovine serum albumin (BSA) was recovered from aqueous solutions by foam flotation. The protein concentrations in foam liquid C S, in feed C Pand in residue C Rwere determined. The protein enrichment C S/CPand the separation C S/CRas well as the protein fraction in the foam liquid % BSA and foam liquid volume flow were determined as functions of the medium properties, operational conditions, and equipment parameters as well as concentrations of solid particles. At low protein concentrations in feed (e.g., C P=40 mg · l-1), and at 40° C, high performance was attained (C X=2,000 mg · l-1, C R=4.4 mg · l-1, C S/CP=50, C S/CR=450, 90% BSA. Continuous foam flotation is an efficient procedure for the recovery of low concentrations of proteins from liquid cultures.Abbreviations BSA bovine serum albumine - C P protein concentration in feed (mg · l-1) - C R protein concentration in residue (mg · l-1) - C S protein concentration in foam liquid (mg · l-1) - C S/CR protein separation (-) - C S/CP protein enrichment (-) - V P feed rate (ml · min-1) - V R residue flow rate (ml · min-1) - V S foam liquid volume flow (ml · min-1) - N number of theoretical stages in an ideal cascade (-) - temperature (° C) - mean residence time (min)  相似文献   

13.
Immuno-electron microscopy of negatively stained isolated tonoplast vesicles was used to quantify stress responses of the H+-transporting tonoplast ATPase (V0V1-ATPase; EC 3.6.1.1) of the C3/CAM intermediate Mesembryanthemum crystallinum L. and the C3 plant Hordeum vulgare L. This approach has the advantage that it relates quantitative adaptations at the level of membrane enzymes directly to membrane area and thus is independent of concomitant changes of relative amounts of other membrane proteins which may perturb conclusions when data are expressed on a tonoplast protein basis. It was shown that in M. crystallinum the amount of V0V1-ATPase per unit membrane area increased slightly with ageing and pronouncedly with salinity stress. In H. vulgare under salt stress there was an increase in V0V1-ATPase amount only in the highly salt tolerant cv. California Mariout and not in the moderately tolerant cv. Carina. This corroborates conclusions from earlier work, where results were expressed on a protein basis, although this was not to be expected a priori. In all comparative ecophysiological studies using tonoplast vesicles at least some key-point tests with the immunonegative staining technique should be included for the sake of prudence. The data obtained here via immunonegative staining of isolated tonoplast vesicles are in very close agreement with much earlier assessments of area and whole cell-related activities given by measurements of entire isolated vacuoles and morphometric analysis, which further corroborates the suitability of the approaches. The data presented here for the first time allow calculations of the coverage of the tonoplast surface of M. crystallinum with V0V1-ATPase holoenzyme protein and with total tonoplast protein, i.e. 1.5 to 2.3 . 10?15 g V0V1-ATPase per μm2 and 7.4 to 8.8 . 10?15 g protein per μm2, respectively.  相似文献   

14.
Vacuolar type rotary H+-ATPases (VoV1) couple ATP synthesis/hydrolysis by V1 with proton translocation by Vo via rotation of a central rotor apparatus composed of the V1-DF rotor shaft, a socket-like Vo-C (eukaryotic Vo-d) and the hydrophobic rotor ring. Reconstitution experiments using subcomplexes revealed a weak binding affinity of V1-DF to Vo-C despite the fact that torque needs to be transmitted between V1-DF and Vo-C for the tight energy coupling between V1 and Vo. Mutation of a short helix at the tip of V1-DF caused intramolecular uncoupling of VoV1, suggesting that proper fitting of the short helix of V1-D into the socket of Vo-C is required for tight energy coupling between V1 and Vo. To account for the apparently contradictory properties of the interaction between V1-DF and Vo-C (weak binding affinity but strict requirement for torque transmission), we propose a model in which the relationship between V1-DF and Vo-C corresponds to that between a slotted screwdriver and a head of slotted screw. This model is consistent with our previous result in which the central rotor apparatus is not the major factor for the association of V1 with Vo (Kishikawa and Yokoyama, J Biol Chem. 2012 24597-24603).  相似文献   

15.
Summary The concentration dependence of the foaming of aqueous bovine serum albumin (BSA) solutions with and without salt additives and that of the turbidity temperature, TT, of p-isononylphenol-10-glycolether in presence of KCl, MgSO4, or K4 [Fe(CN)6] were determined. The differences between the turbidity temperatures of the solutions with and without salt additives were used to calculate the apparent concentration BSA in the salt solutions and to estimate their foaming. The measured and calculated foaminesses agree well.Symbols BSA Bovine Serum Albumin - C concentration - CBSA concentration of BSA - Csalt salt concentration - CO actual protein concentration in the absence of a salt - C1 apparent protein concentration in the presence of a salt - C' NP-10 concentration - k constant in Eq. (4) - Tcorr correction for TTO of the salt-free NP-10 solution - TT turbidity temperature - Vs equilibrium volume of the foam above the liquid layer - Vtg volumetric gas flow rate - foaminess - NP-10 p-isononylphenol-10-glycolether  相似文献   

16.
S H White 《Biophysical journal》1970,10(12):1127-1148
A method is described for measuring the specific capacitance (Cm) of lipid bilayer membranes with an estimated experimental error of only 1%. The gross capacitance was measured with an AC Wheatstone bridge and a photographic technique was used to determine the area of thin membrane. The results of measurements on oxidized cholesterol-decane membranes formed in 1 × 10-2 M KCl show that Cm depends upon temperature, voltage, time, and the age of the bulk membrane solutions. For a freshly thinned membrane (from 5 week old solution), Cm increases exponentially from an initial value of 0.432 ±0.021 (SD) μF/cm2 with a time constant of ~15 min. A 100 mv potential applied across the membrane for 10-20 min prior to making measurements eliminated this time dependence and produced final-state membranes. Cm of final-state membranes depends upon applied voltage (Va) and obeys the equation Cm = C0 + βVa2 where Va VDC + VrmsAC. C0 and β depend upon temperature; C0 decreases linearly with temperature while β increases linearly. At 20°C, C0 = 0.559 ±0.01 (SD) μF/cm2 and β = 0.0123 ±0.0036 (SD) (μF/cm2)/(mv2) and at 34°C, C0 = 0.472 ±0.01 and β = 0.0382 ±0.0039. These variations in Cm are interpreted as resulting from thickness changes. The possibility that they result from diffuse layer and/or membrane dielectric phenomena is discussed and found to be unlikely. The results are discussed in terms of membrane stability by constructing hypothetical potential energy vs. thickness curves.  相似文献   

17.
Nominal plural formation in Seenku involves two surface changes: fronting of the final vowel and raising of the final tone. Diachronically, the plural patterns likely derive from a suffix *- Open image in new window , which has been obscured through the loss of falling sonority diphthongs. By comparing plural formation to other morphophonological processes in Seenku, this paper argues that the plural suffix has been restructured as a featural suffix consisting of two features: the vocalic feature [+front], resulting in vowel fronting, and the tonal feature [+raised], resulting in tone raising. Given the atomic nature of the morphosyntactic feature plural, Seenku plural formation represents a strong case of multiple feature affixation, albeit a case that can be accounted for through Max constraints on feature values (Lombardi 2001, etc.) and Realize-Morpheme (van Oostendorp 2005; Trommer 2012) rather than the constraint Max-Flt argued for by Wolf (2007). A level-ordered approach retaining the vocalic suffix is also considered but is shown to suffer from a number of shortcomings, particularly with respect to tone and a challenging class of nasal stems. In short, this paper explores how the synchronic grammar copes with the vestiges of affixal morphology in a language that has undergone heavy reduction.  相似文献   

18.
Photosynthetic biochemical limitation parameters (i.e., Vcmax, Jmax and Jmax:Vcmax ratio) are sensitive to temperature and water availability, but whether these parameters in cold climate species at biome ecotones are positively or negatively influenced by projected changes in global temperature and water availability remains uncertain. Prior exploration of this question has largely involved greenhouse based short‐term manipulative studies with mixed results in terms of direction and magnitude of responses. To address this question in a more realistic context, we examined the effects of increased temperature and rainfall reduction on the biochemical limitations of photosynthesis using a long‐term chamber‐less manipulative experiment located in northern Minnesota, USA. Nine tree species from the boreal‐temperate ecotone were grown in natural neighborhoods under ambient and elevated (+3.4°C) growing season temperatures and ambient or reduced (≈40% of rainfall removed) summer rainfall. Apparent rubisco carboxylation and RuBP regeneration standardized to 25°C (Vcmax25°C and Jmax25°C, respectively) were estimated based on ACi curves measured in situ over three growing seasons. Our primary objective was to test whether species would downregulate Vcmax25°C and Jmax25°C in response to warming and reduced rainfall, with such responses expected to be greatest in species with the coldest and most humid native ranges, respectively. These hypotheses were not supported, as there were no overall main treatment effects on Vcmax25°C or Jmax25°C (p > .14). However, Jmax:Vcmax ratio decreased significantly with warming (p = .0178), whereas interactions between warming and rainfall reduction on the Jmax25°C to Vcmax25°C ratio were not significant. The insensitivity of photosynthetic parameters to warming contrasts with many prior studies done under larger temperature differentials and often fixed daytime temperatures. In sum, plants growing in relatively realistic conditions under naturally varying temperatures and soil moisture levels were remarkably insensitive in terms of their Jmax25°C and Vcmax25°C when grown at elevated temperatures, reduced rainfall, or both combined.  相似文献   

19.
Summary Cell recovery by means of continuous flotation of the Hansenula polymorpha cultivation medium without additives was investigated as a function of the cultivation conditions as well as of the flotation equipment construction and flotation operational parameters. The cell enrichment and separation is improved at high liquid residence times, high aeration rates, small bubble sizes, increasing height of the aerated column, and diameter of the foam column. Increasing cell age and cultivation with nitrogen limitation reduce the cell separation.Symbols CP cell mass concentration in medium g·l–1 - CR cell mass concentration in residue g·l–1 - CS cell mass concentration in foam liquid g·l–1 - V equilibrium foam volume cm3 - V gas flow rate through the aerated liquid column cm3·s–1 - VF feed rate to the flotation column ml/min - 1 V S/V foaminess s - mean liquid residence time in the column s  相似文献   

20.
The effect of the sinking rate, or rate of medium flow (φ) on the rate of phosphate incorporation (V) by the planktonic diatoms Thalassiosira fluviatilis Hust. and T. pseudonana Hasle & Heimdal in batch and chemostat cultures was determined by passing medium at defined flow rates (0.5–25.0 mm·min?1) over algae on membrane filters. At concentrations from 1 to 100 μg phosphorus·l?1 V, increases with increasing velocity of flow, approaching a maximum value (Vm) as described by the empirical relationship: where Kφ is the sinking rate value when V = 1/2 Vm+ Vo and Vo is the uptake at 0 rate of flow. By comparing uptake at controlled flow with uptake in a vigorously stirred medium, the phosphate concentration in the cell boundary layer can be determined. The sinking rate that reduces the phosphate concentration in the boundary layer to half of nominal concentration in the medium is much lower for the larger T. fluviatilis than for T. pseudonana. For both diatoms, it is inversely related to the nominal concentration.  相似文献   

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