A note on the structure of system state spaces and its implications on the existence of non-repeatable experiments

The implication of state space structure on the existence of a repeatable experimentE designed to determine if a states∈L has propertyP or notP is investigated. It is shown that if a state spaceL is connected, then no experimentE is repeatable. This formalism is used to demonstrate that if a propertyP has an associated set of points inL which is dense with dense complement inL, then there exists no repeatable experimentE which can be used to test whethers has propertyP or notP. Other consequences of this formalization are discussed.     

Hemibranchiate sphaeromatids (Crustacea: Isopoda) from Queensland, Australia, with a world-wide review of the genera discussed

All known Queensland species of the isopod family Sphaeromatidae, subfamily Sphaeromatinae (= hemibranchs), are discussed. The following new taxa are erected: Calcipila cornuta, gen. nov., sp. nov. ; Cymodoce tribullis, sp. nov. ; Cymodoce bipapilla, sp. nov. ; Paracilicaea aspera, sp. nov. ; Cilicaeopsis glebosa, sp. nov. ; Cilicaeopsis furculata, sp. nov. ; Cilicaea calcarifera, sp. nov. ; Zuzara curtispina, sp. nov. ; Zuzara digitata, sp. nov. ; and Clianella brucei, sp. nov. Exosphaeroma intermedium Baker is transferred to the genus Sphaeroma Latreille. The genus Dynoides Barnard is reviewed and its current synonymy is contested. With several new records, this brings the total number of sphaeromatid species known from Queensland to 49, 24 of which are in the subfamily Sphaeromatinae. A checklist of all sphaeromatid species occurring in Queensland waters is given. From the rest of Australia: Cymodoce tuberculata Haswell is given the replacement name Cymodoce haswelli, nom. nov. ; Cymodoce granulata Miers is made a junior synonym of Cerceis trispinosa (Haswell) (subfamily Dynameninae); Zuzara diadema Leach, Z. dicantha (Milne Edwards) and Z. Integra Haswell are made junior synonyms of Z. semipunctata Leach; Cilicaeopsis dakini Tattersall is tentatively transferred to the genus Paracilicaea Stebbing. The genera discussed are reviewed world-wide and among the non-Australian species: Exosphaeroma papillae Bayliff is transferred to the genus Sphaeroma; Sphaeroma irakiensis Ahmed is made a junior synonym of Sphaeroma annandalei annandalei Stebbing; Cymodoce richardsoniae Nobili is shown to be distinct from Cymodoce truncata Leach; Cymodoce eupyga Nobili is transferred to the genus Paracilicaea; Dynoides amblysinus Pillai, Dynoides castroi Loyola e Silva and Exosphaeroma globicaudum (Dana) are transferred to the genus Clianella Boone; Dynoides brasiliensis (Loyola e Silva; and Sphaeroma savignn Milne Edwards sensu Dana, 1853 are declared to be conspecific with Clianella castroi. The name Sorrentosphaera Verhoeff is made a junior synonym of Dynamene Leach (subfamily Dynameninae.     

The mathematical theory of group selection. I. Full solution of a nonlinear Levins E = E(x) model

The first complete overtime solution is obtained for a group selection model of Levins E = E(x) type with recolonization but no other gene flow between islands. Assuming a subdivided population at carrying capacity, the model describes selection at a biallelic locus (A, a) where a is opposed by Mendelian selection but is favored by a lower rate of extinction of demes having high a frequency. By contrast to the linear diffusion equations encountered in classical mathematical genetics, the PDE governing the dynamics is now nonlinear in the metapopulation gene frequency distribution φ(x, t); furthermore, the initial conditions now heavily influence the equilibrium distribution φ_∞(x). A fully explicit formula (20) expressing this dependence is derived. The results indicate that a fixation is never reached, but (A, a) polymorphism in the metapopulation will result if , where s 1 parametrizes the strength of Mendelian selection, E(x) is the Levins extinction operator, h (typically in the open interval (0, 1)) is the dominance of a, and B is a parameter measuring the flatness of the initial distribution f(x) in the x → 1 limit.     

Drift variances of FSTand GST statistics obtained from a finite number of isolated populations

Approximate formulas for the mean and variance of the F_STor G_ST statistic in a finite number of isolated populations are developed under the effect of random genetic drift. Computer simulation has shown that the approximate formulas give a fairly accurate result unless the initial frequency of one of the alleles involved is close to 1 and t/2N is large, where N is the effective size of a subpopulation and t is the number of generations. It is shown that when the number of subpopulations (s) is small, the mean of F_STor G_ST depends on the initial gene frequencies as well as on s. When the initial frequencies of all alleles are nearly equal to each other and the number of subpopulations is large, the distribution of F_ST in the early generations is bell-shaped. In this case Lewontin and Krakauer's k parameter is approximately 2 or less. However, if one of the initial allele frequencies is close to 1, the distribution is skewed and leptokurtic, and the k parameter often becomes larger than 2 in later generations. Thus, even under pure random genetic drift, Lewontin and Krakauer's test of selective neutrality of polymorphic genes in terms of F_ST is not always valid. It is also shown that Jacquard's approximate formula for k generally gives an overestimate.     

Convergence to Normality of the Asymptotic Quasi‐Score Function on a Linear Model

The asymptotic quasi‐likelihood method is considered for the model y_t = f_t(θ) + M_t, t = 0,1, …,T where f_tθ) is a linear predictable process of the parameter of interest θ, M_t is a martingale difference, and the nature of E(M_t² | ℱ_t–1) is unknown. This paper is concerned with the limiting distribution of the asymptotic quasi‐score function of such a model. Confidence intervals and hypothesis testing of θ is derived from the limiting distribution. Comparison is made between the estimates obtained through this method and those obtained through the least squares method.     

Echidnopsis thulinii sp. nov. (Apocynaceae–Asclepiadoideae) with a review of the infrageneric classification of the genus

Echidnopsis thulinii M. G. Gilbert is described from northern Somalia. The infrageneric classification of Echidnopsis Hook. f. is reviewed in the light of recently published molecular phylogenies. The new species belongs to E. sect. Echidnopsis and a key to the species of this section is provided. A lectotype, supported by an epitype, is designated for E. virchowii K. Schum. Echidnopsis sect. Profundicoronata Bruyns is included within sect. Vadosicoronata Bruyns and two new sections recognised: E. sect. Pseudopectinaria (Lavranos) M. G. Gilbert, based on the genus Pseudopectinaria Lavranos, and E. sect. Sobolifera M. G. Gilbert. A key is given to the sections of Echidnopsis.     

Rediscovery of Ardisia gigantifolia and the reinstatement of A. kteniophylla (Primulaceae) – finding the correct name for the Chinese medicinal plant ’Zou Ma Tai’

With the rediscovery of Ardisia gigantifolia, the long‐standing confusion with A. pseudoverticillata, A. kteniophylla and A. dasyrhizomatica owing to the misinterpretation of the type of A. gigantifolia is clarified. It is shown that A. dasyrhizomatica is a later synonym of A. gigantifolia, while A. kteniophylla and A. pseudoverticillata are conspecific and represent another species for which A. kteniophylla is the earliest name available. Ardisia kteniophylla is the correct scientific name for the Chinese medicinal plant ’Zou Ma Tai’.     

Hieraciumpallidum subsp. aetnense (Asteraceae), a new subspecies from Sicily (Italy), with notes on the taxonomy of H. pallidum Biv.

Hieracium pallidum subsp. aetnense Gottschl., Raimondo & Di Grist. is described and illustrated. H.pallidum is considered as an intermediate species between H. schmidtii and H. racemosum (“schmidtii>racemosum”) and is placed in H. sect. Grovesiana. By consequence, H.lanudae Gottschl. is transferred to H. pallidum as H. pallidum subsp. lanudae (Gottschl.) Gottschl., Raimondo & Di Grist. A key for the three recognised subspecies of H. pallidum is provided.     

A revision of the moss genus Sciaromium (Mitt.) Mitt. I. General remarks and the section Aloma Dusén

Abstract

The generic name Sciaromium (Mitt.) Mitt. that was originally used as a sectional epithet in Leskea is synonymous with Echinodium Jul E. madeirense Jur. [= E. spinosum (Mitt.) Jur.] is selected as the lectotype of the genus Echinodium. A historical review of taxonomic and nomenclatural problems in Sciaromium is provided and taxa that had previously been excluded from this genus are briefly discussed. Sciaromium flavidulum Dusén is a Eurhynchium and the combination E. flavidulum (Dusén) Ochyra is made. Sciaromium sect. Aloma Dusén is synonymous with Eurhynchium since E. flavidulum serves as the type species of this section. The taxonomic position of S. gracile Dusén is discussed and this species is considered synonymous with Amblystegium chilense Lor., which is transferred to Pseudoleskea and the appropriate new combination P. chilensis (Lor.) Ochyra made. Type specimens of S. bellii Broth., S. elimbatum Broth. & Watts and S. forsythii Broth. in Broth. & Watts are briefly described and illustrated; these species are reduced to synonymy with the polymorphic Cratoneuropsis relaxa (Hook. f. & Wils.) Fleisch. in Broth.     

Systematic revision of the catfish genusSilurus,with description of a new species from Thailand and Burma

On the basis of external morphology and anatomy, 17 scpeies of the genusSilurus Linnaeus including a new species,S. torrentis from Thailand and Burma, are recognized as valid.S. bedfordi Regan is synonymized withS. asotus, andS. goae Haig is transferred to the genusOmpok. From an anatomical study of 12 species, the diagnostic feature of the genusParasilurus Bleeker is revealed to be invalid, and the genus is synonymized withSilurus. From the phylogenetic analysis, the genusSilurus is divided into two major species groups, thecochinchinensis group which is disributed mainly in Southeast Asia, and theglanis group which is further separated into three subgroups occurring separately in East Asia and Europe. The pattern of distribution and relationships between ontogeny and phytogeny in the genusSilurus are briefly discussed.     

Notes on the little known moss Fissidens firmus Mitt. (Fissidentaceae)

Abstract

Fissidens firmus is revised, described, illustrated and a distribution is provided. It is compared to Fissidens hollianus, Fissidens pseudofirmus, Fissidens sedgwickii and Fissidens touwii. It is provisionally distinguished from F. firmus sensu auct. Fissidens multiflorus is reduced to F. hollianus. Lectotypes are designated for Fissidens multiflorus and Fissidens giesenhagenii. The collection that was reported from India as F. firmus appears to be F. hollianus. Thus, the present Western Ghats collection is effectively the first Indian record of F. firmus.     

Genetics of black gram (Phaseoulus mungo L.)

In black gram, the mode of inheritance of six pairs of characters has been analysed, viz.: erect versus spreading habit; hairy versus glabrous fruit; bluish black versus straw fruit colour; shiny versus dull seed surface; green versus brown seed colour. On the basis of the results, the following gene symbols are proposed:Erect habitSp is incompletely dominant over spreading,sp.—Hairy fruitG is dominant over glabrous,g, while inG plants the extent of hairiness is controlled by more than one pair of genes.—Bluish black fruit colourS is dominant over straw,s.—Shiny seed surfaceD is dominant over dull,d.—Green seed colourBr is dominant over brown;br.—Mosaic colour pattern of the seedUc is dominant over non-patterned,uc.Linkage was observed betweenS andUc, as well as betweenBr andD.     

A review of the Tandanicolinae (=Monodhelminthinae) (Digenea: Fellodistomidae), with a description of Prosogonarium angelae n. sp.

The Tandanicolinae is reviewed, redefined and considered a subfamily of the Fellodistomidae. The Monodhelminthinae Dollfus, 1937, Mehratrematinae Srivastava, 1939, Prosogonariinae Mehra, 1963 and Buckleytrematinae Yamaguti, 1971 are synonyms of the Tandanicolinae. Genera included in the Tandanicolinae are Tandanicola, Monodhelmis, Buckleytrema and Prosogonarium. Burnellus and Mehratrema are made new synonyms of Monodhelmis. The composition of each genus is reviewed. Monodhelmis arii Yamaguti, 1952, Mehratrema arii Gu & Shen, 1979, Mehratrema dollfusi Srivastava, 1939, Monodhelmis philippinensis Velasquez, 1961, Mehratrema polynemusinis Chauhan, 1943 and Mehratrema skrjabini Karyakarte, 1969 are considered synonyms of Monodhelmis torpedinis. Monodhelmis elongatus Bilqees, 1970 is considered a species inquirenda. Prosogonarium angelae n. sp. is described from Euristhmus lepturus from Moreton Bay, Queensland. It is distinguished by the number and distribution of the vitelline follicles and the extent of the caeca. New records are given for Monodhelmis torpedinis from Arius graeffei and E. lepturus, M. trichofurcata from Tandanus tandanus, and Buckleytrema indica from A. graeffei, all from southern Queensland. Buckleytrema indica is redescribed and B. postacetabulorchis is synonymised with that species. Relationships within the Tandanicolinae were considered by cladistic analysis.     

Helix-coiled transition in heteropolymers. I. Ground-state energy

A new technique is presented for treating the ground state of an heteropolymer with a random sequence of components. An exact system of equations is found for determining the ground state energy E which is equal to the polymer free energy f in the lowest-order approximation in T/V (V/2 is the large “surface” energy arising at the boundaries between coiled and “helical” sections: V ? T, U_k; U₁ and –U₂ are the free energies of the components counted from the corresponding coiled state energies). These equations are essentially simplified at certain fixed values of the ratio U₁/U₂. For integer values of U₂/U₁ and U₁/U₂ a solution is obtained with an accuracy exp(–V/U_k). The ground-state energy as a function of U₁ and U₂ is shown to be highly irregular: its derivatives have jumps at an infinite number of points. These jumps provide a fine structure of the melting curves. A smoothed over the jumps function E′ is found by way of analytic continuation from the integer values of U₁/U₂ and U₂/U₁. The accuracy of the approximation f ≈ E is estimated and the correctional term of order T/V is determined.     

Approximate Michaelis-Menten kinetics displayed in a stochastic model of cell-mediated cytotoxicity

A nonlinear continuous-time Markov chain describing a two-step process of cytolytic cells binding to target and the subsequent lysis and release of label is shown to have kinetics which resemble standard enzyme-substrate kinetics. The Michaelis-Menten saturation function is found as a special case resulting when the target population is in excess. A comparison theorem for the pseudo-steady-state distribution Π is constructed to enable examination of that distribution whose expected value E and variance V satisfy - K_mE + (C_T − E)(T_T − E) + V = 0, where K_m is the Michaelis half-saturation constant and C_T and T_T are the initial populations of the two cell types. Using Π as an initial condition, the release of label process is examined. The main result is that the fraction of specific release, ƒ, has the approximate form when T_t is large, so that a nonlinear regression procedure is appropriate for the determination of the parameters.     

Genetic interactions between FLM and other flowering-time genes in Arabidopsis thaliana

FLOWERING LOCUS M (FLM) is a MADS-domain gene that acts as an inhibitor of flowering in Arabidopsis. Here we describe the genetic interaction of FLM with genes in the photoperiod and autonomous flowering pathways. Although the sequence of FLM is most similar to that of FLC, FLM and FLC interact with different flowering pathways. It has been previously shown that flc lesions suppress the late-flowering phenotype of FRI-containing lines and autonomous-pathway mutants. However, flm lesions suppress the late-flowering phenotype of photoperiod-pathway mutants but not that of FRI-containing lines or autonomous-pathway mutants. Another MADS-domain flowering repressor with a mutant phenotype similar to FLM is SVP. The late-flowering phenotype of FLM over-expression is suppressed by the svp mutation, and an svp flm double mutant behaves like the single mutants. Thus FLM and SVP are in the same flowering pathway which interacts with the photoperiod pathway. Abbreviations: CO, CONSTANS; FLC, FLOWERING LOCUS C; FLM, FLOWERING LOCUS M; FRI, FRIGIDA; GI, GIGANTEA; LD, LUMINIDEPENDENS; SVP, SHORT VEGETATIVE PHASE; FCA is not an abbreviation