Tail Shape Research Articles

Phasmarhabditis kenyaensis n. sp. (Nematoda: Rhabditidae) from the slug, Polytoxon robustum, in Kenya

Summary A new species of Phasmarhabditis was isolated from the slug, Polytoxon robustum, from Nairobi, Kenya. The nematode was identified using morphological, morphometric, molecular and phylogenetic analyses. Phasmarhabditis kenyaensis n. sp. is characterised by an infective juvenile with the longest body length in the genus, measuring 1232 (1107-1336) μm, by the presence of males with a bursa bearing nine bilateral pairs of genital bursal papillae and one pair of papilliform phasmids flanking the tail, cephalate paired spicules, with an arc length of 71 (57-81) μm, as well as by females with a vulva located at the mid-body region and a conoid tail shape, with two phasmids located at ca 40% of the tail length. The molecular phylogeny of the new species, as inferred from its SSU (small subunit) rRNA gene, places P. kenyaensis n. sp. genetically close to undescribed phasmarhabditids from South Africa, suggesting an African grouping, while the D2-D3 (large ribosomal subunit) and ITS region analyses relate P. kenyaensis n. sp. to P. meridionalis, with weak bootstrap support. This is the third new Phasmarhabditis species described from the African continent, the new species bringing the total known complement of the genus to 14 species. A morphometric compendium to all species cultured in vivo is supplied.

Pengaruh Panjang Batang dan Bentuk Daun Ekor pada Turbin Angin Sumbu Horizontal dengan Mekanisme Furling terhadap Performa Turbin

Small-scale wind turbines that operate at low wind speeds regularly will face yawing performance problems. The purpose of this study was to determine the effect of stem length and tail shape on turbine performance through the power generated and the yawing angle and furling angle that formed. An experimental method was used in this research. Tail stem length variations that used were 0.35 m, 0.53 m and 0.71 m. The tail shape varies Rectangular, Trapezoidal, Triangular, Up Rectangular, Down Rectangular, Up Trapezoidal, Down Trapezoidal, Up Triangular and Down Triangular. Wind speed used in this case is 4.3 m/s, 4.8 m/s and 5.2 m/s. The tests carried out at Marina Beach, Semarang. Power measurements using a digital multimeter. Yawing and furling angle measurements using video recordings and measured using Solidworks. Wind speed measurements using a digital anemometer. The results showed that the best configuration is the triangular tail shape with 0,53 m of tail stem length. The power generated of this configuration has increased from wind speed of 4.3 m/s (0.816 Watt) to 4.8 m/s (1.140 Watt) and decreased at a wind speed of 5.2 m/s (1.081 Watt). This phenomenon is related to the design where at wind speed above 5 m/s, the design of furling mechanism will work to reduce the capture of wind energy by diverting the direction of the rotor towards the wind direction. So that the damage of the blade due to higher wind pressure can be minimized.

Restructuring of a meiobenthic assemblage after sediment contamination with an antibacterial compound: Case study of ciprofloxacin

A microcosm experiment was conducted to evaluate the impacts of the fluoroquinolone antibiotic ciprofloxacin on meiobenthic taxa abundance, nematode genus structure, and functional trait parameters. Sediment samples were experimentally enriched with four different doses of ciprofloxacin [D1 (50 ppm Dry weight ‘DW’), D2 (100 ppm DW), D3 (200 ppm DW), and D4 (500 ppm DW)] and were then compared with non-enriched sediments (controls). After one month of exposure, the data showed that ciprofloxacin had altered the meiofaunal taxa abundance. A change in the structure of nematofaunal genera was observed, particularly with the highest dose (D4), which was characterized by the lowest taxonomic diversity. The SIMPER analysis revealed that the average dissimilarity between nematode communities increased with increasing doses of ciprofloxacin. Two dimensional (2D) non-metric multidimensional scaling (nMDS) plots and relative abundances of functional groups of nematode genus assemblages revealed that all functional trait abundances were affected, particularly with the highest dose. However, only the amphid shape and feeding group functions showed a clear distribution separation between the control and ciprofloxacin treatments. The nMDS second-stage ordination of inter-matrix rank correlations for matrices including genus and functional traits showed that the tail shape was the closest functional trait to the generic distribution. Thus, only the curves of cumulative dominance related to the tail shape mirrored discernibly the sedimentary concentrations in ciprofloxacin.

Causal Inference Machine Learning Leads Original Experimental Discovery in CdSe/CdS Core/Shell Nanoparticles.

The synthesis of CdSe/CdS core/shell nanoparticles was revisited with the help of a causal inference machine learning framework. The tadpole morphology with 1-2 tails was experimentally discovered. The causal inference model revealed the causality between the oleic acid (OA), octadecylphosphonic acid (ODPA) ligands, and the detailed tail shape of the tadpole morphology. Further, with the identified causality, a neural network was provided to predict and directly lead to the original experimental discovery of new tadpole-shaped structures. An entropy-driven nucleation theory was developed to understand both the ligand and temperature dependent experimental data and the causal inference from the machine learning framework. This work provided a vivid example of how the artificial intelligence technology, including machine learning, could benefit the materials science research for the discovery.

Estimating expected shortfall using a quantile function model

AbstractDistribution of financial returns defined by the existing GARCH models usually focus on the overall features such as the location, scale, skewness and kurtosis of the distribution. When using such GARCH models for expected shortfall (ES) estimation, it is difficult to consider specific information about the tails (such as the shape of the tails of the distribution), resulting in possible bias in ES estimation. We propose a quantile function threshold GARCH model to overcome some of the limitations of existing models. The model allows us to use the information including the skewness and tail shape of the distribution and the structure changes in the volatility of financial returns to obtain ES estimates. Our results show that the proposed model outperforms the benchmark models, confirming that tail shape of the distribution also plays an important role in ES estimation.

Morphological and molecular characterisation of three known species of Criconematoidea from Iran

Summary In this study, we provide morphological and molecular characterisation of three known species of the Criconematoidea, namely Criconema cylindraceum, Paratylenchus alleni and P. steineri, recovered from Iran. Descriptions, morphometric data, drawings and photomicrographs are provided, and comparisons are made with closely related species. Phylogenetic analysis using the D2-D3 expansion segments of the 28S rRNA gene revealed that C. cylindraceum formed a cluster with Ogma decalineatus, a species with a similar head structure, but with differences in cuticle ornamentation, tail shape and morphometric characters. Moreover, P. alleni grouped with species of Paratylenchus having four lateral lines and a short stylet (< 40 μm), exceptionally including the unresolved P. straeleni, while P. steineri formed a clade with long stylet species, including P. teres and P. wuae. The taxonomic placement of C. cylindraceum in Criconema, rather than in Criconemoides, is justified, and P. teres is molecularly differentiated from P. steineri, the two species differing in having or lacking a stylet in the fourth-stage juvenile.

Evaluating CMIP6 model fidelity at simulating non-Gaussian temperature distribution tails

Under global warming, changes in extreme temperatures will manifest in more complex ways in locations where temperature distribution tails deviate from Gaussian. Confidence in global climate model (GCM) projections of temperature extremes and associated impacts therefore relies on the realism of simulated temperature distribution tail behavior under current climate conditions. This study evaluates the ability of the latest state-of-the-art ensemble of GCMs from the Coupled Model Intercomparison Project phase six (CMIP6), to capture historical global surface temperature distribution tail shape in hemispheric winter and summer seasons. Comparisons with a global reanalysis product reveal strong agreement on coherent spatial patterns of longer- and shorter-than-Gaussian tails for both sides of the temperature distribution, suggesting that CMIP6 GCMs are broadly capturing tail behavior for plausible physical and dynamical reasons. On a global scale, most GCMs are reasonably skilled at capturing historical tail shape, exhibiting high pattern correlations with reanalysis and low values of normalized centered root mean square difference, with multi-model mean values generally outperforming individual GCMs in these metrics. A division of the domain into sub-regions containing robust shift ratio patterns indicates higher performance over Australia and an overestimation of the degree to which tails deviate from Gaussian over southeastern Asia in all cases, whereas model skill over other regions varies depending on season and tail of the temperature distribution. For example, model performance during boreal winter indicates robust agreement (>85% models) with reanalysis for shorter-than-Gaussian warm tails over the Northern Hemisphere, whereas cold-tail shape is generally mischaracterized by GCMs over western Russia. Although there is spatial and model variability, overall, results highlight the capability of the CMIP6 ensemble in capturing seasonal temperature distribution deviations from Gaussianity, boosting confidence in model utility and providing insight into the complexity of future changes in temperature extremes.

An integrative taxonomic study of the needle nematode complex Longidorus goodeyi Hooper, 1961 (Nematoda: Longidoridae) with description of a new species.

Needle nematodes are polyphagous root-ectoparasites parasitizing a wide range of economically important plants not only by directly feeding on root cells, but also by transmitting nepoviruses. This study deciphers the diversity of the complex Longidorus goodeyi through integrative diagnosis method, based on a combination of morphological, morphometrical, multivariate analysis and molecular data. A new Longidorus species, Longidorus panderaltum n. sp. is described and illustrated from a population associated with the rhizosphere of asphodel (Asphodelus ramosus L.) in southern Spain. Morphologically, L. panderaltum n. sp. is characterized by having a moderately long female body (5.2-7.0 mm), lip region bluntly rounded and slightly offset by a depression with body contour, amphidial pouch with slightly asymmetrical lobes, odontostyle 80.5–101.0 µm long, tail short and conoid rounded. Longidorus panderaltum n. sp. is quite similar to L. goodeyi and L. onubensis in major morphometrics and morphology. However, differential morphology in the tail shape of first-stage juvenile, phylogeny and haplonet analyses indicate they are three distinct valid species. This study defines those three species as members of L. goodeyi complex group and reveals the taxonomical complexity of the genus Longidorus. This L. goodeyi complex group demonstrated that the biodiversity of Longidorus in this region is still not fully clarified.

Systematic position of the genus Atetylenchus Khan, 1973 (Nematoda: Tylenchidae) with description of two new species

Summary Two new and one known species of Atetylenchus recovered from Dezful, Khuzestan Province, south-western Iran, are illustrated and described using morphological, morphometric and molecular data. Atetylenchus dezfuliensis n. sp. is characterised by medium-sized body 700-998 μm long, stylet 10.0-11.5 μm long, characteristic tail shape, first tapering regularly but then cylindrical to slightly clavate and 90-136 μm long, phasmids located at one-third anterior part of tail and short spicules 18.7 μm long. Atetylenchus longilabiatus n. sp. is characterised by small-sized body 593-720 μm long, prominent lip region, stylet 9.5-12.5 μm long, conical tail with hook-shaped terminus and 42-63 μm long, phasmids located near mid-tail and short spicules 17.5 μm long. Atetylenchus cf. graminus is characterised by small-sized body 643-787 μm long, stylet 10.7-11.7 μm long, vulva located at 51.7-55.1% of the body length, and conical tail with finely rounded end and 63-69 μm long. Molecular data are provided for the characterisation of this genus from these two new and one known species using ribosomal genes (18S and 28S rRNA). This genus is molecularly separated from Psilenchus, but closely related in both genes. These molecular markers showed different phylogenies for both genera; partial 18S showed their relationship with Tylenchidae, while 28S rRNA showed their relationship with Merliniidae. A key to the genus is provided for species identification.

Species diversity of ring nematodes of the genus Criconemoides (Nematoda: Criconematidae) based on three new species from China, using integrative taxonomy

Ring nematodes of the genus Criconemoides are a group of polyphagous, migratory root-ectoparasites of plants. In a nematological survey of Zhejiang Province, three new Criconemoides species were isolated from the rhizosphere of Citrus sp., Euonymus alatus and Pterocarya stenoptera trees. In the present study, the new species characterized using an integrative taxonomic approach and described as Criconemoides parainformis n. sp., C. geraerti n. sp. and C. rotundicaudatus n. sp. Three of the species shares truncated anteriorly flattened lip region comprised of two annuli, body annuli margin smooth with few anastomoses, (except C. rotundicaudatus n. sp. it has crenated annuli margins and numerous anastomoses), excretory pore 1–2 annuli posterior to pharyngeal bulb base, (except C. geraerti n. sp. it has excretory pore at the same level, or 1–2 annuli anterior to pharyngeal bulb base), vulva closed, anus hardly visible 1–3 annuli posterior to vulva. The new species can be distinguished based on their en face view pattern under scanning electron microscope (SEM) and the tail shapes. i.e. C. parainformis n. sp. has an ellipsoid oral disc, slightly fused pseudolips and tail ending in a bilobed terminus. C. geraerti n. sp. has a hexagonal oral disc, separated pseudolips, and a bluntly conoid tail. C. rotundicaudatus n. sp. has a rounded oral disc, well developed pseudolips, and a short broadly rounded tail. Besides detailed morphological studies using SEM, genomic and mitochondrial molecular data were obtained for the three described new species. In inferred phylogenies, these three species clustered with known Criconemoides species in 18S, 28S, ITS and coxI trees. Currently, only four known Criconemoides species occur in China and the discovery of the three new Criconemoides species in present study has increased our knowledge on the diversity of Criconemoides in China.

Assessment of return value estimates from stationary and non-stationary extreme value models

This article compares the accuracy of return value estimates from stationary and non-stationary extreme value models when the data exhibits covariate dependence. The non-stationary covariate representation used is a penalised piecewise-constant (PPC) model, in which the data are partitioned into bins defined by covariates and the extreme value distribution is assumed to be homogeneous within each bin. A generalised Pareto model is assumed, where the scale parameter can vary between bins but is penalised for the variance across bins, and the shape parameter is assumed constant over all covariate bins. The number and sizes of covariate bins must be defined by the user based on physical considerations. Numerical simulations are conducted to compare the performance of stationary and non-stationary models for various case studies, in terms of quality of estimation of the T-year return value over the full covariate domain. It is shown that a non-stationary model can give improved estimates of return values, provided that model assumptions are consistent with the data. When the data exhibits non-stationarity in the generalised Pareto tail shape, the use of non-stationary model assuming a constant shape parameter can produce biases in return values. In such cases, a stationary model can give a more accurate estimate of return value over the full covariate domain as only the most extreme observations (regardless of covariate) are used to estimate tail shape. In other cases, the assumption of a stationary model will ignore key features of the data and be less reliable than a non-stationary model. For example, if a relatively benign covariate interval exhibits a long (or heavy) tail, extreme values from this interval may influence the T-year return value for very large T. However the sample of peaks over threshold, with high threshold, used to estimate a stationary model in this case may not include sufficient observations from this interval to estimate the return value adequately.

Pure premium calculation of rice farm insurance scheme in Indonesia based on the 4-parameter beta mixture distribution

The Indonesian Government introduced rice farm insurance scheme (Asuransi Usaha Tani Padi – AUTP program) to protect rice farm from loss caused by flood, drought and pest and disease infestations. It has been discussed the method to calculate pure premium of the rice farm insurance scheme in Indonesia with assume that the distribution of rice yield data is normal distribution, gamma distribution, or normal mixture distribution. The normal distribution can be used for the case of distribution of rice yield data in the form of symmetry. The gamma distribution can be used for the case of distribution of rice yield data in the form of skewed to the right or positively skewed. In addition, the normal and gamma distributions are categorized as unimodal distributions. It has also been discussed the method of calculating pure premium of the rice farm insurance scheme in Indonesia with the assumption that the rice yield data is normal mixture distribution. The normal mixture distribution can be categorized as multimodal distribution. Characteristic of the normal mixture distribution is suitable for rice yield data in Indonesia that contain rice yield data from several provinces. On the other hand, it is also known that the 4-parameter beta mixture distribution can be applied to rice yield data in Indonesia. This distribution is more flexible than the normal mixture distribution in terms of the tail shape of the distribution. In this paper, pure premium calculation method of the AUTP program is formulated with assume that the distribution of rice yield data is the 4-parameter beta mixture distribution. Monte Carlo simulation is used to evaluate performance of the method. The method is applied to the rice productivity data in several provinces in Indonesia for the period 1970 to 2016.

Morphological and molecular characterization of potato cyst nematode populations from The Nilgiris

Quarantine species of potato cyst nematodes (PCN), Globodera rostochiensis and G. pallida, were reported from Nilgiris during 1961. The studies were carried out at ICAR-CPRS, Muthorai, Ooty and ICAR-CPRI, Shimla during 2015–17. To investigate the distribution of PCN, soil samples were collected from potato growing areas of Nilgiris and were identified based on morphological criteria and ITS-1 region. Molecular characterization using ITS-1 region specific primers revealed the presence of pure population of G. rostochiensis in 50% of the samples, G. pallida in 10.7% of the samples, mixed population in 28.6% of the samples and absence of both the species in 10.7% of the samples. The phylogenetic analysis inferred by the sequence of the ITS-1 region confirmed 92–100% genetic similarities in Globodera spp. Seventeen isolates of G. rostochiensis showed 92–99% genetic similarity and rest four 92–100% similarities. Whereas, genetic similarity among the ten isolates of G. pallida was 96.1–99.4%. In the morphometric characters J2s of G. rostochiensis exhibited shorter body length (459.8 μm) than G. pallida (493.7 μm). G. rostochiensis and G. pallida had difference in mean stylet length (21.1 μm and 23.4 μm respectively), hyaline tail terminal length (28.3 μm and 24.2 μm respectively) and shape of stylet knob. Highest mean value of vulval basin-anus distance (65.3 μm), number of cuticular ridges between vulval basin-anus (18.4) and Granek’s ratio (4.0 μm) was recorded in G. rostochiensis than G. pallida. Therefore, the present study will help to take appropriate and region specific PCN management decisions according to species dominance in that area.

English

Updated result of the phenotypic characterization and description of the indigenous sheep population was reviewed. The reviewed paper used reporting and tabulating published descriptive phenotypic information on Ethiopian breeds with the aim of dissemination of relevant information for the beneficiaries. The original sheep breed types in Ethiopia that migrated from South West Asia to Africa and then to Ethiopia were the thin-tailed, fat-tailed and fat-rump. Through time, they evolved into 14 traditionally recognized sheep breeds which are identified and described through phenotypic characterization of the representative sample flocks. The breeds adapted to different agro ecological zones varied in topographical features and humidity. The overall reviews of the adult average live body weight variation of the local sheep population of Ethiopia are classified into 20 to 25 kg (Elle, Abergelle and Menz); 26 to 30 kg (Afar, Tikur, Highland sheep, Washera and Black Head Somali [BHS]); 31 to 35 kg (Bonga, Begait, Horro, Arusi-Bale and Farta) and 36 to 40 kg (Gumuz). The large sheep breeds of Ethiopia are Begait, Washera, Gumuz, Horro and Bonga. There is a variation on phenotypic performance among the sheep breeds of the Ethiopia in terms of body shape and size, ear profile and size, head profile, tail size and shape, coat color and on the adaptive behaviors. Molecular characterization should be done for comprehensive genetic evaluation and classification of the indigenous sheep population at national level.   Key words: Sheep breed, phenotypic variation, sheep classification, tail type and tail shape.

Three-dimensional tomographic study of dermal armour from the tail of the Triassic aetosaur Stagonolepis robertsoni

The aetosaur Stagonolepis robertsoni was the first reptile to be named from the Late Triassic Lossiemouth Sandstone Formation of Morayshire. Its characteristic rectangular armour plates have been reported in isolation and in association with skeletal remains. Here we present for the first time a three-dimensional reconstruction of the armour plates around the tail in association with caudal vertebrae and a chevron, to give direct evidence of the body outline. The caudal vertebral column was surrounded by eight bony osteoderms, paired paramedian dorsal and ventral plates, and a pair of lateral osteoderms on right and left. The tail shape was subcircular, broader than high. The osteoderms overlap like roofing tiles, the posterior margin of each overlapping the osteoderm following behind. The success of these scans suggests that computed tomography scanning could reveal excellent detail of all the Elgin reptiles in the future. Supplementary material : Three-dimensional models of the two fossil specimens are available at: https://doi.org/10.6084/m9.figshare.c.4824183

Quasi-diffusion magnetic resonance imaging (QDI): A fast, high b-value diffusion imaging technique

To enable application of non-Gaussian diffusion magnetic resonance imaging (dMRI) techniques in large-scale clinical trials and facilitate translation to clinical practice there is a requirement for fast, high contrast, techniques that are sensitive to changes in tissue structure which provide diagnostic signatures at the early stages of disease. Here we describe a new way to compress the acquisition of multi-shell b-value diffusion data, Quasi-Diffusion MRI (QDI), which provides a probe of subvoxel tissue complexity using short acquisition times (1–4 ​min). We also describe a coherent framework for multi-directional diffusion gradient acquisition and data processing that allows computation of rotationally invariant quasi-diffusion tensor imaging (QDTI) maps.QDI is a quantitative technique that is based on a special case of the Continuous Time Random Walk model of diffusion dynamics and assumes the presence of non-Gaussian diffusion properties within tissue microstructure. QDI parameterises the diffusion signal attenuation according to the rate of decay (i.e. diffusion coefficient, D in mm2 s−1) and the shape of the power law tail (i.e. the fractional exponent, α). QDI provides analogous tissue contrast to Diffusional Kurtosis Imaging (DKI) by calculation of normalised entropy of the parameterised diffusion signal decay curve, Hn, but does so without the limitations of a maximum b-value.We show that QDI generates images with superior tissue contrast to conventional diffusion imaging within clinically acceptable acquisition times of between 84 and 228 ​s. We show that QDI provides clinically meaningful images in cerebral small vessel disease and brain tumour case studies. Our initial findings suggest that QDI may be added to routine conventional dMRI acquisitions allowing simple application in clinical trials and translation to the clinical arena.

Rates of ecomorphological trait evolution in passerine bird clades are independent of age

Abstract Although the links between species richness and diversification rates with clade age have been studied extensively, few studies have investigated the relationship between the rates of trait evolution and clade age. The rate of morphological trait evolution has repeatedly been shown to vary through time, as expected, for example, for adaptive radiations, but the strength and sources of this variation are not well understood. We compare the relationship between the rates of trait evolution and clade age across eight monophyletic clades of passerine birds by investigating ecomorphological traits, i.e. morphological traits that influence the ecology of the species directly. We study the ecomorphological divergence pattern using analyses of the disparity through time and determine the best-fitting model of evolution for each trait in each clade. We find no support for a consistent dependence of evolutionary rates on clade age across wing, tail, tarsus and beak shape in our eight clades and also show that early burst models of trait evolution are rarely the best-fitting models within these clades. These results suggest that key innovations or adaptive radiations might be less common evolutionary patterns and processes than generally thought or might depend on the taxonomic level investigated.

The effects of hydroperiod and predator density on growth, development, and morphology of wood frogs (Rana sylvatica)

Accelerated development and metamorphosis allow tadpoles to escape death by leaving the aquatic habitat before it dries. Phenotypic plasticity in response to predators typically includes development of physical and behavioral traits, including changes in tail coloration, activity rate, and tail shape and body size. Responding to predators increases the probability of survival, but lowers growth rate. Responses to two common stressors in ephemeral aquatic habitats appear to be in direct opposition to one another. In this study, we examined the individual and interactive effects of hydroperiod and predator density on the life history, morphology, and metamorphosis of wood frog (Rana sylvatica) tadpoles in an outdoor mesocosm study. Tadpoles were exposed to three hydroperiods (constant, intermediate, and short) and three predator densities (zero, four, and eight Anax junius naiads) using a complete block design. The threat of habitat desiccation resulted in increased developmental rate and shorter larval periods. Increased predator densities resulted in increased size at metamorphosis and development of the induced morphology. Although the threat of predation precluded growth and developmental responses to shortened hydroperiod in tadpoles, it did not negate the metamorphic responses to hydroperiod. It appears that, at least at the treatment levels imposed in this experiment, the interaction between these multiple stressors is complex, with the stressors acting both individually and together on different aspects of tadpole ecology.

Verification and Analysis of Sheep Tail Type-Associated PDGF-D Gene Polymorphisms.

Simple SummaryPDGF-D can be considered a candidate gene for selection for sheep tail type. This study investigated genetic variation of the PDGF-D gene in sheep with different tail types verified at a cellular level and revealed the molecular mechanism of PDGF-D in sheep tail fat deposition. We detected a total of two SNPs among 533 sheep. g.4122606 C > G site was significantly correlated with tail length, and g.3852134 C > T site was significantly correlated with tail width. In addition, overexpression of PDGF-D in sheep preadipocytes can promote adipogenic differentiation. The PDGF-D gene may participate in sheep tail fat deposition and could be used for molecular marker-assisted selection of sheep tail type.The aim of this study was to examine the correlation between the platelet-derived growth factor-D (PDGF-D) gene and sheep tail type character and explore the potential underlying mechanism. A total of 533 sheep were included in this study. Polymorphic sites were examined by Pool-seq, and individual genotype identification and correlation analysis between tail type data were conducted using the matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF-MS) method. JASPART website was used to predict transcription factor binding sites in the promoter region with and without PDGF-D gene mutation. The effect of PDGF-D on adipogenic differentiation of sheep preadipocytes was investigated. Two single nucleotide polymorphism sites were identified: g.4122606 C > G site was significantly correlated with tail length, and g.3852134 C > T site was significantly correlated with tail width. g.3852134 C > T was located in the promoter region. Six transcription factor binding sites were eliminated after promoter mutation, and three new transcription factor binding sites appeared. Expression levels of peroxisome proliferator-activated receptor gamma (PPARγ) and lipoproteinlipase (LPL) were significantly up-regulated upon PDGF-D overexpression. Oil red O staining showed increased small and large oil drops in the PDGF-D overexpression group. Together these results indicate the PDGF-D gene is an important gene controlling sheep tail shape and regulating sheep tail fat deposition to a certain degree.

Two New Marine Free-Living Nematodes from Jeju Island Together with a Review of the Genus Gammanema Cobb 1920 (Nematoda, Chromadorida, Selachinematidae)

In the context of exploration of meiofauna in a sandy intertidal zone of Jeju Island (South Korea), over 70 nematode species are identified, some which have been proven to be new for science. Two new free-living marine nematode species of the family Selachinematidae (Chromadorida, Selachinematidae, Choniolaiminae) are described from the intertidal sandy sediments of Jeju Island (South Korea). Gammanema okhlopkovi sp. n. is closest to Gammanema anthostoma (Okhlopkov, 2002) and differs by having longer cephalic setae (8.5–19 μm in G. okhlopkovi versus 6–7.5 μm in G. anthostoma) and by the presence of precloacal supplementary organs. The genus diagnosis of Gammanema is updated. The genus includes fourteen valid species, while three species are considered species inquirendae due to incomplete diagnoses and illustrations impeding their correct recognition. An annotated list of valid and invalid Gammanema species is provided. A pictorial key for valid Gammanema species is constructed, which consists of two components: (1) simplified images of heads, and (2) a table summarizing most of the significant measured and numeric characters between species. Latronema obscuramphis sp. n. differs from its related species Latronema aberrans (Allgén 1934), Latronema annulatum (Gerlach, 1953), and Latronema spinosum (Andrássy, 1973) by body size, number of supplementary organs, tail shape, length of spicules, and cuticle ornamentation.