Morphological patterns of the intraparietal sulcus and the anterior intermediate parietal sulcus of Jensen in the human brain

Distinct parts of the intraparietal sulcal cortex contribute to sensorimotor integration and visual spatial attentional processing. A detailed examination of the morphological relations of the different segments of the complex intraparietal sulcal region in the human brain in standard stereotaxic space, which is a prerequisite for detailed structure-to-function studies, is not available. This study examined the intraparietal sulcus (IPS) and the related sulcus of Jensen in magnetic resonance imaging brain volumes registered in the Montreal Neurological Institute stereotaxic space. It was demonstrated that the IPS is divided into two branches: the anterior ramus and the posterior ramus of the IPS, often separated by a submerged gyral passage. The sulcus of Jensen emerges between the anterior and posterior rami of the IPS, and its ventral end is positioned between the first and second caudal branches of the superior temporal sulcus. In a small number of brains, the sulcus of Jensen may merge superficially with the first caudal branch of the superior temporal sulcus. The above morphological findings are discussed in relation to previously reported functional neuroimaging findings and provide the basis for future exploration of structure-to-function relations in the posterior parietal region of individual subjects.     

Septins regulate border cell surface geometry,shape, and motility downstream of Rho in Drosophila

1. Download : Download high-res image (260KB)
2. Download : Download full-size image

     

Justification for the generic status of Courtoisina (Cyperaceae)

In the past, the two species of Courtoisina were placed either in Cyperus L., Mariscus Vahl, or in Courtoisia Nees (now Courtoisina Sojak). While these species show undoubted external similarities to both Cypm and Muriscus , they differ by their widely winged glumes and the arrangement of the veins of the glumes. They also differ profoundly from Mariscus and most species of Cypm in anatomical characteristics, and it is concluded that these differences warrant separate generic status.     

Geometric morphometrics reveal male genitalia differences in the Lasiommata megera/paramegaera complex (Lepidoptera, Nymphalidae) and the lack of a predicted hybridization area in the Tuscan Archipelago

The recognition of specific demarcation between allopatric populations, as for island endemics, is particularly difficult according to the Biological Concept of Species. However, the recognition of the specific status of island taxa is decisive in evaluating important areas of endemism for conservation purposes. The recent taxonomic inflation of European butterfly species calls into question the validity and objectivity of taxonomic practices, and of databases dependent on them, which are used in biogeography and conservation. In this paper I applied rigorous morphometric analyses instead of visual evaluation to solve the long debated question of whether Lasiommata paramegaera butterfly from Sardinia and Corsica should be considered as a separated entity from the widespread Lasiommata megera . First, I carried out analyses of male genitalia shape comparing the populations from Corsica and Tuscany. Thereafter, I also searched for possible hybridization evidence in the sole area where it is strongly predicted: the Tuscan Archipelago. These islands are located between Tuscany and Corsica and there is large evidence of a continuous immigration of butterflies from these two main sources. I found that Corsican L. paramegaera and Tuscan L. megera can be clearly distinguished on the basis of genitalia shape. Furthermore, the Lasiommata population of each islet clearly maintains the characteristics of one of the two species without evidence of intermediate individuals. In conclusion, I suggest that the two entities should be considered as separate species maintaining their homogeneity by a reduced gene flow across sea, mating avoidance and/or by some depletion of F1 hybrids in developmental or mating success.     

Morphological changes during fiber type transitions in low-frequency-stimulated rat fast-twitch muscle

This study investigates morphological adaptations of rat extensor digitorum longus muscle to chronic low-frequency stimulation (10 Hz, 10 h/d, up to 61±7d). During the early stimulation period (2–4 d), increased basophilia and accumulation of RNA were seen predominantly in type-IIB fibers. Putative satellite cell activation, as indicated by ³H-thymidine incorporation, was also evident during this phase. By 12 d, fiber composition remained unaltered, but there was a decrease in the cross-sectional area of the type-IIB fibers. Following 28 d of low-frequency stimulation, the percentage of type-IIB fibers decreased from 43±3% to 0%, while type-IID fibers increased from 30±3% to 60±6%. The fraction of type-IIA fibers tended to increase (controls 19±3%; stimulated 29±4%), whereas that of the type-I fibers was unaltered (4±1%). At this time, the cross-sectional area of type-IID fibers was unaltered, but that of type-IIA and type-I fibers increased. Further stimulation resulted in a return of type-IID fibers to control levels (23±5%), and a marked increase in type-IIA fibers (45±8%). The percentage of type-I fibers increased from 4±1% to 8±1%. Throughout each stage of chronic stimulation, there was no histological evidence of fiber degeneration and regeneration. These results indicate that, in contrast to the rabbit, chronic low-frequency stimulation-induced fiber conversion in the rat extensor digitorum longus muscle is entirely due to fiber transformation.     

Evaluation of leaf features in forest trees: Methods,techniques, obtainable information and limits

Tree leaves are interfaces between the whole organism and the environment. Leaves display a series of attributes that are linked to specific functions (functional leaf traits—FLT) and/or show responses to biotic and abiotic stress factors (stress response traits, SRT), which can be subdivided into: (a) morphological traits; (b) chemical traits; (c) physiological traits; (d) symptoms. The analysis of FLT is a useful tool for tree species and provenance phenotyping, due to the adaptation of trees to environmental stress. Additionally, FLT can be used as response factor in long term and large spatial scales surveys of forest conditions. Despite these potential benefits of leaf traits in the assessment of ecosystem health and functioning, leaf sampling in forests is time-consuming and costly, especially in forests with a complex vertical and horizontal structure and in remote forest areas. Once a foliar sample has been collected, many different analyses can be carried out; however, analyses should be technically simple and able to be performed within one day following the leaf collection (i.e., on fresh samples), or after air-drying the leaves themselves (analysis of dried specimens). This paper reports the results of leaf sampling and foliar analyses carried out in previous research projects and revises the current state-of-the-art. The leaf traits that are easily obtainable from leaf sampling are listed, together with the operational procedures necessary for their measurement, described in a standardized protocol. Their ecological and functional relevance is discussed in relation to their potential information (as indicators of climatic stress, drought, air and soil pollution, tree light-use and competition, plant nutritional status, health and general plant stress conditions). Finally, this review provides suggestions for the elaboration and reporting of data, and proposes some guidelines to improve the effectiveness of foliar analysis in the assessment of forest ecosystem health, properties and functioning.     

Carayonovus n. gen. from Reunion Island – aberrant new genus of Anthocoridae or representative of a new family (Heteroptera: Cimicoidea)?

Carayonovus insignis n. gen., n. sp., a remarkable new genus and species of Heteroptera, is described from Reunion Island. It is tentatively placed in the family Anthocoridae (Cimicoidea), but because of its remarkable sexual dimorphism and possession of characters not normally associated with this family or even with Cimicoidea, the genus is discussed in terms of the validity or otherwise of including it in these taxa. Its habitat preference is also examined.     

Comparison of diurnal variation of airborne pollen in Mar del Plata (Argentina)

Intradiurnal variation of arboreal pollen (AP) in Mar del Plata city is compared during three non - consecutive years of survey and described in relation to the associated weather. The daily pattern of pollen abundance has a maximum between 10:00 and 12:00?h, while a minimum occurs at 18:00?h. The first two years of survey showed homogeneous daily trends, but in 1995 the maximum and minimum concentrations were delayed because of the change in position of the collecting station. Arboreal pollen spectrum presented qualitative and quantitative changes in the three years analysed. Results indicate optimal conditions for diurnal dispersion of arboreal pollen are high temperatures and low relative humidity. Also interaction between source position and wind direction has important effects on the timing of the peaks of some pollen types.     

Morphological and Morphometrical Characterization of Meloidogyne incognita from Different Host Plants in Four Districts of Punjab,India

The population of M. incognita, the root knot nematode (RKN) was found infesting five different host plants (okra, banana, sunflower, bottle gourd, and brinjal) out of 24 examined from four districts of Punjab, India (Gurdaspur, Ludhiana, Patiala, and Hoshiarpur). Morphological and morphometrical characterization indicated that in the case of mature female, the characters of body length and width, neck length, ratio ‘a’, anus to tail terminus (ATT), interphasmid distance (IPD), and perineal pattern were recorded as stable characters. These taxonomic characters can be reliable for identification. All characters of second-stage juvenile (J2) such as body length, stylet length, head to median bulb length (H-MB), distance from median bulb to excretory pore (MB-EP), tail length, anal body width (ABW), and ratios C and C’ were highly variable. Analysis of interpopulation morphometric characters of mature female of M. incognita, namely, body length, width, and ratio ‘a’ were moderately variable characters (CV 0.26% to 20%) and stylet length, neck length, length of median bulb (LMB), and width of median bulb (WMB) were highly variable (CV 1.0% to 36.1%). In the perineal pattern, the two characters ATT and IPD were moderately variable (CV 8.8% to 17.6%) and two characters, anus to vulval slit (AVS) and length of vulval slit (LVS), were highly variable (CV 2.1% to 40.5%). In J2, body length, stylet length, H-MB, MB-EP, ABW, tail length, ratios C, and C’ were highly variable characters (CV > 12%).