Tensile Properties and Fracture Mechanisms of Corn Bract for Corn Peeling Device Design

This paper describes the physical and tensile properties of corn bracts during a whole harvest period by using two corn cultivars, aiming to realize efficient peeling with minimum energy performance and decrease the incidence of ear damage. The value range and change rule of tensile properties were obtained by combining mechanical experiments and numerical statistics. Meanwhile, mathematical models were established for tensile properties depending on bract moisture content and bract thickness. The experimental results show that the tensile properties of leaf blade were affected by the orientation between pulling force and longitudinal vein, and that parallel orientation was greater than perpendicular. Further, the tensile properties of leaf sheaths depended on the angle between pulling force and natural growth direction of the bract in the following order: 0° > 90° > 180°. A larger pulling force angle can improve the probability of bract fracturing at the root of leaf sheaths, which helps reduce bract residue on the peduncle. In addition, the fracture mechanisms of leaf blades and sheaths were expressed from physiological and morphological perspectives. The experimental results are believed to be able to provide theoretical guidance by which to design and optimize corn-peeling devices.

A new species of Merothrips from the Dampa Tiger Reserve, Mizoram, India (Thysanoptera, Terebrantia)

Merothrips mizoramensis sp.n. is described from northeastern India based on a single macropterous female. The fore wings of this specimen have a single longitudinal vein, the pronotal notopleural sutures are very long with the posteroangular setae displaced laterally, tergite IX lacks trichobothria, and many tergites and sternites bear an unusual number of sculptured lines.

The second genus of the ‘libelluloid’ family Araripephlebiidae (Odonata, Clavilabiata)

The Lower Cretaceous Crato Formation is a well-known Konservat Lagerstätte with a very rich entomofauna. The Odonata are especially very diverse and extensively studied (Bechly, 1998, 2000, 2007, 2010; Nel et al., 1998; Bechly et al., 2001; Bechly & Ueda, 2002) with representatives of all the extant anisopteran main subgroups. This fauna is especially interesting because it comprises some of the oldest and most ‘basal’ groups of the highly diverse extant ‘libelluloid’ dragonflies, or Clavilabiata Bechly, 1996. Among these, the monospecific family Araripephlebiidae Bechly, 1998 is remarkable in the highly specialized hind wing cubito-anal area that contains a curious supplementary longitudinal vein more or less parallel to AA and CuA, unique among the Odonata. Nevertheless, this family remained rather poorly known by three described specimens, only females.

A Gain-of-Function Screen Identifying Genes Required for Growth and Pattern Formation of the Drosophila melanogaster Wing

The Drosophila melanogaster wing is a model system for analyzing the genetic control of organ size, shape, and pattern formation. The formation of the wing involves a variety of processes, such as cell growth, proliferation, pattern formation, and differentiation. These developmental processes are under genetic control, and many genes participating in specific aspects of wing development have already being characterized. In this work, we aim to identify novel genes regulating wing growth and patterning. To this end, we have carried out a gain-of-function screen generating novel P-UAS (upstream activating sequences) insertions allowing forced gene expression. We produced 3340 novel P-UAS insertions and isolated 300 that cause a variety of wing phenotypes in combination with a Gal4 driver expressed exclusively in the central domain of the presumptive wing blade. The mapping of these P-UAS insertion sites allowed us to identify the gene that causes the gain-of-function phenotypes. We show that a fraction of these phenotypes are related to the induction of cell death in the domain of ectopic gene expression. Finally, we present a preliminary characterization of a gene identified in the screen, the function of which is required for the development of the L5 longitudinal vein.

Prospective epidemiological study on the beginning of varicose veins

Summary Objective: To conduct a longitudinal vein study in a young study population on when and how varicose veins develop in healthy veins. Population, method: The initial study population consisting of pupils aged 10–12 (BO I, n = 740) underwent clinical and ultrasound follow-up at the ages of 14–16 (BO II, n = 518), 18–20 (BO III, n = 459) and 29–31 (BO IV, n = 136). During BO I-IV all venous findings detected (including preclinical refluxes of the saphenous veins) were recorded. Results: The data were broken down to reveal the incidence and prevalence of venous refluxes (VR), varicose veins (VV) and venous abnormalities (VA) for each part of the study. Furthermore, the data were analyzed longitudinally to identify any correlations between VR and VV in the two saphenous veins. Conclusions: Since none of the study subjects exhibited VV during BO I, the study permits evaluation of the venous situation in the subjects from birth on. The manifestation of a truncal VV is preceded by a VR in the same vein (p = 0.039). VR occurred mainly during puberty (BO I: 2.5%, BO III: 18.5%, BO IV: 25%). A preclinical VR represents a 30% risk (95% CI: 13–53%) of developing a truncal VV within four years, as a consequence, subsequent preventive 2-year follow-up examinations are recommended.

Does a Varicose Saphenous Vein Exist?

Objective: Duplex ultrasound evaluation of the clinically diagnosed varicose long saphenous vein (LSV). Design: Prospective, single patient group study. Setting: Department of Surgery, University of Ferrara, Italy (teaching hospital). Patients: 378 patients, 509 limbs with primary varicose veins; 94 patients, 103 limbs with a visible, superficial varicose vein trunk on the medial aspect of the thigh. Main outcome measure: Duplex ultrasound detection of a varicose saphenous vein and/or segmental saphenous dilatation and their relationship to saphenous reflux. Results: In 98% of cases the varicose trunk visible in the thigh was demonstrated to be a tributary of the saphenous vein; 34% of the observed saphenous veins exhibited segmental dilatations in the thigh. This finding was related in every case to saphenous vein reflux with high velocity and turbulence ( p < 0.0001). Conclusions: High-resolution ultrasonography demonstrated that when a dilated varicose longitudinal vein trunk is visible and palpable on the medial aspect of the thigh it is most likely to be a tributary rather than the LSV. In addition, a varicose saphenous vein along its entire length essentially does not exist. However, when a dilated saphenous segment occurs, it seems to be related to high diastolic flow velocity and turbulence.

Analysis of the genetic hierarchy guiding wing vein development in Drosophila

The Drosophila rhomboid (rho) and Egf-r genes are members of a small group of genes required for the differentiation of various specific embryonic and adult structures. During larval and early pupal development expression of rho in longitudinal vein primordia mediates the localized formation of wing veins. In this paper we investigate the genetic hierarchy guiding vein development, by testing for genetic interactions between rho alleles and a wide variety of wing vein mutations and by examining the pattern of rho expression in mutant developing wing primordia. We identify a small group of wing vein mutants that interact strongly with rho. Examination of rho expression in these and other key vein mutants reveals when vein development first becomes abnormal. Based on these data and on previous genetic analyses of vein formation we present a sequential model for establishment and differentiation of wing veins.

A Revision of the Genus Nycteribosca Speiser (Diptera Pupipara, Streblidae)

The Genus Nycteribosca was established by Speiser in 1900 for the species which were formerly placed in the genus Raymondia, Strebla or Brachystarsina. This author described one new species and redescribed four others which were already known. Quite recently the number of the species of this genus has been increased to nine by Falcoz. In this paper I have added seven new species, and also give a redescription and figures of all the known species. I have not included N. diversa Frauenfeld in my key, but at the end of this paper there is a description of this fly based on that of Frauenfeld (1856), and a copy of his drawing of the wing. The drawing shows very clearly the branch of the second longitudinal vein. N. diversa appears to be a very doubtful species; it has never been recorded since its original description was written. Moreover, according to Kessel (1925), there is no branching of the second longitudinal vein (R 2+3.) in the family Streblidae.

Notes on the Ethiopian Fruit-flies of the Family Trypaneidae, other than Dacus (s.l.) (Dipt.).—II

This genus was recently described by Dr. Speiser and is a very characteristic one, on account of its elongate and slender body and bare 3rd longitudinal vein. The species belonging here, as long ago pointed out by Loew, have a great resemblance to those of the genus Elaphromyia, but they are at once distinguished by the thin and black occipital row, by the pointed lower angle of the anal cell and by the non-reticulate wing pattern. The genus is evidently allied to Ocneros, but has nothing to do with Rioxa. I will give here some additional details to the short description of Dr. Speiser