Presence Of Projections Research Articles

New integrated evidences reveal male polymorphism and species delimitation in stalk‐eyed fruit flies

AbstractSpecies of stalk‐eyed fruit flies, in the genera Pelmatops Enderlein and Pseudopelmatops Shiraki, have a distinct head structure with eyes located at the ends of stalks, setting them apart from other tephritids. Despite their unique morphology, the intraspecific variation of morphological and behavioural traits in these flies is still not well‐studied, leaving some questions about species definition unresolved. To address this, we conducted a study combining morphological evidence, behavioural studies, and molecular analyses. Our findings revealed male polymorphism in stalk‐eyed fruit flies for the first time, with four morphotypes observed in Pe. fukienensis and three in Pe. ichneumoneus and Ps. angustifasciatus. These morphotypes differ in eyestalk length, wing pattern, and the presence of projections or spikes at the ends of the compound eye. We also propose phylogenetic and phylogeographic implications for the group based on new molecular evidence, along with our observations of courtship and mating behaviours between previously recognized different species. Our study examined four nominal species (Pe. ichneumoneus and Pe. tangliangi, Ps. angustifasciatus and Ps. continentalis) and revealed rich evolutionary interactions within this group. Based on the results, we propose the synonymy of Pe. tangliangi Chen with Pe. ichneumoneus (Westwood) and Ps. continentalis Zia & Chen with Ps. angustifasciatus Zia & Chen.

Why farmers use so many different maize varieties in West Kenya

In this article we reflect on the discussions as to whether breeding and seed system development should proceed along its current well established route of developing varieties with a higher agricultural productivity or if the diversity of farmers, their contexts and rationales requires broader approaches. We make use of data from a recently held survey (2018) in West Kenya. The data show that some 80% of the households in the survey planted both local and hybrid maize varieties. The choices that people make about which variety to plant are many. Apart from rainfall, the availability of cash, the promise of a good yield, the presence of projects and programs and the culture of seed also influences these choices. We argue that an inclusive demand-oriented maize breeding and seed system needs to include a range of varieties and seed sources and to develop and support different delivery pathways to fit farmers’ diverse use of seeds and varieties. Our findings also indicate the need for more systematic study of the diversity of farmers’ rationales and the performance of crop varieties. This would provide useful information for all the actors involved.

Two new tardigrade species (Echiniscidae and Doryphoribiidae) from the Salta province (Argentina).

Tardigrades from Argentina are poorly known. Two new species from the Salta province are described in the present contribution: Pseudechiniscus saltensis sp. nov., and Doryphoribius cephalogibbosus sp. nov. The former species belongs to the novaezeelandiae group and, apart from the nominal species of the group, it is similar to nine congeneric species by the following characters: the absence of spines on legs I and lateral papillae, the scapular plate with a transversal fold, the presence of projections at the posterior margin of the pseudosegmental plate, caudal plate not faceted, and cuticular ornamentation in the form of heads (capituli) of endocuticular pillars, protruding through epicuticle and joined by striae. However, the new species differs from all of them in important qualitative (e.g. colour, different division of plates, details of cuticular ornamentation, claws etc.) and morphometric characters. The new species exhibits a unique morphology of gonopore and anus. Doryphoribius cephalogibbosus sp. nov., by the presence of two macroplacoids, dorsal gibbosities, and inhabiting terrestrial environment, belongs to the flavus group and differs from all members of the group in having ten, instead of nine, rows of gibbosities (X:2-4-6- 6-6-6-6-4-2-2+2[LI-III]), with as a peculiar exclusive character, the presence of the two cephalic gibbosities, never reported in other Doryphoribius species. Moreover, the new species differs from the other species of the group by morphometric and more detailed morphological characters. The new species description also gave an occasion to discuss the issue of gibbosity arrangement in other species and address the morphology of claw accessory points.

Tanap, a new robber fly genus from Turkey (Diptera: Asilidae: Dioctriinae).

Tanap gen. nov. and Tanap cinar sp. nov. (Diptera: Asilidae) from Turkey are described and illustrated. This new genus is distinguished from all extant Asilid genera by the presence of projections just behind at the base of the antenna. A key to the Palaearctic genera of Dioctriinae is provided.

Qualitative Evaluation of the Bracket-Adhesive-Enamel Junction of Metal Orthodontic Brackets: A Preliminary Report.

The purpose of this in vitro investigation was to evaluate qualitatively the surface topography at the bracket-adhesive-enamel junction, bonded to the buccal and lingual surfaces of premolars with composite resin and resin-modified glass-ionomer orthodontic adhesives, using two methods of adhesive removal: a dental explorer and a micro brush. Forty premolar surfaces were allocated to four groups of 10/ each, 20/buccal and 20/lingual surfaces. The brackets were bonded to the surface of the enamel and any extra adhesive was removed with a dental explorer or a micro brush. Specimens were evaluated and scored by two calibrated independent raters, at the bracketadhesive-enamel junction, for adhesive overlap on the bracket, the smoothness of the surface, as well as the presence of projections and depressions, using a digital microscope. The Fisher-exact statistical test was conducted to compare the different groups. Regardless of the method used to remove the adhe sives, all groups showed partial or complete overlap of the adhesive on the bracket. No statistical difference was found between the groups for adhesive overlap (P=1.0). However, resin-modified glass-ionomer was found to be statistically significantly (P<0.05) better than composite resin in both smoothness and the lack of projections or depressions, regardless of the instrument of removal. Removing excess adhesive with a dental explorer or a micro brush is not an ideal method for adhesive removal, as partial or complete overlap of the adhesive on the bracket existed in all groups. On the other hand, resin-modified glassionomer was a superior material to composite resin for better smoothness and surface topography at the bracket-adhesive-enamel junction.

The study of the impact of ice conditions on the possibility of the submarine vessels surfacing in the ice cover

Traditionally submarine vessels emerging from under ice cover performing by static loading of ice from bellow through the creation of positive buoyancy by main ballast tanks. However thickness of ice (approximately 1 meter) from under which modern submarine vessel can emerge essentially limits the use of traditional method, particularly during submarine vessels motion in the severe ice conditions of Arctic region. For breaking the ice cover of greater thickness can be used flexural gravity waves caused by the submarine vessel motion with certain critical speed near the bottom ice. It is also known that in the coastal areas water depth is often less than 100 meters, and the presence of projections on the bottom surface may effect on the wave propagation pattern. This paper presents experimental study of influence of bottom contour on the deflection and the length of the flexural gravity waves from the movement of submarine. Ice cover failure pattern determined. Assessment of ice-breaking capacity of flexural-gravity waves with using the criterion of ice failure is performed.

Principais caracteres da osteologia craniana de Milvago chimango (Vieillot, 1816) e Milvago chimachima (Vieillot, 1816) (Aves: Falconidae)

Knowledge of details of the cranial osteology of Milvago chimango and M. chimachima helps to ensure the monophyly of genus when compared to other birds and falcons. We conducted a study using skulls of three Milvago chimango and three Milvago chimachima specimens from the Smithsonian Institution National Museum of Natural History's Division of Birds. The cranial descriptions were comparative and illustrated by photos from the dorsal, ventral, and lateral flow perspectives. The studied species were then compared with falcons and other birds. Milvago chimango possesses several unique characters, including: the ratio of the distance from the distal portion of the lacrimal bone to the orbital arc, and from the orbital arc to the buccal arc is (1/5); absence of transpalate processes; lack of dorsal process on the pterygoid bone; more robust skull; paraoccipital bone more developed laterally; lacrimal bone smaller and more rostral; palatine bone approximately twice as wide; ethmoide bone more robust and long. In M. chimachima, the distinguishing features are: presence of projections at the caudal end of the palatine bone; developed dorsal process of the pterygoid bone; temporal fossa more tapered dorsoventrally; transverse nuchal crest outlined and visible; nostril closer to the frontonasal suture. Cranial osteology successfully provided diagnostic characters of each species and gender compared to other birds and falcons. to the installation of large enterprises or environmental protection areas. alic'>seedlings.

Grassroots projects aimed at the built environment: Association with neighbourhood deprivation, land-use mix and injury risk to road users.

1) To describe grassroots projects aimed at the built environment and associated with active transportation on the Island of Montreal; and 2) to examine associations between the number of projects and indicators of neighbourhood material and social deprivation and the built environment. We identified funding agencies and community groups conducting projects on built environments throughout the Island of Montreal. Through website consultation and a snowballing procedure, we inventoried projects that aimed at transforming built environments and that were carried out by community organizations between January 1, 2006, and November 1, 2010. We coded and validated information about project activities and created an interactive map using Geoclip software. Correlational analyses quantified associations between number of projects, neighbourhood characteristics and deprivation. A total of 134 community organizations were identified, and 183 grassroots projects were inventoried. A large number of projects were aimed at increasing awareness of/improving active or public transportation (n=95), improving road safety (n=84) and enhancing neighbourhood beautification and greening (n=69). The correlation between the presence of projects and the extent of neighbourhood material deprivation was small (Kendall's t=0.26, p&lt;0.001), but in areas with greater social deprivation there were more projects (Kendall's t=0.38, p&lt;0.001). Larger numbers of projects were also associated with the presence of more extensive land-use mix (Kendall's t=0.23, p&lt;0.001) and a greater proportion of road intersections with injured pedestrians, cyclists and motor vehicle users (Kendall's t=0.43, p&lt;0.001). There is significant community mobilization around built environments and active transportation. Investigations of the implementation processes and impacts are warranted.

Pericarp ontogenesis in wild species of Arachis L. (Leguminosae; Papilionoideae)

The genus Arachis encompasses 80 validly described species and the most striking characteristics is the geocarpic fruit, which occurs in every species of the genus. Taking into consideration that much of the current knowledge about this subject is based on the anatomy and morphology of A. hypogaea, a cultivated species with fruits that were modified during domestication, the objective of this study was to learn more about the development of the geocarpic fruits of wild species of Arachis (A. paraguariensis, A. pintoi, A. stenosperma, and A. tuberosa), and to provide characters that can be used in future phylogenetic works about this group. Buds, flowers and fruits at different stages of development were collected and processed according to standard methods used for light field, interferential contrast, and scanning electron microscopy. Although the geocarpic fruits of the wild species share many adaptations, this study identified potentially diagnostic infrageneric characters, such as the type of trichomes on the pericarp, the presence of sclerenchyma caps in the bundles of the pericarp of the seed chamber of the fruit and isthmus, the presence of tracheoid cells in the pith of the isthmus, the location of crystalliferous cells, the presence of tannins in the cells of mesocarp outer layers, and the presence of projections in the sclerenchyma tissue. In addition, this article brings some inferences about functional characteristics of this peculiar geocarpic fruit.

Basal Ganglia Circuits: What's Now and Next?

Basal Ganglia Circuits: What's Now and Next?

Cartilage damage involving extrusion of mineralisable matrix from the articular calcified cartilage and subchondral bone

Arthropathy of the distal articular surfaces of the third metacarpal (Mc3) and metatarsal (Mt3) bones in the Thoroughbred racehorse (Tb) is a natural model of repetitive overload arthrosis. We describe a novel pathology that affects the articular calcified cartilage (ACC) and subchondral bone (SCB) and which is associated with hyaline articular cartilage degeneration. Parasagittal slices cut from the palmar quadrant of the distal condyles of the left Mc3/Mt3 of 39 trained Tbs euthanized for welfare reasons were imaged by point projection microradiography, and backscattered electron (BSE) scanning electron microscopy (SEM), light microscopy, and confocal scanning light microscopy. Mechanical properties were studied by nanoindentation. Data on the horses' training and racing career were also collected. Highly mineralised projections were observed extending from cracks in the ACC mineralising front into the hyaline articular cartilage (HAC) up to two-thirds the thickness of the HAC, and were associated with focal HAC surface fibrillation directly overlying their site. Nanoindentation identified this extruded matrix to be stiffer than any other mineralised phase in the specimen by a factor of two. The presence of projections was associated with a higher cartilage Mankin histology score (P<0.02) and increased amounts of gross cartilage loss pathologically on the condyle (P<0.02). Presence of projections was not significantly associated with: total number of racing seasons, age of horse, amount of earnings, number of days in training, total distance galloped in career, or presence of wear lines.

Adaptations of Anomopoda crustaceans (Cladocera) to the benthic mode of life

Crustaceans of the order Anomopoda inhabit both pelagic and littoral zones of fresh water bodies. Different adaptations to the benthic mode of life in representatives of different families and genera of this order are described. They include incomplete molting, the presence of a mucous film on the body surface, protection of the head from frontal damage, large lateral projections on the valves and additional sculpture on the head and valves, well-developed lateral armature of the postabdomen, the presence of projections on the postabdomen preanal margin, specialization of setae and spines of the second antenna, especially large exopodites on limbs IV and V, a reduced compound eye, and a large, well-developed ocellus. Similar adaptations to the benthic mode of life in the Anomopoda and Ostracoda are discussed.

Control of serotonergic neurons in the dorsal raphe nucleus by the lateral hypothalamus

Anatomical evidence indicates the presence of projections from the lateral hypothalamus to serotonergic (5-hydroxytryptamine, 5-HT) neurons of the dorsal raphe nucleus (DR). Using dual probe microdialysis and extracellular recordings in the DR, we show that the application of GABAergic agents in the lateral hypothalamus modulates the activity of 5-HT neurons in the DR. GABA and bicuculline or baclofen, applied in the lateral hypothalamus significantly reduced and increased, respectively, the 5-HT output in the DR. Likewise, the intrahypothalamic application of GABA and bicuculline reduced (14/20 neurons) and increased (8/12 neurons), respectively, the firing rate of 5-HT neurons in the DR. A smaller percentage of neurons, however, were excited by GABA (3/20) and inhibited by bicuculline (1/12). Application of tetrodotoxin in the lateral hypothalamus suppressed the local 5-HT output and reduced that in the DR. The 5-HT output in the DR increased transiently soon after darkness. The hypothalamic application of GABA attenuated and that of bicuculline potentiated this spontaneous change with an efficacy similar to that seen in light conditions. These results indicate that the lateral hypothalamus is involved in the control of 5-HT activity in the DR, possibly through excitatory (major) and inhibitory (minor) inputs.

Book Review

Book Review

Chest wall distortion and discharge of pulmonary slowly adapting receptors.

We assessed the effects of chest wall distortion, changes in lung volume, and abolition of airway smooth muscle tone on the discharge patterns of 92 pulmonary slowly adapting receptors (SAR) in decerebrate, spontaneously breathing cats. Distortion resulted from their inspiratory efforts against an occluded airway at functional residual capacity and at increased end-expiratory lung volumes. Approximately 40% of SAR increased discharge frequencies during occlusions. Modulation of SAR discharge during occlusions persisted after administration of atropine to eliminate airway smooth muscle tone. Phasic modulation of SAR discharge was eliminated during no-inflation tests after paralyzing the cats and ventilating them on a cycle-triggered pump. We conclude 1) parasympathetic modulation of airway smooth muscle tone makes no obvious contribution to SAR discharge in spontaneously breathing cats; 2) the no-inflation test (withholding of lung inflation during neural inspiration) in paralyzed and ventilated cats is a valid test for the presence of projections from SAR to medullary respiratory neurons; and 3) in the absence of tidal volume changes, distortion stimulates some SAR. Sensory feedback from receptors in the lung, not just those in the chest wall, may therefore provide information about abnormal chest wall configurations.

The origins of descending spinal projections in lepidosirenid lungfishes.

The origins of descending spinal projections in the lepidosirenid lungfishes were identified by retrograde transport of horseradish peroxidase (HRP) introduced into the rostral spinal cords of juvenile African (Protopterus annectans and Protopterus amphibians) and South American (Lepidosiren paradoxa) lungfishes. Standard HRP histochemistry revealed retrogradely labeled neurons in the nucleus of the medial longitudinal fasciculus, midbrain tegmentum, red nucleus, optic tectum, mesencephalic trigeminal nucleus, granule cell layer of the cerebellum, superior, middle, and inferior medullary reticular nuclei, magnocellular and descending octaval nuclei, region of the descending trigeminal tract, solitary complex, and the margins of the spinal gray matter anterior to the spinal HRP implant. A small number of retrogradely labeled neurons were also present in the ventral thalamus of Protopterus. A descending spinal projection from the forebrain was not evident in either genus of lepidosirenid lungfishes. The presence of projections to the spinal cord from the diencephalon, medial reticular formation of the midbrain and medulla, octaval (vestibular) nuclei, solitary complex, and probable nucleus of the descendin trigeminal tract in lungfishes and their overall similarity to comparable projections in other vertebrates suggest that these pathways are among those representative of the primitive pattern of descending spinal projections in vertebrates.

An anatomical investigation of projections from lateral geniculate nucleus to visual cortical areas 17 and 18 in newborn kitten.

The presence of projections from the lateral geniculate nucleus to visual cortical areas 17 and 18 in newborn kitten was examined using the method of retrograde axonal transport. An injection of either horseradish peroxidase (HRP) or horseradish peroxidase conjugated to wheat germ agglutinin (HRP-WGA) was made into area 17 on one side of the brain and area 18 on the other side. The results were not unlike those from experiments on adults. Area 17 injections label a relatively high proportion of cells in laminae A and A1 and the distribution of sizes of labelled cells is almost the same as that for the total cell population. Area 18 injections label only a small percentage of the total cell population in laminae A and A1 and most of the labelled cells are large. Cells in the C layers are labelled after an injection into either area 17 or 18. It was concluded that the formation of organized thalamocortical projections in the kitten does not rely on visual experience as the projections are already present at birth.

Importance of new catecholamine pathways in control of blood pressure.

The first comprehensive maps of central catecholamine pathways referred to both noradrenaline and dopamine neurons. They described the catecholamine neurons as having their cell bodies in the brainstem with spinal axons descending mainly from two medullary cell groups (A1 and A2) and with ascending axons arising mainly from more rostral groups (A3-A13). More recent work utilising immunohistochemistry has established the presence of adrenaline neurons in the brain, in two medullary cell groups (C1 and C2). While these were originally thought to lie within the rostral part of the A1 and A2 cell groups, work from this laboratory has now established that the adrenaline neurons are topographically distinct from the A1 and A2 cells, do not fluoresce with standard methods, and are collected into three groups, the third group (C3) lying in the midline of the rostral medulla. Work in this laboratory using a combination of histochemical fluorescence and retrograde transport of horseradish peroxidase has demonstrated that existence of a descending dopaminergic projection from the hypothalamus to the spinal cord, indicating that descending pathways can arise well above the medulla. Recent studies on the A1 neurons have established the presence of projections from the A1 cells to the median eminence of the hypothalamus and towards the nucleus tractus solitarius in the medulla. Other experiments have demonstrated that most of the descending catecholamine axons do not arise from the A1 and A2 cell groups in the caudal medulla, but higher up in the brainstem especially from the A5 and A7 cell groups. These new descriptions of central catecholamine neurons will necessarily modify the interpretation of many experiments on the central regulation of arterial pressure.

Sural nerve effects on medial gastrocnemius motoneurones in the cat.

1. Excitability cycles for medial gastrocnemius motoneurones were recorded following sural nerve stimuli with amplitudes of 1.5, 3, 5, 10 and 40 times the nerve threshold. The monosynaptic reflex was time-integrated to quantify the motoneuronal output and some implications of this technique are discussed. In particular it is calculated that this method specifically examines the 15-25% most excitable motoneurones of the medial gastrocnemius pool.2. In most cases high amplitude stimulation of the sural nerve caused a triphasic (excitatory-inhibitory-excitatory) change in excitability. Arguments are given to support the conclusion that this represents a corresponding post-synaptic alteration in medial gastrocnemius motoneurone potential. It is concluded that this pattern illustrates the nature of the sural nerve projections to this portion of the medial gastrocnemius pool.3. The first period of excitation began after a latency, corrected to be compatible with intracellular recordings, of 2.8 ms and had a mean duration of 4.0 ms. The minimum stimulus level necessary for this effect lay between 1.5 and 3 times the nerve threshold. The maximum amplitude of this facilitation occurred with stimuli of 3-5 times threshold and was 60-90% of the amplitude of the monosynaptic facilitation which followed stimulation of the lateral gastrocnemius-soleus nerve.4. A period of inhibition followed immediately after the period of excitation and had a mean duration of 16 ms. The minimum stimulus level necessary for this effect lay between 1.5 and 3 times the nerve threshold and the degree of inhibition increased with stimuli up to 40 times threshold.5. The second period of excitation lasted a mean period of 50 ms and was due to activity in high threshold fibres. On average its amplitude was 50% that of the initial excitation.6. Exceptions to this triphasic variation of excitability were found. This result is interpreted as indicating the presence of projections with opposing actions which were simultaneously activated by sural stimuli.

Surface Structure of Intestinal Epithelium

Summary Specimens of human and rat small intestine were studied by scanning electron microscopy. Human specimens were examined intact, while rat specimens were studied after partial or complete dissociation of epithelium from the underlying villus core. The present technique confirms, in a simple, direct way, previous concepts of the three-dimensional structure of intestinal epithelium, concepts derived from reconstruction of serial sections studied by light and transmission electron microscopy. Several features not readily discerned by these latter techniques but shown by this study were (1) the occurrence of epithelial cells in groups, (2) the presence in the epithelial surface of cavities or pores which probably represent the orifices of goblet cells, (3) the polygonal outline presented by the luminal surface of epithelial cells, (4) the pliable nature of microvilli, and (5) the presence of projections from the lateral walls of epithelial cells after their partial dissociation. The occasional finding of apparent connections between lateral surfaces of epithelial cells suggests that these latter projections represent broken intercellular bridges.