Notes on Neotropical Veliidae (Hemiptera). IX: additional new species of Paravelia from South America

Four new species of Paravelia are described: P. dilatata from Surinam and Brazil; P. foveata, P. cupariana and P. juruana from Brazil

A new species, new synonymy, and notes on Paravelia Breddin (Hemiptera: Heteroptera: Veliidae)

The broad-shouldered water strider Paravelia cunhai sp. nov. is described and illustrated based on material from the state of Pará, northern Brazil. The new species can be distinguished from all other species in this genus mainly by the dark color of the head and pronotum, absence of pruinosity or silvery pubescence on the anterior lobe of pronotum, maculae pattern on the fore wings, hind femur with row of 22 spines on mesal margin, and general shape of the paramere. This new species was collected in a pool inside a cave without incident light, a habitat recorded for the genus only recently, which reinforces the hypothesis that some species of Paravelia have troglophilic habits. In addition, a photograph of the dorsal habitus and notes concerning P. juruana Polhemus & Polhemus are provided, and P. cupariana Polhemus & Polhemus syn. nov. is proposed as a junior synonym of P. spinifera Polhemus & Polhemus

Concurrent validity and test-retest reliability of the Polhemus Liberty for the measurement of spinal range

This paper discusses concurrent validity and test-retest reliability of the Polhemus Liberty for the measurement of spinal range.It was presented at the International Society of Biomechanics, XXII World Congress, in 2009

A new Potamobates Champion species (Heteroptera: Gerridae) from Ecuador with new distribution records for P. williamsi

Potamobates sumaco new species is described from the Ecuadorian Amazon. Male and female genitalia differentiate P. sumaco from a similar parapatric species, P. williamsi Hungerford. Phylogenetic analysis indicates P. sumaco is closely related to the species of the P. tridentatus group which includes P. williamsi. A distribution map and revised key to Potamobates species are provided.Se describe Potamobates sumaco nueva especies del Amazonas Ecuatoriano. Los genitales del macho y la hembra distinguen P. sumaco de la especie mas cercana P. williamsi Hungerford. El analisis filogenetico indica que P. sumaco partenece al grupo P. tridentatus. Se incluye un mapa de la distribucion y una clave modificada para la identificacion de las especies de Pomatombates

Study made to establish parameters and limitations of explosive welding

It is theorized that metal jetting must be present for welding to occur, therefore an explosive weld interface may indicate the relation between the metal jet velocity and shock wave velocity in welding. Parameters for effecting explosive welding in patches of 3 or 4 inches in diameter were established, and found applicable to explosive welding of patches of various sizes

Life History of \u3ci\u3eMesovelia Mulsanti\u3c/i\u3e (Hemiptera: Mesoveliidae) in Southern Illinois

The life history of Mesovelia mulsanti was studied during 1983-1986. This species was apparently trivoltine with a partial 4th generation at the end of the year. It overwintered as eggs. First ins tars appeared in mid-April followed by marked overlapping of the subsequent instars and generations. The first adults appeared in early May. No active individuals were found after November

On a new species of intertidal water strider from Brazil (Hemiptera, Gerromorpha, Mesoveliidae)

This paper deals with the description of a new species of Hemiptera, Gerromorpha, Mesoveliidae, from Marudá, State of Pará, Brazil - Darwinivelia polhemi n. sp. Illustrations of habitus, genitalia and other morphological parts are also included

The Caltech helicopter control experiment

This report describes the Caltech helicopter control experiment. The experiment consists of an electric model helicopter interfaced to and controlled by a PC. We describe the hardware and software. A state-space model for the angular position is identified from experimental data near hover, using the prediction error method. An LQR controller with integrators for set point tracking is designed for the system. We also undertake a separate identification and loop shaping control for the yaw dynamics

On a dragonfly collection from the Solomon Islands with overview of fauna from this Pacific archipelago (Insecta: Odonata)

Odonata fauna of the Solomon Islands (considered in its political rather than geographical borders) is revised following a recent collecting trip to Guadalcanal Island in April 2012. Some important taxonomic considerations are discussed and a complete literature review is provided for the country with an updated checklist of 64 species that is in accordance with the latest taxonomic studies on the group from that part of the world. The collection reported here was carried out on two and a half effective field days and resulted in a total of 30 taxa. Two of them (Agyrtacantha browni and Gynacantha amphora) are new to science and already described elsewhere and three oth-ers (Lestesconcinnus, Lathrecista asiatica festa and Rhyothemis resplendens) are new to the country. A female of Pseudagrion incisurum is described for the first timeand another female (Rhinocypha liberata) will be described later