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Volvo B7TL

The Volvo B7TL is a low-floor double-decker bus chassis, launched in 1999 and replaced the 2-axle version of the Volvo Olympian. It was built as the British bus operators seemed hesitant to purchase the B7L double decker with a long rear overhang; the B7TL chassis was designed by the Leyland Product Developments consultancy based at the Leyland Technical Centre. It was built in Irvine, North Ayrshire, Scotland. In 2000, production was transferred to Sweden. In mid-2004, production of the MkII version of the B7TL was started. Like the Olympian, the B7TL features a transversely-mounted rear engine and a shorter rear overhang, but the radiator was mounted on the right side of the engine compartment, it was equipped with ZF or Voith gearbox. The B7TL was available with Alexander ALX400 and Plaxton President bodywork followed by East Lancs Vyking and Myllennium Vyking bodies, the Wright Eclipse Gemini; the Volvo B7TL was popular in the United Kingdom, with a large number being purchased by most of the major bus groups such as FirstGroup and Arriva.

Travel West Midlands purchased over 320 B7TLs with Plaxton President, Alexander ALX400 and Wright Eclipse Gemini bodies. Translink of Northern Ireland purchased over 150 B7TLs; the last Volvo B7TLs entered service with First Glasgow with the Wright Eclipse Gemini bodywork in April 2007. Southern Vectis at the end of 2001 ordered seven Volvo B7TLs with Plaxton President Bodywork; the model was popular with a number of operators having placed orders. It was popular in the Republic of Ireland, Dublin Bus acquired 648 B7TLs between 2000 and 2007, all with Alexander/TransBus/Alexander Dennis ALX400 bodywork. Bus Éireann purchased more than twenty B7TLs. On the other hand, a batch of 150 B7TLs had been delivered to Johannesburg, South Africa in 2002 and were fitted with Marcopolo Viale DD bodywork. A Volvo B7TL with East Lancs Vyking bodywork operated by Lincolnshire RoadCar was involved in an accident in Ingoldmells, Lincolnshire, on 11 April 2004 in which five people died and six more were injured, two critically.

Despite the bus being found to have faulty brakes following the accident, this did not contribute to the accident, there have been no further reports of similar braking problems involving Volvo B7TLs. The Volvo B7TL was superseded by the 2-axle version of the Volvo B9TL in late 2006. Competitors Dennis Trident 2 Scania OmniDekka VDL DB250List of buses

Hatz CB-1

The Hatz CB-1 is a 1960s American light biplane designed by John Hatz for amateur construction. The Hatz Classic variant is supplied in kit form by Makelan Corp of New Braunfels, while the other variants are available as plans only. John Hatz designed the CB-1 in 1968 as a smaller version of a Waco F series biplane; the CB-1 is a tandem dual-control two-seat biplane with fixed tailwheel landing gear and powered by a variety of nose mounted small engines. Steel tube tail with wooden wings. Plans and kits of parts for the CB-1 are available for amateur construction. CB-1 Base model Hatz Classic Designed by Billy Dawson, which has a stretched more rounded fuselage and powered by a Lycoming O-320. Kelly-D A simpler and larger variant of the Hatz, with the wing center section removed, designed by Dudley Kelly. Hatz Bantam A lighter model. General characteristics Crew: 2 Length: 18 ft 10 in Wingspan: 25 ft 4 in Height: 7 ft 10 in Wing area: 178 ft2 Empty weight: 850 lb Gross weight: 1450 lb Powerplant: 1 × Lycoming O-320, 100-150 hp Performance Maximum speed: 105 mph Range: 250 miles Service ceiling: 12,000 ft Aircraft of comparable role and era Westfall Sport Taylor, Michael J. H..

Jane's Encyclopedia of Aviation. London: Studio Editions. Aerofiles Official website - Hatz CB-1 Official website - Hatz Classic kit supplier Official website - Hatz Bantam kit supplier

Brasilodon

Brasilodon is an extinct genus of cynodonts that lived during the Norian age of the Late Triassic Period, about 228 to 208.5 million years ago. The average length of Brasilodon is 12 cm and weighed about 20 grams; the average size of this cynodont species is about the size of extant mice. Brasilodontids are most insectivores due to their teeth; the two species in this genus are B. tetragonus and B. quadrangularis, two small cynodonts belonging to the family Brasilodontidae. Brasilodon is a genus of small derived cynodont that exhibits many mammalian features including a secondary palate, symmetrical tooth development, more developed sense of hearing than other cynodonts; the study of Brasilodons shows that the expansion of advanced cynodonts with mammalian features occurred in several species that still retained many primitive features. Skull size in Brasilidontids varies from individual to individual about 35-40%, is about 20% larger than Brasilitherium, the other genus in the family Brasilodontidae.

Brasilodon species lack a prefrontal bone, postorbital bone, postorbital bar, seen in most other Probainognathians. Some derived features shown in Brasilodon include: reduced postdentary bones, nasal-frontal bone contact on the lateral sides, reduced canines close to the size of the last incisor, the vascular features of their "stapedial recess"; the well developed stapedial process, as well as the presence of several foramina in Brasilodon indicates that the middle ear of Brasilodontids was another feature showing that it is a more derived Probainognathian. The interpterygoid vacuity seen in Brasilodontids is considered to be derived or a reversed character of the primary palate found in mammals, which extends from the choana to the interpterygoid vacuities; the presence of a secondary palate shows another derived feature found in Brasilodon, the posterior end of the secondary osseous palate extends posteriorly to the last postcanine. Brasilodon quadrangularis is characterized by quadrangular upper and lower postcanines, which are secured to the jaw by ossified periodontal ligament in the root.

Each tooth row contains 8-9 lower postcanines. The upper postcanines are smaller than lower postcanines, a condition observed in many Probainognathians. Brasilodon can be differentiated from Brasilitherium by its more derived lower postcanines; this consists of a prominent central cusp, an anterior accessory cusp, a posterior accessory cusp, resulting in a symmetrical distribution. The postcanines seen in Brasilitherium, on the other hand, has morganucondontid-like plan in lower postcanines. Due to the size of the diastema between canines and postcanines in the largest Brasilodontids, this shows that anterior postcanines were most lost faster than it was in Thrinaxodon. Although it is not known how many successional postcanine replacements there are in Brasilodon, there is more than one replacement, it is done the same way as many cynodonts, in which postcanines are replaced in an alternate manner. Postcanine replacement in Brasilodon was slow enough to allow strong wear to develop in the teeth.

This replacement slowed down over the individual's lifespan and ceased long before the death of an individual. In some cases, the individual's tooth wore down over time to less than half the height of the crown still remaining. Brasilodontids postcanine replacement occurs the same way as many other advanced Probainognathians, differs from most mammaliforms in the direction of tooth replacement; this is most due to their unlimited skull growth. Tooth replacement variation can also be attributed to cynodont diet. Herbivorous/omnivorous traversodontids species present widened postcanines and tooth replacement is sequential. Carnivores and Insectivores non-mammaliaform probainognathians like Brasilodon present alternating tooth replacement instead. Brasilodon can be seen as more derived than Morganucodon, a close mammal relative, due to its upper and lower symmetrical dentition pattern; the genus Brasilodon belongs to the family Brasilodontidae along with Brasilitherium, Minicynodon and Protheriodon.

Because of the skull and dentition traits seen in Brasilodon, this genus appears to be more derived than any known cynodont, therefore more related to mammals than either tritheledontids or tritylodontids. Since Brasilodontidae exhibits more derived features and many strong differences than other cynodonts, it has been considered that this family is connected with the origin of mammals, although it is younger than the oldest mammals. Despite presenting apomorphies in the skull and dentition, Brasilidontids' postcanines share many synapomorphies with primitive mammaliaformes; this includes a tongue, a system in middle postcanines for mesiodistal interlocking between teeth, similar size and distribution of tooth cusps, a close pattern of wear facets in postcanines, a root with an eight-shaped cross-section. This shows that mammalian tooth replacement evolved after many craniodental features in cynodont evolution. Using C. T. scans of Brasilodon quadrangularis and Didelphis, an extant mammal with primitive cranial morphology, the nasal cavity of Brasilodon and other cynodonts has been shown to be close to mammalian forms.

This indicates that some cynodonts had high respiratory rates and therefore endothermic metabolic status as seen in eucynodonts. Therefore, all of the adaptations needed for endothermy