Nymphs of the western black-legged tick, Ixodes pacificus, were found on the trunks of trees during spring and summer in northwestern California. In a woodland-grass habitat, large- and medium-sized (> 130 cm and 80-130 cm in circumference, respectively), moss-covered oak (Quercus spp.) trees supported ticks significantly more often than trees without these characteristics. Additionally, trees ...

A geometric morphometrics approach was applied to evaluate differences in forewing patterns of the Jandaira bee (Melipona subnitida Ducke). For this, we studied the presence of fluctuating asymmetry (FA) in forewing shape and size of colonies kept in either rational hive boxes or natural tree trunks. We detected significant FA for wing size as well as wing shape independent of the type of housi...

DURING the past several years the existence of thromboangiitis obliterans as a distinctive disease entity has been seriously questioned. This evidently began with the suggestion by Fisher' that the peripheral manifestations of so-called Buerger's disease might actually represent atherosclerosis of the large arterial trunks with distal thrombosis. A more comprehensive study by Wessler et al.2 ap...

The myocardial fibres of the posterior wall of the atrio-venous junctions were examined in 35 large domestic mammals. In the majority of specimens a common pattern in the course and organization of the fibres could be observed. The most obvious features were the following: (1) a main circular fascicle surrounding the pulmonary trunks; (2) fibres encircling the atriovenous junctions; and (3) myo...

Branching pattern of middle cerebral artery influences frequency of its aneurysms, and is of potential value in their surgical repair and diagnosis of stroke. This pattern shows inter-population variations but there is paucity of data from Africans. This study aimed at describing branching pattern among black Kenyans. Middle cerebral arteries numbering 288 from 144 formalin fixed brains obtaine...

Introduction The brachial plexus is a complex network of nerves extending from the neck to axilla supplying motor sensory and sympathetic fibers to the upper extremity and superficial muscles of the back. It is formed by the fusion of the anterior primary rami of the C5, C6, C7, C8, and T1 spinal nerves, with occasional communications from C4 and T2 making it either pre-fixed or post-fixed, res...

The axial skeleton of all vertebrates is composed individual units known as vertebrae. Each vertebra has anatomical attributes, yet they can be classified in five different groups, namely cervical, thoracic, lumbar, sacral and caudal, according to shared characteristics their association with specific body areas. Variations vertebral number, size, morphological features distribution amongst the...

Aneurysmal diseases are often silent but can cause potentially life-threatening complications in cases of dissection or rupture. Surgical strategies depend on the involved part of the aorta and frequently require extracorporeal circulation and circulatory arrest. From data available from the Centers for Disease Control and Prevention, aneurysm disease is the 18th most common cause of death in a...