Patterns of avian haemosporidia in birds within the greater Cape Town area

Includes bibliographical references.Every species of bird has at least one species of endoparasite or ectoparasite, if not several. Thus it cannot be taken for granted that a particular individual avian species is free from haemosporidian infections. Birds have the richest diversity of intracellular, single cell, protozoan parasites with complicated life cycles, changing between the vector as definitive host (blood-feeding arthropod) and bird as intermediate host. Avian haemosporidian parasites belong to the order Haemospororida, to which the families Haemoprotidae, Plasmodiidae, Garniidae and Leucocytozoidae belong, consisting of the genera Haemoproteus, Plasmodium, Fallisia and Leucocytozoon

Spontaneous-Desorption Ionizer for a TOF-MS

A time-of-flight mass spectrometer (TOF-MS) like the one mentioned in the immediately preceding article has been retrofitted with an ionizer based on a surface spontaneous-desorption process. This ionizer includes an electron multiplier in the form of a microchannel plate (MCP). Relative to an ionizer based on a hot-filament electron source, this ionizer offers advantages of less power consumption and greater mechanical ruggedness. The current density and stability characteristics of the electron emission of this ionizer are similar to those of a filament-based ionizer. In tests of various versions of this ionizer in the TOF-MS, electron currents up to 100 nA were registered. Currents of microamperes or more - great enough to satisfy requirements in most TOFMS applications - could be obtained by use of MCPs different from those used in the tests, albeit at the cost of greater bulk. One drawback of this ionizer is that the gain of the MCP decreases as a function of the charge extracted thus far; the total charge that can be extracted over the operational lifetime is about 1 coulomb. An MCP in the ion-detector portion of the TOF-MS is subject to the same limitation

Mobility impairment in the elderly: Challenges for biomechanics research

The problems of mobility impairment in the elderly constitute new and major challenges for biomechanics research. This paper outlines what some of the important problems are, discusses the relevance of biomechanics research to these problems, and reviews some of the current state of knowledge about factors related to the biomechanics of mobility impairments in the elderly. The population of old adults is growing rapidly and the incidence of mobility impairments in old adults is high. Mobility impairment biomechanics research is needed to make the assessments of impairments more precise, to design therapeutic programs that are more effective and to learn more about how mobility impairments can be prevented.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30086/1/0000457.pd

Introduction

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43992/1/10439_2006_Article_BF02371447.pd

Child and adolescent suicide: A perspective for the elementary school guidance counselor

The elementary school guidance counselor is in a unique position to assist in the identification of young people who are at-risk or potential suicide casualties. The counselor can enhance this identification by alerting the school population (administrators, teachers, staff, and students) to the dynamics of suicide among young people (Deykin, 1984). Suicide implies a total turning away from life itself showing the inability or refusal to accept the terms of human development, both physically and emotionally (Maris, 1981 ). The elementary counselor must be aware of suicide not only from its tragic consequences but from the standpoint of positive prevention. The counselor needs to increase his/her knowledge of suicide including current statistical information, suicide myths, suicide antecedents, intervention strategies, and prevention strategies

Do Neural Factors Underlie Age Differences in Rapid Ankle Torque Development?

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111232/1/j.1532-5415.1996.tb03737.x.pd

Biomechanics of reactions to impending falls

Responses of 11 young adult males, initially standing, to support surface forward accelerations of 0.18 g were investigated. In response to the impending falls this stimulus initiated, body segment motions and myoelectric activities in six muscles were measured. These measurements were then input to 9 or 12 segment whole body biomechanical models and the reaction joint torques needed to produce the motions were calculated.Mean relative joint rotations were as large as 92.8[deg] and calculated relative joint angular accelerations as large as 29.7 rad s-2. Mean myoelectric signal latencies in the six muscles monitored ranged from 135 ms at the ankles to 176 ms at the shoulders with intermediate values at intermediate joints. Mean values of calculated maximum joint torques ranged to 70 Nm at the ankles, 82 Nm at the knees, 73 Nm at the hips, and 19 Nm at the shoulders.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27580/1/0000624.pd

Drinfeld Twists and Symmetric Bethe Vectors of Supersymmetric Fermion Models

We construct the Drinfeld twists (factorizing $F$-matrices) of the $gl(m|n)$-invariant fermion model. Completely symmetric representation of the pseudo-particle creation operators of the model are obtained in the basis provided by the $F$-matrix (the $F$-basis). We resolve the hierarchy of the nested Bethe vectors in the $F$-basis for the $gl(m|n)$ supersymmetric model.Comment: Latex File, 24 pages, no figure, some misprints are correcte