Multi-element analysis of South African wines by ICP-MS and their classification according to geographical origin.

Wines from three important wine-producing regions, Stellenbosch, Robertson, and Swartland, in the Western Cape Province of South Africa, were analyzed by ICP-MS and the elemental composition used in multivariate statistical analysis to classify the wines according to geographical origin. The method is based on the assumption that the provenance soil is an important contributor to the trace element composition of a wine. A total of 40 elements were determined in 40 wines.

HIV/AIDS and the workplace: perceptions of nurses in a public hospital in South Africa.

Aim: The purpose of this article is to report a study of the perceptions and experiences of nurses caring for people living with HIV/AIDS in the public health sector in South Africa.

Background: The number of people living with HIV/AIDS in South Africa has escalated at an alarming rate. Many people being hospitalized are HIV positive, and hence nurses are in more regular and prolonged contact with people suffering from HIV/AIDS than is the case in other working environments.

Strategies to overcome obstacles in the facilitation of critical thinking in nursing education.

Unlabelled: This paper seeks to describe strategies that can be used to overcome obstacles in the facilitation of critical thinking in nursing education. A qualitative, explorative, descriptive and contextual design was used to conduct the research in which fourth year basic comprehensive students and nurse educators volunteered to take part in the study by signing an informed consent. The participants were purposively selected.

Redescription of Argulus multipocula Barnard, 1955 (Crustacea: Branchiura) collected on the west coast of South Africa.

Argulus multipocula Barnard, 1955 was originally described from a single female found in a littoral sample from the east coast of South Africa. We present a redescription of this species based on light and scanning electron microscope studies of 25 females collected from the southern mullet Liza richardsonii (Smith) on the west coast of South Africa.

The managerial duties of the nurse in charge of a unit in combating the spreading of HIV/AIDS.

The charge sister has an essential role to play in combating the spreading of the HIV in the environment of the nursing unit. The HIV/AIDS dilemma is a reality in the health care environment. On a daily basis nurses is treating patients with the HIV.

Evaluation of a synthetic vaccine construct as antigen for the detection of HIV-induced humoral responses.

Synthetic V3 loop peptides hold numerous benefits for the development of HIV vaccines and in immunodiagnosis; however, their use is limited due to the extensive antigenic variability of this region. The effectiveness of a potential HIV vaccine component, which accounts for V3 loop variability, is evaluated here. A branched peptide construct representing multiple sequences and allowing 1.

A model to facilitate reflective thinking in clinical nursing education.

A qualitative, contextual, exploratory and descriptive design for theory generation was used to develop a model to facilitate reflective thinking in clinical nursing education (Mouton & Marais, 1990:43; Mouton, 1996: 103-109; Chinn & Kramer 1991:79-120). A model was developed within the existing frameworks of theory generation. Wilson (1963:23-39) and Gift (1997:75,76) provided a theoretical framework for a concept analysis of reflective thinking in phase one of the study.

Reflective thinking in clinical nursing education: a concept analysis.

Over decades nursing had an interest in clarifying and developing its knowledge base and its conceptual foundation. Reflective thinking has become a popular word in nursing education world wide, but its meaning and effective use remains debatable because of lack of clarity in its meaning (Mackintosh, 1998:553). The researcher engaged in the concept analysis of reflective thinking so as to fully understand its meaning and interpretation, hence the research question to be addressed by this article is: "What is the meaning of reflective thinking in clinical nursing education?" This article seeks to explore and describe the conceptual meaning of reflective thinking in clinical nursing education using the method of concept analysis as outlined by Wilson (1963:23-39) and Gift (1997:75,76).

An improvement on the power law for the description of particle size distributions in potable water treatment.

In potable water treatment, the use of the power law to describe particle size distributions (PSDs) in particle counting practice is common. The power law is popular because it allows the reduction of numerous data bits to two meaningful parameters that completely describe the size distribution characteristics of a particle suspension. The model is however flawed.

Peptide immunogens designed to enhance immune responses against human immunodeficiency virus (HIV) mutant strains: a plausible means of preventing viral persistence.

A major problem impeding the development of an effective HIV-1 vaccine is the rapid antigenic variability that occurs throughout the viral genome but is most pronounced in the envelope (env) gene and env gene products. The high number of errors made by the reverse transcriptase (RT) enzyme and the absence of an RT proofreading mechanism during HIV-1 replication leads to new antigenic variants that escape current immunological attack. In turn, accumulation of escape mutants leads to a persistent infection.

The curious life-style of the parasitic stages of Gnathiid isopods.

Isopods of the family Gnathiidae have free-living adults and parasitic juveniles feeding on the blood and tissue fluids of teleost and elasmobranch fishes. When not feeding on fishes, gnathiids are cryptic and widely distributed, especially among marine habitats. Ten genera are recognized: Bathygnathia, Bythognathia, Caecognathia, Elaphognathia, Euneognathia, Gibbagnathia, Gnathia, Monodgnathia, Paragnathia and Thaumastognathia.

Proper and improper stigmatic optical systems.

Stigmatic optical systems are of two classes: proper and improper stigmatic systems. The purpose of the article is to explore the nature of the two classes. The image may be rotated in the case of proper stigmatic systems and is reflected in a line in the image plane in improper stigmatic systems.

Stigmatic optical systems.

There would appear to be little disagreement on what constitutes an astigmatic system in the case of a thin lens: the cylinder is not zero. A spherical thin lens is stigmatic or not astigmatic. The issue is less clear in the case of a thick system.

The effect of iron overload on in vitro HIV-1 infection.

Background: It has been shown that Fe is required by HIV-infected cells for production of viral particles. Excess iron in the cell is detrimental to the host but beneficial to the pathogen.

Objectives: Here, we investigated the effect of excess Fe (overload) and chelation of the metal on in vitro HIV infection by assessing host cell responses (viability/death, stress protein expression and cytokine production) as well as virus replication (core protein content and enzyme activity).

Limited cross-reactivity between different HIV-1 clades.

Background: The past two decades has seen an extensive search for a vaccine to curtail the HIV/AIDS pandemic. The prevailing opinion is that an HIV vaccine should elicit broadly cross-neutralizing antibodies and cellular immune responses against primary isolates from divergent clades. The majority of subunit or protein based vaccines currently in clinical trials are based on HIV-1 envelope proteins mainly derived from subtypes B/A.

Realizability of optical systems of given linear optical character.

The linear optical character of an optical system is represented by a particular type of 5 x 5 matrix. This article shows that the converse is also true, namely, that an optical system can be constructed in principle with linear optical character represented by any matrix of this type. In other words, every matrix of this type is realizable as an optical system.

The average eye.

For statistical and other purposes one needs to be able to determine an average eye. An average of refractive errors is readily calculated as an average of dioptric power matrices. A refractive error, however, is not so much a property of the eye as a property of the compensating lens in front of the eye.

Salicylic acid-mediated potentiation of Hsp70 induction correlates with reduced apoptosis in tobacco protoplasts.

Background: Elevated temperatures jeopardize plant disease resistance, as mediated by salicylic acid (SA). SA potentiates heat-induced expression of the 70-kDa heat shock protein (Hsp70) in tomato cells. In mammalian cells, Hsp70 suppresses apoptosis.

The use of different enzymes in feral freshwater fish as a tool for the assessment of water pollution in South Africa.

Selected enzymes in the organs/tissues of two fish species (Oreochromis mossambicus and Labeo umbratus) were evaluated as biomarkers of water pollution in warm- and cold-water systems. The fish were caught using standard techniques during two high-flow and two low-flow surveys. The results indicated that the fluctuating enzyme activities measured were not a result of pollution but could be initiated as a result of (1) no or too little pollution, (2) handling of the fish, and (3) struggling in the nets.

Synthesis, crystal structure and hydroformylation activity of triphenylphosphite modified cobalt catalysts.

The dinuclear complex [Co(2)(CO)(6)[P(OPh)3]2] (2) has been synthesised and was fully characterised. The solid state structure revealed a trans diaxial geometry, no bridging carbonyls, and Co-Co and Co-P bond lengths of 2.6722(4) and 2.

Carbonyl(5-nitrotropolonato-kappa2O1,O2)(triphenylphosphine-kappaP)rhodium(I).

The molecule of the title complex, [Rh(5-NO2trop)(C18H15P)(CO)] (5-NO2trop is 2-hydroxy-5-nitrocyclohepta-2,4,6-trienone, C7H4NO4), has a distorted square-planar geometry. Strong intramolecular and weak intermolecular hydrogen bonding is observed, with H..

[2-(Anilinomethyl)phenyl]diphenylphosphine and [2-[(N-methylanilino)methyl]phenyl]diphenylphosphine.

The title compounds, Ph(2)PCH(2)N(H)Ph or C(25)H(22)NP and Ph(2)PCH(2)N(CH(3))Ph or C(26)H(24)NP, respectively, are isomorphous, with calculated theoretical Tolman angles of 174 and 182 degrees.

cis-Diphenylbis(1,3,5-triaza-7-phosphaadamantane-kappaP)platinum(II).

The structure of the title compound, [Pt(C(6)H(5))(2)(C(6)H(12)N(3)P)(2)] or [Pt(Ph)(2)(PTA)(2)] (where Ph is phenyl and PTA is 1,3,5-triaza-7-phosphaadamantane), is discussed. Selected geometric parameters are: Pt-P = 2.2888 (16) and 2.