Evaluating glycine as an alternative lixiviant for copper recovery from waste printed circuit boards.

Current hydrometallurgical processing routes for copper recovery from waste printed circuit boards (PCBs) utilise strong mineral acids, which pose environmental hazards. Glycine has been proposed as an alternate lixiviant with a lower environmental impact. This study aimed to investigate the effectiveness of glycine as lixiviant for copper dissolution from waste PCBs. Bench scale laboratory leaching tests were performed to investigate the effect of key process variables such as temperature, oxidant type and lixiviant concentration on the rate, extent and selectivity of copper leaching. In the presence of oxygen as oxidant, the glycine concentration did not have a significant effect on the rate or extent of copper leaching in the range 1 M to 2 M. Increasing the temperature from 25 °C to 60 °C increased copper dissolution after 22 h from 29.6% to 81.2% when using a glycine concentration of 1 M. When air instead of oxygen was used as oxidant, the copper dissolution achieved with 1 M glycine after 22 h at 60 °C decreased by 43.9 percentage points to 37.3%, due to the lower concentration of dissolved oxygen in the system. Using hydrogen peroxide instead of oxygen as oxidant, did not improve the overall extent of copper leaching achieved. Leaching with 1 M glycine and oxygen as oxidant at 60 °C is proposed as the most feasible operating conditions within the ranges investigated, because these conditions yielded the highest copper dissolution (81.2%) with relatively low (1.3%) gold co-extraction.

PTEN mutations in uterine sarcomas.

OBJECTIVE: Uterinesarcomas comprise three main types: carcinosarcomas, leiomyosarcomas, and endometrial stromal sarcomas. Carcinosarcomas are highly aggressive neoplasms with a biphasic histology of carcinomatous and sarcomatous elements. It is now generally accepted that carcinosarcomas are biphasic tumors that have to be regarded as endometrial carcinomas where metaplasia occurs. Mutations of the PTEN tumor suppressor gene, located on 10q23, play a significant role in the pathogenesis of the endometrioid type of endometrial carcinoma. Loss of heterozygosity of chromosome 10q has been reported in uterine leiomyosarcoma. Since little is known about the molecular pathobiology, our goal was to investigate the potential role of the PTEN gene in the carcinogenesis of uterine sarcomas. METHODS: We examined 21 carcinosarcomas, 21 leiomyosarcomas, and 5 endometrial stromal sarcomas using exon-by-exon polymerase chain reaction-single-strand conformation polymorphism analysis. RESULTS: Overall 8.5% (4/47) of uterine sarcomas were found to harbor somatic PTEN mutations. Of these, approximately 17% (3/18) were carcinosarcomas with endometrioid-type carcinoma components and approximately 5% (1/21) were leiomyosarcomas. No mutations were detected in carcinosarcomas with nonendometrioid carcinoma components (0/3) and in endometrial stromal sarcomas (0/5). CONCLUSIONS: These data suggest that intragenic PTEN mutations are involved in the genesis of uterine carcinosarcomas with endometrioid-type carcinoma components but rarely contribute to the pathobiology of uterine leiomyosarcomas.

Ehrlichia ruminantium major antigenic protein gene (map1) variants are not geographically constrained and show no evidence of having evolved under positive selection pressure.

In a search for tools to distinguish antigenic variants of Ehrlichia ruminantium, we sequenced the major antigenic protein genes (map1 genes) of 21 different isolates and found that the sequence polymorphisms were too great to permit the design of probes which could be used as markers for immunogenicity. Phylogenetic comparison of the 21 deduced MAP1 sequences plus another 9 sequences which had been previously published did not reveal any geographic clustering among the isolates. Maximum likelihood analysis of codon and amino acid changes over the phylogeny provided no statistical evidence that the gene is under positive selection pressure, suggesting that it may not be important for the evasion of host immune responses.

Microsatellite instability in uterine sarcomas.

Studies have shown a 15-30% frequency of microsatellite instability in endometrial cancer. In addition, we found a 21% frequency of microsatellite instability in endometrial cancer. Our aim was to investigate the presence of microsatellite instability and loss of heterozygosity in uterine sarcomas. The records of 69 women referred to Kalafong Academic and Pretoria Academic Hospital with a primary diagnosis of uterine sarcoma were reviewed. At histological review of 43 cases with a primary diagnosis of leiomyosarcoma, diagnosis of mitotically active leiomyoma was made in 21. Diagnosis of carcinosarcoma was made in 21 cases and endometrial stromal sarcoma in five. In all cases, genomic DNA was extracted from normal myometrium and tumor and analyzed for microsatellite instability and loss of heterozygosity. High-frequency microsatellite instability was absent in leiomyosarcoma, endometrial stromal sarcoma, and mitotically active leiomyomas and was observed in 1 (5%) carcinosarcoma. Loss of heterozygosity for chromosome 11 was present in 8/48 (17%) of uterine sarcomas, equally distributed between leiomyosarcomas (4/22 = 18%) and carcinosarcomas (4/21 = 19%). There was no loss of alleles in endometrial stromal sarcoma nor mitotically active leiomyomas. In conclusion, it is suggested that tumor suppressor genes may play a role in the tumorigenesis of uterine mesenchymal cells, whereas mismatch repair genes contribute to the carcinogenesis of endometrial cancer.

[Standards for neonatal intensive care nursing: unit directed management standards]. / Standaarde vir neonatale intensiewesorgverpleging: eenheidsbestuursgerigtestandaarde.

The neonate has the right to quality nursing care and the Neonatal Intensive nursing care practitioner is professionally-ethically and personally liable for quality nursing care. The process of quality improvement is a structured, planned and purposeful action were standards are set and the nursing care is evaluated after which remedial steps are taken to improve quality nursing care. In this study the focus is on the first step in the quality assurance cycle:the setting of standards. The purpose of the study is to describe and formulate standards for Neonatal Intensive nursing care which can be utilised as an accreditation instrument for institutional selfevaluation to improve quality nursing care. Standards for Neonatal Intensive nursing care were developed and validated by utilising a three-phase research method. In phase one subjects for standards were identified by a panel of experts. The identification was done by means of a critical debate, after which a preliminary conceptual framework was formulated. During the second phase a literature control was done to refine the conceptual framework. It consisted of a conceptual framework pertaining to unitmanagement (article 1) and an conceptual framework pertaining to high incidency, high risk interactions in the Neonatal Intensive Care Unit. The conceptual framework pertaining to the high incidency, high risk interactions in the Neonatal Intensive Care Unit consisted of: assessment of the neonate preparedness for neonatal resuscitation mechanical ventilation humidification during ventilation physiotherapy and suctioning of the ventilated neonate weaning during mechanical ventilation ecstubation During the third phase, the standards were validated by means of a consencus debate. An accreditation instrument was developed for institutional selfevaluation to improve quality nursing care in the Neonatal Intensive Care Unit. The standards that were formulated consisted of standards for unitmanagement (article 1) and standards directed at high incidency, high risk interactions in the Neonatal Intensive Care Unit which is published in the second article in this series.

[Nurses' and patients' experience of combined health service delivery to all population groups in a hospital]. / Verpleegkundiges en pasiënte se belewenis van gesamentlike gesondheidsdienslewering aan alle bevolkingsgroepe in 'n hospitaal'.

In a community hospital in Gauteng, the hospital management had, on short notice, to provide combined health services to all population groups. In the past different health services were delivered to each population group. The integration of health service delivery was a sudden change. Based on this, research questions arose, namely: how do nurses and patients experience this change, and how could they be assisted to adjust to the change. The research objectives were twofold, namely: to explore and describe nurses and patients' experience of combined health delivery to all population groups and based on the results to make recommendations to assist them with adjustment to a combined health delivery system. An exploratory, descriptive and contextual research design was followed. Trustworthiness was ensured by applying Guba's approach. Phenomenological and individual focus interviews were conducted with forty nurses and patients who were selected purposively. Field notes were written after completion of each interview. The transcribed data was analysed by using Giorgi's and Kerlinger's methods combined. Results were discussed and a literature control completed. The most important conclusions reached were: there was an insufficient administrative structure in the hospital as a result of insufficient preparation for the combined health service delivery for all population groups; the whites' perception of different populations groups is based on an ethnocentric Western approach. This led to their experience of culture shock that resulted in feelings of anger/frustration, fear and sadness; the willingness of other populations groups to adjust to combined health service delivery led to their experience of happiness; there exists communication problems between population groups because of their not being able to communicate in their own language and the difference in communication styles; the verbalised Christian viewpoint and values of whites nurses and patients are not congruent with their prejudiced perception of people of other population groups and cultures, and the different population groups do not know each other's lifeworlds and that leads to prejudices that block open communication. Several recommendations were made based on these conclusions.

The experiences of parents where pregnancy ended in an unplanned caesarean section.

The purpose of this study was to determine the experiences of parents prior to, during and following an unplanned caesarean section. Parents who experienced this event had mixed emotions. The related occurrences may have influenced their behavior and consequently their relationships with their spouses, themselves and their environment. These continually interacted with each other and thus needed to be looked at in context. "The Nursing of the Whole Person Theory" ensured a holistic approach to the parents. Unstructured, in-depth interviews held with five mothers and five fathers, respectively, on day three post-delivery, were transcribed and analysed. At six weeks a follow-up semi-structured questionnaire was answered by these same respondents and analysed. The experiences of the parents were then compared. A literature survey was undertaken in order to determine the conclusion of other researchers in this field, the results of which were compared with those of the present study and conclusions were reached. Recommendations concerning nursing practice, education and further study were made at the end of the study. A list of limitations affecting the study is included.

Noise in a neonatal unit: guidelines for the reduction or prevention of noise.

Advances in medical technology have led to major technological developments in the field of neonatal care. Over the past three decades there has been increasing concern about noise levels in neonatal intensive care units. The experience of working in a neonatal intensive care unit (NICU) and exposure to high noise levels of such a unit prompted the researcher to investigate the sources of noise further and to explore ways of reducing or preventing the occurrence of such noise. The environment of one NICU consisting of a critical care area and a "grower type" nursery was surveyed with the aim of establishing noise levels in such a unit. A GR (General Radio) 1565-B sound level meter was used to measure the noise levels in the NICU and recordings of noise levels were made. Data were entered into the checklist each time a sound level was recorded and later analysed. In the critical care area sound levels ranged from 64-66 dB (A) (A weighted decibel scale) and in the grower nursery from 50-60 dB (A). Recent British and American Standards require that the mean noise levels inside the incubator should not exceed 60 dB (A) which is safe for the adult human ear (Wolke 1987). When compared with the in utero environment the noise levels of the neonatal unit are high and potentially hazardous because of the large numbers of staff and the amount of equipment present. The main findings of the study were that: There is a considerable level of noise in the NICU and this noise persists throughout day and night.(ABSTRACT TRUNCATED AT 250 WORDS)

[Parents' experience of the death of their baby with congenital disorder]. / Ouers se belewenis van die dood van 'n baba met kongenitale afwykings.

The purpose of this study is to determine the experiences of the parents after the death of a congenital abnormal baby. Parents who have lost a baby go through a process of grief. This also applies to parents of a baby with congenital abnormalities. Parents whose congenital abnormal baby dies, not only grieve because of the abnormality of their baby, but also because it died. Unstructured in-depth interviews were held with six couples within a year after the death of their babies. The experiences of the six couples were afterwards compared. A literature study was undertaken in order to determine what the conclusions of other researchers field were. The result of the literature study was compared with that of the present study. Recommendations are made at the end of this study on the practical applications, education and further research that can be undertaken on this subject.

[Maintaining epidural anesthesia by the midwife]. / Die instandhouding van epidurale narkose deur die vroedvrou.

Epidural anaesthesia as a method of pain relief during labour has lately become very popular. Statistics show that in some labour units up to 70 per cent of all patients undergo epidural anaesthesia. The popularity of this method can be attributed to its effectiveness in relieving pain during labour. The anaesthetist commences an epidural block by introducing an epidural catheter into the epidural space. The anaesthetist administers the test dose and the first therapeutic dose. Within a short duration of time (10 to 20 minutes) the patient can already experience the numbing effect of the anaesthetic. This anaesthetic loses its numbing effect within two to three hours and effective pain relief can only be achieved by administering a further dose of local anaesthetic via the epidural catheter. This procedure can be repeated between three to six times during the average duration of labour. Alternatively, a continuous epidural infusion procedure can be used. The last method, however, sometimes requires the administration of additional epidural "top-ups". There are some risks in administering additional "top-up" dosages. The possibility exists of the anaesthetic causing a spinal block as a result of being administered into the spinal fluid. The "top-up" can also cause convulsions if administered intravenously. In some units it is expected of the midwife to maintain epidural anaesthesia on prescription by the doctor. These side-effects can, however, also occur when the patient is being treated by medical personnel with ample experience and knowledge. It is expected of some midwives to maintain an epidural block on prescription by the anaesthetist. If the midwife lacks the necessary knowledge of epidural anaesthetic and its maintenance, she might unintentionally administer the local anaesthetic into the spinal fluid or intravascularly. This might cause a threat to the mother's and baby's lives. This research covers the maintenance of epidural anaesthesia as carried out by the midwife. The level of involvement of the midwife in the maintenance of epidural anaesthesia has been investigated. The midwife's knowledge about the maintenance of epidural anaesthesia, her legal rights, obligations and emergency treatment of patients have been investigated. It has also been considered whether protocols in the maintenance of epidural anaesthesia exist. All the abovementioned information was acquired by submitting a questionnaire for completion by midwives practising in labour wards in the Johannesburg area. The results of this research show that the midwife's knowledge as regards to epidural anaesthesia and its maintenance is inadequate.(ABSTRACT TRUNCATED AT 400 WORDS)