Kinetic and economic analysis of reactive capture of dilute carbon dioxide with Grignard reagents.

Carbon Dioxide Utilisation (CDU) processes face significant challenges, especially in the energetic cost of carbon capture from flue gas and the uphill energy gradient for CO2 reduction. Both of these stumbling blocks can be addressed by using alkaline earth metal compounds, such as Grignard reagents, as sacrificial capture agents. We have investigated the performance of these reagents in their ability to both capture and activate CO2 directly from dried flue gas (essentially avoiding the costly capture process entirely) at room temperature and ambient pressures with high yield and selectivity. Naturally, to make the process sustainable, these reagents must then be recycled and regenerated. This would potentially be carried out using existing industrial processes and renewable electricity. This offers the possibility of creating a closed loop system whereby alcohols and certain hydrocarbons may be carboxylated with CO2 and renewable electricity to create higher-value products containing captured carbon. A preliminary Techno-Economic Analysis (TEA) of an example looped process has been carried out to identify the electrical and raw material supply demands and hence determine production costs. These have compared broadly favourably with existing market values.

External anterior abdominal wall and pelvic hernias with emphasis on the key diagnostic features on MDCT.

Clinical diagnosis of abdominal wall hernias can be challenging. These common entities can be symptomatic and prone to complications. Pre-surgical planning and investigation of acute presentations can be achieved by multidetector computed tomography (MDCT) with its added multiplanar reformatting capability. Here we delineate the important anatomical landmarks and key signs on CT of a wide spectrum of external anterior abdominal wall and pelvic hernias.

Delivery of safe and effective care out of hours: the impact of the shared clinical record on a patient's out-of-hours contact with specialist palliative care.

Access to adequate clinical information is essential for out-of-hours palliative care teams and general practitioners, specific examples to illustrate and justify this need are surprisingly rare in the medical literature. Without access to the full clinical background the patient in this lesson may have been inappropriately admitted to a palliative care unit and delayed investigations would have misguided the admitting doctor's assessment, planned investigations and management.

Allozyme variation in bumble bees (Hymenoptera: Apidae).

Allozyme variation at an average of 37.3 loci was assessed in queens of 16 Bombus and 2 Psithyrus bumble bee species from North America. The mean expected heterozygosity (H) for the Bombus species was 0.008 +/- 0.006 (95% confidence limits) and that for the Psithyrus was 0.007 +/- 0.007. These levels are significantly lower than found in other Hymenoptera but are comparable to those found in previous studies of bumble bees based on far fewer loci. Neutral mutation and random genetic drift can account for the observed variation, but this implies a very small effective population size for species of bumble bees.

Heart failure in the elderly.

Heart failure commonly occurs in the elderly age group. Treatment mainly centres on the use of digoxin and diuretics. In intractable heart failure other agents ie inotropic agents and vasodilators may be considered. Routine maintenance on diuretic and digoxin should not be encouraged. A conscious effort to tail off these medication is needed.

Management of stroke in the elderly.

Stroke management involves prevention, management of the acute stroke and rehabilitation. Hypertension is probably the most important controllable risk factor in stroke, both ischaemic and haemorrhagic. In the acute stroke, there is as yet no effective medical treatment. Care in the acute phase is mainly supportive with attention to airways, feeding, skin, bowel and bladder care. Rehabilitation aims to maximise the patient's natural recovery and to help him adapt to any residual disability. It involves a multidisciplinary team approach. An accurate and comprehensive assessment of the patient is important to enable the team to set realistic goals. Goals set usually involve functional end-points. The type of community and home support available will influence decision of whether patient could be discharged home. Ideally a patient should be rehabilitated back into his community and support of carers is important if they are to continue with their caring role.

The role of community health care team in the care of the elderly.

The Community Health Care Team plays an important role in helping the elderly maintain an independent life in the community for as long as possible. It does this by emphasizing preventive Geriatric Medicine, provision of supportive and care services and ensuring emotional and physical support for carers. Each member of the Community Health Care team plays an important role and works together as a team to ensure that appropriate services are provided for the varied needs of the elderly in the Community. In Singapore, Community Health Services for the elderly are provided mainly by the Home Nursing Foundation (HNF). Services available at the moment include domiciliary nursing service, rehabilitation and day care carried out at the Senior Citizen's Health Care Centres and Home rehabilitation programme undertaken by trained Staff Nurses. Close liaison is maintained with the Geriatric Department in Tan Tock Seng Hospital. Support groups in existence include a Stroke Club and a Carer's group. Respite care is presently provided by certain voluntary Homes on an ad-hoc basis. The aim of effective community based care for the elderly should be adequate provision of services followed by the effective use of resources.

Hypertension in the elderly.

Hypertension is a common finding in the elderly. Appropriate treatment would reduce the incidence of strokes and cardiovascular events. Caution is however indicated in the selection of whom to treat and how treatment is carried out. Treatment should be initiated only if advantages outweigh disadvantages for that individual patient. Treatment has to be tailored to the individual patient.

Drugs and the elderly.

Prescribing for the older individual requires a great deal of thought. Multiple pathology is usually associated with multiple drug taking and therefore a high risk of adverse drug reactions. Physiological changes have important bearing on drug usage. Constant vigilance is required to ensure safe prescribing.

Parkinson's disease.

The management of the elderly patient with idiopathic Parkinson's disease requires great attention to detail. Treatment should only be considered when the daily activities of life are affected. Medication should be commenced cautiously. Regular review is essential and co-ordination with other members of the multidisciplinary team is vital.

Infections in the elderly.

Infections are a leading cause of morbidity and mortality in the elderly. Altered host defences, a senescent immune system, chronic illnesses, and environmental factors all contribute to the aged's predisposition to infection. Infections can present in atypical fashion contributing to diagnostic and therapeutic delays. Awareness of altered antibiotic absorption, metabolism, and excretion in the elderly is essential to correct antibiotic selection and dosing. Additionally, antibiotic interactions with medications commonly used to treat chronic illnesses should be taken into consideration prior to antibiotic prescribing. Prevention of infectious complications in the elderly requires interest, education, vaccination, and early intervention.

The physiology of ageing.

Normal ageing is responsible for the finite life-span of the human race. It is important for the doctor treating the elderly to know the difference between changes secondary to normal ageing and changes which occur as a result of disease. There is ongoing research to increase our knowledge on the ageing process. Age-related physiological decline results in defective homeostasis responsible for the susceptibility of the individual to succumb in minor stresses. Knowledge of physiological decline in the various organs has clinical implications in the interpretation of physiological tests, especially when the organ systems are stressed, in the need to adjust dosage of drugs given to the elderly and in the understanding of some atypical presentations of illness in the elderly.

Urinary incontinence in the elderly.

Urinary incontinence is a problem affecting a significant proportion of the elderly population. It has substantial medical, psychological, social and economic implications. It is to be regarded as a symptom with multifactorial causes. A useful clinical classification of urinary incontinence is by its pathophysiology. A summary of clinical approach, specified investigations and management principles for the condition is outlined.

Faecal incontinence in the elderly.

Faecal incontinence is distressing both to the patient and the carers. However with accurate diagnosis of its cause, the condition can often be treated. Causes can be classified by pathophysiology. The most common cause in the elderly is faecal impaction with overflow incontinence. Other causes include inflammatory conditions of the bowel, neurological disorder, functional incontinence and iatrogenic incontinence. Management depends on an accurate diagnosis. A proper bowel and drug history is important. A rectal examination is mandatory, in order not to miss a diagnosis of faecal impaction with overflow incontinence. Specific treatment is directed at the cause.

Assessment of an elderly patient.

A complete and comprehensive assessment is the first step towards rational management of the elderly patient. The traditional approach of direct response to specific complaints is inadequate. Systemic enquiries for unstated treatable complaints is essential. A full assessment consists of physical diagnosis, mental assessment, functional assessment and social assessment.

Acute confusion in the elderly.

Acute confusion is common in the elderly ill patient. Its presence should provoke an urgent search for its cause. The key to management of acute confusion is in the removal or reversal of the factors responsible together with good nursing care.

Falls.

An elderly person experiencing recurrent falls is at risk. He is at risk from injury sustained during the fall and at risk from the complications of immobility resulting from loss of confidence. Urgent early assessment and identification of causative and risk factors is essential.

Geriatric medicine: the multidisciplinary approach.

Care of the elderly requires a team approach. Effective teamwork requires adequate communication. Each professional has an important role to play. The patient and carer should also be seen as part of the team and involved in management planning.

Singapore--an ageing society.

Singapore is undergoing a rapid transition into an ageing society. This is due to a dramatic fall in the birth rate combining with a fall in infant and early childhood mortality rate as well as an improvement in the life expectancy. Other changes in the society such as the breaking up of the extended family structure, the changing role of women as well as the increasing expectations of elderly and their families are taking place at the same time. These changes will place increasing demands on the families of the elderly, social services, community and health services. There will have to be a rethinking on how we care for our elderly and the measuring required in meeting this challenge.