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The suitability of 'design' height amplification factors (HAF) for the purpose of seismic assessment of existing non-structural unreinforced masonry (URM) components with known strength was evaluated through a numerical study. Four building typologies were included that represented pre-1940 URM construction in Australia and New Zealand. Through pushover and incremental dynamic analyses, the effects of diaphragm flexibility and nonlinear building response on floor accelerations were studied. It was found that Australia/New Zealand code procedures include significant inelastic building behaviour that reduces HAF. An interpretation was made on the applicability of the assumptions in the context of assessing non-structural URM components. [ABSTRACT FROM AUTHOR]

Out-of-plane fl exural testing of three full-scale unreinforced masonry (URM) walls seismically retrofi tted using post-tensioning is reported. The selected wall confi gurations were representative of common URM walls that were vulnerable to out-of-plane failure, and imitated heritage URM construction by using salvaged clay brick masonry and ASTM type O mortar. Varying levels of pre-compression were applied to the test walls using a single mechanically restrained tendon inserted into a cavity at the centre of each test wall. Three different types of tendons were used for post-tensioning of the test walls, being threaded mild steel bar and sheathed greased seven wire strands (with tensile yield strengths of 1300 and 1675 MPa). Behaviour of the post-tensioned URM walls was compared to the response of a non retrofi tted URM wall, with the out-of-plane fl exural strength of the post-tensioned masonry walls observed to range from 2.9 to 10.3 times the strength of the non retrofi tted URM wall. Several aspects pertaining to the seismic behaviour of post-tensioned masonry walls were investigated, including tendon stress variation, damage patterns, force displacement behaviour, initial stiffness and displacement capacity. Test results were compared with equations developed in previous studies, and it was established that the walls that were post-tensioned using seven-wire strands had measured strengths that compared favourably with predicted values, whereas the wall that was post-tensioned using mild steel bar had failed at a lower measured strength than the predicted value. [ABSTRACT FROM AUTHOR]

Seismic performance verification of a spiral thread mechanical reinforcement connection system for use in reinforced concrete structures was investigated by conducting both in-air component tests and structural subassembly tests. Current performance verification criteria listed in NZS 3101:2006 were found to be outdated and, following a review of various international protocols for testing mechanical connection systems, it was concluded that DIS 15835 protocols should instead be considered for adoption. Two external beam-column joint subassemblies having spiral thread mechanical reinforcement couplers installed at the column-joint interface were subjected to simulated seismic cyclic loading. It was found that bar curvature and the development of a non-uniform stress distribution around the perimeter of the reinforcement-coupler connection led to coupler slippage. However, the measured pinched hysteretic response owing to coupler slippage closely matched the response of companion tests where strength degradation was instead a result of excessive beam shear deformations. It was concluded that uniaxial tensile tests are unable accurately to demonstrate probable coupler performance in plastic hinge zones and that such tests should therefore not be used to predict likely ductile response in potential plastic hinge zones of reinforced concrete members. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the guest editorial "Biologic Problems of the Light-Cured Composite Resin," by Takao Fusayama in the April 1993 issue.

Pain among cancer patients is a common distressing symptom that frequently affects physical functioning, social interaction, psychological status, and quality of life. Despite the extensive body of knowledge available regarding cancer pain assessment and management, it often remains untreated, thereby diminishing the quality of patient care at the end of life. Recommendations on how to remove these barriers, as well as to improve care of the dying in general, need to be implemented by the U.S. government.

Medical intervention aims to eliminate disease, to mitigate disease effect, and maximize quality of life. Throughout the course of illness, accurate symptom assessment is imperative if these goals are to be achieved. Symptom scales may facilitate this process in the clinical setting. Many valid scales are available for research, and investigators must be familiar with a methodology that can quantify the impact of therapies on symptoms, symptom distress, and overall QOL.

A case of cardiovascular autonomic insufficiency is described in a cachectic 70-year-old man with widely metastatic small-cell tumor. The patient experienced disabling syncopal episodes in association with severe postural hypotension. Tests of cardiovascular autonomic insufficiency were abnormal. The introduction of fludrocortisone and the use of elastic stockings produced palliation of the symptomatology, but his condition deteriorated and he died. Autopsy demonstrated unexpectedly extensive tumor invasion of autonomic nervous tissue. Although cardiovascular autonomic insufficiency (CAI) has been described in association with malignancy and malnutrition, local tumor invasion of autonomic nervous tissue and radiation injury may have been other possible, albeit unusual, etiologic factors. This case illustrates the differential diagnosis of hypotension and CAI in patients with advanced metastatic malignancy and also emphasizes the need for autopsy studies when speculating as to the cause of CAI in this group of patients.

In this paper traditional medical beliefs and practices in a Mexican village are described and interpreted. The analysis focuses on the notion that health is a balance of hot and cold within the body. Several lines of evidence are used to reveal the metaphorical meanings of hot and cold, and these meanings are then seen to be related to structural features of peasant society.