A setup to measure the temperature-dependent heating power of magnetically heated nanoparticles up to high temperature.

Magnetic heating, namely, the use of heat released by magnetic nanoparticles (MNPs) excited with a high-frequency magnetic field, has so far been mainly used for biological applications. More recently, it has been shown that this heat can be used to catalyze chemical reactions, some of them occurring at temperatures up to 700 °C. The full exploitation of MNP heating properties requires the knowledge of the temperature dependence of their heating power up to high temperatures. Here, a setup to perform such measurements is described based on the use of a pyrometer for high-temperature measurements and on a protocol based on the acquisition of cooling curves, which allows us to take into account calorimeter losses. We demonstrate that the setup permits to perform measurements under a controlled atmosphere on solid state samples up to 550 °C. It should in principle be able to perform measurements up to 900 °C. The method, uncertainties, and possible artifacts are described and analyzed in detail. The influence on losses of putting under vacuum different parts of the calorimeter is measured. To illustrate the setup possibilities, the temperature dependence of heating power is measured on four samples displaying very different behaviors. Their heating power increases or decreases with temperature, displaying temperature sensibilities ranging from -2.5 to +4.4% K-1. This setup is useful to characterize the MNPs for magnetically heated catalysis applications and to produce data that will be used to test models permitting to predict the temperature dependence of MNP heating power.

Prevalence of depression in a 12-month consecutive sample of patients with ALS.

There is an impression both in clinical practice and in research literature that patients with amyotrophic lateral sclerosis (ALS) possess 'heroic stoicism with a low frequency of depression'. Reliance on specific interview methods may have contributed to differing estimates of mood disorder in people with ALS. The objective of the current study was to compare prevalence rates of depression and anxiety in ALS using different assessment tools. The Beck Depression Inventory (BDI), The Hospital Anxiety and Depression Scale (HADS) and the Spielberger State-Trait Anxiety Inventory (STAI) were sent to a 12-month consecutive sample of 190 patients with ALS attending a tertiary referral clinic in the UK. Data were collected from 104 patients with ALS. Using BDI scores, 44% were categorized as not depressed, 37% were mild-moderately depressed, 13% were moderately-severely depressed, and 6% were severely depressed. In contrast, the HADS depression subscale identified 75% as not depressed, 13% were in the borderline range, and 13% were categorized as meeting 'caseness' for depression. Twenty-five percent of the patients were using antidepressant medication. The estimated prevalence of mood disorder amongst patients with ALS may vary significantly depending on the measure used.

[Cytomorphologic criteria of bronchioloalveolar cell cancer]. / Zytomorphologische Kriterien des Bronchioloalveolarzellkarzinoms.

Cytological material obtained from 100 patients with histologically proven bronchiolo-alveolar cell carcinoma was evaluated on the basis of 27 criteria. Particular features observed were a monocytoid nuclear delimitation (98.4%), central position of the nucleus (90.2%), light-coloured nuclear sap (52.5%), double-nucleation (98.4%), multinucleation (72.1%), phagocytosis (55.7%). Of the features of the accompanying reaction, psuedoproteinosis (9.8%), the presence of hyperplastic pneumocytes II (75.4%) and psammoma bodies (1.6%) are worthy of mention.

AIDS in the workplace: what can be done?

Employers must face the fact that some of their employees may eventually develop AIDS. Yet many organizations still have not developed a comprehensive policy that addresses the issues of educating the workforce about this disease, testing for the virus, and pressuring insurance carriers to change their policies to allow more cost-effective forms of care for people who have AIDS.

The troubled employee. Employee assistance programs.

Cost/benefit aspects of EAPs are elucidated as well as program development and evaluation. Various EAP models are described and future directions of EAPs are postulated.

Employee counseling services evaluation system: design, issues and conclusions.

Employee Counseling Services (ECS) programs have emerged as an effective method for dealing with employees whose job performance has deteriorated due to personal problems such as alcoholism or drug abuse. It is estimated that 18% of any work force is effected by such problems at any given time and that these employees cost industry billions of dollars annually in lost productivity, abuse of sick leave, etc. One of the critical concerns of this emerging field is the need for comprehensive evaluation that can demonstrate the cost-effectiveness and cost-benefits of ECS programs. This paper will describe the model Federal ECS developed at the U.S. Department of Health and Human Services as well as the components of the evaluation system designed to determine its effectiveness. The system is the first of its kind and will be a valuable contribution to the field. The paper then raises issues and develops conclusions about designing such an evaluation within the context of a large bureaucracy.

Combating alcoholism in the workplace.

This article describes occupational assistance-employee assistance programs, which are designed to combat alcoholism in industry. The author, who administers various types of programs, describes the history, conceptual framework, and essential ingredients of a successful program. Relevant legislation, as well as implications for social work, is discussed.

Transport of vitamin B12 in Escherichia coli: common receptor sites for vitamin B12 and the E colicins on the outer membrane of the cell envelope.

The first step in the transport of cyanocobalamin (CN-B(12)) by cells of Escherichia coli was shown previously to consist of binding of the B(12) to specific receptor sites located on the outer membrane of the cell envelope. In this paper, evidence is presented that these B(12) receptor sites also function as the receptors for the E colicins, and that there is competition between B(12) and the E colicins for occupancy of these sites. The cell strains used were E. coli KBT001, a methionine/B(12) auxotroph, and B(12) transport mutants derived from strain KBT001. Colicins E1 and E3 inhibited binding of B(12) to the outer membrane B(12) receptor sites, and CN-B(12) protected cells against these colicins. Half-maximal protection was given by CN-B(12) concentrations in the range of 1 to 6 nM, depending upon the colicin concentration used. Colicin E1 competitively inhibited the binding of (57)Co-labeled CN-B(12) to isolated outer membrane particles. Functional colicin E receptor sites were found in cell envelopes from cells of only those strains that possessed intact B(12) receptors. Colicin K did not inhibit the binding of B(12) to the outer membrane receptor sites, and no evidence was found for any identity between the B(12) and colicin K receptors. However, both colicin K and colicin E1 inhibited the secondary phase of B(12) transport, which is believed to consist of the energy-coupled movement of B(12) across the inner membrane.