Application of HPLC for the Determination of PSP Toxins in Shellfish

A high performance liquid chromatographic (HPLC) procedure for determination of the toxins associated with paralytic shellfish poisoning (PSP) is compared to the standard AOAC mouse bioassay method on 100 shellfish samples representing a variety of species. For those samples with toxin content below the detection limit of the bioassay (35 μg saxitoxin (STX)/100g) HPLC analysis indicated a similar low level with a range of <10 to 56 μg STX/100g (n = 60). A correlation coefficient of 0.92 was determined for the 40 samples exhibiting toxicity in the bioassay (i.e., >35 μg STX/100g). Among the advantages of the HPLC method over the bioassay are significantly better sensitivity, greater sample through-put, and ability to determine the levels of each individual PSP toxin.     

Phase Relations and Ordering in the Systems MgO-Y2O3-ZrO2 and CaO-MgO-ZrO2

The phase relations in the systems MgO-Y₂O₃-ZrO₂ and CaO-MgO-ZrO₂ were established at 1220° and 1420°C. The system MgO-Y₂O₃-ZrO₂ possesses a much-larger cubic ZrO₂ solid solution phase field than the system CaO-MgO-ZrO₂ at both temperatures. The ordered δ phase (Zr₃Y₄O₁₂) was found to be stable in the system ZrO₂-Y₂O₃ at 1220°C. Two ordered phases φ₁ (CaZr₄O₉) and φ₂ (Ca₆Zr₁₉O₄₄) were stable at 1220°C in the system ZrO₂-CaO. At 1420°C no ordered phase appears in either system, in agreement with the previously determined temperature limits of the stability for the δ, φ₁, and φ₂ phases. The existence of the compound Mg₃Y_zO₆ could not be confirmed.     

TOWARD AN ARRAY OF PHENOMENOLOGICAL IDEAL-TYPES FOR THE SOCIAL SCIENCES

Beginning with the isolation of four essentially unique mathematical intervals on a continuum, we show the process by which an array of four phenomenological ideal-types can be generated which carry rather specific analytical and administrative implications. The basic vehicle of the paper is deductive inference, employed to generate successively more specific taxonomies of system types, eventuating in the four felt to be a specific interest as real-world references for the social scientist, with empirical point included wherever they can defend the deductions.     

Retrodiction as a tool for micromaser field measurements

We use retrodictive quantum theory to describe cavity field measurements by successive atomic detections in the micromaser. We calculate the state of the micromaser cavity field prior to detection of sequences of atoms in either the excited or ground state, for atoms that are initially prepared in the excited state. This provides the POM elements, which describe such sequences of measurements.     

THE LIMITS AND POTENTIAL OF NONPROFIT ORGANIZATIONS IN PARTICIPATORY PLANNING: A CASE STUDY OF THE NEW YORK HIV PLANNING COUNCIL

ABSTRACT: In addition to providing a wide range of essential services in local communities, service‐providing nonprofit organizations play an important role in shaping de facto local social policy through their participation in community‐based planning processes that guide or determine the distribution of federal funding for health and social services. This social policy role has become increasingly important in the United States as the federal government continues to privatize health and human services through providing grant funds to states and cities that are ultimately used to support local nonprofit health and social service organizations. The important role of service‐providing nonprofits in shaping local social policy has been understudied, as most studies on nonprofits and policy‐making focus on citizen advocacy organizations and their lobbying and protest activities, primarily at the national level. This study uses the case of the New York HIV Planning Council to address this gap in the literature, highlighting the benefits and pitfalls of an urban community planning process dominated by service providers from local nonprofit social service organizations whose own organizations are affected by the planning group's decisions. Factors that contributed to nonprofit providers' dominance as well as factors that limited their self‐interested behavior are reviewed. The relationship between the HIV nonprofit service system and the AIDS social movement is explored in light of theory on new social movements to help explain why nonprofit providers were sometimes able to promote attentiveness to the general public good while also advocating for their more self‐interested organizational needs.     

Operation scheduling with GT and PBC

Generations of managers in industry and of academics in universities, have been intrigued by the problem of how to plan, and more recently how to automate the scheduling of the operations needed to make parts, on the machines and other work centres in a factory. Today, with one possible exception (OPT) (Goldratt 1980), we are no nearer a reliable solution than we were 100 years ago. Early attempts at centralized operation scheduling, were based on Gantt charts or planning boards. Later solutions have used the computer. They all face the problems that with traditional forms of organization, there is a very large number of constraints which affect the solution, and that if a machine-breakdown, absent worker, material shortage or other disaster makes it necessary to change the schedule, it is generally impossible to revise it to suit the new situation quickly enough to keep the factory running. The usual solution is: ‘Tell the foreman to do the best he can’. This paper submits that the introduction of group technology (GT), coupled with period batch control (PBC), so simplifies the problem, that with minor analytical assistance the GT group foremen can do their own operation scheduling, more reliably and cheaply than it can be done by the computer.     

A FUZZY ALGORITHMIC APPROACH TO THE CONSTRUCTION OF COMPOSITE INDICES: AN APPLICATION TO A FUNCTIONAL LIMITATION INDEX

This paper presents a fuzzy algorithmic approach to the construction of composite indices. The method uses a fuzzy analytic translation of a linguistic definition of the composite index, where the definition involves more primary concepts for which scales already exist. An application to the construction of a functional limitation index is presented. Comparisons between the fuzzy algorithmic approach and a more standard, tabular approach are also shown. The results suggest that the fuzzy algorithmic approach yields essentially the same index with less effort and some conceptual advantages.     

Low Level Light Intensity Measurement from Repetitive Signals†

Background noise is a limiting factor in many cases where photo-electric measurement of light intensities is made. In the present case this problem is dealt with and the effect of noise reduced by special electronic circuit techniques for the study of temporal variations of light emission from microsecond transient discharges. The electronic circuits are dealt with in some detail, and examples are given of the uses to which the apparatus can be put.