[Axis I "illness experience and treatment preconditions" of operational psychodynamic diagnosis (OPD). Experiences in clinical practice]. / Die Achse I "Krankheitserleben und Behandlungsvoraussetzungen" der Operationalisierten Psychodynamischen Diagnostik (OPD). Erfahrungen in der klinischen Praxis.

In a selective survey, results on psychometric properties and aspects of application of the axis I, "illness experience and treatment preconditions" of the Operational Psychodynamic Diagnoses (OPD) are described. Following remarks on the role of defense and coping theories in the conceptualisation of the axis, its structure and contents are outlined. After a brief summary of findings on its interrater reliability, several aspects of validity are discussed. Results on discriminative validity show that axis I items are useful in the statistical discrimination of subsamples differing in age, clinical diagnoses, and diagnostic setting (psychotherapy outpatient vs. psychosomatic consultation-liasion services). The contribution of axis I items to prediction of treatment outcomes, moreover, reveals high degree of predictive or treatment validity. After an integrative discussion of these findings, implications of patient personality and coping behaviour for axis I ratings are highlighted as important objectives for future OPD research.

Survey of Meloidogyne incognita and Thielaviopsis basicola: Their Impact on Cotton Fruiting and Producers' Management Choices in Infested Fields.

A survey of 100 cotton fields selected randomly in 1995 and 1996 was conducted in the High Plains of Texas to determine the incidence and potential severity of Meloidogyne incognita and Thielaviopsis basicola. Information was obtained from producers for each field on their nematicide application rates and fungicide seed treatments. The percent of squares and bolls set was evaluated for 20 plants in each field during late July 1995 and early August 1996. Thielaviopsis basicola was identified in 55% of the fields in 1995 and 73% of the irrigated fields in 1996. Meloidogyne incognita was found in 39% and 43% of the fields in 1995 and 1996, respectively. Both M. incognita and T. basicola were found together in approximately 30% of the fields. The average rate of aldicarb used in 1995 and 1996 was higher when fields were infested with both T. basicola and M. incognita than for fields infested with none or only one of the pathogens. However, there was no relationship between the use of fungicide treatments active against T. basicola and the potential for root necrosis, or presence of either or both pathogens (T. basicola and M. incognita). Aldicarb rates and usage of fungicide seed treatments were chosen by producers before fields were surveyed (i.e., the survey did not influence grower practices). In 1995, but not in 1996, the association of M. incognita and potential root necrosis (based on a bioassay from soil samples) was negatively correlated with the number of squares, percentage of squares set, and percentage of bolls set. The association between M. incognita and T. basicola, or potential severity of root necrosis, could not be correlated with fruit attributes in 1996 under warm spring conditions but was negatively correlated with fruit attributes in 1995 under cool spring conditions.

Two-gradient-echo, two-dimensional, Fourier transform multisection imaging: comparison with spin-echo imaging.

A multisection, two-dimensional, Fourier transform, double-gradient-echo magnetic resonance imaging sequence with partial flip-angle excitation and section doubling by radiofrequency encoding approximately doubles the signal-to-noise ratio obtainable from a conventional spin-echo sequence at low field strength, while maintaining essentially equivalent contrast.

Low-field 3-DFT MRI: conceptual, analytical, and experimental aspects.

Three-dimensional Fourier transform (3-DFT) magnetic resonance imaging (MRI) offers advantages in terms of signal-to-noise (S/N) per unit of time for the case where a large number of slices is desired. This advantage is enhanced when the relaxation time, T(1 ), is short. Because time limitations in 3-DFT imaging force the use of short time intervals, TR, between excitations of a slice, lesion contrast is often undesirable at mid-and high-field strength even when the S/N is good. At low fields, where T(1) values are short, high S/N and contrast can both be achieved with 3-DFT MR images. The conceptual and analytical aspects of low-field 3-DFT MRI are presented and demonstrated at 640 G.

Accessible magnetic resonance imaging.

The cost of magnetic resonance imaging (MRI) is driven by magnetic field strength. Misperceptions as to the impact of field strength on performance have led to systems that are more expensive than they need to be. Careful analysis of all the factors that affect diagnostic quality lead to the conclusion that field strength per se is not a strong determinant of system performance. Freed from the constraints imposed by high-field operation, it is possible to exploit a varied set of opportunities afforded by low-field operation. In addition to lower costs and easier siting, we can take advantage of shortened T1 times, higher contrast, reduced sensitivity to motion, and reduced radiofrequency power deposition. These conceptual advantages can be made to coalesce onto practical imaging systems. We describe a low-cost MRI system that utilizes a permanent magnet of open design. Careful optimization of receiving antennas and acquisition sequences permit performance levels consistent with those needed for an effective diagnostic unit. Ancillary advantages include easy access to the patient, reduced claustrophobia, quiet and comfortable operation, and absence of a missile effect. The system can be sited in 350 sq ft and consumes a modest amount of electricity. MRI equipment of this kind can widen the population base than can access this powerful and beneficial diagnostic modality.