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K Weingarten

Publications and source records attributed to K Weingarten.

At least 19 recordsLinked to original sources
PubMed2000

Comparative study of motions in dimethylsulfone by noise excitation and solid echo spectroscopy.

2H NMR spectra of dimethylsulfone were measured with noise excitation and solid echo NMR spectroscopy in the temperature range from 125 to 355 K. Besides the known fact that broad NMR spectra can be measured with both methods, in comparable times it is shown that for noise excitation, the signal loss is negligible compared to echo spectroscopy in the regime when the correlation times of the motions are of the order of magnitude of the echo pulse spacing. For simulating the dynamic NMR spectra acquired with noise excitation, only the motional process must be taken into account and relaxation can be neglected. Furthermore, the problem of restricted acquisition bandwidth in noise NMR spectroscopy is discussed.

Cold Temperature↗
PubMed2000

Witnessing, wonder, and hope.

This article is based on a keynote address I gave in South Africa at the Eighth International Conference of The South African Association of Marital and Family Therapy. The phenomenon of witnessing is explored in a number of contexts, and a distinction is made between witnessing with and without awareness, and from an empowered or a disempowered position. I propose that the African philosophy of ubuntu--the emphasis of which is on the self in community, in contrast to the Western emphasis on the individual--may be a better fit for my view of hope, which, I propose, is not just a feeling but, rather, something people do.

Anecdotes as Topic↗
PubMed1999

Conservative management of extra-axial hematomas diagnosed by CT.

Our purpose was to assess the role of serial CT in recently traumatized patients with clinically stable extra-axial intracranial hematomas (EACH) and a midline shift of less than 0.5 cm. A retrospective review of 91 imaging studies in 41 patients (with 45 EACH) was done to assess the time between trauma and CT; the presence and type of skull fracture; the volume, type, and location of the EACH; the presence of associated edema and/or contusion. Over a 19-day follow-up, 11% of the dense EACH increased in volume and 27% decreased. An adjacent skull fracture was seen most frequently in patients with a decrease in EACH volume. Clinical data remain the key to determining the need for neurosurgical intervention in patients with EACH. Follow-up CT afforded no data which altered the medical management of these patients. However, it may be said to have alerted the clinician to an increase in the size of the EACH in 11% of cases, which could mandate close observation of this group.

Adolescent↗
PubMed1998

Radiologist evaluation of a multispectral image compression algorithm for magnetic resonance images.

With the advent of teleradiology and picture archiving and communication systems (PACS), the expense and time required for image transmission and long term image archiving become important. The use of validated image compression algorithms can greatly reduce these costs. A lossy, multispectral image compression scheme at compression ratios (CR) of 25:1 and 32:1 was used for a set of 26 different patient MR exams. The original and compressed/decompressed (CD) images sets were evaluated in a blinded fashion by four radiologists in two phases. The main objective was to determine whether radiologic interpretation would vary between the two types of CD image sets and the corresponding originals. In general, the compression algorithm caused a slight decrease in image quality; however, the interpretation of pathology did not change between the original and CD image sets. In only one case at the maximum CR = 32 did one of four radiologists change the interpretation of pathology after CD. In this study, lossy multispectral image compression of MR images at CR = 25 maintained diagnostic integrity. This could play a significant role in image storage and communications.

Algorithms↗
PubMed1998

The small and the ordinary: the daily practice of a postmodern narrative therapy.

In this article, I contrast assumptions of a modernist worldview and a postmodern worldview as they relate to clinical practice. Two exercises are described that help therapists develop insight into and practice with the kind of thinking that is consistent with a postmodern narrative clinical practice. Particular attention is paid to the ways that even the small and the ordinary--single words, single gestures, minor asides, trivial actions--can provide opportunities for generating new meanings. Five concepts that I routinely use in my professional and personal life and that are consistent with a postmodern narrative practice--discourse, externalizing the internalized discourse, exceptions, power as the means to produce a consensus, and characteristics of narrative--are illustrated.

Adult↗
PubMed1995

Effects of carbon dioxide arterial infusion on hepatic biochemistry and histology in a rabbit model.

RATIONALE AND OBJECTIVES: The objective of this study was to determine the effect of carbon dioxide (CO2) infusion on hepatic biochemistry and histology in a rabbit model. METHODS: The study population consisted of 24 anesthetized rabbits that received hepatic infusion of either CO2 or saline (control) at doses of 10 mL/kg, comparable with those doses used in human clinical trials. Blood for clinical chemistry analysis was collected at baseline, 1 hour, 24 hours, and 168 hours (7 days) postprocedure. The rabbits were killed at 7 days postprocedure and the liver examined histologically for hepatic damage. RESULTS: There were no significant differences between the CO2 and the control groups in dorsal, ventral, and dorsal/ventral scores. Increases in alanine, an important indicator of hepatocellular membrane injury, in the CO2 group were significantly greater at 1 hour and 24 hours posttreatment (P = 0.037 and 0.013). However, the mean levels at 168 hours (7 days) were not significantly different (P = 0.22). The increases at 1 and 24 hours were small, transient, and considered clinically insignificant. CONCLUSION: No long-term hepatic effects in these animals were suggested by biochemical and histological examinations.

Analysis of Variance↗
PubMed1995

Timing disclosure sessions: adding a narrative perspective to clinical work with adult survivors of childhood sexual abuse.

Though the literature on the diagnosis and treatment of survivors of childhood sexual abuse has burgeoned in the last 20 years, relatively little guidance is available in the popular or professional literature to assist clients or therapists about issues of disclosure of this abuse to family members. When authors explicitly focus on disclosure, the timing of such disclosure is usually framed within a psychological and/or interpersonal perspective. In this article, we suggest that attention to characteristics of the sexual abuse narrative itself offers an important additional resource to guide decision making with respect to disclosure. We also describe ways that a narrative approach to disclosure can produce empowering conversational practices. A detailed case example provides the clinical material to illustrate this narrative approach to disclosure.

Adaptation, Psychological↗
PubMed1994

Acute hypertensive encephalopathy: findings on spin-echo and gradient-echo MR imaging.

OBJECTIVE: The purpose of this study was to investigate the findings on spin-echo and gradient-echo MR images obtained in patients with hypertensive encephalopathy. SUBJECTS AND METHODS: The MR images of 36 patients with clinically documented acute (< 72 hr) hypertensive encephalopathy were prospectively examined. Brain swelling on short TR images, hyperintensity on long TR images, and hypointensity on long TR and gradient-echo images were assessed. RESULTS: The most common finding was hyperintensity in the supratentorial white matter (n = 32), representing hypertensive encephalopathy-induced reversible edema, irreversible infarction, or preexisting ischemic disease. These entities were difficult to distinguish on the basis of the initial examination. A more characteristic finding was edema (swelling on short TR images and hyperintensity on long TR images) in the basal ganglia (n = 22), brainstem (n = 15), and cerebellum (n = 11). Punctate foci of hypointensity, seen on long TR spin-echo images but optimally visualized on gradient-echo images, were the most distinguishing feature of this disorder. CONCLUSION: MR imaging is efficacious in revealing deep ganglionic and posterior fossa edema, which is characteristic of hypertensive encephalopathy. Serial MR studies are necessary to distinguish transient edema from permanent zones of infarction. Gradient-echo MR imaging is particularly valuable in visualizing petechial hemorrhages, the presence of which distinguishes nonspecific white matter disease from an acute or prior episode of hypertensive encephalopathy and serves as a permanent marker of this disease.

Adolescent↗
PubMed1994

Symptomatic lumbar epidural varices. Report of two cases.

Lumbar epidural varices have been infrequently described in the literature and rarely accepted as a primary pathophysiological entity. The authors' total experience with symptomatic lumbar epidural varices over the last 15 years includes four cases (incidence 0.067% of all lumbar spine operations), two of which are described in detail in this paper. The mechanism for their formation is proposed: central disc herniations obstruct the anterior epidural venous flow leading to anterolateral caudal venous distention. Subsequent venous endothelial injury predisposes to varying degrees of phlebothrombosis. Decompression of partially thrombosed varices may occur during operative discectomy or spontaneously during regression of the nonoperated disc prolapse. Regression of the central disc herniation may also explain the "disappearing disc" phenomenon, in which patients with clinical and radiographic evidence of apparently large caudal disc herniations exhibit clinical and radiographic resolution. Magnetic resonance (MR) imaging characteristics of the epidural varix depend upon the degree of thrombosis within this anomaly. A thrombosed varix is hyperintense on T1-weighted, proton-density, and T2-weighted images, whereas flowing blood is hypointense. The variable hypo- and hyperintensity on the T2-weighted MR imaging sequences correlate with a partially patent lumen within the varix.

Adult↗
PubMed1992

A consideration of intimate and non-intimate interactions in therapy.

Viewing therapy as a conversation among participants, rather than as an interview concluding with an intervention selected by an expert, allows one to consider the contributions of each member of the conversation in comparable terms. I propose a distinction between intimate interaction, in which meaning is co-created or shared, and non-intimate interaction, in which meaning is rejected, provided, or misunderstood. I suggest that intimate interaction between therapists and clients is therapeutic and that non-intimate interaction rarely is. However, it is in the acknowledgment and repair of the inevitable lapses of intimate interaction that occur between therapists and clients that there is an opportunity for a profoundly meaningful collaboration.

Family Therapy↗
PubMed1992

Detection of residual or recurrent meningioma after surgery: value of enhanced vs unenhanced MR imaging.

The enhanced and unenhanced MR examinations obtained after surgery for meningioma in 38 patients were reviewed to determine the value of enhanced vs unenhanced MR imaging for the detection of residual or recurrent tumor. Enhanced images improved delineation of the extent of tumor in seven of 13 cases in which meningioma was identified on unenhanced images and allowed more definitive detection or exclusion of residual or recurrent meningioma in 18 of 21 cases with equivocal findings on unenhanced images. In addition, enhanced images were helpful for detecting small recurrences, identifying en plaque growth, and showing subtle progression on serial studies. Enhanced MR imaging also allowed detection of two morphologic patterns of dural enhancement adjacent to the surgical bed: (1) thin and smooth, which was seen in patients both with and without residual or recurrent tumor, and (2) thick and nodular, which was seen only in patients with findings indicative of, or at least suggestive of, residual or recurrent meningioma. Unenhanced images failed to detect, or poorly detected, these dural abnormalities. Unenhanced sequences were necessary for accurate interpretation of the enhanced images (e.g., identification or exclusion of hemorrhage). The combination of unenhanced and enhanced MR imaging is recommended for the detection of residual or recurrent meningioma after surgery.

Adult↗
PubMed1991

The discourses of intimacy: adding a social constructionist and feminist view.

Though most people desire intimacy in their primary relationships, it is more elusive than not. I argue that people's assumptions about intimacy interfere with their creation of it. Using a social constructionist and feminist perspective, two prevailing discourses of intimacy that shape our ideas about intimacy are identified and critiqued. Both tend to direct attention away from an assessment of particular interactions to a global assessment of the capacity of an individual or a relationship to provide intimacy. An alternative is proposed in which intimacy is conceptualized as built up from single intimate or non-intimate interactions that can produce a variety of experiences, including connection and domination. My critique of the two discourses of intimacy rests fundamentally on the belief that they obscure crucial distinctions that a discourse of intimacy as meaning-making would reveal, in particular, that there are politics nestled in the heart of intimacy.

Adaptation, Psychological↗
PubMed1990

The effect of cadmium and other metals on vascular smooth muscle of the dogfish shark, Squalus acanthias.

The effect of Cd2+ and related metals (Ni2+, Hg2+, Pb2+, Co2+, Sn2+ Cu2+ and Zn2+) on vascular tension was studied using isolated rings of endothelium-free, smooth muscle from the ventral aorta of the shark, Squalus acanthias. Both Cd2+ and Ni2+ produced significant vasoconstriction at concentrations at or above 10(-6) M (112 and 59 ppb, respectively); the other metals were either marginally constrictive (Hg2+ and Sn2+) or were without effect (Pb2+, Co2+, Cu2+, and Zn2+). We suggest that previously published vascular effects of Hg2+ and Pb2+ may have been secondary to responses of the vascular endothelium, and that the role of Ni2+ in hypertension should be investigated further. Our data indicate that the effects of metals on this vascular smooth muscle are specific and not generic. Moreover, this system could be utilized to investigate the mechanisms of metal-induced vasoconstriction.

Animals↗
PubMed1989

Intraspinal extension of an air cyst of the lung: case report.

We report the diagnostic evaluation and treatment of a cystic paraspinal and epidural lesion originally thought to be a neurofibroma or an arachnoid cyst. Intraoperatively, the lesion was found to be an air cyst of the lung that was successfully ligated.

Adult↗
PubMed1989

Subdural and epidural empyemas: MR imaging.

The MR images of six patients with extraaxial empyemas (five subdural and four epidural) were reviewed and compared with CT scans. MR demonstrated convexity and interhemispheric collections, which were mildly hyperintense relative to CSF and hypointense relative to white matter on short TR pulse sequences and hyperintense relative to CSF and white matter on long TR pulse sequences, allowing distinction from sterile effusions and most chronic hematomas. A hypointense rim, representing displaced dura, was depicted at the interface between the lesion and brain in epidural empyemas, a feature absent in subdural empyemas. Inflammation-induced parenchymal abnormalities, including edema, mass effect, and reversible cortical hyperintensity, were well depicted on MR imaging. MR was superior to CT in demonstrating the presence, nature, and extent of these lesions in all cases. Because early and accurate diagnosis will significantly improve the prognosis of these serious infections, MR is preferred to CT for patients in whom an acute intracranial infection is suspected.

Adolescent↗
PubMed1989

MR imaging of brain abscesses.

The MR images and CT scans of 14 patients with surgically verified pyogenic cerebral abscesses were reviewed. The MR findings correlated well with those seen on CT and were believed to be sufficiently characteristic to allow early and accurate diagnosis with MR alone. These features include (1) peripheral edema producing mild hypointensity on short TR/short TE and marked hyperintensity on long TR/intermediate to long TE scans; (2) central necrosis with abscess fluid hypointense relative to white matter and hyperintense relative to CSF on short TR/short TE scans and hyperintense relative to gray matter on long TR/intermediate to long TE scans (the fluid had concentric zones of varying intensity in seven cases, a finding not previously identified in other lesions); (3) extraparenchymal spread (intraventricular or subarachnoid), which was detected more easily on MR than on CT and was manifested by increased intensity relative to normal CSF on both short TR/short TE and long TR/intermediate TE scans; and (4) visualization of the abscess capsule, which was iso- to mildly hyperintense relative to brain on short TR/short TE scans and iso- to hypointense relative to white matter on long TR/intermediate to long TE scans. On the long TR scans, the relative hypointensity of the rim allowed for visualization of the typical morphologic features of the capsule, which in turn aided in differentiation of abscesses from other lesions (as it does on CT). To investigate the cause of the capsular intensity, pathologic studies of the capsules were reviewed when available (10 cases). Fibrosis was identified in all mature abscess capsules, but the combination of the intensities seen on short TR/short TE and long TR/intermediate to long TE scans as well as the temporal changes in intensity were believed to be incompatible with fibrosis as a cause of the capsular changes. Intensity patterns were suggestive of hemorrhage, but neither acute nor chronic hemorrhage was identified on routine H and E stains, while iron stain revealed scant hemorrhage in only two of the eight patients in whom these stains were used. We believe the capsular intensity (in particular the hypointense rims on long TR scans) may reflect paramagnetic T1, and to a greater extent T2, shortening, possibly due to the presence of heterogeneously distributed free radicals that are products of the respiratory burst produced by actively phagocytosing macrophages in the capsule wall. Distinctive MR features of pyogenic abscesses should afford early and accurate diagnosis.

Brain↗
PubMed1979

Family awareness for nonclinicians: participation in a simulated family as a teaching technique.

This paper describes a course in family theory geared to "well" family members that combines didactic and experiential teaching techniques. A key feature of the course is that students participate in a simulated family for twelve weeks. Family therapists are skilled at using techniques that powerfully dramatize family process; they can provide a needed and useful service to the community by teaching the dynamics of families functioning to people who have a personal or professional interest in learning more about families.

Awareness↗