Radiation curing has become one of the most significant developments ever to reach the printing a... more Radiation curing has become one of the most significant developments ever to reach the printing and coating field. The great amount of interest has resulted from the many potential benefits obtained by this form of curing. The characteristics and advantages are discussed and actual commercial examples of radiation cure use have been cited in many instances.
The advent of “wide bore,” high‐field, high‐homogeneity magnets in the 1970s provided the opportu... more The advent of “wide bore,” high‐field, high‐homogeneity magnets in the 1970s provided the opportunity to use nuclear magnetic resonance spectroscopy for nondestructive chemical analysis of intact biological systems. Surface or local coils, when used as NMR receivers, provide the NMR experiment with both high signal‐to‐noise sensitivity and a good degree of spatial discrimination. Such attributes are critical to the examination of biological processes in laboratory animals and human patients when concentrations of the metabolites of interest are low and when the sample is characterized by large‐scale heterogeneity, i.e., there are different tissues and organs of interest. The high signal sensitivity also provides for very high spatial resolution when such receivers are used in magnetic resonance imaging of regions such as the spine. This article describes the basic principles of surface coil NMR with the aim of illuminating the concepts underlying its widespread application for in vi...
SUMMARY Two foster care executives encourage agency and parent leaders to rethink their relations... more SUMMARY Two foster care executives encourage agency and parent leaders to rethink their relationships to improve the lives of children in their shared custody. When mothers-of-color charged that white privilege harmed rather than helped children, the white executives connected the accusation to their experience as closeted gay leaders in a religiously-run organization. That unexpected insight became the sharper lens through which they saw some emotional damage caused by their decisions. The executives examined their behavior and transformed their adversarial relationship with parents into a partnership. Their suggestions are based on efforts with parents, mistakes with trustees, and hard lessons learned.
In the mid-1970s I was a physical chemistry graduate student in Gary Maciel’s group in the Depart... more In the mid-1970s I was a physical chemistry graduate student in Gary Maciel’s group in the Department of Chemistry at Colorado State University. My research life had been consumed with liquid and solid state multinuclear MR experiments particularly those involving metal nuclides. David Hoult came by to give a seminar. He talked about the marvelous high sensitivity 31P NMR spectrometer he and his University of Oxford colleagues had put together under the aegis of the Rex Richards/George Radda research group. David showed beautiful new results demonstrating detection of the major phosphorus metabolites in intact isolated muscle tissue. A few years later I found myself an NIH postdoctoral fellow in the same University of Oxford laboratory. Space was limited. I shared a desk along with Tom Grove, a NATO postdoctoral fellow, and Gordon Wong, a Rhodes Scholar. David Gadian, a bright young physicist, was now taking over the science reins from Rex Richards. Despite his time-consuming high level administrative duties as Warden of Merton and Vice Chancellor, Rex still dropped into the laboratory now and then to talk science and be brought up to date on recent developments. David Hoult had left for the NIH in Bethesda and spectrometer building and design were now in the very capable hands of Peter Styles, Rod Porteous and Nick Soffe. A principal focus of the laboratory was on perfused organ 31P NMR experiments with the Radda group exploring rat heart physiology and Gadian and co-workers pursuing frog skeletal muscle metabolism. Efforts focused on carefully excising the tissue or organ of interest and interfacing the sample to a perfusion support system. True to everyone’s training in the dogma of high-resolution NMR, and as had been done for decades before, the sample was placed inside the NMR antenna coil. Prior to placing the tissue in the magnet the static field homogeneity was optimized by shimming on a test sample containing a concentrated phosphorus solution so as to give a strong 31P free induction decay. My first contribution was to introduce a technique taught to me by my close friend and mentor Jerry Dallas who had also been a graduate student in the Maciel group pursuing multinuclear MR. This was that one can often shim on the solvent 1H free induction decay even if the antenna coil is frequency tuned and impedance matched for a nuclide at a different resonance frequency, say that of 31P. Although this idea met with some disbelief at first among my Oxford coworkers, the 1H tissue water signal was found to be very strong from the 31P antenna coils used for perfused rat heart and other organs. One could now routinely shim directly on the tissue sample of interest.1 The 31P linewidth resolution improved significantly. For example, the intracellular and extracellular inorganic phosphate signals in perfused rat heart were now readily resolved. The respective pH values were determined from their chemical shifts. Tom Grove and I became good friends. We also were pursuing perfused rat heart experiments.2 Tom decided to explore the possibility of studying the tissue in situ by implanting the antenna coil about the heart with the entire rat, fully anesthetized and breathing on a respirator, then going into the magnet. This approach required rather radical surgery and taught me a great deal about antenna loading by lossy conductive samples. Nevertheless, the experiments worked well and were, I believe, perhaps the first localized in situ and in vivo 31P measurements.3 Flush with this success, we joined with Gordon Wong—a budding molecular biologist trapped for a short while in an NMR laboratory—to repeat this approach with rat kidney. Gordon, under the guidance of David Gadian and Brian Ross, had been struggling mightily with a difficult perfused kidney preparation.4 Tom and I thought the implanted coil offered perhaps a better idea. It was not to be. Try as we might, the in vivo 31P kidney spectra showed substantial levels of phosphocreatine, a compound essentially absent in renal tissue but not in the surrounding muscle tissue. Clearly the antenna coil so carefully designed to surround the kidney was exciting and detecting signals from outside the coil. I remember well the repeated unsuccessful attempts to pack gauze pads about the coil in an attempt to push the surrounding tissue out of the antenna coil’s transmission/reception range. It was 2 a.m., the jokes were getting stale and tempers a bit edgy, when I realized the all-too-simple lesson in front of us: samples don’t have to be inside the antenna coil to be detected. I walked out of the spectrometer room and down the hall to our office. This cramped space also served as the coil-design electronics laboratory. The first surface coil was wound. A simple tank circuit frequency-tuned and impedance-matched the surface coil to 31P—80 MHz at 4.2 T. I returned to the spectrometer room to find even more gauze packed about the implanted kidney coil. Tom and Gordon were…
Data are presented from 133Cs NMR studies on both excised and in situ tissues from rats fed a reg... more Data are presented from 133Cs NMR studies on both excised and in situ tissues from rats fed a regular diet and administered i.p. CsCl in aqueous solution for 6 to 14 days. Cesium is an NMR‐active potassium analog which accumulates in the intracellular spaces of tissues [Davies et al., Biochemistry 27, 3547 (1988); Shehan, B.P. et al., Magn. Reson. Med. 30, 573 (1993)]. Chemical shifts, relaxation properties, sensitivity and detectability of cesium in tissues were investigated. Consistent with previous reports, two resonances (representing intra‐ and extracellular cesium) were detected in blood. Only one resonance was detected in brain, kidney, and muscle tissue. Efforts to resolve intra‐ and extracellular components by T1 and T2 relaxation discrimination were not successful. Following i.p. administration, cesium accumulates intracellularly with a brain‐to‐cerebrospinal fluid concentration (μmol/g) ratio of 9:1 and a thigh muscle‐to‐plasma concentration ratio of 40:1. Considering the...
Radiation curing has become one of the most significant developments ever to reach the printing a... more Radiation curing has become one of the most significant developments ever to reach the printing and coating field. The great amount of interest has resulted from the many potential benefits obtained by this form of curing. The characteristics and advantages are discussed and actual commercial examples of radiation cure use have been cited in many instances.
The advent of “wide bore,” high‐field, high‐homogeneity magnets in the 1970s provided the opportu... more The advent of “wide bore,” high‐field, high‐homogeneity magnets in the 1970s provided the opportunity to use nuclear magnetic resonance spectroscopy for nondestructive chemical analysis of intact biological systems. Surface or local coils, when used as NMR receivers, provide the NMR experiment with both high signal‐to‐noise sensitivity and a good degree of spatial discrimination. Such attributes are critical to the examination of biological processes in laboratory animals and human patients when concentrations of the metabolites of interest are low and when the sample is characterized by large‐scale heterogeneity, i.e., there are different tissues and organs of interest. The high signal sensitivity also provides for very high spatial resolution when such receivers are used in magnetic resonance imaging of regions such as the spine. This article describes the basic principles of surface coil NMR with the aim of illuminating the concepts underlying its widespread application for in vi...
SUMMARY Two foster care executives encourage agency and parent leaders to rethink their relations... more SUMMARY Two foster care executives encourage agency and parent leaders to rethink their relationships to improve the lives of children in their shared custody. When mothers-of-color charged that white privilege harmed rather than helped children, the white executives connected the accusation to their experience as closeted gay leaders in a religiously-run organization. That unexpected insight became the sharper lens through which they saw some emotional damage caused by their decisions. The executives examined their behavior and transformed their adversarial relationship with parents into a partnership. Their suggestions are based on efforts with parents, mistakes with trustees, and hard lessons learned.
In the mid-1970s I was a physical chemistry graduate student in Gary Maciel’s group in the Depart... more In the mid-1970s I was a physical chemistry graduate student in Gary Maciel’s group in the Department of Chemistry at Colorado State University. My research life had been consumed with liquid and solid state multinuclear MR experiments particularly those involving metal nuclides. David Hoult came by to give a seminar. He talked about the marvelous high sensitivity 31P NMR spectrometer he and his University of Oxford colleagues had put together under the aegis of the Rex Richards/George Radda research group. David showed beautiful new results demonstrating detection of the major phosphorus metabolites in intact isolated muscle tissue. A few years later I found myself an NIH postdoctoral fellow in the same University of Oxford laboratory. Space was limited. I shared a desk along with Tom Grove, a NATO postdoctoral fellow, and Gordon Wong, a Rhodes Scholar. David Gadian, a bright young physicist, was now taking over the science reins from Rex Richards. Despite his time-consuming high level administrative duties as Warden of Merton and Vice Chancellor, Rex still dropped into the laboratory now and then to talk science and be brought up to date on recent developments. David Hoult had left for the NIH in Bethesda and spectrometer building and design were now in the very capable hands of Peter Styles, Rod Porteous and Nick Soffe. A principal focus of the laboratory was on perfused organ 31P NMR experiments with the Radda group exploring rat heart physiology and Gadian and co-workers pursuing frog skeletal muscle metabolism. Efforts focused on carefully excising the tissue or organ of interest and interfacing the sample to a perfusion support system. True to everyone’s training in the dogma of high-resolution NMR, and as had been done for decades before, the sample was placed inside the NMR antenna coil. Prior to placing the tissue in the magnet the static field homogeneity was optimized by shimming on a test sample containing a concentrated phosphorus solution so as to give a strong 31P free induction decay. My first contribution was to introduce a technique taught to me by my close friend and mentor Jerry Dallas who had also been a graduate student in the Maciel group pursuing multinuclear MR. This was that one can often shim on the solvent 1H free induction decay even if the antenna coil is frequency tuned and impedance matched for a nuclide at a different resonance frequency, say that of 31P. Although this idea met with some disbelief at first among my Oxford coworkers, the 1H tissue water signal was found to be very strong from the 31P antenna coils used for perfused rat heart and other organs. One could now routinely shim directly on the tissue sample of interest.1 The 31P linewidth resolution improved significantly. For example, the intracellular and extracellular inorganic phosphate signals in perfused rat heart were now readily resolved. The respective pH values were determined from their chemical shifts. Tom Grove and I became good friends. We also were pursuing perfused rat heart experiments.2 Tom decided to explore the possibility of studying the tissue in situ by implanting the antenna coil about the heart with the entire rat, fully anesthetized and breathing on a respirator, then going into the magnet. This approach required rather radical surgery and taught me a great deal about antenna loading by lossy conductive samples. Nevertheless, the experiments worked well and were, I believe, perhaps the first localized in situ and in vivo 31P measurements.3 Flush with this success, we joined with Gordon Wong—a budding molecular biologist trapped for a short while in an NMR laboratory—to repeat this approach with rat kidney. Gordon, under the guidance of David Gadian and Brian Ross, had been struggling mightily with a difficult perfused kidney preparation.4 Tom and I thought the implanted coil offered perhaps a better idea. It was not to be. Try as we might, the in vivo 31P kidney spectra showed substantial levels of phosphocreatine, a compound essentially absent in renal tissue but not in the surrounding muscle tissue. Clearly the antenna coil so carefully designed to surround the kidney was exciting and detecting signals from outside the coil. I remember well the repeated unsuccessful attempts to pack gauze pads about the coil in an attempt to push the surrounding tissue out of the antenna coil’s transmission/reception range. It was 2 a.m., the jokes were getting stale and tempers a bit edgy, when I realized the all-too-simple lesson in front of us: samples don’t have to be inside the antenna coil to be detected. I walked out of the spectrometer room and down the hall to our office. This cramped space also served as the coil-design electronics laboratory. The first surface coil was wound. A simple tank circuit frequency-tuned and impedance-matched the surface coil to 31P—80 MHz at 4.2 T. I returned to the spectrometer room to find even more gauze packed about the implanted kidney coil. Tom and Gordon were…
Data are presented from 133Cs NMR studies on both excised and in situ tissues from rats fed a reg... more Data are presented from 133Cs NMR studies on both excised and in situ tissues from rats fed a regular diet and administered i.p. CsCl in aqueous solution for 6 to 14 days. Cesium is an NMR‐active potassium analog which accumulates in the intracellular spaces of tissues [Davies et al., Biochemistry 27, 3547 (1988); Shehan, B.P. et al., Magn. Reson. Med. 30, 573 (1993)]. Chemical shifts, relaxation properties, sensitivity and detectability of cesium in tissues were investigated. Consistent with previous reports, two resonances (representing intra‐ and extracellular cesium) were detected in blood. Only one resonance was detected in brain, kidney, and muscle tissue. Efforts to resolve intra‐ and extracellular components by T1 and T2 relaxation discrimination were not successful. Following i.p. administration, cesium accumulates intracellularly with a brain‐to‐cerebrospinal fluid concentration (μmol/g) ratio of 9:1 and a thigh muscle‐to‐plasma concentration ratio of 40:1. Considering the...
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