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Notes: Initial experiments to study the Z-pinch-driven hohlraum high-yield inertial confinement fusion (ICF) concept of Hammer, Tabak, and Porter [Hammer et al., Phys. Plasmas 6, 2129 (1999)] are described. The relationship between measured pinch power, hohlraum temperature, and secondary hohlraum coupling ("hohlraum energetics") is well understood from zero-dimensional semianalytic, and two-dimensional view factor and radiation magnetohydrodynamics models. These experiments have shown the highest x-ray powers coupled to any Z-pinch-driven secondary hohlraum (26±5 TW), indicating the concept could scale to fusion yields of 〉200 MJ. A novel, single-sided power feed, double-pinch driven secondary that meets the pinch simultaneity requirements for polar radiation symmetry has also been developed. This source will permit investigation of the pinch power balance and hohlraum geometry requirements for ICF relevant secondary radiation symmetry, leading to a capsule implosion capability on the Z accelerator [Spielman et al., Phys. Plasmas 5, 2105 (1998)]. © 2001 American Institute of Physics.

Notes: JCR:LA-cp/cp obese rats and their lean controls were evaluated as a type 2 diabetic wound healing model and the healing quality was characterized. This model of insulin resistance has been used extensively to study atherosclerosis but has not previously been used to study wound healing. Six circular excisional wounds were made on the dorsum of each rat and followed to day 21.Tracings of the wounds were made and used to assess the rate of wound closure. Planimetry showed a significantly diminished contraction of wounds in obese rats, but no significant difference in reepithelialization was observed. Collagen content was determined from the hydroxyproline content in wounded and unwounded skin. There were significantly lower levels of hydroxyproline in the wounds of obese compared to lean animals at day 21. Histology showed adipose tissue in place of dermal tissue in the JCR:LA-cp/cp rat in both unwounded tissue and in the wound at day 21. Active transforming growth factor-β1 (TGF-β1) was measured in the serum using the plasminogen activator inhibitor-1/luciferase assay and serum total TGF-β was measured using an enzyme-linked immunosorbent assay. Active TGF-β was significantly higher in the serum of obese animals compared with lean animals, while total TGF-β1 was not significantly different between the groups. Both active and total TGF-β was measured in tissue sections using the plasminogen activator inhibitor-1/luciferase assay. There was no significant difference in active TGF-β between genotypes, while obese rats had significantly higher levels of total TGF-β at day 21. These results indicate a deficiency in wound healing in obese animals characterized by decreased wound contraction, decreased collagen production, and changes in histology. The JCR:LA-cp rat develops insulin resistance, atherosclerosis and early type 2 diabetes and may be a good model for impairment of wound healing in humans with metabolic syndrome.

Notes: Winter frosts caused by radiative cooling were hypothesized to limit successful reintroduction of Hawaiian plants other than Acacia koa to alien-dominated grasslands above 1700 m elevation. We determined, in the laboratory, the temperature at which irreversible tissue damage occurred to Metrosideros polymorpha leaves. We also conducted a field study of this species to determine if (1) leaf damage was correlated with sub-zero leaf temperatures, (2) radiative cooling could be moderated by canopies of A. koa, and (3) low soil temperatures contributed to seedling damage. The last was evaluated by thermally buffering seedlings with water-filled bladders placed at their base to keep roots warm, or by installing a radiation shield to reduce early morning transpiration when water uptake from cold soils would be least. Leaf temperatures were monitored between midnight and 7:00 a.m. using fine-wire thermocouples, and leaf damage was recorded monthly. In the laboratory, supercooling protected leaves from mild sub-zero temperatures; irreversible tissue damage occurred at about −8°C. In the field, leaf damage was strongly correlated with degree-hours below freezing. Unprotected seedlings suffered the greatest leaf damage. Those sheltered under A. koa trees rarely experienced temperatures below −3°C, and damage was minimal. Shaded and thermally buffered seedlings suffered less damage than unprotected plants, probably due to elevated leaf temperatures rather than improved water relations. Using A. koa or artificial devices to reduce radiative cooling during winter nights should enhance establishment of M. polymorpha in high-elevation rangeland.

Notes: Transforming growth factor-β1 is a well-known fibrogenic cytokine produced by many types of cells including dermal fibroblasts. To investigate whether this fibrogenic cytokine is involved in development of hypertrophic scar, transforming growth factor-β1 gene expression was evaluated in small skin samples. Because a sufficient quantity of normal skin from patients with hypertrophic scar is not readily available, a reverse transcription-polymerase chain reaction technique was used. Quantitation of gene expression by reverse transcription-polymerase chain reaction is difficult partly due to the lack of suitable complementary RNA standards. We have established a convenient, reliable procedure to construct an internal standard for transforming growth factor-β1 starting with a gene specific polymerase chain reaction product. After digestion of the polymerase chain reaction product with endonuclease, a small piece of cDNA from human procollagen α1(I) cDNA with compatible ends was inserted into the polymerase chain reaction-DNA fragment. The recombinant cDNA was re-amplified by polymerase chain reaction and subcloned into a plasmid containing bacteriophage T7 and T3 promoters. Complementary RNA was prepared from the recombinant plasmid and amplified by reverse transcription-polymerase chain reaction together with the tissue or cellular RNA. After amplification, the products were electrophoresed in an agarose gel containing ethidium bromide. The bands for internal standard and transforming growth factor-β1 mRNA were scanned, digitized, and plotted against the amount of internal standard complementary RNA added in the reverse transcription-polymerase chain reaction. The number of mRNA molecules/cell was calculated. We examined the transforming growth factor-β1 mRNA in hypertrophic scar tissue and in normal skin and found that hypertrophic scar tissues expressed five-fold more transforming growth factor-β1 mRNA than normal skin per unit of wet weight. We used this procedure to quantitate transforming growth factor-β1 mRNA expression in 5 pairs of fibroblast cultures derived from hypertrophic scar and normal skin. The results showed that hypertrophic scar fibroblast cultures contain significantly more molecules of mRNA for transforming growth factor-β1 than normal cells (116 ± 6 vs. 97 ± 7, p = 0.017, n = 5). These results were supported by Northern analysis for transforming growth factor-β1 mRNA in the cells and enzyme-linked immunosorbent assay for TGF-β1 protein in fibroblast-conditioned medium. In conclusion, hypertrophic scar tissue and fibroblasts produce more mRNA and protein for transforming growth factor-β1, which may be important in hypertrophic scar formation. The construction of the gene specific internal standard for reverse transcription-polymerase chain reaction is a simple and reliable procedure useful to quantitate gene expression in a small amount of tissue or number of cells.

Notes: The article explores the evolution of labour politics during the transition from authoritarian to electoral rule in South Korea and Taiwan during the last decade and a half. It argues that labour politics is a crucial aspect of democratic consolidation because it facilitates the reproduction of contingent mass consent to the new regime. To this end, organized labour must be re-positioned as a political and economic actor, something that requires institutional and structural reform away from the authoritarian experience. Based on analysis of the pattern of political insertion and the legal framework governing the interaction between organized labour, business and the state before and after the electoral transition, as well as data on strikes, union density and membership, the essay concludes that substantive change in the labour politics partial regime is minor in both countries and that in fact, democratic consolidation remains an unachieved goal in each.

Notes: Architecture at the Maya archaeological site of Uxmal in Yucatan, Mexico has been documented since the 17th century by historians, archaeologists, illustrators, photographers, and most recently photogrammetrists. This paper reviews the work of the major contributors to recording of architecture at Uxmal with a particular focus on the 19th century stereophotography of Alice and Augustus Le Plongeon who worked to record all the standing architecture at Uxmal, and the close range stereophotogrammetric projects that recorded the Adivino Pyramid during the late 20th century.

Notes: Catheter-based vascular interventions have been in development worldwide for several decades, leading to remarkable progress in device technology. Mechanical interventional devices, such as angioplasty balloons, atherectomy devices, and stents, were invented and have contributed greatly to the treatment of atherosclerotic vascular stenosis. However, mechanical approaches do not effectively prevent subsequent intimal growth. Recently, several biological approaches, including radiation therapy and drug-eluting stents, have shown striking inhibition of intimal growth. These significant results are likely to change the treatment strategy in the field of interventional cardiology. Furthermore, additional catheter-based technologies for vascular interventions are presently being evaluated. These latest technologies designed to prevent intimal proliferation include intravascular sonotherapy, cryotherapy, photoangioplasty, and soft X ray. To date, intravascular sonotherapy has proven its efficacy in animal studies and safety in human studies. Cryotherapy, the application of cold thermal energy during angioplasty, enhances the acute effects of conventional dilation while decreasing the likelihood of restenosis. Photoangioplasty has a unique property based on its selective mechanism of action to treat atheromatous plaque. Soft X ray systems provide convenient device handling and well-controlled radiation dose. Some of these technologies may play an important role in vascular interventions in the near future.

Notes: Neurofilament pathology is a hallmark of sporadic and familial amyotrophic lateral sclerosis (SALS and FALS). The disease mechanisms underlying this pathology are presently unclear, but recent evidence in SALS patients suggest that reductions in neurofilament light subunit (NFL) mRNA may contribute to the death of motor neurones. Mutations in the gene encoding Cu-Zn superoxide dismutase (SOD1) represent the best-studied cause of FALS, and a number of laboratory models of SOD1-mediated disease exist. Here we have used microdissected lumbar spinal cord motor neurones from human SOD1 FALS patients as well as G93A SOD1 transgenic mice and demonstrated that reduced NFL mRNA levels are seen in both. To probe the molecular mechanisms underpinning these observations, we generated NSC34 motor neurone-like cell lines expressing wild-type and mutant SOD1. NSC34 cells expressing G37R or G93A SOD1 showed selective reductions in NFL and NFM mRNA and protein. These data suggest that NFL mRNA reductions are common to SALS and FALS patients, and that cells and mice expressing mutant SOD1 may enable us to characterize the molecular mechanism(s) responsible for the loss of neurofilament mRNA.

Notes: Abstract: Recent data from our laboratory have shown a regionally specific increase in lipid peroxidation in postmortem progressive supranuclear palsy (PSP) brain. To extend this finding, we measured activities of mitochondrial enzymes as well as tissue malondialdehyde (MDA) levels in postmortem superior frontal cortex (Brodmann’s area 9; SFC) from 14 pathologically confirmed cases of PSP and 13 age-matched control brains. Significant decreases (-39%) in α-ketoglutarate dehydrogenase complex/glutamate dehydrogenase ratio and significant increases (+36%) in tissue MDA levels were observed in the SFC in PSP; no differences in complex I or complex IV activities were detected. Together, these results suggest that mitochondrial dysfunction and lipid peroxidation may underlie the frontal metabolic and functional deficits observed in PSP.