Strong Coupling Limit of Bethe Ansatz Solutions in Massive Thirring Model

We study the strong coupling limit of the Bethe ansatz solutions in the massive Thirring model. We find analytical expressions for the energy eigenvalues for the vacuum state as well as n-particle n- hole states. This formula is compared with the numerical results and is found to achieve a very good agreement. Also, it is found that the 2-particle 2- hole and higher particle-hole states describe n- free bosons states in this limit. The behaviors of the strong coupling limit of the boson mass for various model calculations are examined. We discuss an ambiguity of the coupling constant normalization due to the current regularization.Comment: 15 pages, to appear in Ann. Phys. 281 (2000), Ma

Generation of Novel Bone Forming Cells (Monoosteophils) from the Cathelicidin-Derived Peptide LL-37 Treated Monocytes

Bone generation and maintenance involve osteoblasts, osteoclasts, and osteocytes which originate from unique precursors and rely on key growth factors for differentiation. However, an incomplete understanding of bone forming cells during wound healing has led to an unfilled clinical need such as nonunion of bone fractures. Since circulating monocytes are often recruited to sites of injury and may differentiate into various cell types including osteoclasts, we investigated the possibility that circulating monocytes in the context of tissue injury may also contribute to bone repair. In particular, we hypothesized that LL-37 (produced from hCAP-18, cathelicidin), which recruits circulating monocytes during injury, may play a role in bone repair.Treatment of monocytes from blood with LL-37 for 6 days resulted in their differentiation to large adherent cells. Growth of LL-37-differentiated monocytes on osteologic discs reveals bone-like nodule formation by scanning electron microscopy (SEM). In vivo transplantation studies in NOD/SCID mice show that LL-37-differentiated monocytes form bone-like structures similar to endochondral bone formation. Importantly, LL-37-differentiated monocytes are distinct from conventional monocyte-derived osteoclasts, macrophages, and dendritic cells and do not express markers of the mesenchymal stem cells (MSC) lineage, distinguishing them from the conventional precursors of osteoblasts. Furthermore, LL-37 differentiated monocytes express intracellular proteins of both the osteoblast and osteoclast lineage including osteocalcin (OC), osteonectin (ON), bone sialoprotein II (BSP II), osteopontin (OP), RANK, RANKL, MMP-9, tartrate resistant acid phosphatase (TRAP), and cathepsin K (CK).Blood derived monocytes treated with LL-37 can be differentiated into a novel bone forming cell that functions both in vitro and in vivo. We propose the name monoosteophil to indicate their monocyte derived lineage and their bone forming phenotype. These cells may have wide ranging implications in the clinic including repair of broken bones and treatment of osteoporosis

'Think before you buy under-18s drink': evaluation of a community alcohol intervention

Hazardous consumption of alcohol by teenagers is a significant public health problem in New Zealand. Concern about supply of alcohol to minors motivated 'Think before you buy under-18s drink', a campaign to reduce alcohol-related harm by discouraging inappropriate supply of alcohol by adults. Two intervention districts and a comparison district, in the South Island of New Zealand, were selected for the purpose of evaluating the campaign. Primary outcome measures were changes in the prevalence of parent supply to their teenager ( 13-17 years) for unsupervised drinking (SUD), and changes in the prevalence of binge drinking among teenagers. At baseline, 49% of teenagers reported a recent episode of binge drinking. SUD in the past month was reported by 36% of teenagers. Recent purchases of alcohol by under-18s were common ( bottle shops: 16%; pubs/bars: 11%). In contrast to teenagers, only 2% of parents reported SUD in the past month. Levels of binge drinking decreased in all three districts. Analysis of data from 474 teenagers who completed questionnaires, at baseline and follow-up, showed decreased SUD in Ashburton and Waitaki relative to Clutha, although this was not significant ( OR = 0.73; 95% CI: 0.43, 1.25). Discrepancies between teenager and parent reports of SUD may be due to the latter providing a socially desirable survey response and to differences in the interpretation of what constitutes adult supervision. The lack of a significant association between changes in SUD and binge drinking may be a consequence of teenagers obtaining relatively small amounts of alcohol from their parents and larger quantities from other sources, e. g. peers ( some of whom may be able to purchase alcohol legally) and from licensed premises

<i>In Situ</i> Formation of Cobalt Oxide Nanocubanes as Efficient Oxygen Evolution Catalysts

Oxygen evolution from water poses a significant challenge in solar fuel production because it requires an efficient catalyst to bridge the one-electron photon capture process with the four-electron oxygen evolution reaction (OER). Here, a new strategy was developed to synthesize nonsupported ultrasmall cobalt oxide nanocubanes through an <i>in situ</i> phase transformation mechanism using a layered Co­(OH)­(OCH₃) precursor. Under sonication, the precursor was exfoliated and transformed into cobalt oxide nanocubanes in the presence of NaHCO₃–Na₂SiF₆ buffer solution. The resulting cobalt catalyst with an average particle size less than 2 nm exhibited a turnover frequency of 0.023 per second per cobalt in photocatalytic water oxidation. X-ray absorption results suggested a unique nanocubane structure, where 13 cobalt atoms fully coordinated with oxygen in an octahedral arrangement to form 8 Co₄O₄ cubanes, which may be responsible for the exceptionally high OER activity

New method for determining total calcium content in tissue applied to skeletal muscle with and without calsequestrin

We describe a new method for determining the concentration of total Ca in whole skeletal muscle samples ([Ca] in units of mmoles/kg wet weight) using the Ca-dependent UV absorbance spectra of the Ca chelator BAPTA (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid). Muscle tissue was homogenized in a solution containing 0.15 mM BAPTA and 0.5% sodium dodecyl sulfate (to permeabilize membranes and denature proteins) and then centrifuged. The solution volume was adjusted so that BAPTA captured essentially all of the Ca. [Ca] was obtained with Beer's law from the absorbance change produced by adding 1 mM EGTA to capture Ca from BAPTA. Results from mouse, rat, and frog muscles were reasonably consistent with results obtained using other methods for estimating total [Ca] in whole muscles and in single muscle fibers. Results with external Ca removed before determining [Ca] indicate that most of the Ca was intracellular, indicative of a lack of bound Ca in the extracellular space. In both fast-twitch (extensor digitorum longus, EDL) and slow-twitch (soleus) muscles from mice, [Ca] increased approximately linearly with decreasing muscle weight, increasing approximately twofold with a twofold decrease in muscle weight. This suggests that the Ca concentration of smaller muscles might be increased relative to that in larger muscles, thereby increasing the specific force to compensate for the smaller mass. Knocking out the high capacity Ca-binding protein calsequestrin (CSQ) did not significantly reduce [Ca] in mouse EDL or soleus muscle. However, in EDL muscles lacking CSQ, muscle weights were significantly lower than in wild-type (WT) muscles and the values of [CaT]WM were, on average, about half the expected WT values, taking into account the above [Ca] versus muscle weight relationship. Because greater reductions in [Ca] would be predicted in both muscle types, we hypothesize that there is a substantial increase in Ca bound to other sites in the CSQ knockout muscles