Hybrid Problem Solving

This chapter evaluates how the close juxtaposition of civic and noncivic in hybrid civic action provides better ways to discern whether or not, and how, nonprofits express the will of people in their immediate locale, and whether or not they pose an effective alternative to governmental action, as some commentators argue. All that should help clarify how civic action really works. The chapter focuses mostly on a locally prominent and successful, nonprofit affordable housing developer, Housing Solutions for Los Angeles (HSLA). It then compares HSLA briefly with efforts by a Tenants of South Los Angeles (ISLA) committee to administer the housing provisions of the community benefits agreement (CBA) that ISLA's campaign won from the Manchester apartments developer. This was a different kind of hybrid. ISLA's affordable housing work for the community ultimately was both financed and constrained by a big, for-profit real estate developer — the Manchester property owner.

The simultaneous analysis of mesenchymal stem cells and early osteocytes accumulation in osteoarthritic femoral head sclerotic bone

Objective OA subchondral bone is a key target for therapy development. Osteocytes, the most abundant bone cell, critically regulate bone formation and resorption. Their progenitors, mesenchymal stem cells (MSCs), display altered behaviour in osteoarthritic subchondral bone. This study investigated the relationships between native osteocytes and native MSCs in osteoarthritic femoral heads. Methods To avoid culture manipulations, a bone treatment procedure was developed to simultaneously obtain pure osteocyte-enriched fragments and matched native CD45-CD271+ MSCs. Gene expression in osteocytes and MSCs was compared between healthy and OA bone and selected molecules were examined by immunohistochemistry in relation to OA tissue pathology. Cell sorting and standard trilineage differentiation assays were employed to test OA MSC functionality. Results Native osteocyte enrichment was confirmed histologically and by higher-level osteocyte maturation transcripts expression, compared with purified MSCs. Compared with healthy bone, native OA osteocytes expressed 9- and 4-fold more early/embedding osteocyte molecules E11 and MMP14, and 6-fold more osteoprotegerin (P<0.01). CD271+ MSCs accumulated in the regions of bone sclerosis (9-fold, P<0.0001) in close juxtaposition to trabeculae densely populated with morphologically immature E11-positive osteocytes (medians of 76% vs 15% in non-sclerotic areas, P<0.0001), and osteoblasts. Gene expression of OA MSCs indicated their bone formation bias, with retained multipotentiality following culture-expansion. Conclusions In human late-stage OA, osteogenically-committed MSCs and adjacent immature osteocytes exhibit a marked accumulation in sclerotic areas. This hitherto unappreciated MSC-early osteocyte axis could be key to understanding bone abnormalities in OA and represents a potential target for novel therapy development in early disease.

Greetings and compliments or street harassment? Competing evaluations of street remarks in a recorded collection

In this article I evaluate competing discourses about the meaning of street remarks – the remarks men make to unacquainted women passing on the street – in 1000 comments posted to a YouTube video of street remarks recorded in New York City in 2014. One discourse prominent in the comments posted to the video defends the remarks as civil talk, highlighting the literal meanings of remarks such as ‘Have a nice evening’. A second, less frequent, discourse characterizes these encounters and utterances as sexual harassment, citing men’s ostensible sexual intentions and personal experience. I find that (a) difficulties in articulating the ways in which street remarks are injurious may veil their harm, thus contributing to the perpetuation of male domination of women in public spaces, and (b) the close juxtaposition of explicitly misogynistic comments with interpretations of the street remarks as civil casts doubt on the sincerity of such interpretations.

Mechanical output impedance of the lung determined from cardiogenic oscillations

The beating heart naturally oscillates the lung because of the close juxtaposition between these organs producing cardiogenic oscillations in flow that can be measured at the mouth when the glottis is open. Correspondingly, if the mouth is occluded, the same phenomenon produces cardiogenic pressure oscillations that can be measured just distal to the site of occlusion. The Fourier-domain ratio of these oscillations in pressure and flow constitutes what we call cardiogenic respiratory impedance (Zc). We calculated Zc between about 1.5 and 10 Hz in relaxed normal subjects at functional residual capacity with open glottis. Zc was insensitive to heart rate changes induced by exercise and had an imaginary part close to zero at all frequencies investigated. Its real part was similar to or smaller than resistance determined by the forced oscillation technique. We speculate that Zc measures the flow resistance of the central and upper airways of the lung. Zc may be useful as a means of obtaining information about lung mechanics without the need for an external source of flow perturbations.

Gonadal mesoderm and fat body initially follow a common developmental path in Drosophila

During gastrulation, the Drosophila mesoderm invaginates and forms a single cell layer in close juxtaposition to the overlying ectoderm. Subsequently, particular cell types within the mesoderm are specified along the anteroposterior and dorsoventral axes. The exact developmental pathways that guide the specification of different cell types within the mesoderm are not well understood. We have analyzed the developmental relationship between two mesodermal tissues in the Drosophila embryo, the gonadal mesoderm and the fat body. Both tissues arise from lateral mesoderm within the eve domain. Whereas in the eve domain of parasegments 10–12 gonadal mesoderm develops from dorsolateral mesoderm and fat body from ventrolateral mesoderm, in parasegments 4–9 only fat body is specified. Our results demonstrate that the cell fate decision between gonadal mesoderm and fat body identity within dorsolateral mesoderm along the anteroposterior axis is determined by the combined actions of genes including abdA, AbdB and srp; while srp promotes fat body development, abdA allows gonadal mesoderm to develop by repressing srp function. Furthermore, we present evidence from genetic analysis suggesting that, before stage 10 of embryogenesis, gonadal mesoderm and the fat body have not yet been specified as different cell types, but exist as a common pool of precursor cells requiring the functions of the tin, zfh-1 and cli genes for their development.

Differential flux through the quinate and shikimate pathways. Implications for the channelling hypothesis

The qutC gene encoding dehydroshikimate dehydratase has been constitutively overexpressed in Aspergillus nidulans from a range of 1-30-fold over the normal wild-type level. This overexpression leads to impaired growth in minimal medium which can be alleviated by the addition of aromatic amino acids to the medium. Overexpression of the qutC gene in mutant strains lacking protocatechuic acid (PCA) oxygenase leads to the build up of PCA in the medium, which can be measured by a simple assay. Measuring the rate of production of PCA in strains overproducing dehydroshikimate dehydratase and correlating this with the level of overproduction and impaired ability to grow in minimal medium lacking aromatic amino acids leads to the conclusion that (a) the metabolites 3-dehydroquinate and dehydroshikimate leak from the AROM protein at a rate comparable with the extent of flux catalysed by the AROM protein, (b) the AROM protein has a low-level channelling function probably as a result of the close juxtaposition of five active sites and (c) this channelling function is only physiologically significant under non-optimal conditions of nutrient supply and oxygenation, when the organism is in situ in its natural environment.

Ultrastructural Observations on Induced Retraction of the Reticulopodial Network of Allogromia SP. (Foraminifera)

Allogromia sp. (strain N.F. Lee) provides a convenient model system for studying intracellular transport. We have been examining ultrastructural changes which occur in the reticulopodial network (RN) and cell body (CB) of Allogromia at various stages in the retraction response stimulated by 0.4M MgCl2 solution. As retraction proceeds, microtubules (MT) disassemble and form areas of regularly packed cytoplasm (TP-tigroid patterning) resembling vinca alkaloid induced paracrystals of tubulin. TP is first seen in the RN, and later in the CB. TP consists of dark filamentous material 12.5 nm in width separated by a light spacing of 8 nm when plane of section gives a perfect repeat pattern (arrow-fig. 6). TP may fill the entire profile of a reticulopod and in early stages of retraction is seen in close juxtaposition to MT. In the CB, TP occurs in patches 0.3-2.0 μm in diameter. TP is seen with great frequency in retracting Allogromia, but also, it can be seen occasionally in animals with fully extended RN.