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Los Angeles’s Transit-Oriented Communites Program: Challenges and Opportunities
In recent years, municipalities throughout California have struggled to meet housing needs, and construction of new housing units in the state has not kept apace of demand, resulting in increased housing costs that rank among the highest in the nation. At the same time, California faces pressure to achieve ambitious greenhouse gas (GHG) reduction goals in the relatively near term. Meeting those goals will require significant decreases in transportation sector emissions, which represent about 40 percent of the state’s GHG emissions. Particularly impacted by both the affordability and climate change crises are low-income Californians, whose communities suffer disproportionate impacts from lack of housing availability and vulnerability to climate change—and who also are California’s most reliable transit riders.Lawmakers seeking to tackle both housing and greenhouse gas reduction goals have turned to transit-oriented development programs—zoning programs that promote increased housing density close to mass transit options like bus and rail—as one way to address both issues. This paper focuses on one such transit-oriented development program, the City of Los Angeles’ Transit Oriented Communities Affordable Housing Incentive Program (TOC Program). The TOC Program offers density and other development incentives to projects within a half-mile radius of major transit stops, in exchange for developer commitments to provide a set percentage of deed-restricted affordable housing units within those projects.The TOC Program has been a major driver of affordable housing production in the City of Los Angeles since its adoption in late 2017, but certain structural and legal constraints may be impeding its full capacity to augment affordable housing supply. This paper explores those potential constraints and offers recommendations to increase the program’s efficacy. It also explores how the program can provide data and lessons learned to lawmakers considering similar inclusionary transit-oriented development programs within their jurisdictions, or even at the state level
Effect of gonococcal lipooligosaccharide variation on human monocytic cytokine profile
BACKGROUND: Neisseria gonorrhoeae is an obligate human pathogen that causes significant worldwide morbidity. N. gonorrhoeae expresses lipooligosaccharide (LOS), a phase variable molecule that plays an important role during pathogenesis of the organism. Alteration in the structure of gonococcal LOS correlates with altered disease presentation. In addition, LOS sialylation occurs readily in vivo, though the role of this sialylation during disease is unknown. RESULTS: Challenge of human monocytes with purified LOS preparations isolated from strains expressing distinct structurally defined LOSs resulted in identical production of the proinflammatory cytokines tumor necrosis factor alpha (TNFα) and interleukin-12 (IL-12). Similar results were seen when monocytes were challenged with either live or gentamicin-killed whole cell gonococcal variants expressing these LOS structures, although greater cytokine production was observed in comparison with challenge by purified LOS. Challenge of a human primary monocyte model with distinct LOS variants resulted in similar production of TNFα, IL-12, interleukin-10 (IL-10), and interleukin-8 (IL-8). A cytokine array was employed to allow measurement of a broad range of cytokines in samples challenge with gonococcal LOS variants as well as variants expressing sialylated LOS. Challenge of primary monocytes with sialylated gonococci was shown to elicit the production of more MCP-2 (monocyte chemoattractant protein-2) in comparison with challenge by unsialylated gonococci. CONCLUSION: We demonstrated that while alterations in the carbohydrate moiety of LOS do not impact the production of most cytokines by human monocytes, whole-cell bacterial challenge is more stimulatory than challenge with purified LOS, implying that other gonococcal cell surface antigens are important for the elicitation of cytokines. Challenge with gonococci expressing sialylated LOS resulted in elicitation of more of the chemokine MCP-2 from challenged cells in comparison with gonococci expressing unsialylated LOS. As MCP-2 is an important chemoattractant, this indicates that in vivo sialylation may play an important role during the pathogenesis of N. gonorrhoeae
Relationship Between Stages of Change and HPV Vaccine Attitudes and Beliefs in Baccalaureate Nursing Students
The purpose of this study was to: (a) determine if there is a relationship between attitudes/beliefs about Human papillomavirus (HPV) vaccination and stages of change and (b) investigate gender differences in attitudes/beliefs and stages of change in undergraduate baccalaureate nursing students. The study employs a cross-sectional and descriptive correlational design and it was guided by the Trans-theoretical Model of Change (TMC). The convenience sample was comprised of 131 participants at a large urban public university in Midwest United States. Data were collected with online surveys distributed via university email. A positive, moderate relationship was found between HPV vaccination attitudes/beliefs and stage of change (r=.36, p\u3c.001). Attitudes/beliefs and readiness to change were measured using multiple regression. An independent t-test was used to determine difference in male and female mean belief and attitude scores. Results show that those with more favorable attitudes/beliefs about HPV vaccination, as well as those who felt supported by others regarding obtaining the vaccine, were more likely to either be in the process of getting vaccinated or had already been vaccinated. Also, although there is no statistical difference in attitudes/beliefs about the HPV vaccine between males and females, males were less likely to have made efforts to be vaccinated compared with females (t= -2.99, p=.003). Therefore, it is possible that there is a gender disparity in knowledge about the vaccine or how to obtain it. The findings warrant further investigation as to what prevents males from being vaccinated
Sparse annotation strategies for segmentation of short axis cardiac MRI
Short axis cardiac MRI segmentation is a well-researched topic, with
excellent results achieved by state-of-the-art models in a supervised setting.
However, annotating MRI volumes is time-consuming and expensive. Many different
approaches (e.g. transfer learning, data augmentation, few-shot learning, etc.)
have emerged in an effort to use fewer annotated data and still achieve similar
performance as a fully supervised model. Nevertheless, to the best of our
knowledge, none of these works focus on which slices of MRI volumes are most
important to annotate for yielding the best segmentation results. In this
paper, we investigate the effects of training with sparse volumes, i.e.
reducing the number of cases annotated, and sparse annotations, i.e. reducing
the number of slices annotated per case. We evaluate the segmentation
performance using the state-of-the-art nnU-Net model on two public datasets to
identify which slices are the most important to annotate. We have shown that
training on a significantly reduced dataset (48 annotated volumes) can give a
Dice score greater than 0.85 and results comparable to using the full dataset
(160 and 240 volumes for each dataset respectively). In general, training on
more slice annotations provides more valuable information compared to training
on more volumes. Further, annotating slices from the middle of volumes yields
the most beneficial results in terms of segmentation performance, and the
apical region the worst. When evaluating the trade-off between annotating
volumes against slices, annotating as many slices as possible instead of
annotating more volumes is a better strategy
Bispezifische Antikörper in der Immuntherapie der Akuten Myeloischen Leukämie: Charakterisierung eines TIM3/CD3-Konstrukts in Hinblick auf Resistenzmechanismen
Home death for children dying in six European countries
Aim: Guidelines on pediatric palliative care underline that care at the end of life of chronically ill children should preferably be provided in the child’s home situation. Till present, no European data at population level are available for place of death of children. The aim of this study was to compare proportions of home death for children in six European countries and investigate relation between place of death and sociodemographic and clinical factors. Method: Data were collected from death certificates of all deceased children aged 1-17 in Belgium (BE), the Netherlands (NL), Norway (NO), England (E), Wales (W) (2003) and Italy (IT) (2002). Gender, cause (cancer, natural non-cancer and external) and place of death (home vs. outside home) and sociodemographic factors (socio-economic status (SES), degree of urbanization and number of hospital beds in the area) were included in the analyses. Data were analyzed using frequencies and multivariate logistic regression. Results:
A total of 3.187 deaths were included in the analyses, 534 (16,8%) died from cancer. The proportion of home deaths was 19,6% (IT), 20,5% (E), 20,6% (W), 21,0% (NO), 23,8% (BE) and 28,6% (NL). Home death was more likely for children dying from cancer in BE, NL, E and W, for children with high SES in BE, in areas with low number of hospital beds in IT, and for boys in NL. Conclusion: The proportion of home deaths for children differs between studied countries. In most, but not all, countries children dying from cancer had better odds of dying at home than those not dying from cancer. Although acknowledging the influence of culture in the differences, studying care provisions in countries with higher proportions of home deaths, particularly in chronically ill children, can be helpful to identify factors facilitating terminally ill children to die at home. Early involvement of palliative care and equal access to these services can be important in this context. Funding: IWT-Flanders
Partitioning a 2-edge-coloured graph of minimum degree into three monochromatic cycles
Lehel conjectured in the 1970s that every red and blue edge-coloured complete
graph can be partitioned into two monochromatic cycles. This was confirmed in
2010 by Bessy and Thomass\'e. However, the host graph does not have to be
complete. It it suffices to require that has minimum degree at least
, where is the order of , as was shown recently by Letzter,
confirming a conjecture of Balogh, Bar\'{a}t, Gerbner, Gy\'arf\'as and
S\'ark\"ozy. This degree condition is asymptotically tight.
Here we continue this line of research, by proving that for every red and
blue edge-colouring of an -vertex graph of minimum degree at least , there is a partition of the vertex set into three monochromatic cycles.
This approximately verifies a conjecture of Pokrovskiy and is essentially
tight
Aechmea distichantha (Bromeliaceae) Epiphytes, Potential New Habitat for Aedes Aegypti and Culex quinquefasciatus (Diptera: Culicidae) Collected in the Province of Tucumán, Northwestern Argentina
Larval habitats of Aedes (Stegomyia) aegypti (Linnaeus) and Culex (Culex) quinquefasciatus Say in the epiphyte Aechmea distichantha Lemaire (Poales: Bromeliaceae), were found and described both in semi-urban and rural localities of piedmont forest of the subtropical mountainous Yungas rainforest in the province of Tucuman, northwestern Argentina. This finding suggests that these anthropophilic disease vectors have achieved a degree of introduction and adaptation to the primitive forest, and that the bromeliad, which possesses phytotelmata, has an epidemiological role in providing natural water containers for the breeding of mosquito vectors.Aechmea distichantha Lemaire (Poales: Bromeliaceae) epĂfita se describe como hábitat larval de Aedes (Stegomyia) aegypti (Linnaeus) y Culex (Culex) quinquefasciatus Say halladas tanto en localidades semi-urbanas como rurales de los bosques de piedemonte de la selva subtropical montañosa de las Yungas de la provincia de Tucumán, noroeste de Argentina. Este hallazgo sugiere que estos vectores antropofĂlicos han alcanzado cierto grado de introduction y adaptation al bosque primitivo, y que la bromelia (fitotelmata), tiene un papel epidemiolĂłgico en el suministro de contenedores naturales de agua para la crĂa de mosquitos vectores.Fil: Stein, Marina. Universidad Nacional del Nordeste. Instituto de Medicina Regional. Area de Entomologia; ArgentinaFil: Dantur Juri, Maria Julia. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto Superior de EntomologĂa; Argentina. Universidad Nacional de Chilecito; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Oria, Griselda I.. Universidad Nacional del Nordeste. Instituto de Medicina Regional. Area de Entomologia; ArgentinaFil: Ramirez, Patricia Graciela. Universidad Nacional del Nordeste. Instituto de Medicina Regional. Area de Entomologia; Argentin
Embedded Printing of Hydrogels and Watery Suspensions of Cells in Patterned Granular Baths
Bioprinting within support media has emerged as the superior alternative to conventional extrusion printing. Not only because it allows for more freedom over the shapes that can be printed but also because it allows for the printing of inks that would not retain shape fidelity in freeform deposition such as watery liquids. Apart from functioning as mechanical support during embedded printing, hydrogel microparticle support media can provide the unique advantage of offering distinct chemotactic cues to cells printed in the baths by varying the composition of the hydrogel microparticles. There is great potential in compartmentalized granular baths consisting of different hydrogel particle materials in the field of tissue engineering, as these allow for the local inclusion of properties or cues to guide tissue development. In this work, we present a method to create compartmentalized embedding baths by printing multiple granular hydrogel materials that are widely used in tissue engineering. After adapting the volume fraction (φp) of the particles in the bath, we print within them using both inks composed of hydrogel or of cells and other particles suspended in watery liquid. Our process consists of the following three steps: First, the hydrogel microparticles are packed at a φp that allows them to be extruded while being reversibly jammed, facilitating the localized deposition of the granular media to form a compartmentalized bath. Second, each granular media is deposited in succession to create a packed suspension compartment, and by adding liquid post deposition, φp is reduced to allow for embedded printing. Finally, we demonstrate the printing of multiple inks within the compartmentalized embedding bath and highlight the distinct differences between using inks composed of hydrogels or inks composed of particles suspended in watery liquid. This approach combines the advantages of embedded printing through the use of granular media with the added ability to pattern multiple bioactive granular materials to locally affect the behavior of cells printed within the bath. We expect that this workflow will allow researchers to create spatially compartmentalized, customized bioactive embedding baths that allow for the embedded printing of inks composed of hydrogels, cells, and other particles adapted to their need
Towards Vascularized Tissue Blocks Using a Suspension Bioprinted Blood Vessel
In order for engineered tissue grafts and eventually organs to successfully integrate in a clinical setting, a functional vascular network is imperative. Without vasculature, the tissue constructs cannot receive nutrients essential for their survival, but also lack the stimuli that determine the tissue’s biophysical properties i.e. cell fate determination, cell to cell junctions, and cell orientation. In order for the vascular network to functionally connect to the patient, a hierarchical organization, resembling the vascular tree, is important. From previous studies it is known that fluid flow is a crucial component in controlling the formation of the vascular tree, and that the organization of the vascular network can be further controlled using gradients of angiogenic growth factors such as VEGF. By utilizing spheroid bioprinting within a microgel suspension, an artificial vessel structure was assembled. The deposited spheroids maintained viability and fused over time into perfusable vessels.The subsequent formation of small-diameter vascular structures and capillaries was regulated by an on-demand flow through the bioprinted vessel, resulting in controllable fluid flow shear stresses. Furthermore, VEGF was spatially patterned in the tissue block by locally doping the suspension with growth factor releasing microparticles. By varying both these stimuli, the location of vascular sprout formation and subsequent growth of the new vascular structures could be influenced. This spheroid 3D bioprinting platform offers a dynamic, customizable and accurate method to trigger and control the process of angiogenesis in vitro. By stimulating an artificial blood vessel with controlled fluid flow and growth factor gradients, a vascular complex vascular network can be produced and modulated. The combination of this approach with a gradual replacement of the microgel suspension with cells, can pave the way for the production of vascularized tissue blocks
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