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Chapter contributors offer historical and contemporary perspectives on equitable communities, the affordable housing crisis, and the public policies that can generate needed change. A Brandeis University professor describes disparities across the nation’s neighborhoods and presents findings from the Child Opportunity Index. A senior fellow at Urban Institute addresses the risks and benefits of zoning and land use reforms, while fair housing advocate Former president of the Inclusive Communities Project describes ways to ensure that people have genuine housing choice. Executive director of come dream. come build. draws on his experience as a nonprofit housing developer to explain how low-income people on the southern U.S. border can build home equity. Executive director of the Jackson Medical Mall Foundation describes this enterprise, which combines healthcare, community development (including affordable home ownership), arts and culture, and innovation and technology to renew and strengthen a Jackson, Miss., community.

Research on the African cheetah (Acinonyx jubatus) exhibits strong geographical biases, with most studies taking place within a few, well‐studied populations. Here, we provide the first insights into the status and distribution of a globally important cheetah population in the 50,000 km2 Ruaha‐Rungwa landscape in southern Tanzania. We employed data from four methods (systematic camera trap surveys, sign surveys, community camera trapping, and observations by photo‐tourism guides) to improve knowledge of this understudied population. Our findings indicate that cheetah are widespread across the landscape, although they appear to exist at relatively low population densities, likely primarily due to biotic factors. Our surveys revealed an extension of confirmed geographical range of the species and provide some of the first evidence that miombo woodlands may be an important habitat for cheetah across its eastern African range. We employ these findings to identify research priorities for the species elsewhere in the region. Community camera trapping revealed that cheetah are using unprotected areas, although rarely. Finally, we show that collaborations with tourism operators can be employed to monitor cheetah populations, but also identify limitations of this method. Our results have implications for conservation of the species both in southern Tanzania and across its African range.

The development of site‐selective chemistry targeting the canonical amino acids enables the controlled installation of desired functionalities into native peptides and proteins. Such techniques facilitate the development of polypeptide conjugates to advance therapeutics, diagnostics, and fundamental science. We report a versatile and selective method to functionalize peptides and proteins through free‐radical‐mediated dechalcogenation. By exploiting phosphine‐induced homolysis of the C−Se and C−S bonds of selenocysteine and cysteine, respectively, we demonstrate the site‐selective installation of groups appended to a persistent radical trap. The reaction is rapid, operationally simple, and chemoselective. The resulting aminooxy linker is stable under a variety of conditions and selectively cleavable in the presence of a low‐oxidation‐state transition metal. We have explored the full scope of this reaction using complex peptide systems and a recombinantly expressed protein., Functionalization of peptides and proteins through the trapping of peptide radical species is described. This novel and versatile strategy exploits the process of desulfurization and deselenization of cysteine and selenocystine residues to enable the site‐selective installation of a broad range of groups appended to a persistent radical trap.

Post-translational modifications (PTMs) enhance the repertoire of protein function and mediate or influence the activity of the majority of cellular processes. The preparation of site-specifically and homogeneously modified proteins to apply as tools to understand the biological role of PTMs is a challenging task. Herein, we describe a visible-light-mediated desulfurative C(sp3)-C(sp3) bond forming reaction that enables the site-selective installation of Ne-modified sidechains into peptides and proteins of interest. Rapid, operationally simple and tolerant to ambient atmosphere, we demonstrate the installation of a range of lysine (Lys) PTMs into model peptide systems and showcase the potential of this technology by site- selectively installing an NeAc sidechain into recombinantly expressed ubiquitin (Ub).

Peptide ligation techniques enable the controlled chemical synthesis of native and engineered proteins, including examples that display site-specific post-translational modifications (PTMs) and non-proteinogenic functionality. Diselenide-selenoester ligation (DSL) is a recent addition to the synthetic methodology that offers several advantages over existing strategies. The standard DSL reaction involves the additive-free ligation of a peptide carrying an N-terminal selenocysteine (Sec) residue with a fragment bearing a C-terminal selenoester. This operationally simple ligation proceeds rapidly at sterically hindered junctions and is efficient across a broad pH range. The incorporation of deselenization and oxidative deselenization techniques into the DSL protocol enables conversion of the Sec residue at the ligation site to alanine (Ala) and serine (Ser), respectively, thus enhancing the scope and versatility of the method. In this chapter, we describe the application of DSL to the one-pot chemical synthesis of proteins via both two-component and three-component ligation pathways.

Polyproline sequences are highly abundant in prokaryotic 10 and eukaryotic proteins, where they serve as key components of 11 secondary structure. To date, construction of the proline?proline motif 12 has not been possible owing to steric congestion at the ligation junction, 13 together with an n ? ?* electronic interaction that reduces the 14 reactivity of acylated proline residues at the C-terminus of peptides. 15 Here, we harness the enhanced reactivity of prolyl selenoesters and a 16 trans-?-selenoproline moiety to access the elusive proline?proline 17 junction for the ?rst time through a diselenide?selenoester ligation? 18 deselenization manifold. The e?cient nature of this chemistry is 19 highlighted in the high-yielding one-pot assembly of two proline-rich 20 polypeptide targets, submaxillary gland androgen regulated protein 3B 21 and lumbricin-1. This method provides access to the most challenging of ligation junctions, thus enabling the construction of 22 previously intractable peptide and protein targets of increasing structural complexity.

BackgroundDue to the increased degree of modulation and complexity of volumetric-modulated arc therapy (VMAT) plans, it is necessary to have a pre-treatment patient-specific quality assurance (QA) programme. The gamma index is commonly used to quantitatively compare two dose distributions. In this study we investigated the sensitivity of single- and multi-gamma criteria techniques to detect multileaf collimator (MLC) positioning errors using the Varian TrueBeam Electronic Portal Imaging DeviceTM (EPID) dosimetry and the ArcCHECKTM device.Materials and methodsAll active MLC positions of seven intact prostate patients VMAT plans were randomly changed with a mean value of 0.25, 0.5, 1 and 2 mm and a standard deviation of 0.1 mm on 25, 50, 75 and 100% of the control points. The change in gamma passing rates of six gamma criteria of 3%/3 mm, 3%/2 mm, 3%/1 mm, 2%/2 mm, 2%/1 mm and 1%/1 mm were analysed individually (single-gamma criterion) and as a group (multi-gamma criteria) as a function of the simulated errors. We used the improved and global gamma calculation algorithms with a low dose threshold of 10% in the EPID and ArcCHECK software, respectively. The changes in the planning target volume dose distributions and the organs at risk due to the MLC positioning errors were also studied.ResultsWhen 25, 50, 75 and 100% of the control points were modified by the introduction of the simulated errors, the smallest detectable errors with the EPID were 2, 1, 0.5 and 0.5 mm, respectively, using the multi-gamma criteria technique. Similarly for the single-gamma criteria technique errors as small as 2, 1, 1 and 1 mm applied to 25, 50, 75 and 100% of the control points, respectively, were detectable using a 2%/2 mm criterion. However, the smallest detectable errors with the ArcCHECK when using the multi-gamma criteria technique were 2, 2 and 1 mm when MLC errors were applied on 50, 75 and 100% of the control points. When only 25% of the control points were affected the ArcCHECK were unable to detect any of the errors applied. No noticeable difference was observed in the sensitivity using the single- or the multi-gamma criteria techniques with the ArcCHECK.ConclusionThe Varian TrueBeam EPID dosimetry shows a higher sensitivity in detecting MLC positioning errors compared with the ArcCHECK regardless of using the single- or the multi-gamma criteria techniques. Higher sensitivity was observed using the multi-gamma criteria technique compared with the single-criterion technique when using the EPID.

Despite the unique chemical properties of selenocysteine (Sec), ligation at Sec is an under-utilized methodology for protein synthesis. We describe herein an unprecedented protocol for the conversion of Sec to serine (Ser) in a single, high-yielding step. When coupled with ligation at Sec, this transformation provides a new approach to programmed ligations at Ser residues. This new reaction is compatible with a wide range of functionality, including the presence of unprotected amino acid side chains and appended glycans. The utility of the methodology is demonstrated in the rapid synthesis of complex glycopeptide fragments of the epithelial glycoproteins MUC5AC and MUC4 and through the total synthesis of the structured, cysteine (Cys)-free protein eglin C.

Peptide ligation chemistry has revolutionized protein science by facilitating access to synthetic proteins. Here, we describe the development of additive-free ligation-deselenization chemistry at β-selenoaspartate and γ-selenoglutamate that enables the generation of native polypeptide products on unprecedented timescales. The deselenization step is chemoselective in the presence of unprotected selenocysteine, which is highlighted in the synthesis of selenoprotein K. The power of the methodology is also showcased through the synthesis of three tick-derived thrombin-inhibiting proteins, each of which were assembled, purified, and isolated for biological assays within a few hours. The methodology described here should serve as a powerful means of accessing synthetic proteins, including therapeutic leads, in the future.

This literature review focuses on the e-use of video in teacher initial and continuing professional development. There is evidence that video technology used synchronously, and particularly asynchronously, can extend the quantity and quality of classroom observation experience, which in turn supports the development of observation, analysis and reflection in viewers. Theorising on these gains, the authors describe how the linking of theory to practice, the development of pedagogical language and collaborative learning through communities of practice might all be related to video-enhanced teacher education. Claims for gains in codified subject knowledge are less convincing.

The convergent assembly of peptide fragments by native chemical ligation has revolutionized the way in which proteins can be accessed by chemical synthesis. A variation of native chemical ligation involves the reaction of peptides bearing an N-terminal selenocysteine residue with peptide thioesters, which proceeds through the same mechanism as the parent reaction. This transformation was first investigated in 2001 for the installation of selenocysteine into peptides and proteins via ligation chemistry. The recent discovery that selenocysteine residues within peptides can be chemoselectively deselenized without the concomitant desulfurization of cysteine residues has led to renewed interest in ligation chemistry at selenocysteine. This review outlines the use of selenocysteine in ligation chemistry as well as recent investigations of chemoselective ligation-deselenization chemistry at other selenol-derived amino acids that have the potential to greatly expand the number of targets that can be accessed by chemical synthesis.

Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human-wildlife coexistence across large multiple-use landscapes.

Serverless computing has emerged as a new compelling paradigm for the deployment of applications and services. It represents an evolution of cloud programming models, abstractions, and platforms, and is a testament to the maturity and wide adoption of cloud technologies. In this chapter, we survey existing serverless platforms from industry, academia, and open-source projects, identify key characteristics and use cases, and describe technical challenges and open problems.