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Caloric restriction blocks neuropathology and motor deficits in Machado–Joseph disease mouse models through SIRT1 pathway

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Caloric restriction blocks neuropathology and motor deficits in Machado–Joseph disease mouse models through SIRT1 pathway Cunha-Santos, Janete; Duarte-Neves, Joana; Carmona, Vitor; Pereira de Almeida, Luís; Cavadas, Cláudia; Guarente, Leonard Pershing Machado–Joseph disease (MJD) is a neurodegenerative disorder characterized by an abnormal expansion of the CAG triplet in the ATXN3 gene, translating into a polyglutamine tract within the ataxin-3 protein. The available treatments only ameliorate symptomatology and do not block disease progression. In this study we find that caloric restriction dramatically rescues the motor incoordination, imbalance and the associated neuropathology in transgenic MJD mice. We further show that caloric restriction rescues SIRT1 levels in transgenic MJD mice, whereas silencing SIRT1 is sufficient to prevent the beneficial effects on MJD pathology. In addition, the re-establishment of SIRT1 levels in MJD mouse model, through the gene delivery approach, significantly ameliorates neuropathology, reducing neuroinflammation and activating autophagy. Furthermore, the pharmacological activation of SIRT1 with resveratrol significantly reduces motor incoordination of MJD mice. The pharmacological SIRT1 activation could provide important benefits to treat MJD patients.

Feminism and the Future of Library Discovery

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Feminism and the Future of Library Discovery Sadler, Bess; Bourg, Mary C This paper discusses the various ways in which the practices of libraries and librarians influence the diversity (or lack thereof) of scholarship and information access. We examine some of the cultural biases inherent in both library classification systems and newer forms of information access like Google search algorithms, and propose ways of recognizing bias and applying feminist principles in the design of information services for scholars, particularly as libraries re­invent themselves to grapple with digital collections.

The Library Concierge Project at Stanford University

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The Library Concierge Project at Stanford University Bourg, Mary C To meet the challenge of ensuring that library staff and scholars/patrons are aware of the full range of resources and services offered through the library, the Stanford University Libraries initiated a Library Concierge Project in November of 2011. This article describes the program and provides an assessment of how well the Library Concierge Project has met its goals of promoting a service-focused culture and educating staff. A description of the concierge concept in action is also provided, along with anecdotal evidence of the impact of the project on supported scholars.

Comparative genomics and transcriptomics of Pichia pastoris

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Comparative genomics and transcriptomics of Pichia pastoris Priest, Margaret; Borowsky, Jonathan; Young, Sarah K.; Love, Kerry R.; Whittaker, Charles A; Love, John C; Wu, Jie; Ma, Duanduan; Shah, Kartik A; Bartlett, Mary Catherine; Leeson, Rachel Background Pichia pastoris has emerged as an important alternative host for producing recombinant biopharmaceuticals, owing to its high cultivation density, low host cell protein burden, and the development of strains with humanized glycosylation. Despite its demonstrated utility, relatively little strain engineering has been performed to improve Pichia, due in part to the limited number and inconsistent frameworks of reported genomes and transcriptomes. Furthermore, the co-mingling of genomic, transcriptomic and fermentation data collected about Komagataella pastoris and Komagataella phaffii, the two strains co-branded as Pichia, has generated confusion about host performance for these genetically distinct species. Generation of comparative high-quality genomes and transcriptomes will enable meaningful comparisons between the organisms, and potentially inform distinct biotechnological utilies for each species. Results Here, we present a comprehensive and standardized comparative analysis of the genomic features of the three most commonly used strains comprising the tradename Pichia: K. pastoris wild-type, K. phaffii wild-type, and K. phaffii GS115. We used a combination of long-read (PacBio) and short-read (Illumina) sequencing technologies to achieve over 1000X coverage of each genome. Construction of individual genomes was then performed using as few as seven individual contigs to create gap-free assemblies. We found substantial syntenic rearrangements between the species and characterized a linear plasmid present in K. phaffii. Comparative analyses between K. phaffii genomes enabled the characterization of the mutational landscape of the GS115 strain. We identified and examined 35 non-synonomous coding mutations present in GS115, many of which are likely to impact strain performance. Additionally, we investigated transcriptomic profiles of gene expression for both species during cultivation on various carbon sources. We observed that the most highly transcribed genes in both organisms were consistently highly expressed in all three carbon sources examined. We also observed selective expression of certain genes in each carbon source, including many sequences not previously reported as promoters for expression of heterologous proteins in yeasts. Conclusions Our studies establish a foundation for understanding critical relationships between genome structure, cultivation conditions and gene expression. The resources we report here will inform and facilitate rational, organism-wide strain engineering for improved utility as a host for protein production.

Kawasaki Dynamics in Continuum: Micro- and Mesoscopic Descriptions

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Kawasaki Dynamics in Continuum: Micro- and Mesoscopic Descriptions Berns, Christoph; Kondratiev, Yuri; Kozitsky, Yuri; Kutovyi, Oleksandr The dynamics of an infinite system of point particles in ℝ[superscript d], which hop and interact with each other, is described at both micro- and mesoscopic levels. The states of the system are probability measures on the space of configurations of particles. For a bounded time interval [0,T), the evolution of states μ[subscript 0]↦μ[subscript t] is shown to hold in a space of sub-Poissonian measures. This result is obtained by: (a) solving equations for correlation functions, which yields the evolution k[subscript 0]↦k[subscript t], t∈[0,T), in a scale of Banach spaces; (b) proving that each k[subscript t] is a correlation function for a unique measure μ[subscript t]. The mesoscopic theory is based on a Vlasov-type scaling, that yields a mean-field-like approximate description in terms of the particles’ density which obeys a kinetic equation. The latter equation is rigorously derived from that for the correlation functions by the scaling procedure. We prove that the kinetic equation has a unique solution ϱ[subscript t], t∈[0,+∞).

Generalizations of the Szemerédi–Trotter Theorem

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Generalizations of the Szemerédi–Trotter Theorem Sharir, Micha; Solomon, Noam; Kalia, Saarik K.; Yang, Ben We generalize the Szemerédi–Trotter incidence theorem, to bound the number of complete flags in higher dimensions. Specifically, for each i=0,1,…,d−1, we are given a finite set S[subscript i] of i-flats in ℝ[superscript d] or in ℂ[superscript d], and a (complete) flag is a tuple (f[subscript 0],f[subscript 1],…,f[subscript d−1]), where f[subscript i]∈S[subscript i] for each i and f[subscript i]⊂f[subscript i+1] for each i=0,1,…,d−2. Our main result is an upper bound on the number of flags which is tight in the worst case. We also study several other kinds of incidence problems, including (i) incidences between points and lines in ℝ[superscript 3] such that among the lines incident to a point, at most O(1) of them can be coplanar, (ii) incidences with Legendrian lines in ℝ[superscript 3], a special class of lines that arise when considering flags that are defined in terms of other groups, and (iii) flags in ℝ[superscript 3] (involving points, lines, and planes), where no given line can contain too many points or lie on too many planes. The bound that we obtain in (iii) is nearly tight in the worst case. Finally, we explore a group theoretic interpretation of flags, a generalized version of which leads us to new incidence problems.

Almost sure convergence of the forward–backward–forward splitting algorithm

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Almost sure convergence of the forward–backward–forward splitting algorithm Vu, Bang Cong In this paper, we propose a stochastic forward–backward–forward splitting algorithm and prove its almost sure weak convergence in real separable Hilbert spaces. Applications to composite monotone inclusion and minimization problems are demonstrated.

Infinite random matrix theory, tridiagonal bordered Toeplitz matrices, and the moment problem

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Infinite random matrix theory, tridiagonal bordered Toeplitz matrices, and the moment problem Dubbs, Alexander Joseph; Edelman, Alan The four major asymptotic level density laws of random matrix theory may all be showcased through their Jacobi parameter representation as having a bordered Toeplitz form. We compare and contrast these laws, completing and exploring their representations in one place. Inspired by the bordered Toeplitz form, we propose an algorithm for the finite moment problem by proposing a solution whose density has a bordered Toeplitz form.

Processing and Mechanical Property Characterization of Aligned Carbon Nanotube Carbon Matrix Nanocomposites

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Processing and Mechanical Property Characterization of Aligned Carbon Nanotube Carbon Matrix Nanocomposites Stein, Itai Y; Vincent, Hanna M.; Steiner III, Stephen Alan; Colombini, Elena; Wardle, Brian L Materials comprising carbon nanotube (CNT) aligned nanowire (NW) polymer nanocomposites (A-PNCs) are emerging as next-generation materials for use in aerospace structures. Enhanced operating regimes, such as operating temperatures, motivate the study of CNT aligned NW ceramic matrix nanocomposites (A-CMNCs). Here we report the synthesis of CNT A-CMNCs through the pyrolysis of CNT A-PNC precursors, thereby creating carbon matrix CNT A-CMNCs. Characterization reveals that the fabrication of high strength, high temperature, lightweight next-generation aerospace materials is possible using this method. Additional characterization and modeling are planned.

Employing Halogen Bonding Interactions in Chemiresistive Gas Sensors

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Employing Halogen Bonding Interactions in Chemiresistive Gas Sensors Weis, Jonathan Garrett; Ravnsbaek, Jens Bomholdt; Mirica, Katherine; Swager, Timothy M This paper reports the use of halogen bonding interactions for gas-phase detection of pyridine in SWCNT-based chemiresistive sensors with sub-ppm theoretical detection limits. The chemiresistors are prepared by solvent-free ball-milling of single-walled carbon nanotubes (SWCNTs) and aryl halide-based selectors, compression into a pellet, and subsequent mechanical abrasion between gold electrodes on paper. The sensing responses reflect halogen bonding trends, with few exceptions. The predominant signal transduction mechanism is likely attributed to swelling of the insulating haloarene matrix.

Direct synthesis of Z-alkenyl halides through catalytic cross-metathesis

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Direct synthesis of Z-alkenyl halides through catalytic cross-metathesis Koh, Ming Joo; Nguyen, Thach T.; Zhang, Hanmo; Hoveyda, Amir H.; Schrock, Richard Royce Olefin metathesis has had a large impact on modern organic chemistry, but important shortcomings remain: for example, the lack of efficient processes that can be used to generate acyclic alkenyl halides. Halo-substituted ruthenium carbene complexes decompose rapidly or deliver low activity and/or minimal stereoselectivity, and our understanding of the corresponding high-oxidation-state systems is limited. Here we show that previously unknown halo-substituted molybdenum alkylidene species are exceptionally reactive and are able to participate in high-yielding olefin metathesis reactions that afford acyclic 1,2-disubstituted Z-alkenyl halides. Transformations are promoted by small amounts of a catalyst that is generated in situ and used with unpurified, commercially available and easy-to-handle liquid 1,2-dihaloethene reagents, and proceed to high conversion at ambient temperature within four hours. We obtain many alkenyl chlorides, bromides and fluorides in up to 91 per cent yield and complete Z selectivity. This method can be used to synthesize biologically active compounds readily and to perform site- and stereoselective fluorination of complex organic molecules.

Deterministic Switching of Hierarchy during Wrinkling in Quasi-Planar Bilayers 

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Deterministic Switching of Hierarchy during Wrinkling in Quasi-Planar Bilayers  Saha, Sourabh Kumar; Culpepper, Martin Emergence of hierarchy during compression of quasi-planar bilayers is preceded by a mode-locked state during which the quasi-planar form persists. Transition to hierarchy is determined entirely by geometrically observable parameters. This results in a universal transition phase diagram that enables one to deterministically tune hierarchy even with limited knowledge about material properties.

Models of human core transcriptional regulatory circuitries

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Models of human core transcriptional regulatory circuitries Saint-André, Violaine; Federation, Alexander J.; Lin, Charles Y.; Abraham, Brian J.; Lee, Tong Ihn; Bradner, James E.; Reddy, Jessica; Young, Richard A A small set of core transcription factors (TFs) dominates control of the gene expression program in embryonic stem cells and other well-studied cellular models. These core TFs collectively regulate their own gene expression, thus forming an interconnected auto-regulatory loop that can be considered the core transcriptional regulatory circuitry (CRC) for that cell type. There is limited knowledge of core TFs, and thus models of core regulatory circuitry, for most cell types. We recently discovered that genes encoding known core TFs forming CRCs are driven by super-enhancers, which provides an opportunity to systematically predict CRCs in poorly studied cell types through super-enhancer mapping. Here, we use super-enhancer maps to generate CRC models for 75 human cell and tissue types. These core circuitry models should prove valuable for further investigating cell-type–specific transcriptional regulation in healthy and diseased cells.

The seasonal variation of the upper layers of the South China Sea (SCS) circulation and the Indonesian through flow (ITF): An ocean model study

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The seasonal variation of the upper layers of the South China Sea (SCS) circulation and the Indonesian through flow (ITF): An ocean model study Xu, Danya; Rizzoli, Paola M The upper layer, wind-driven circulation of the South China Sea (SCS), its through-flow (SCSTF) and the Indonesian through flow (ITF) are simulated using a high resolution model, FVCOM (finite volume coastal ocean model) in a regional domain comprising the Maritime Continent. The regional model is embedded in the MIT global ocean general circulation model (ogcm) which provides surface forcing and boundary conditions of all the oceanographic variables at the lateral open boundaries in the Pacific and Indian oceans. A five decade long simulation is available from the MITgcm and we choose to investigate and compare the climatologies of two decades, 1960–1969 and 1990–1999. The seasonal variability of the wind-driven circulation produced by the monsoon system is realistically simulated. In the SCS the dominant driving force is the monsoon wind and the surface circulation reverses accordingly, with a net cyclonic tendency in winter and anticyclonic in summer. The SCS circulation in the 90s is weaker than in the 60s because of the weaker monsoon system in the 90s. In the upper 50 m the interaction between the SCSTF and ITF is very important. The southward ITF can be blocked by the SCSTF at the Makassar Strait during winter. In summer, part of the ITF feeds the SCSTF flowing into the SCS through the Karimata Strait. Differently from the SCS, the ITF is primarily controlled by the sea level difference between the western Pacific and eastern Indian Ocean. The ITF flow, consistently southwestward below the surface layer, is stronger in the 90s. The volume transports for winter, summer and yearly are estimated from the simulation through all the interocean straits. On the annual average, there is a ∼5.6 Sv of western Pacific water entering the SCS through the Luzon Strait and ∼1.4 Sv exiting through the Karimata Strait into the Java Sea. Also, ∼2 Sv of SCS water enters the Sulu Sea through the Mindoro Strait, while ∼2.9 Sv flow southwards through the Sibutu Strait merging into the ITF. The ITF inflow occurs through the Makassar Strait (up to ∼62%) and the Lifamatola Strait (∼38%). The annual average volume transport of the ITF inflow from the simulation is ∼15 Sv in the 60s and ∼16.6 Sv in the 90s, very close to the long term observations. The ITF outflow through the Lombok, Ombai and Timor straits is ∼16.8 Sv in the 60s and 18.9 Sv in the 90s, with the outflow greater by 1.7 Sv and 2.3 Sv respectively. The transport estimates of the simulation at all the straits are in rather good agreement with the observational estimates. We analyze the thermal structure of the domain in the 60s and 90s and assess the simulated temperature patterns against the SODA reanalysis product, with special focus on the shallow region of the SCS. The SODA dataset clearly shows that the yearly averaged temperatures of the 90s are overall warmer than those of the 60s in the surface, intermediate and some of the deep layers and the decadal differences (90s − 60s) indicate that the overall warming of the SCS interior is a local effect. In the simulation the warm trend from the 60s to the 90s in well reproduced in the surface layer. In particular, the simulated temperature profiles at two shallow sites at midway in the SCSTF agree rather well with the SODA profiles. However, the warming trend in the intermediate (deep) layers is not reproduced in the simulation. We find that this deficiency is mostly due to a deficiency in the initial temperature fields provide by the MITgcm.

Design Catalogs: A Systematic Approach to Design and Value Flexibility in Engineering Systems

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Design Catalogs: A Systematic Approach to Design and Value Flexibility in Engineering Systems Cardin, Michel-Alexandre; Geltner, David M; de Neufville, Richard L This paper proposes design catalogs as an efficient systematic process for identifying and evaluating improved designs in engineering systems by exploiting ideas of flexibility. Standard design and evaluation approaches typically do not cope well with a range of possible operating conditions. They often simplify considerations of uncertainty, which may lead to designs that do not perform as well as those responding dynamically to changing conditions. The proposed process addresses the complexity of the design problem under uncertainty, recognizing that it is impossible to analyze all possible combinations of evolutions, and the flexible ways in which the system could adapt over time. The process creates a small subset of designs that collectively perform well over a range of scenarios. It bundles representative scenarios and their flexible responses to enable a more thorough analysis that accounts explicitly for uncertainty—and enable considerations of improved designs. Each element consists of combinations of design variables, parameters, and management decision rules carefully selected, and referred as operating plans. In the example analysis, the process improves economic performance by 37% as compared to standard methods in an infrastructure system case study, while exploring only 3% of the design space. It reaches 86% of the stochastically optimal solution while being 183 times faster computationally in the example numerical study. The systematic property aims for practical applications in industry. In each phase, it gives the freedom to rely on the designer's expertise with the system, or to consider analytical tools already in use at the design organization.

Experimental testing of a semi-autonomous multi-vehicle collision avoidance algorithm at an intersection testbed

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Experimental testing of a semi-autonomous multi-vehicle collision avoidance algorithm at an intersection testbed Rizzi, Andrea; Colombo, Alessandro; Ahn, Heejin; Del Vecchio, Domitilla This paper describes the implementation of a multi-vehicle supervisor to prevent collisions at intersections. The experiments are performed on an intersection testbed consisting of three RC cars. Here, we account for uncertainty in car dynamics and state measurement, and the presence of an uncontrolled car, which is human-driven. The supervisor overrides the controlled cars only when necessary to avoid a possible future collision. From the experiments, we demonstrate that intersection collisions are averted, that is, the cars continuously and safely run on the paths without stopping 92.8% of the times.

Leveraging Possibilistic Beliefs in Unrestricted Combinatorial Auctions

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Leveraging Possibilistic Beliefs in Unrestricted Combinatorial Auctions Chen, Jing; Micali, Silvio In unrestricted combinatorial auctions, we put forward a mechanism that guarantees a meaningful revenue benchmark based on the possibilistic beliefs that the players have about each other’s valuations. In essence, the mechanism guarantees, within a factor of two, the maximum revenue that the “best informed player” would be sure to obtain if he/she were to sell the goods to his/her opponents via take-it-or-leave-it offers. Our mechanism is probabilistic and of an extensive form. It relies on a new solution concept, for analyzing extensive-form games of incomplete information, which assumes only mutual belief of rationality. Moreover, our mechanism enjoys several novel properties with respect to privacy, computation and collusion.

Targeting MTHFD2 in acute myeloid leukemia

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Targeting MTHFD2 in acute myeloid leukemia Pikman, Yana; Alexe, Gabriela; Furman, Andrew; Chen, Liying M.; Frumm, Stacey M.; Ross, Linda; Fenouille, Nina; Bassil, Christopher F.; Gould, Joshua; Stone, Richard M.; DeAngelo, Daniel J.; Galinsky, Ilene; Clish, Clary B.; Kung, Andrew L.; Banerji, Versha; Stegmaier, Kimberly; Puissant, Alexandre; Lewis, Caroline; Ramos, Azucena; Hemann, Michael; Vander Heiden, Matthew G. Drugs targeting metabolism have formed the backbone of therapy for some cancers. We sought to identify new such targets in acute myeloid leukemia (AML). The one-carbon folate pathway, specifically methylenetetrahydrofolate dehydrogenase-cyclohydrolase 2 (MTHFD2), emerged as a top candidate in our analyses. MTHFD2 is the most differentially expressed metabolic enzyme in cancer versus normal cells. Knockdown of MTHFD2 in AML cells decreased growth, induced differentiation, and impaired colony formation in primary AML blasts. In human xenograft and MLL-AF9 mouse leukemia models, MTHFD2 suppression decreased leukemia burden and prolonged survival. Based upon primary patient AML data and functional genomic screening, we determined that FLT3-ITD is a biomarker of response to MTHFD2 suppression. Mechanistically, MYC regulates the expression of MTHFD2, and MTHFD2 knockdown suppresses the TCA cycle. This study supports the therapeutic targeting of MTHFD2 in AML. It has been known for decades that cancer cells have an altered metabolism. As early as the 1920s, Otto Warburg observed that tumor cells consume glucose at a high rate and undergo fermentation even in the presence of oxygen (Warburg et al., 1927). Since then, drugs targeting metabolism have transformed the treatment of certain cancers. In the 1940s, the discovery and application of aminopterin, which was later found to target dihydrofolate reductase (DHFR), a cytoplasmic enzyme involved in one-carbon folate metabolism, yielded the first remission in a child with acute lymphoblastic leukemia (Farber et al., 1948). Other folate derivatives, such as methotrexate, were later developed. More recently, drugs such as 5-fluorouracil and pemetrexed that target thymidylate synthetase, another enzyme involved in one-carbon folate metabolism, were found to be effective therapies for some cancers (Locasale, 2013). The discovery of germline and somatic mutations that alter metabolic proteins in cancer further supports the role of altered metabolism in cancer pathogenesis. Mutations in genes of the succinate dehydrogenase complex, critical for both the tricarboxylic acid (TCA) cycle and electron transport chain, have been implicated in the pathogenesis of hereditary paragangliomas (Baysal et al., 2000; Niemann and Müller, 2000), pheochromocytomas (Astuti et al., 2001), renal cell cancer (Vanharanta et al., 2004), and gastrointestinal stromal tumors (Janeway et al., 2011; Pantaleo et al., 2011). In addition, mutations in isocitrate dehydrogenases 1 and 2 (IDH1 and IDH2) have been found in subsets of gliomas (Yan et al., 2009; Brennan et al., 2013) and acute myeloid leukemia (AML; Paschka et al., 2010; Cancer Genome Atlas Research Network, 2013), among other malignancies. Drugs targeting these mutant proteins have entered the clinic with some successes in early phase trials (Stein et al. 2014. 56th Annual American Hematoligical Society Annual Meeting and Exposition. Abstract 115.). Moreover, as understanding of the metabolic derangements necessary to promote and maintain the malignant state continues to expand, so does the list of potential drug targets. For example, aerobic glycolysis is thought to enable the generation of the nucleotides, proteins, and lipids necessary to maintain the malignant proliferative state, in part through regulation of the glycolytic enzyme pyruvate kinase (Vander Heiden et al., 2010). Additionally, the discovery of the critical importance of glycine and serine in cancer metabolism has led to a resurgence in interest in better understanding the mechanistic relevance of one-carbon folate metabolism (Jain et al., 2012; Zhang et al., 2012; Labuschagne et al., 2014; Ye et al., 2014; Kim et al., 2015; Maddocks et al., 2016). Although drugs targeting metabolism, such as methotrexate and asparaginase (a drug that reduces the availability of asparagine and glutamine), have been critical for the treatment of acute lymphoblastic leukemia, they are not used in therapy for AML, a hematopoietic malignancy where cure rates are still quite poor despite high-dose cytotoxic chemotherapy, including stem cell transplantation. This is especially true for patients with subtypes of AML characterized by high-risk features, such as the presence of FLT3-ITD mutations. New therapies are urgently needed for the treatment of these patients. In this study, we set out to define common mechanisms critical to the maintenance of AML cells to nominate novel, potentially targetable metabolic pathways for the treatment of this disease. We integrated gene expression signatures generated from the treatment of AML cells with multiple small molecules known to promote AML differentiation and death. Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2), an NAD+-dependent enzyme with dehydrogenase and cyclohydrolase activity, which plays an essential role in mitochondrial one-carbon folate metabolism, was prioritized as a target relevant to AML cell growth and differentiation. Suppression of MTHFD2 impaired AML growth and induced differentiation in vitro and impaired disease progression in multiple mouse models of AML. Additionally, FLT3-ITD mutations are a biomarker of response to MTHFD2 suppression. Mechanistically, MYC directly regulates MTHFD2 expression, and suppression of MTHFD2 leads to marked alteration of the TCA cycle.

Replication fork instability and the consequences of fork collisions from rereplication

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Replication fork instability and the consequences of fork collisions from rereplication Orr-Weaver, Terry; Alexander, Jessica Lynne Replication forks encounter obstacles that must be repaired or bypassed to complete chromosome duplication before cell division. Proteomic analysis of replication forks suggests that the checkpoint and repair machinery travels with unperturbed forks, implying that they are poised to respond to stalling and collapse. However, impaired fork progression still generates aberrations, including repeat copy number instability and chromosome rearrangements. Deregulated origin firing also causes fork instability if a newer fork collides with an older one, generating double-strand breaks (DSBs) and partially rereplicated DNA. Current evidence suggests that multiple mechanisms are used to repair rereplication damage, yet these can have deleterious consequences for genome integrity.

Bidding to drive: Car license auction policy in Shanghai and its public acceptance

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Bidding to drive: Car license auction policy in Shanghai and its public acceptance Chen, Xiaojie; Zhao, Jinhua Increased automobile ownership and use in China over the last two decades has increased energy consumption, worsened air pollution, and exacerbated congestion. However, the countrywide growth in car ownership conceals great variation among cities. For example, Shanghai and Beijing each had about 2 million motor vehicles in 2004, but by 2010, Beijing had 4.8 million motor vehicles whereas Shanghai had only 3.1 million. Among the factors contributing to this divergence is Shanghai’s vehicle control policy, which uses monthly license auctions to limit the number of new cars. The policy appears to be effective: in addition to dampening growth in car ownership, it generates annual revenues up to 5 billion CNY (800 million USD). But, despite these apparent successes, the degree to which the public accepts this policy is unknown. This study surveys 524 employees at nine Shanghai companies to investigate the policy acceptance of Shanghai’s license auction by the working population, and the factors that contribute to that acceptance: Perceived policy effectiveness, affordability, equity concerns, and implementation. Respondents perceive the policy to be effective, but are moderately negative towards the policy nonetheless. However, they expect that others accept the policy more than they do. Respondents also hold consistently negative perceptions about the affordability of the license, the effects on equity, and the implementation process. Revenue usage is not seen as transparent, which is exacerbated by a perception that government vehicles enjoy advantages in obtaining a license, issues with the bidding process and technology, and difficulties in obtaining information about the auction policy. Nevertheless, respondents believe that license auctions and congestion charges are more effective and acceptable than parking charges and fuel taxes. To improve public acceptability of the policy, we make five recommendations: Transparency in revenue usage; transparency in government vehicle licensing and use, categorizing licenses by vehicle type, implementation and technology improvements to increase bidding convenience, and policies that restrict vehicle usage in congested locations.
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