A randomized controlled design reveals barriers to citizenship for low-income immigrants.

abstract：:Studies of replicative and chronological lifespan in Saccharomyces cerevisiae have advanced understanding of longevity in all eukaryotes. Chronological lifespan in this species is defined as the age-dependent viability of nondividing cells. To date this parameter has only been estimated under calorie restriction, mimi...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Nagarajan S,Kruckeberg AL,Schmidt KH,Kroll E,Hamilton M,McInnerney K,Summers R,Taylor T,Rosenzweig F

更新日期：2014-04-15 00:00:00

abstract：:Whether the regulatory protein of an inducible operon for a catabolic pathway is a positive or a negative element in the control of expression is correlated with the frequent or infrequent presence, respectively, of the system's substrate in the natural environment. ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Savageau MA

更新日期：1974-06-01 00:00:00

abstract：:The epothilones represent a promising class of natural product-based antitumor drug candidates. Although these compounds operate through a microtubule stabilization mechanism similar to that of taxol, the epothilones offer a major potential therapeutic advantage in that they retain their activity against multidrug-res...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Chou TC,Zhang X,Zhong ZY,Li Y,Feng L,Eng S,Myles DR,Johnson R Jr,Wu N,Yin YI,Wilson RM,Danishefsky SJ

更新日期：2008-09-02 00:00:00

abstract：:Genes that are up- and down-regulated by thyroid hormone in the tail resorption program of Xenopus laevis have been isolated by a gene expression screen, sequenced, and identified in the GenBank data base. The entire program is estimated to consist of fewer than 35 up-regulated and fewer than 10 down-regulated genes; ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Brown DD,Wang Z,Furlow JD,Kanamori A,Schwartzman RA,Remo BF,Pinder A

更新日期：1996-03-05 00:00:00

abstract：:Fish in schooling formations navigate complex flow fields replete with mechanical energy in the vortex wakes of their companions. Their schooling behavior has been associated with evolutionary advantages including energy savings, yet the underlying physical mechanisms remain unknown. We show that fish can improve thei...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Verma S,Novati G,Koumoutsakos P

更新日期：2018-06-05 00:00:00

abstract：:Quiescent BALB/c 3T3 cells exposed briefly to a platelet-derived growth factor (PDGF) become "competent" to replicate their DNA but do not "progress" into S phase unless incubated with growth factors contained in platelet-poor plasma. Plasma from hypophysectomized rats is deficient in progression activity; it does not...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Stiles CD,Capone GT,Scher CD,Antoniades HN,Van Wyk JJ,Pledger WJ

更新日期：1979-03-01 00:00:00

abstract：:Refinement of neural circuits in the mammalian cerebral cortex shapes brain function during development and in the adult. However, the signaling mechanisms underlying the synapse-specific shrinkage and loss of spiny synapses when neural circuits are remodeled remain poorly defined. Here, we show that low-frequency glu...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Oh WC,Hill TC,Zito K

更新日期：2013-01-22 00:00:00

abstract：:Bone mineralization is an essential step during the embryonic development of vertebrates, and bone serves vital functions in human physiology. To systematically identify unique gene functions essential for osteogenesis, we performed a forward genetic screen in zebrafish and isolated a mutant, no bone (nob), that does ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Huitema LF,Apschner A,Logister I,Spoorendonk KM,Bussmann J,Hammond CL,Schulte-Merker S

更新日期：2012-12-26 00:00:00

abstract：:The mechanism by which antifreeze proteins (AFPs) irreversibly bind to ice has not yet been resolved. The ice-binding site of an AFP is relatively hydrophobic, but also contains many potential hydrogen bond donors/acceptors. The extent to which hydrogen bonding and the hydrophobic effect contribute to ice binding has ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Garnham CP,Campbell RL,Davies PL

更新日期：2011-05-03 00:00:00

abstract：:A simple model for necking and detachment of subducting slabs is developed to include the coupling between grain-sensitive rheology and grain-size evolution with damage. Necking is triggered by thickened buoyant crust entrained into a subduction zone, in which case grain damage accelerates necking and allows for relat...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bercovici D,Schubert G,Ricard Y

更新日期：2015-02-03 00:00:00

abstract：:A model for the chain melting phase transition in dilute aqueous phospholipid bilayer dispersions is presented. This model includes interactions between head groups, between hydrocarbon chains, and within the chains. The head groups are modeled as hard disks which are constrained to lie on a two-dimensional surface se...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Jacobs RE,Hudson B,Andersen HC

更新日期：1975-10-01 00:00:00

abstract：:Random graphs are useful models of social and technological networks. To date, most of the research in this area has concerned geometric properties of the graphs. Here we focus on processes taking place on the network. In particular we are interested in how their behavior on networks differs from that in homogeneously...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Durrett R

更新日期：2010-03-09 00:00:00

abstract：:Mutational inactivation of the retinoblastoma (RB) gene has been implicated in the genesis of retinoblastoma, osteosarcoma, and other human tumors. Our strategy has been to characterize naturally occurring mutants from tumor cells to pinpoint potential domains of RB protein crucial for tumor suppression. We show here ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Shew JY,Lin BT,Chen PL,Tseng BY,Yang-Feng TL,Lee WH

更新日期：1990-01-01 00:00:00

abstract：:Explaining the maintenance of tropical forest diversity under the countervailing forces of drift and competition poses a major challenge to ecological theory. Janzen-Connell effects, in which host-specific natural enemies restrict the recruitment of juveniles near conspecific adults, provide a potential mechanism. Jan...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Levi T,Barfield M,Barrantes S,Sullivan C,Holt RD,Terborgh J

更新日期：2019-01-08 00:00:00

abstract：:In the plant Nicotiana plumbaginifolia, manganese superoxide dismutase (MnSOD) is synthesized in the cytoplasm as a preprotein and is subsequently translocated to the mitochondrial matrix with corresponding cleavage of an NH2-terminal leader sequence. To determine whether the plant enzyme could replace the endogenous ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bowler C,Alliotte T,Van den Bulcke M,Bauw G,Vandekerckhove J,Van Montagu M,Inzé D

更新日期：1989-05-01 00:00:00

abstract：:Mucosal surfaces are a main entry point for pathogens and the principal sites of defense against infection. Both bacteria and phage are associated with this mucus. Here we show that phage-to-bacteria ratios were increased, relative to the adjacent environment, on all mucosal surfaces sampled, ranging from cnidarians t...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Barr JJ,Auro R,Furlan M,Whiteson KL,Erb ML,Pogliano J,Stotland A,Wolkowicz R,Cutting AS,Doran KS,Salamon P,Youle M,Rohwer F

更新日期：2013-06-25 00:00:00

abstract：:Escherichia coli K12 2320(lambda)-15B has a mutation that results in ochre suppressor activity.(1) This mutation concomitantly causes a decreased growth rate in rich medium, an increased sensitivity to streptomycin,(1) and the production of some altered 30S ribosomes which are differentially sensitive to RNase.(2) The...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Gartner TK,Orias E,Lannan JE,Beeson J,Reid PJ

更新日期：1969-03-01 00:00:00

abstract：:Sensitive optical signal detection can often be confounded by the presence of a significant background, and, as such, predetection background suppression is substantively important for weak signal detection. In this paper, we present a novel optical structure design, termed surface-wave-enabled darkfield aperture (SWE...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Zheng G,Cui X,Yang C

更新日期：2010-05-18 00:00:00

abstract：:In animals and in man, diverse immunologic functions are mediated by specialized T-cell (thymus-derived lymphocyte) subsets that are distinguishable from one another on the basis of differences in cell surface determinants. Unfortunately, in humans, subset-specific antibodies have been difficult to generate. In this s...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Engleman EG,Benike C,Osborne B,Goldsby R

更新日期：1980-03-01 00:00:00

abstract：:Daphnia pulex de Geer and Daphnia magna Straus populations cannot be maintained in defined (sensu stricto) media containing less than 0.1 part per billion (ppb) of selenium. A concentration of 1 ppb is sufficient to satisfy minimal needs in otherwise sufficient media. In the first generation with no selenium added to ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Keating KI,Dagbusan BC

更新日期：1984-06-01 00:00:00

abstract：:Genetic studies of the white locus have shown that it has a distal region where structural mutations occur and a proximal region where regulatory mutations occur. To better understand the molecular basis of this genetic organization we have analyzed white locus transcription. A 2.7-kilobase transcript comprising 0.000...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： O'hare K,Levis R,Rubin GM

更新日期：1983-11-01 00:00:00

abstract：:The formation of viable genetic chimeras in mammals through the transfer of cells between siblings in utero is rare. Using microsatellite DNA markers, we show here that chimerism in marmoset (Callithrix kuhlii) twins is not limited to blood-derived hematopoietic tissues as was previously described. All somatic tissue ...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Ross CN,French JA,Ortí G

更新日期：2007-04-10 00:00:00

abstract：:Language and analytic processing are currently thought to be represented in the left hemisphere, whereas spatial and holistic processing would involve primarily the right hemisphere in man. An experimental paradigm for engaging the nonlanguage hemisphere (generally the right) is described. This involves active touch e...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Desmedt JE

更新日期：1977-09-01 00:00:00

abstract：:p53, the most commonly mutated gene in human tumors, is believed to play a crucial role in the prevention of cancer by protecting cells from mutation, a theory commonly known as the "Guardian of the Genome" hypothesis. There are two hypotheses as to how this can occur. In the first, p53 protects the genome by retardin...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Bielas JH,Heddle JA

更新日期：2003-10-28 00:00:00

abstract：:The endometrial epithelium of the uterus regenerates periodically. The cellular source of newly regenerated endometrial epithelia during a mouse estrous cycle or a human menstrual cycle is presently unknown. Here, I have used single-cell lineage tracing in the whole mouse uterus to demonstrate that epithelial stem cel...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Jin S

更新日期：2019-04-02 00:00:00

abstract：:2(S)-dihydroxypropanesulfonate (DHPS) is a microbial degradation product of 6-deoxy-6-sulfo-d-glucopyranose (sulfoquinovose), a component of plant sulfolipid with an estimated annual production of 1010 tons. DHPS is also at millimolar levels in highly abundant marine phytoplankton. Its degradation and sulfur recycling...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Liu J,Wei Y,Lin L,Teng L,Yin J,Lu Q,Chen J,Zheng Y,Li Y,Xu R,Zhai W,Liu Y,Liu Y,Cao P,Ang EL,Zhao H,Yuchi Z,Zhang Y

更新日期：2020-07-07 00:00:00

abstract：:31P nuclear magnetic relaxation rates for phosphocreatine in intact frog gastrocnemius were compared with those observed in model solutions at 4 degrees, a temperature at which muscle maintains its physiological state for at least 5 hr. Both nuclear Overhauser effect and spin-lattice relaxation rate (1/T1) experiments...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Cohen SM,Burt CT

更新日期：1977-10-01 00:00:00

abstract：:Fetal exposure to environmental insults increases the susceptibility to late-onset neuropsychiatric disorders. Alcohol is listed as one of such prenatal environmental risk factors and known to exert devastating teratogenetic effects on the developing brain, leading to complex neurological and psychiatric symptoms obse...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Hashimoto-Torii K,Kawasawa YI,Kuhn A,Rakic P

更新日期：2011-03-08 00:00:00

abstract：:The callipyge mutation (CLPG) is an A to G transition that affects a muscle-specific long-range control element located in the middle of the 90-kb DLK1-GTL2 intergenic (IG) region. It causes ectopic expression of a 327-kb cluster of imprinted genes in skeletal muscle, resulting in the callipyge muscular hypertrophy an...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Takeda H,Caiment F,Smit M,Hiard S,Tordoir X,Cockett N,Georges M,Charlier C

更新日期：2006-05-23 00:00:00

abstract：:Are judicial rulings based solely on laws and facts? Legal formalism holds that judges apply legal reasons to the facts of a case in a rational, mechanical, and deliberative manner. In contrast, legal realists argue that the rational application of legal reasons does not sufficiently explain the decisions of judges an...

journal_title：Proceedings of the National Academy of Sciences of the United States of America

authors： Danziger S,Levav J,Avnaim-Pesso L

更新日期：2011-04-26 00:00:00