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Showing papers by "University of Florida published in 2006"


Journal ArticleDOI
15 Nov 2006-Proteins
TL;DR: An effort to improve the φ/ψ dihedral terms in the ff99 energy function achieves a better balance of secondary structure elements as judged by improved distribution of backbone dihedrals for glycine and alanine with respect to PDB survey data.
Abstract: The ff94 force field that is commonly associated with the Amber simulation package is one of the most widely used parameter sets for biomolecular simulation. After a decade of extensive use and testing, limitations in this force field, such as over-stabilization of alpha-helices, were reported by us and other researchers. This led to a number of attempts to improve these parameters, resulting in a variety of "Amber" force fields and significant difficulty in determining which should be used for a particular application. We show that several of these continue to suffer from inadequate balance between different secondary structure elements. In addition, the approach used in most of these studies neglected to account for the existence in Amber of two sets of backbone phi/psi dihedral terms. This led to parameter sets that provide unreasonable conformational preferences for glycine. We report here an effort to improve the phi/psi dihedral terms in the ff99 energy function. Dihedral term parameters are based on fitting the energies of multiple conformations of glycine and alanine tetrapeptides from high level ab initio quantum mechanical calculations. The new parameters for backbone dihedrals replace those in the existing ff99 force field. This parameter set, which we denote ff99SB, achieves a better balance of secondary structure elements as judged by improved distribution of backbone dihedrals for glycine and alanine with respect to PDB survey data. It also accomplishes improved agreement with published experimental data for conformational preferences of short alanine peptides and better accord with experimental NMR relaxation data of test protein systems.

6,146 citations


Journal ArticleDOI
Gerald A. Tuskan1, Gerald A. Tuskan2, Stephen P. DiFazio2, Stephen P. DiFazio3, Stefan Jansson4, Joerg Bohlmann5, Igor V. Grigoriev6, Uffe Hellsten6, Nicholas H. Putnam6, Steven G. Ralph5, Stephane Rombauts7, Asaf Salamov6, Jacquie Schein, Lieven Sterck7, Andrea Aerts6, Rishikeshi Bhalerao4, Rishikesh P. Bhalerao8, Damien Blaudez9, Wout Boerjan7, Annick Brun9, Amy M. Brunner10, Victor Busov11, Malcolm M. Campbell12, John E. Carlson13, Michel Chalot9, Jarrod Chapman6, G.-L. Chen2, Dawn Cooper5, Pedro M. Coutinho14, Jérémy Couturier9, Sarah F. Covert15, Quentin C. B. Cronk5, R. Cunningham2, John M. Davis16, Sven Degroeve7, Annabelle Déjardin9, Claude W. dePamphilis13, John C. Detter6, Bill Dirks17, Inna Dubchak6, Inna Dubchak18, Sébastien Duplessis9, Jürgen Ehlting5, Brian E. Ellis5, Karla C Gendler19, David Goodstein6, Michael Gribskov20, Jane Grimwood21, Andrew Groover22, Lee E. Gunter2, Björn Hamberger5, Berthold Heinze, Yrjö Helariutta23, Yrjö Helariutta8, Yrjö Helariutta24, Bernard Henrissat14, D. Holligan15, Robert A. Holt, Wenyu Huang6, N. Islam-Faridi22, Steven J.M. Jones, M. Jones-Rhoades25, Richard A. Jorgensen19, Chandrashekhar P. Joshi11, Jaakko Kangasjärvi23, Jan Karlsson4, Colin T. Kelleher5, Robert Kirkpatrick, Matias Kirst16, Annegret Kohler9, Udaya C. Kalluri2, Frank W. Larimer2, Jim Leebens-Mack15, Jean-Charles Leplé9, Philip F. LoCascio2, Y. Lou6, Susan Lucas6, Francis Martin9, Barbara Montanini9, Carolyn A. Napoli19, David R. Nelson26, C D Nelson22, Kaisa Nieminen23, Ove Nilsson8, V. Pereda9, Gary F. Peter16, Ryan N. Philippe5, Gilles Pilate9, Alexander Poliakov18, J. Razumovskaya2, Paul G. Richardson6, Cécile Rinaldi9, Kermit Ritland5, Pierre Rouzé7, D. Ryaboy18, Jeremy Schmutz21, J. Schrader27, Bo Segerman4, H. Shin, Asim Siddiqui, Fredrik Sterky, Astrid Terry6, Chung-Jui Tsai11, Edward C. Uberbacher2, Per Unneberg, Jorma Vahala23, Kerr Wall13, Susan R. Wessler15, Guojun Yang15, T. Yin2, Carl J. Douglas5, Marco A. Marra, Göran Sandberg8, Y. Van de Peer7, Daniel S. Rokhsar17, Daniel S. Rokhsar6 
15 Sep 2006-Science
TL;DR: The draft genome of the black cottonwood tree, Populus trichocarpa, has been reported in this paper, with more than 45,000 putative protein-coding genes identified.
Abstract: We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

4,025 citations


Journal ArticleDOI
TL;DR: In this paper, the authors present new weak lensing observations of 1E0657-558 (z = 0.296), a unique cluster merger, that enable a direct detection of dark matter, independent of assumptions regarding the nature of the gravitational force law.
Abstract: We present new weak lensing observations of 1E0657-558 (z = 0.296), a unique cluster merger, that enable a direct detection of dark matter, independent of assumptions regarding the nature of the gravitational force law. Due to the collision of two clusters, the dissipationless stellar component and the fluid-like X-ray emitting plasma are spatially segregated. By using both wide-field ground based images and HST/ACS images of the cluster cores, we create gravitational lensing maps which show that the gravitational potential does not trace the plasma distribution, the dominant baryonic mass component, but rather approximately traces the distribution of galaxies. An 8{sigma} significance spatial offset of the center of the total mass from the center of the baryonic mass peaks cannot be explained with an alteration of the gravitational force law, and thus proves that the majority of the matter in the system is unseen.

2,332 citations



Journal ArticleDOI
TL;DR: Among healthy postmenopausal women, calcium with vitamin D supplementation resulted in a small but significant improvement in hip bone density, did not significantly reduce hip fracture, and increased the risk of kidney stones.
Abstract: Background The efficacy of calcium with vitamin D supplementation for preventing hip and other fractures in healthy postmenopausal women remains equivocal. Methods We recruited 36,282 postmenopausal women, 50 to 79 years of age, who were already enrolled in a Women's Health Initiative (WHI) clinical trial. We randomly assigned participants to receive 1000 mg of elemental calcium as calcium carbonate with 400 IU of vitamin D3 daily or placebo. Fractures were ascertained for an average follow-up period of 7.0 years. Bone density was measured at three WHI centers. Results Hip bone density was 1.06 percent higher in the calcium plus vitamin D group than in the placebo group (P<0.01). Intention-to-treat analysis indicated that participants receiving calcium plus vitamin D supplementation had a hazard ratio of 0.88 for hip fracture (95 percent confidence interval, 0.72 to 1.08), 0.90 for clinical spine fracture (0.74 to 1.10), and 0.96 for total fractures (0.91 to 1.02). The risk of renal calculi increased with...

1,765 citations


Journal ArticleDOI
01 Nov 2006-JAMA
TL;DR: The Extremity Constraint Induced Therapy Evaluation (EXCITE) trial as mentioned in this paper showed that a 2-week program of constraint-induced movement therapy (CIMT) for patients more than 1 year after stroke who maintain some hand and wrist movement can improve upper extremity function that persists for at least 1 year.
Abstract: ContextSingle-site studies suggest that a 2-week program of constraint-induced movement therapy (CIMT) for patients more than 1 year after stroke who maintain some hand and wrist movement can improve upper extremity function that persists for at least 1 year.ObjectiveTo compare the effects of a 2-week multisite program of CIMT vs usual and customary care on improvement in upper extremity function among patients who had a first stroke within the previous 3 to 9 months.Design and SettingThe Extremity Constraint Induced Therapy Evaluation (EXCITE) trial, a prospective, single-blind, randomized, multisite clinical trial conducted at 7 US academic institutions between January 2001 and January 2003.ParticipantsTwo hundred twenty-two individuals with predominantly ischemic stroke.InterventionsParticipants were assigned to receive either CIMT (n = 106; wearing a restraining mitt on the less-affected hand while engaging in repetitive task practice and behavioral shaping with the hemiplegic hand) or usual and customary care (n = 116; ranging from no treatment after concluding formal rehabilitation to pharmacologic or physiotherapeutic interventions); patients were stratified by sex, prestroke dominant side, side of stroke, and level of paretic arm function.Main Outcome MeasuresThe Wolf Motor Function Test (WMFT), a measure of laboratory time and strength-based ability and quality of movement (functional ability), and the Motor Activity Log (MAL), a measure of how well and how often 30 common daily activities are performed.ResultsFrom baseline to 12 months, the CIMT group showed greater improvements than the control group in both the WMFT Performance Time (decrease in mean time from 19.3 seconds to 9.3 seconds [52% reduction] vs from 24.0 seconds to 17.7 seconds [26% reduction]; between-group difference, 34% [95% confidence interval {CI}, 12%-51%]; P<.001) and in the MAL Amount of Use (on a 0-5 scale, increase from 1.21 to 2.13 vs from 1.15 to 1.65; between-group difference, 0.43 [95% CI, 0.05-0.80]; P<.001) and MAL Quality of Movement (on a 0-5 scale, increase from 1.26 to 2.23 vs 1.18 to 1.66; between-group difference, 0.48 [95% CI, 0.13-0.84]; P<.001). The CIMT group achieved a decrease of 19.5 in self-perceived hand function difficulty (Stroke Impact Scale hand domain) vs a decrease of 10.1 for the control group (between-group difference, 9.42 [95% CI, 0.27-18.57]; P=.05).ConclusionAmong patients who had a stroke within the previous 3 to 9 months, CIMT produced statistically significant and clinically relevant improvements in arm motor function that persisted for at least 1 year.Trial Registrationclinicaltrials.gov Identifier: NCT00057018

1,662 citations


Journal ArticleDOI
TL;DR: This article found that transformational leadership is associated with the way followers view their jobs, in terms of Hackman and Oldham's (1976) core job characteristics, such as intrinsic motivation, and goal commitment.
Abstract: Although the effects of transformational leadership on task performance and organizational citizenship behavior (OCB) are well-documented, the mechanisms that explain those effects remain unclear. We propose that transformational leadership is associated with the way followers view their jobs, in terms of Hackman and Oldham’s (1976) core job characteristics. Results of our study support a structural model whereby indirect effects supplement the direct effects of transformational leadership on task performance and OCB through the mechanisms of job characteristics, intrinsic motivation, and goal commitment. Additional analyses revealed that transformational leadership relationships were significantly stronger for followers who perceived highquality leader-member exchange.

1,517 citations


Journal ArticleDOI
TL;DR: It is shown that native plant species growing on contaminated sites may have the potential for phytoremediation.

1,456 citations


Journal ArticleDOI
20 Dec 2006-JAMA
TL;DR: Cognitive training resulted in improved cognitive abilities specific to the abilities trained that continued 5 years after the initiation of the intervention, and booster training for the speed of processing group showed a significant effect on the performance-based functional measure of everyday speed ofprocessing.
Abstract: ContextCognitive training has been shown to improve cognitive abilities in older adults but the effects of cognitive training on everyday function have not been demonstrated.ObjectiveTo determine the effects of cognitive training on daily function and durability of training on cognitive abilities.Design, Setting, and ParticipantsFive-year follow-up of a randomized controlled single-blind trial with 4 treatment groups. A volunteer sample of 2832 persons (mean age, 73.6 years; 26% black), living independently in 6 US cities, was recruited from senior housing, community centers, and hospitals and clinics. The study was conducted between April 1998 and December 2004. Five-year follow-up was completed in 67% of the sample.InterventionsTen-session training for memory (verbal episodic memory), reasoning (inductive reasoning), or speed of processing (visual search and identification); 4-session booster training at 11 and 35 months after training in a random sample of those who completed training.Main Outcome MeasuresSelf-reported and performance-based measures of daily function and cognitive abilities.ResultsThe reasoning group reported significantly less difficulty in the instrumental activities of daily living (IADL) than the control group (effect size, 0.29; 99% confidence interval [CI], 0.03-0.55). Neither speed of processing training (effect size, 0.26; 99% CI, −0.002 to 0.51) nor memory training (effect size, 0.20; 99% CI, −0.06 to 0.46) had a significant effect on IADL. The booster training for the speed of processing group, but not for the other 2 groups, showed a significant effect on the performance-based functional measure of everyday speed of processing (effect size, 0.30; 99% CI, 0.08-0.52). No booster effects were seen for any of the groups for everyday problem-solving or self-reported difficulty in IADL. Each intervention maintained effects on its specific targeted cognitive ability through 5 years (memory: effect size, 0.23 [99% CI, 0.11-0.35]; reasoning: effect size, 0.26 [99% CI, 0.17-0.35]; speed of processing: effect size, 0.76 [99% CI, 0.62-0.90]). Booster training produced additional improvement with the reasoning intervention for reasoning performance (effect size, 0.28; 99% CI, 0.12-0.43) and the speed of processing intervention for speed of processing performance (effect size, 0.85; 99% CI, 0.61-1.09).ConclusionsReasoning training resulted in less functional decline in self-reported IADL. Compared with the control group, cognitive training resulted in improved cognitive abilities specific to the abilities trained that continued 5 years after the initiation of the intervention.Trial Registrationclinicaltrials.gov Identifier: NCT00298558

1,356 citations


Journal ArticleDOI

1,335 citations


Journal ArticleDOI
TL;DR: In this paper, different electrochemical systems showing the CPE dependence in the high-frequency range for the overall impedance were considered, and local electrochemical impedance spectroscopy was found to provide a good means for assessing the influence of local variations on the constant phase element (CPE) behavior seen in global impedance measurements.

Journal ArticleDOI
TL;DR: A group of aptamers have been generated for the specific recognition of leukemia cells that can specifically recognize target leukemia cells mixed with normal human bone marrow aspirates and can also identify cancer cells closely related to the target cell line in real clinical specimens.
Abstract: Using cell-based aptamer selection, we have developed a strategy to use the differences at the molecular level between any two types of cells for the identification of molecular signatures on the surface of targeted cells. A group of aptamers have been generated for the specific recognition of leukemia cells. The selected aptamers can bind to target cells with an equilibrium dissociation constant (Kd) in the nanomolar-to-picomolar range. The cell-based selection process is simple, fast, straightforward, and reproducible, and, most importantly, can be done without prior knowledge of target molecules. The selected aptamers can specifically recognize target leukemia cells mixed with normal human bone marrow aspirates and can also identify cancer cells closely related to the target cell line in real clinical specimens. The cell-based aptamer selection holds a great promise in developing specific molecular probes for cancer diagnosis and cancer biomarker discovery.

Journal ArticleDOI
TL;DR: A more general, partial-adjustment model of firm leverage indicates that firms do have target capital structures as mentioned in this paper, and the typical firm closes about one-third of the gap between its actual and its target debt ratios each year.

Journal ArticleDOI
TL;DR: A suite of mechanisms through which diversity could increase or decrease disease risk is described, and the potential applicability of these mechanisms for both vector-borne and non-vector-borne diseases, and for both specialist and generalist pathogens is illustrated.
Abstract: The transmission of infectious diseases is an inherently ecological process involving interactions among at least two, and often many, species. Not surprisingly, then, the species diversity of ecological communities can potentially affect the prevalence of infectious diseases. Although a number of studies have now identified effects of diversity on disease prevalence, the mechanisms underlying these effects remain unclear in many cases. Starting with simple epidemiological models, we describe a suite of mechanisms through which diversity could increase or decrease disease risk, and illustrate the potential applicability of these mechanisms for both vector-borne and non-vector-borne diseases, and for both specialist and generalist pathogens. We review examples of how these mechanisms may operate in specific disease systems. Because the effects of diversity on multi-host disease systems have been the subject of much recent research and controversy, we describe several recent efforts to delineate under what general conditions host diversity should increase or decrease disease prevalence, and illustrate these with examples. Both models and literature reviews suggest that high host diversity is more likely to decrease than increase disease risk. Reduced disease risk with increasing host diversity is especially likely when pathogen transmission is frequency-dependent, and when pathogen transmission is greater within species than between species, particularly when the most competent hosts are also relatively abundant and widespread. We conclude by identifying focal areas for future research, including (1) describing patterns of change in disease risk with changing diversity; (2) identifying the mechanisms responsible for observed changes in risk; (3) clarifying additional mechanisms in a wider range of epidemiological models; and (4) experimentally manipulating disease systems to assess the impact of proposed mechanisms.

Journal ArticleDOI
TL;DR: The findings indicated that attitudes correlated with a future behavior more strongly when they were easy to recall and stable over time and when participants had direct experience with the attitude object and reported their attitudes frequently.
Abstract: A meta-analysis (k of conditions = 128; N = 4,598) examined the influence of factors present at the time an attitude is formed on the degree to which this attitude guides future behavior. The findings indicated that attitudes correlated with a future behavior more strongly when they were easy to recall (accessible) and stable over time. Because of increased accessibility, attitudes more strongly predicted future behavior when participants had direct experience with the attitude object and reported their attitudes frequently. Because of the resulting attitude stability, the attitude-behavior association was strongest when attitudes were confident, when participants formed their attitude on the basis of behavior-relevant information, and when they received or were induced to think about one- rather than two-sided information about the attitude object.

Journal ArticleDOI
TL;DR: Data from this study support a model in which Sun proteins tether nesprins in the ONM via interactions spanning the PNS, and form a complex that links the nucleoskeleton and cytoskeleton (the LINC complex).
Abstract: The nuclear envelope defines the barrier between the nucleus and cytoplasm and features inner and outer membranes separated by a perinuclear space (PNS). The inner nuclear membrane contains specific integral proteins that include Sun1 and Sun2. Although the outer nuclear membrane (ONM) is continuous with the endoplasmic reticulum, it is nevertheless enriched in several integral membrane proteins, including nesprin 2 Giant (nesp2G), an 800-kD protein featuring an NH2-terminal actin-binding domain. A recent study (Padmakumar, V.C., T. Libotte, W. Lu, H. Zaim, S. Abraham, A.A. Noegel, J. Gotzmann, R. Foisner, and I. Karakesisoglou. 2005. J. Cell Sci. 118:3419–3430) has shown that localization of nesp2G to the ONM is dependent upon an interaction with Sun1. In this study, we confirm and extend these results by demonstrating that both Sun1 and Sun2 contribute to nesp2G localization. Codepletion of both of these proteins in HeLa cells leads to the loss of ONM-associated nesp2G, as does overexpression of the Sun1 lumenal domain. Both treatments result in the expansion of the PNS. These data, together with those of Padmakumar et al. (2005), support a model in which Sun proteins tether nesprins in the ONM via interactions spanning the PNS. In this way, Sun proteins and nesprins form a complex that links the nucleoskeleton and cytoskeleton (the LINC complex).

Journal ArticleDOI
TL;DR: In this article, the authors classify the effects of ecosystem service trade-offs along three axes: spatial scale, temporal scale, and reversibility, where spatial scale refers to whether the effect of the trade-off is felt locally or at a distant location, while temporal scale describes whether the effects take place relatively rapidly or slowly.
Abstract: Ecosystem service (ES) trade-offs arise from management choices made by humans, which can change the type, magnitude, and relative mix of services provided by ecosystems. Trade-offs occur when the provision of one ES is reduced as a consequence of increased use of another ES. In some cases, a trade-off may be an explicit choice; but in others, trade-offs arise without premeditation or even awareness that they are taking place. Trade-offs in ES can be classified along three axes: spatial scale, temporal scale, and reversibility. Spatial scale refers to whether the effects of the trade-off are felt locally or at a distant location. Temporal scale refers to whether the effects take place relatively rapidly or slowly. Reversibility expresses the likelihood that the perturbed ES may return to its original state if the perturbation ceases. Across all four Millennium Ecosystem Assessment scenarios and selected case study examples, trade-off decisions show a preference for provisioning, regulating, or cultural services (in that order). Supporting services are more likely to be “taken for granted.” Cultural ES are almost entirely unquantified in scenario modeling; therefore, the calculated model results do not fully capture losses of these services that occur in the scenarios. The quantitative scenario models primarily capture the services that are perceived by society as more important—provisioning and regulating ecosystem services—and thus do not fully capture tradeoffs of cultural and supporting services. Successful management policies will be those that incorporate lessons learned from prior decisions into future management actions. Managers should complement their actions with monitoring programs that, in addition to monitoring the short-term provisions of services, also monitor the long-term evolution of slowly changing variables. Policies can then be developed to take into account ES trade-offs at multiple spatial and temporal scales. Successful strategies will recognize the inherent complexities of ecosystem management and will work to develop policies that minimize the effects of ES trade-offs.

Journal ArticleDOI
TL;DR: In this article, a sampling strategy that is a combination of latin-hypercube and one-factor-at-a-time sampling that allows a global sensitivity analysis for a long list of parameters with only a limited number of model runs is described.

Journal ArticleDOI
TL;DR: The first evidence that uric acid may be a cause of metabolic syndrome is provided, possibly due to its ability to inhibit endothelial function, as well as a reduced vasodilatory response of aortic artery rings to acetylcholine.
Abstract: The worldwide epidemic of metabolic syndrome correlates with an elevation in serum uric acid as well as a marked increase in total fructose intake (in the form of table sugar and high-fructose corn syrup). Fructose raises uric acid, and the latter inhibits nitric oxide bioavailability. Because insulin requires nitric oxide to stimulate glucose uptake, we hypothesized that fructose-induced hyperuricemia may have a pathogenic role in metabolic syndrome. Four sets of experiments were performed. First, pair-feeding studies showed that fructose, and not dextrose, induced features (hyperinsulinemia, hypertriglyceridemia, and hyperuricemia) of metabolic syndrome. Second, in rats receiving a high-fructose diet, the lowering of uric acid with either allopurinol (a xanthine oxidase inhibitor) or benzbromarone (a uricosuric agent) was able to prevent or reverse features of metabolic syndrome. In particular, the administration of allopurinol prophylactically prevented fructose-induced hyperinsulinemia (272.3 vs.160.8 pmol/l, P < 0.05), systolic hypertension (142 vs. 133 mmHg, P < 0.05), hypertriglyceridemia (233.7 vs. 65.4 mg/dl, P < 0.01), and weight gain (455 vs. 425 g, P < 0.05) at 8 wk. Neither allopurinol nor benzbromarone affected dietary intake of control diet in rats. Finally, uric acid dose dependently inhibited endothelial function as manifested by a reduced vasodilatory response of aortic artery rings to acetylcholine. These data provide the first evidence that uric acid may be a cause of metabolic syndrome, possibly due to its ability to inhibit endothelial function. Fructose may have a major role in the epidemic of metabolic syndrome and obesity due to its ability to raise uric acid.

Journal ArticleDOI
08 Feb 2006-JAMA
TL;DR: A dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women and achieved only modest effects on CVD risk factors, suggesting that more focused diet and lifestyle interventions may be needed to improve risk factors and reduce CVDrisk.
Abstract: ContextMultiple epidemiologic studies and some trials have linked diet with cardiovascular disease (CVD) prevention, but long-term intervention data are needed.ObjectiveTo test the hypothesis that a dietary intervention, intended to be low in fat and high in vegetables, fruits, and grains to reduce cancer, would reduce CVD risk.Design, Setting, and ParticipantsRandomized controlled trial of 48 835 postmenopausal women aged 50 to 79 years, of diverse backgrounds and ethnicities, who participated in the Women's Health Initiative Dietary Modification Trial. Women were randomly assigned to an intervention (19 541 [40%]) or comparison group (29 294 [60%]) in a free-living setting. Study enrollment occurred between 1993 and 1998 in 40 US clinical centers; mean follow-up in this analysis was 8.1 years.InterventionIntensive behavior modification in group and individual sessions designed to reduce total fat intake to 20% of calories and increase intakes of vegetables/fruits to 5 servings/d and grains to at least 6 servings/d. The comparison group received diet-related education materials.Main Outcome MeasuresFatal and nonfatal coronary heart disease (CHD), fatal and nonfatal stroke, and CVD (composite of CHD and stroke).ResultsBy year 6, mean fat intake decreased by 8.2% of energy intake in the intervention vs the comparison group, with small decreases in saturated (2.9%), monounsaturated (3.3%), and polyunsaturated (1.5%) fat; increases occurred in intakes of vegetables/fruits (1.1 servings/d) and grains (0.5 serving/d). Low-density lipoprotein cholesterol levels, diastolic blood pressure, and factor VIIc levels were significantly reduced by 3.55 mg/dL, 0.31 mm Hg, and 4.29%, respectively; levels of high-density lipoprotein cholesterol, triglycerides, glucose, and insulin did not significantly differ in the intervention vs comparison groups. The numbers who developed CHD, stroke, and CVD (annualized incidence rates) were 1000 (0.63%), 434 (0.28%), and 1357 (0.86%) in the intervention and 1549 (0.65%), 642 (0.27%), and 2088 (0.88%) in the comparison group. The diet had no significant effects on incidence of CHD (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.90-1.06), stroke (HR, 1.02; 95% CI, 0.90-1.15), or CVD (HR, 0.98; 95% CI, 0.92-1.05). Excluding participants with baseline CVD (3.4%), the HRs (95% CIs) for CHD and stroke were 0.94 (0.86-1.02) and 1.02 (0.90-1.17), respectively. Trends toward greater reductions in CHD risk were observed in those with lower intakes of saturated fat or trans fat or higher intakes of vegetables/fruits.ConclusionsOver a mean of 8.1 years, a dietary intervention that reduced total fat intake and increased intakes of vegetables, fruits, and grains did not significantly reduce the risk of CHD, stroke, or CVD in postmenopausal women and achieved only modest effects on CVD risk factors, suggesting that more focused diet and lifestyle interventions may be needed to improve risk factors and reduce CVD risk.Clinical Trials RegistrationClinicalTrials.gov Identifier: NCT00000611

Journal ArticleDOI
TL;DR: ABT-737 effectively kills acute myeloid leukemia blast, progenitor, and stem cells without affecting normal hematopoietic cells, suggesting that ABT- 737 could be a highly effective antileukemia agent when the mechanisms of resistance identified here are considered.

Journal ArticleDOI
TL;DR: Daily supplementation of calcium with vitamin D for seven years had no effect on the incidence of colorectal cancer among postmenopausal women, and the long latency associated with the development of colorescopy cancer, along with the seven-year duration of the trial, may have contributed to this null finding.
Abstract: Background Higher intake of calcium and vitamin D has been associated with a reduced risk of colorectal cancer in epidemiologic studies and polyp recurrence in polyp-prevention trials. However, randomized-trial evidence that calcium with vitamin D supplementation is beneficial in the primary prevention of colorectal cancer is lacking. Methods We conducted a randomized, double-blind, placebo-controlled trial involving 36,282 postmenopausal women from 40 Women’s Health Initiative centers: 18,176 women received 500 mg of elemental calcium as calcium carbonate with 200 IU of vitamin D3 twice daily (1000 mg of elemental calcium and 400 IU of vitamin D3) and 18,106 received a matching placebo for an average of 7.0 years. The incidence of pathologically confirmed colorectal cancer was the designated secondary outcome. Baseline levels of serum 25-hydroxyvitamin D were assessed in a nested case–control study. Results The incidence of invasive colorectal cancer did not differ significantly between women assigned to calcium plus vitamin D supplementation and those assigned to placebo (168 and 154 cases; hazard ratio, 1.08; 95 percent confidence interval, 0.86 to 1.34; P = 0.51), and the tumor characteristics were similar in the two groups. The frequency of colorectal-cancer screening and abdominal symptoms was similar in the two groups. There were no significant treatment interactions with baseline characteristics. Conclusions Daily supplementation of calcium with vitamin D for seven years had no effect on the incidence of colorectal cancer among postmenopausal women. The long latency associated with the development of colorectal cancer, along with the seven-year duration of the trial, may have contributed to this null finding. Ongoing follow-up will assess the longer-term effect of this intervention. (ClinicalTrials.gov number, NCT00000611.)

Journal ArticleDOI
16 Jun 2006-Science
TL;DR: The authors showed that climate warming will thaw permafrost, releasing trapped carbon from this high-latitude reservoir and further exacerbating global warming, and showed that carbon dioxide can be released from the frozen reservoir.
Abstract: Climate warming will thaw permafrost, releasing trapped carbon from this high-latitude reservoir and further exacerbating global warming.

Journal ArticleDOI
TL;DR: In this paper, the scale mismatch problem is defined as a mismatch between the scale of management and the scale(s) of the ecological processes being managed, where one or more functions of the social-ecological system are disrupted, inefficiencies occur, and/or important components of the system are lost.
Abstract: Scale is a concept that transcends disciplinary boundaries. In ecology and geography, scale is usually defined in terms of spatial and temporal dimensions. Sociological scale also incorporates space and time, but adds ideas about representation and organization. Although spatial and temporal location determine the context for social and ecological dynamics, social-ecological interactions can create dynamic feedback loops in which humans both influence and are influenced by ecosystem processes. We hypothesize that many of the problems encountered by societies in managing natural resources arise because of a mismatch between the scale of management and the scale(s) of the ecological processes being managed. We use examples from southern Africa and the southern United States to address four main questions: (1) What is a “scale mismatch?” (2) How are scale mismatches generated? (3) What are the consequences of scale mismatches? (4) How can scale mismatches be resolved? Scale mismatches occur when the scale of environmental variation and the scale of social organization in which the responsibility for management resides are aligned in such a way that one or more functions of the social-ecological system are disrupted, inefficiencies occur, and/or important components of the system are lost. They are generated by a wide range of social, ecological, and linked social-ecological processes. Mismatches between the scales of ecological processes and the institutions that are responsible for managing them can contribute to a decrease in social-ecological resilience, including the mismanagement of natural resources and a decrease in human well-being. Solutions to scale mismatches usually require institutional changes at more than one hierarchical level. Long-term solutions to scale mismatch problems will depend on social learning and the development of flexible institutions that can adjust and reorganize in response to changes in ecosystems. Further research is needed to improve our ability to diagnose, understand, and resolve scale mismatches in linked socialecological systems.

Journal ArticleDOI
01 Jan 2006-Displays
TL;DR: In this review, the general field of electro Chromism is introduced, with coverage of the types, applications, and chemical classes of electrochromic materials and the experimental methods that are used in their study.

Journal ArticleDOI
TL;DR: Modelling analyses indicate no clear spatial patterning and support the hypothesis that phylogeographical structure in diverse temperate taxa is complex and was not shaped by just a few barriers.
Abstract: Regional phylogeographical studies involving co-distributed animal and plant species have been conducted for several areas, most notably for Europe and the Pacific Northwest of North America. Until recently, phylogeographical studies in unglaciated eastern North America have been largely limited to animals. As more studies emerge for diverse lineages (including plants), it seems timely to assess the phylogeography across this region: (i) comparing and contrasting the patterns seen in plants and animals; (ii) assessing the extent of pseudocongruence; and (iii) discussing the potential applications of regional phylogeography to issues in ecology, such as response to climatic change. Unglaciated eastern North America is a large, geologically and topographically complex area with the species examined having diverse distributions. Nonetheless, some recurrent patterns emerge: (i) maritime - Atlantic vs. Gulf Coast; (ii) Apalachicola River discontinuity; (iii) Tombigbee River discontinuity; (iv) the Appalachian Mountain discontinuity; (v) the Mississippi River discontinuity; and (vi) the Apalachicola River and Mississippi River discontinuities. Although initially documented in animals, most of these patterns are also apparent in plants, providing support for phylogeographical generalizations. These patterns may generally be attributable to isolation and differentiation during Pleistocene glaciation, but in some cases may be older (Pliocene). Molecular studies sometimes agree with longstanding hypotheses of glacial refugia, but also suggest additional possible refugia, such as the southern Appalachian Mountains and areas close to the Laurentide Ice Sheet. Many species exhibit distinct patterns that reflect the unique, rather than the shared, aspects of species' phylogeographical histories. Furthermore, similar modern phylogeographical patterns can result from different underlying causal factors operating at different times (i.e. pseudocongruence). One underemphasized component of pseudocongruence may result from the efforts of researchers to categorize patterns visually - similar patterns may, in fact, not fully coincide, and inferring agreement may obscure the actual patterns and lead to erroneous conclusions. Our modelling analyses indicate no clear spatial patterning and support the hypothesis that phylogeographical structure in diverse temperate taxa is complex and was not shaped by just a few barriers.

Journal ArticleDOI
01 Oct 2006
TL;DR: This paper shows how the above desirable features can be achieved by designing the covariance matrix of the probing signal vector transmitted by the radar, and demonstrates the advantages of several MIMO transmit beampsattern designs, including a beampattern matching design and a minimum sidelobe beamp attern design, over their phased-array counterparts.
Abstract: A multiple-input multiple-output (MIMO) radar system, unlike a standard phased-array radar, can choose freely the probing signals transmitted via its antennas to maximize the power around the locations of the targets of interest, or more generally to approximate a given transmit beampattern, and also to minimize the cross-correlation of the signals reflected back to the radar by the targets of interest. In this paper, we show how the above desirable features can be achieved by designing the covariance matrix of the probing signal vector transmitted by the radar. Moreover, in a numerical study, we show that the proper choice of the probing signals can significantly improve the performance of adaptive MIMO radar techniques. Additionally, we demonstrate the advantages of several MIMO transmit beampattern designs, including a beampattern matching design and a minimum sidelobe beampattern design, over their phased-array counterparts.

Journal ArticleDOI
31 Mar 2006-Langmuir
TL;DR: Using these surface-modification schemes, fluorescent dye-doped silica nanoparticles can be more readily conjugated with biomolecules and used as highly fluorescent, sensitive, and reproducible labels in bioanalytical applications.
Abstract: In this article, a systematic study of the design and development of surface-modification schemes for silica nanoparticles is presented. The nanoparticle surface design involves an optimum balance of the use of inert and active surface functional groups to achieve minimal nanoparticle aggregation and reduce nanoparticle nonspecific binding. Silica nanoparticles were prepared in a water-in-oil microemulsion and subsequently surface modified via cohydrolysis with tetraethyl orthosilicate (TEOS) and various organosilane reagents. Nanoparticles with different functional groups, including carboxylate, amine, amine/phosphonate, poly(ethylene glycol), octadecyl, and carboxylate/octadecyl groups, were produced. Aggregation studies using SEM, dynamic light scattering, and zeta potential analysis indicate that severe aggregation among amine-modified silica nanoparticles can be reduced by adding inert functional groups, such as methyl phosphonate, to the surface. To determine the effect of various surface-modificati...


Journal ArticleDOI
TL;DR: In this article, Cohen et al. found that the PSS-10 is a reliable and valid instrument for assessment of perceived stress in college students and used it to measure perceived helplessness and self-efficacy.
Abstract: Because of increased stress conditions in college students, updated psychometrics of the Perceived Stress Scale, 10-item version (PSS-10; S. Cohen & G. Williamson, 1988) are necessary. Participants were 281 undergraduates at 3 public universities. An exploratory factor analysis revealed a 2-factor structure measuring Perceived Helplessness and Perceived Self-Efficacy. Normative results, internal consistencies, and construct validity were supported. The current findings reveal that the PSS-10 is a reliable and valid instrument for assessment of perceived stress in college students.