Undetected Blooms in Prince William Sound: Using Multiple Techniques to Elucidate the Base of the Summer Food Web

© 2015, Coastal and Estuarine Research Federation. Prince William Sound supports many commercially and culturally important species. The phytoplankton community dynamics which support and sustain the high biomass and diversity of this ecosystem are largely unknown. The aim of this study was to describe the phytoplankton community composition during the summer, the time at which this system supports many additional migrants and commercially important fisheries. Phytoplankton community composition (pigments), dissolved nutrients, Secchi depth, total and particulate organic carbon and nitrogen, and export to deep water were measured during the summers of 2008–2010. In addition, natural abundance stable isotopes (δ13C and δ15N) of particulate organic matter (POM) and faunal samples were measured in 2010. The analysis of the phytoplankton community composition using multivariate statistics showed that changes over the summer were driven by changes in the proportion of the dominant groups: diatoms, dinoflagellates, cyanobacteria, cryptophytes, chlorophytes, and prasinophytes. These changes were driven by changes in nutrients including an organic nitrogen source, phosphate, and silica and correspond to shifts in particulate concentrations. A consistent pattern was observed each year: a large Noctiluca sp. bloom in June concurrent with low nutrients, low diversity, and high particulate organic carbon (POC) concentrations was followed by a shift in the phytoplankton community to a more diverse smaller size class community in July and equilibrating in August. This annual summer bloom could be an important contributor to the energy and nutrient inputs at the base of the regional marine food web

An investigation into the current management of hypertension in Hong Kong: a two-phase study

published_or_final_versio

Stringy Stability of Charged Dilaton Black Holes with Flat Event Horizon

Electrically charged black holes with flat event horizon in anti-de Sitter space have received much attention due to various applications in Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence, from modeling the behavior of quark-gluon plasma to superconductor. Crucial to the physics on the dual field theory is the fact that when embedded in string theory, black holes in the bulk may become vulnerable to instability caused by brane pair-production. Since dilaton arises naturally in the context of string theory, we study the effect of coupling dilaton to Maxwell field on the stability of flat charged AdS black holes. In particular, we study the stability of Gao-Zhang black holes, which are locally asymptotically anti-de Sitter. We find that for dilaton coupling parameter $\alpha$ > 1, flat black holes are stable against brane pair production, however for 0 < $\alpha$ < 1, the black holes eventually become unstable as the amount of electrical charges is increased. Such instability however, behaves somewhat differently from that of flat Reissner-Nordstr\"om black holes. In addition, we prove that the Seiberg-Witten action of charged dilaton AdS black hole of Gao-Zhang type with flat event horizon (at least in 5-dimension) is always logarithmically divergent at infinity for finite values of $\alpha$, and is finite and positive in the case $\alpha$ tends to infinity . We also comment on the robustness of our result for other charged dilaton black holes that are not of Gao-Zhang type.Comment: Fixed some confusions regarding whether part of the discussions concern electrically charged hole or magnetically charged one. No changes to the result

Personalized Drug Dosage – Closing the Loop

A brief account is given of various approaches to the individualization of drug dosage, including the use of pharmacodynamic markers, therapeutic monitoring of plasma drug concentrations, genotyping, computer-guided dosage using ‘dashboards’, and automatic closed-loop control of pharmacological action. The potential for linking the real patient to his or her ‘virtual twin’ through the application of physiologically-based pharmacokinetic modeling is also discussed

Combination Therapy Is Superior to Sequential Monotherapy for the Initial Treatment of Hypertension:A Double-Blind Randomized Controlled Trial

Background: Guidelines for hypertension vary in their preference for initial combination therapy or initial monotherapy, stratified by patient profile; therefore, we compared the efficacy and tolerability of these approaches. Methods and Results: We performed a 1‐year, double‐blind, randomized controlled trial in 605 untreated patients aged 18 to 79 years with systolic blood pressure (BP) ≥150 mm Hg or diastolic BP ≥95 mm Hg. In phase 1 (weeks 0–16), patients were randomly assigned to initial monotherapy (losartan 50–100 mg or hydrochlorothiazide 12.5–25 mg crossing over at 8 weeks), or initial combination (losartan 50–100 mg plus hydrochlorothiazide 12.5–25 mg). In phase 2 (weeks 17–32), all patients received losartan 100 mg and hydrochlorothiazide 12.5 to 25 mg. In phase 3 (weeks 33–52), amlodipine with or without doxazosin could be added to achieve target BP. Hierarchical primary outcomes were the difference from baseline in home systolic BP, averaged over phases 1 and 2 and, if significant, at 32 weeks. Secondary outcomes included adverse events, and difference in home systolic BP responses between tertiles of plasma renin. Home systolic BP after initial monotherapy fell 4.9 mm Hg (range: 3.7–6.0 mm Hg) less over 32 weeks (P&lt;0.001) than after initial combination but caught up at 32 weeks (difference 1.2 mm Hg [range: −0.4 to 2.8 mm Hg], P=0.13). In phase 1, home systolic BP response to each monotherapy differed substantially between renin tertiles, whereas response to combination therapy was uniform and at least 5 mm Hg more than to monotherapy. There were no differences in withdrawals due to adverse events. Conclusions: Initial combination therapy can be recommended for patients with BP &gt;150/95 mm Hg. Clinical Trial Registration URL: http://www.ClinicalTrials.gov. Unique identifier: NCT00994617

Does chocolate reduce blood pressure? A meta-analysis

BackgroundDark chocolate and flavanol-rich cocoa products have attracted interest as an alternative treatment option for hypertension, a known risk factor for cardiovascular disease. Previous meta-analyses concluded that cocoa-rich foods may reduce blood pressure. Recently, several additional trials have been conducted with conflicting results. Our study summarises current evidence on the effect of flavanol-rich cocoa products on blood pressure in hypertensive and normotensive individuals.MethodsWe searched Medline, Cochrane and international trial registries between 1955 and 2009 for randomised controlled trials investigating the effect of cocoa as food or drink compared with placebo on systolic and diastolic blood pressure (SBP/DBP) for a minimum duration of 2 weeks. We conducted random effects meta-analysis of all studies fitting the inclusion criteria, as well as subgroup analysis by baseline blood pressure (hypertensive/normotensive). Meta-regression analysis explored the association between type of treatment, dosage, duration or baseline blood pressure and blood pressure outcome. Statistical significance was set at P ResultsFifteen trial arms of 13 assessed studies met the inclusion criteria. Pooled meta-analysis of all trials revealed a significant blood pressure-reducing effect of cocoa-chocolate compared with control (mean BP change +/- SE: SBP: -3.2 +/- 1.9 mmHg, P = 0.001; DBP: -2.0 +/- 1.3 mmHg, P = 0.003). However, subgroup meta-analysis was significant only for the hypertensive or prehypertensive subgroups (SBP: -5.0 +/- 3.0 mmHg; P = 0.0009; DBP: -2.7 +/- 2.2 mm Hg, P = 0.01), while BP was not significantly reduced in the normotensive subgroups (SBP: -1.6 +/- 2.3 mmHg, P = 0.17; DBP: -1.3 +/- 1.6 mmHg, P = 0.12). Nine trials used chocolate containing 50% to 70% cocoa compared with white chocolate or other cocoa-free controls, while six trials compared high- with low-flavanol cocoa products. Daily flavanol dosages ranged from 30 mg to 1000 mg in the active treatment groups, and interventions ran for 2 to 18 weeks. Meta-regression analysis found study design and type of control to be borderline significant but possibly indirect predictors for blood pressure outcome.ConclusionOur meta-analysis suggests that dark chocolate is superior to placebo in reducing systolic hypertension or diastolic prehypertension. Flavanol-rich chocolate did not significantly reduce mean blood pressure below 140 mmHg systolic or 80 mmHg diastolic.Karin Ried, Thomas Sullivan, Peter Fakler, Oliver R. Frank and Nigel P. Stock

Effect of garlic on blood pressure: A systematic review and meta-analysis

The electronic version of this article is the complete one and can be found online at the publisher's website.Background: Non-pharmacological treatment options for hypertension have the potential to reduce the risk of cardiovascular disease at a population level. Animal studies have suggested that garlic reduces blood pressure, but primary studies in humans and non-systematic reviews have reported mixed results. With interest in complementary medicine for hypertension increasing, it is timely to update a systematic review and meta-analysis from 1994 of studies investigating the effect of garlic preparations on blood pressure. Methods: We searched the Medline and Embase databases for studies published between 1955 and October 2007. Randomised controlled trials with true placebo groups, using garlic-only preparations, and reporting mean systolic and/or diastolic blood pressure (SBP/DBP) and standard deviations were included in the meta-analysis. We also conducted subgroup meta-analysis by baseline blood pressure (hypertensive/normotensive), for the first time. Meta-regression analysis was performed to test the associations between blood pressure outcomes and duration of treatment, dosage, and blood pressure at start of treatment. Results: Eleven of 25 studies included in the systematic review were suitable for meta-analysis. Meta-analysis of all studies showed a mean decrease of 4.6 ± 2.8 mm Hg for SBP in the garlic group compared to placebo (n = 10; p = 0.001), while the mean decrease in the hypertensive subgroup was 8.4 ± 2.8 mm Hg for SBP (n = 4; p < 0.001), and 7.3 ± 1.5 mm Hg for DBP (n = 3; p < 0.001). Regression analysis revealed a significant association between blood pressure at the start of the intervention and the level of blood pressure reduction (SBP: R = 0.057; p = 0.03; DBP: R = -0.315; p = 0.02). Conclusion: Our meta-analysis suggests that garlic preparations are superior to placebo in reducing blood pressure in individuals with hypertension.Karin Ried, Oliver R. Frank, Nigel P. Stocks, Peter Fakler and Thomas Sulliva