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This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). <This article has been retracted at the request of the Editors-in-Chief. A journal-wide investigation by Elsevier's Research Integrity & Publishing Ethics team identified violations of the journal's policies on conflict of interest related to the submission and review of this paper. Review of this submission was handled by Guest Editor Hassan Karimi-Maleh despite an extensive record of collaboration, including co-publication, with one of the paper co-authors (Fatemeh Karimi). Acceptance of the article was solely based upon the positive advice of reviewers who were closely linked to two of the authors (Karimi, Mehdi Baghayeri). This compromised the editorial process and breached the journal's policies. The authors disagree with this retraction and dispute the grounds for it.>.
Current hypertension guidelines fail to provide a recommendation on when-to-treat, thus disregarding relevant circadian rhythms that regulate blood pressure (BP) level and 24 h patterning and medication pharmacokinetics and pharmacodynamics. The ideal purpose of ingestion-time (chronopharmacology, i.e. biological rhythm-dependent effects on the kinetics and dynamics of medications, and chronotherapy, i.e. the timing of pharmaceutical and other treatments to optimize efficacy and safety) trials should be to explore the potential impact of endogenous circadian rhythms on the effects of medications. Such investigations and outcome trials mandate adherence to the basic standards of human chronobiology research. In-depth review of the more than 150 human hypertension pharmacology and therapeutic trials published since 1974 that address the differential impact of upon-waking/morning versus at-bedtime/evening schedule of treatment reveals diverse protocols of sometimes suboptimal or defective design and conduct. Many have been "time-of-day," i.e. morning versus evening, rather than circadian-time-based, and some relied on wake-time office BP rather than around-the-clock ambulatory BP measurements (ABPM). Additionally, most past studies have been of too small sample size and thus statistically underpowered. As of yet, there has been no consensual agreement on the proper design, methods and conduct of such trials. This Position Statement recommends ingestion-time hypertension trials to follow minimum guidelines: (i) Recruitment of participants should be restricted to hypertensive individuals diagnosed according to ABPM diagnostic thresholds and of a comparable activity/sleep routine. (ii) Tested treatment-times should be selected according to internal biological time, expressed by the awakening and bed times of the sleep/wake cycle. (iii) ABPM should be <i>the</i> primary or sole method of BP assessment. (iv) The minimum-required features for analysis of the ABPM-determined 24 h BP pattern ought to be the <i>asleep</i> (not "nighttime") <i>BP mean</i> and <i>sleep-time relative BP decline</i>, calculated in reference to the activity/rest cycle per individual. (v) ABPM-obtained BP means should be derived by the so-called <i>adjusted calculation</i> procedure, not by inaccurate arithmetic averages. (vi) ABPM should be performed with validated and calibrated devices at least hourly throughout two or more consecutive 24 h periods (48 h in total) to achieve the highest reproducibility of mean wake-time, sleep-time and 48 h BP values plus the reliable classification of dipping status. (vii) Calculation of minimum required sample size in adherence with proper statistical methods must be provided. (viii) Hypertension chronopharmacology and chronotherapy trials should preferably be randomized double-blind, randomized open-label with blinded-endpoint, or crossover in design, the latter with sufficient washout period between tested treatment-time regimens.
Microgel grow-bags: Surface-enhanced Raman scattering (SERS)-active bimetallic core–shell spheres can be grown inside poly(N-isopropylacrylamide) (pNIPAM) microgels (see figure). Detailed facts of importance to specialist readers are published as "Supporting Information". Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
The preparation of gold particle coated silica microspheres is described and the optical absorption spectra for various surface coverages of gold particles are presented. Onion-shell particles with the structure silica-gold-silica are also described. An effective medium model is used to quantify the surface plasmon shifts observed in such particles, which predicts the shifts in surface plasmon band for both solvent refractive index and surface coverage. The resultant microspheres exhibit absorption spectra resembling those of the isolated nanocrystals. However they possess extinction cross-sections orders of magnitude higher than the nanocrystals and can be centrifuged and redispersed more easily than the parent nanocrystals. The same effect can be obtained by coating silica spheres with gold nanorods, so that the plasmon absorption band can be tuned through the visible and NIR wavelength range. It is proposed that such micron-sized "nanoparticles" provide a practical means to amplify the unique optical properties of nanocrystals and make them more amenable to colloid processing.
Abstract: Maintaining the levels of genetic variability in captive populations of endangered species is an important objective of conservation biology. Because of the generally low sizes of captive populations, genetic drift is the main cause of loss of diversity. Several simple management rules, such as equalization of contributions from parents to the next generation, are recommended for minimizing genetic drift, but it cannot be removed completely because of the unavoidable random segregation of heterozygotes. Recent advances in reproductive technology, particularly developed for mammals, are now making a reality of the possibility of using more than one cell from a single meiosis in reproduction. With this technology it is possible to reduce or even completely cancel the genetic drift caused by segregation of heterozygotes. We evaluated the theoretical benefits of the use of such technologies to conservation biology. The effective population size can be increased enormously and, consequently, the amount of drift can be greatly reduced if manipulations in reproduction are made.
