Tests of ordered hypotheses in linkage in heredity

The asymptotic null distribution of the likelihood ratio test for two cases of ordered hypotheses in a particular genetic model is considered. A simple iterative process is proposed in order to get the restricted estimates. It is shown that both tests have asymptotically a chi-bar squared distribution and the same size. A simulation study is also conducted in order to compare the usual unrestricted test with the corresponding one of ordered hypotheses. Finally, the results are extended to some special cases.     

Proper holomorphic maps between Reinhardt domains and strictly pseudoconvex domains

LetR be a Reinhardt domain andD a bounded simply connected strictly pseudoconvex domain withC ^∞ boundary. We prove that any proper holomorphic mapF:R →D is, up to biholomorphism ofD, of the form \((z_1^{d_1 } , z_2^{d_2 } , \ldots , z_n^{d_n } )\) withd ₁,d ₂,…,d _n ∈ IN.     

Cathodic behaviour of nickel(II) in acetonitrile in the presence of carbon monoxide and substituted phosphines

Summary The reduction of nickel perchlorate in the presence of carbon monoxide and substituted phosphines or diphosphines has been studied in acetonitrile by cyclic voltammetry. The results show that only mono- and bis-carbonylphosphinenickel(O) complexes are formed, while no evidence for the formation of carbonyl-nickel(I) and -nickel(II) species was obtained. Although the oxidation processes are not reversible, a good correlation between the anodic peak potentials relative to nickel(O) complexes and the -donor--acceptor abilities of the phosphines employed was observed.     

A simple procedure for the chromatographic analysis of nanoliter samples

A simple method for the analysis of nanoliter droplets is proposed, which is profitable when larger samples cannot be collected as, for instance, in the case of several biological fluids and particularly in clinical chemistry. A glass capillary associated to a micromanipulator is used to collect submicroliter volumes which are partially transferred into transparent polymeric tubings with known internal diameters (120–178 μm), where the volumes sampled are measured by meniscus collimations with a collimator microscope at suitable magnification. Both ends of these tubings are preliminarily equipped with ferrules and fittings, so as to make them suitable for connection as the loop to a conventional high-pressure injection valve. The reliability of this procedure has been tested for the analysis of Na⁺, K⁺ and Ca²⁺ present in minute synthetic standard samples (10–200 nL) by a conventional ion-chromatographic instrumentation. Relative standard deviations in peak area measurements (5–6%) are discussed in terms of the whole approximation affecting volume measurements, which depends on both the inconstancy of the inner diameter of the polymeric tubings employed and the uncertainty characterizing meniscus collimations. The proposed procedure can be easily extended to the determination of any organic or inorganic species present in very small samples, provided that their detection can be achieved by any chromatographic approach or, more generally, by flow injection analysis. Received: 16 June 1997 / Revised: 12 August 1997 / Accepted: 14 August 1997     

Novel Iron Oxide Nanoparticles Induce Ferroptosis in a Panel of Cancer Cell Lines

The use of nanomaterials rationally engineered to treat cancer is a burgeoning field that has reported great medical achievements. Iron-based polymeric nano-formulations with precisely tuned physicochemical properties are an expanding and versatile therapeutic strategy for tumor treatment. Recently, a peculiar type of regulated necrosis named ferroptosis has gained increased attention as a target for cancer therapy. Here, we show for the first time that novel iron oxide nanoparticles coated with gallic acid and polyacrylic acid (IONP–GA/PAA) possess intrinsic cytotoxic activity on various cancer cell lines. Indeed, IONP–GA/PAA treatment efficiently induces ferroptosis in glioblastoma, neuroblastoma, and fibrosarcoma cells. IONP–GA/PAA-induced ferroptosis was blocked by the canonical ferroptosis inhibitors, including deferoxamine and ciclopirox olamine (iron chelators), and ferrostatin-1, the lipophilic radical trap. These ferroptosis inhibitors also prevented the lipid hydroperoxide generation promoted by the nanoparticles. Altogether, we report on novel ferroptosis-inducing iron encapsulated nanoparticles with potent anti-cancer properties, which has promising potential for further in vivo validation.     

Assessment of pharmacokinetic interaction between piracetam and l‐carnitine in healthy subjects

A rapid, sensitive and specific method for quantifying piracetam in human plasma using Piracetam d‐8 as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by one‐step precipitation of protein using an acetonitrile (100%). The extracts were analyzed by high‐performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC‐MS/MS). The method had a chromatographic run time of 3.8 min and a linear calibration curve over the range 0.5–50 µg/mL (r > 0.99). This LC‐MS‐MS procedure was used to assess the bioavailability of two piracetam formulations: piracetam + l‐carnitine (Piracar®; 270/330 mg tablet) and piracetam (Nootropil®; 800 mg tablet) in healthy volunteers of both sexes. The geometric means with corresponding 90% confidence interval (CI) for test/reference percentage ratios were 88.49% (90% CI = 81.19 – 96.46) for peak concentration/dose and 102.55% (90% CI = 100.62 – 104.51) for AUC_inf/dose. The limit of quantitation of 0.5 µg/mL is well suited for pharmacokinetic studies in healthy volunteers. It was concluded that piracetam (Piracar®; 270/330 mg tablet) has a bioavailability equivalent to the piracetam (Nootropil®; 800 mg tablet) formulation with regard to both the rate and the extent of absorption. Copyright © 2015 John Wiley & Sons, Ltd.     

Separation of isomeric disaccharides by traveling wave ion mobility mass spectrometry using CO2 as drift gas

The use of CO₂ as a massive and polarizable drift gas is shown to greatly improve peak‐to‐peak resolution (R_p‐p), as compared with N₂, for the separation of disaccharides in a Synapt G2 traveling wave ion mobility cell. Near or baseline R_p‐p was achieved for three pairs of sodiated molecules of disaccharide isomers, that is, cellobiose and sucrose (R_p‐p = 0.76), maltose and sucrose (R_p‐p = 1.04), and maltose and lactose (R_p‐p = 0.74). Ion mobility mass spectrometry using CO₂ as the drift gas offers therefore an attractive alternative for fast and efficient separation of isomeric disaccharides. Copyright © 2012 John Wiley & Sons, Ltd.     

Characterization of the raw essential oil eugenol extracted from <Emphasis Type="Italic">Syzygium</Emphasis> <Emphasis Type="Italic">aromaticum</Emphasis> L.

Eugenol is the main volatile compound extracted oil from clove bud, Syzygium aromaticum L., and used in traditional medicine, as a bactericide, fungicide, anesthetic, and others. Its extraction was performed using hydrodistillation which is the most common extraction technique. Its components and thermal behavior were evaluated using gas chromatography (GC) and differential scanning calorimetry (DSC), which provide a better characterization of these natural compounds. This extracted product was compared to the standard eugenol results. The GC results suggested ~90% eugenol was found in the total extracted oil, and some of its boiling characteristics were 270.1 °C for peak temperature and 244.1 J g⁻¹ for the enthalpy variation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Heat transfer between two nanoparticles through near field interaction

We introduce a thermal conductance by using the fluctuation-dissipation theorem to analyze the heat transfer between two nanoparticles separated by a submicron distance. Using either a molecular dynamics technique or a model based on the Coulomb interaction between fluctuating dipoles, we derive the thermal conductance. Both models agree for distances larger than a few diameters. For separation distances smaller than the particle diameter, we find a transition regime characterized by a thermal conductance larger than the contact conductance.