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The present paper reports on the capability of high-resolution inductively coupled plasma mass spectrometry (HR-ICPMS) for the accurate and precise determination of isotope ratios of which at least one of the isotopes involved is spectrally interfered when measured at low resolution, using Cu as a typical example. When a commercially available Finnigan MAT Element high-resolution ICP-mass spectrometer operated at a resolution setting of 3000 is used, careful selection of the measurement conditions allows a 63Cu/65Cu or 206Pb/207Pb isotope ratio precision of [approximately]0.1% (RSD for n = 10) at sufficiently high count rates ([greater than or equal to]100 000 counts/s). In this work, Cu isotope ratios were determined both in (i) an Antarctic sediment digest and in (ii) a human serum reference material. Even at the low Cu concentration level in the Antarctic sediment digests ([approximately]10 [[micro]gram]/L), the 63Cu/65Cu isotope ratio could be measured with an RSD of [less than or equal to]0.6% (n = 5). Although both isotopes involved were severely spectrally interfered when measured at low resolution, measurement at R = 3000 resulted in an isotope ratio that agreed within the measurement uncertainty with the expected natural isotopic abundance ratio. For the human serum reference material, the sample preparation was limited to 10-fold dilution with 0.14 M HN[O.sub.3], resulting in solutions containing [approximately]100 [[micro]gram]/L Cu. The 63Cu/65Cu isotope ratio was measured with an RSD of 0.3% (n = 5) and agreed within the measurement uncertainty with the value expected on the basis of the natural isotopic abundances. Finally, on the basis of the corresponding mass spectra at R = 3000, for both samples an attempt was made to identify the polyatomic ions that spectrally interfere with the Cu ion signals at low resolution. For the Antarctic sediment digest, these interfering ions were speculatively identified as 40[Ar.sup.23][Na.sup.+], 28[Si.sup.35][Cl.sup.+], and 23[Na.sub.2]16[O.sup.1][H.sup.+] for 63[Cu.sup.+] and 30Si35[Cl.sup.+], 28[Si.sup.37][Cl.sup.+], and 23[Na.sub.2]19[F.sup.+] for 65[Cu.sup.+]. For the human serum reference material, the interfering signals were attributed to 40[Ar.sup.23][Na.sup.+], 31[P.sup.16][[O.sub.2].sup.+], and 23[Na.sub.2]16[O.sup.1][H.sup.+] for 63[Cu.sup.+] and to 32[S.sup.16][O.sub.2]1[H.sup.+] for 65[Cu.sup.+].

An adaptive controller with improved performance characteristics is introduced. The proposed controller extends recent results in this area since it achieves performance improvement of the zero-state output error in the presence of some uncertainty on the high-frequency gain of the plant.

The problem of design and evaluation of binary hypothesis tests based on a set of available observations is considered. A so-called structured adaptive network (SAN) configuration for the modeling and implementation of a wide class of such tests is introduced. A general framework for the analysis and performance evaluation of a SAN is developed.

In this paper, a new method for the computation of the optimal step in gradient algorithms for a class of linear quadratic optimal control problems is presented. This method improves the convergence of the gradient algorithms and is optimal, i.e., it outperforms any other step searching scheme in the above class of problems.

There is no agreement of data on the subject of implant failure and the development of osteonecrosis in patients receiving antiresorptive agents. The purpose of this systematic review is to evaluate whether dental implants placed in patients on antiresorptive medication have an increased failure rate and whether the implant placement or the implant existence are risk factors for developing medication-related osteonecrosis of the jaw (MRONJ). An electronic search was conducted in PubMed/Medline, and all publications fulfilling the inclusion criteria were included. The search was completed by a hand research of the references cited in all electronic identified publications, resulting in 411 articles. Based on the inclusion criteria, 32 studies were included, with a total of 5221 patients, 12 751 implants, 618 cases of implants loss, and 136 cases of MRONJ analyzed. Because of the small number of studies, most of which were characterized by a low level of quality, it cannot be established that the use of antiresorptive medication affects dental implant survival rates. The risk of MRONJ as an early or late complication is also not well established. Therefore, successful dental implant procedures in patients receiving antiresorptive medication might be possible, but more studies need to be carried out in the future to verify this topic. Apart from intravenous antiresorptive drugs, which remain an absolute contraindication, the use of antiresorptive medication is not a contraindication to dental implantology, but it must be accompanied by careful treatment planning, informing patients about possible complications, and essential long follow-up periods. [ABSTRACT FROM AUTHOR]

In this study, the effect of increased soil moisture on the nutritional status of two key commercial avocado (Persea americana Μill.) cultivars, 'Fuerte' and 'Hass', was examined. The results revealed that prolonged exposure of plants to high soil water content conditions (waterlogging) reduced the total nutrient content (absolute quantity) of almost all of the nutrients in scion's tissues (leaves and stems) of both cultivars. The decrease of nutrient content in the 'Fuerte' leaves was more prominent/severe compared to the 'Hass' leaves, which could be the outcome of the reported higher sensitivity of the cultivar to soil waterlogged conditions in previous studies. Interestingly, the inability of 'Fuerte' avocado plants to withstand high soil moisture conditions was not reflected in the relative concentrations of most nutrients, both in leaves and stems. Indeed, significantly higher concentrations of P, K, B, Fe, and Zn were found in the leaves of 'Fuerte' waterlogged plants than in well-watered ones. This fact reveals that under marginal/stressful conditions, like waterlogging, nutrient concentration in tissues does not reflect potential negative effects on total nutrient uptake of avocado plants, obviously due to concentrated nutrient phenomena primarily created by the stress-dependent growth inhibition. Therefore, total nutrient content is proposed as a more representative indicator for assessing plant response to waterlogged conditions. [ABSTRACT FROM AUTHOR]