Iterative actions of normal operators

Let $A$ be a normal operator in a Hilbert space $\mathcal{H}$, and let $\mathcal{G} \subset \mathcal{H}$ be a countable set of vectors. We investigate the relations between $A$, $\mathcal{G}$ , and $L$ that makes the system of iterations $\{A^ng: g\in \mathcal{G},\;0\leq n< L(g)\}$ complete, Bessel, a basis, or a frame for $\mathcal{H}$. The problem is motivated by the dynamical sampling problem and is connected to several topics in functional analysis, including, frame theory and spectral theory. It also has relations to topics in applied harmonic analysis including, wavelet theory and time-frequency analysis.Comment: 14 pages, 0 figure

Electronic structure of the c(4 x 2) reconstructed Ge(001) surface

We investigate the electronic structure of the c(4 x 2) reconstructed Ge(001) surface using band structure calculations based on density functional theory and the generalized gradient approximation. In particular, we take into account the details of surface reconstruction by means of well relaxed crystal structures. The surface electronic states are identified and the local density of states is compared to recent data from scanning tunneling spectroscopy. We obtain almost perfect agreement between theory and experiment for both the occupied and unoccupied states, which allows us to clarify the interpretation of the experimental data.Comment: 4 pages, 3 figures, accepted by Chem. Phys. Let

Oncoplastic breast consortium recommendations for mastectomy and whole breast reconstruction in the setting of post-mastectomy radiation therapy

Aim Demand for nipple- and skin- sparing mastectomy (NSM/SSM) with immediate breast reconstruction (BR) has increased at the same time as indications for post-mastectomy radiation therapy (PMRT) have broadened. The aim of the Oncoplastic Breast Consortium initiative was to address relevant questions arising with this clinically challenging scenario. Methods A large global panel of oncologic, oncoplastic and reconstructive breast surgeons, patient advocates and radiation oncologists developed recommendations for clinical practice in an iterative process based on the principles of Delphi methodology. Results The panel agreed that surgical technique for NSM/SSM should not be formally modified when PMRT is planned with preference for autologous over implant-based BR due to lower risk of long-term complications and support for immediate and delayed-immediate reconstructive approaches. Nevertheless, it was strongly believed that PMRT is not an absolute contraindication for implant-based or other types of BR, but no specific recommendations regarding implant positioning, use of mesh or timing were made due to absence of high-quality evidence. The panel endorsed use of patient-reported outcomes in clinical practice. It was acknowledged that the shape and size of reconstructed breasts can hinder radiotherapy planning and attention to details of PMRT techniques is important in determining aesthetic outcomes after immediate BR. Conclusions The panel endorsed the need for prospective, ideally randomised phase III studies and for surgical and radiation oncology teams to work together for determination of optimal sequencing and techniques for PMRT for each patient in the context of BR

Agronomic biofortification of cereals with zinc: a review

Zinc (Zn) still represents an important health problem in developing countries, caused mainly by inadequate dietary intake. A large consumption of cereal-based foods with small concentrations and low bioavailability of Zn is the major reason behind this problem. Modern cultivars of cereals have inherently very small concentrations of Zn and cannot meet the human need for Zn. Today, up to 50% of wheat-cultivated soil globally is considered poor in bioavailable Zn. Agricultural strategies that are used to improve the nutritional value of crop plants are known as biofortification strategies. They include genetic biofortification, which is based on classical plant breeding and genetic engineering for larger nutrient concentrations, and greater agronomic biofortification, which is based on optimized fertilizer applications. This review focuses on agronomic biofortification with Zn, which has proved to be very effective for wheat and also other cereal crops including rice. Molecular and genetic research into Zn uptake, transport and grain deposition in cereals are critically important for identifying ‘bottlenecks’ in the biofortification of food crops with Zn. Transgenic plants with large Zn concentrations in seeds are often tested under controlled laboratory or glasshouse conditions with sufficient available Zn in the growth medium for the entire growth period. However, they might not always show the same performance under ‘real-world’ conditions with limited chemical availability of Zn and various stress factors such as drought. What purpose can an upgraded transport and storage system serve if the amount of goods to be transported and stored is limited anyway? Given the fact that the Zn concentrations required to achieve a measurable impact on human health are well above those required to avoid any loss of yield from Zn deficiency, providing crop plants with sufficient Zn through the soil and foliar fertilizer strategy under field conditions is critically important for biofortification efforts

First record of three plant parasitic nematode species from Mount Ararat (Ağrı) in Turkey

In this study, plant parasitic nematode fauna from Mount Ararat was determined according to altitude. A total of 30 soil samples were taken in 2013 during summer. Nematodes were extracted by a modified Baermann funnel technique. Nematodes were identified by morphology, morphometric and phylogenetic analysis based on sequences of the D2-D3 and ITS1-rRNA gene sequences. Permanent slides of individuals were made and species-specific characters were screened by scanning electron microscopy (SEM). SEM studies were processed at the Department of Animal Biology, Vegetal Biology and Ecology, SEM laboratory University of Jaén in Spain during 2014. A total of 19 plant parasitic nematodes were identified from Mount Ararat. Three plant parasitic nematodes Rotylenchus conicaudatus Atighi et al., 2011 (Nematoda: Hoplolaimidae), Heterodera trifolii Goffart, 1932 (Nematoda: Heteroderidae) and Tylenchorhynchus mangiferae (Luqman & Khan, 1986) (Nematoda: Belonolaimidae) from this study are new records for plant parasitic nematode fauna of the Turkish. © 2019 Entomological Society of Turkey. All rights reserved

Biofortification of durum wheat with zinc through soil and foliar applications of nitrogen

Increasing zinc (Zn) concentration of cereal grains is a global challenge to alleviate Zn deficiency-related health problems in humans caused by low dietary Zn intake. This study investigated the effects of soil- and foliar-applied nitrogen (N) and Zn fertilizers on grain Zn accumulation of durum wheat (Triticum durum) grown on a Zn-deficient soil. In addition, localization of Zn and protein within durum wheat grain was Studied by using Bradford reagent for protein and dithizone (diphenyl thiocarbazone) for Zn. Grain Zn concentration was greatly enhanced by soil or foliar applications of Zn. When Zn supply was adequately high, both soil and foliar N applications improved grain Zn concentration. Consequently, there was a significant positive correlation between grain concentrations of Zn and N, when Zn supply wag not limiting. Protein and Zn staining studies showed co-localization of Zn and protein within grain, particularly in the embryo and aleurone. Results indicate that N and Zn fertilization have a synergistic effect on grain Zn concentration. Possibly, increasing N supply contributes to grain Zn concentration by affecting the levels of Zn-chelating nitrogenous compounds or the abundance of Zn transporters. Our results suggest that nitrogen management can be an effective agronomic tool to improve grain Zn concentration

Assessment of the quality losses of fresh fig fruits during transportation [Taze İncir Meyvesinin Taşi{dotless}nmasi{dotless} Sirasinda Oluşan Kalite Kaybinin Deg`erlendirilmesi]

Turkey is one of the main fig fruits producers in the World. The protection of the fig fruit quality in the chains from harvesting to marketing is very important. Vibration often causes some damages to perishable fruits in transportation and reduces their quality. The fruit injury due to vibration is related to the transportation characteristics of vehicles, packaging boxes and the conditions of the roads. The objective of this study was to investigate the effectiveness of packaging box by different materials to decrease the damages of vertical vibration on the quality of three fresh fig varieties (Yediveren, Sarilop and Bursa Black) during transportation. The experiments were carried out in two stages. In the first stage; the frequency and acceleration values of truck were determined during the real transportation. In the second stage, these values were applied on the simulator (shaker) to examine the effect of vibration on fresh figs packaged with three different boxes. The results showed that the cardboard packaging box was not proper for transporting of the fresh fig fruits in all road conditions. The mass loss of fresh fig fruits packed with cardboard box were found to be 2.5 times more than extruded and expanded polystyrene boxes at 16 Hz frequency and 2.54 m s-2 acceleration. Sarilop fig variety was more damaged under the off-road. For long highway road conditions, Bursa Black fig variety was found the most affected fig variety. © Ankara Üniversitesi Ziraat Fakültesi