An improved quadratic program for unweighted Euclidean 1-center location problem

AbstractIn this paper, an improved quadratic programing formulation for the solution of unweighted Euclidean 1-center location problem is presented. The original quadratic program is proposed by Nair and Chandrasekaran in 1971. Besides, they proposed a geometric approach for problem solving. Then, they concluded that the geometric approach is more efficient than the quadratic program. This conclusion is true only when all decision variables are treated as nonnegative variables. To improve the quadratic program, one of those variables should be an unrestricted variable as it is presented here. Numerically we proved that the improved quadratic program leads to the optimal solution of the problem in parts of second regardless of the size of the problem. Moreover, constrained version of the problem is solved optimally via the improved quadratic program in parts of second

The effect of dietary supplementation of calcium pidolate with or without vitamin D metabolite on production performance and egg quality in commercial laying hens

Two experiments were conducted on commercial layer hens to study the effects of dietary supplementation with two levels of 25-hydroxycholecalciferol (25(OH)D₃) and two levels of calcium pidolate (with or without 25(OH)D₃) on production performance and egg quality. Experiment 1 was conducted using 90 Hy-Line Brown layer hens from 19 to 80 weeks of age and commenced in November 2012. Birds were divided into three groups of 30 hens as follows: group A (control group) fed with normal commercial layer mash feed, and groups B and C (treated groups) fed with normal commercial layer mash feed plus 0.5 g of 25(OH)D3 [premix (68.9 μg 25(OH)D₃)] per kg of feed and 1 g of 25(OH)D₃ [premix (137.8 μg 25(OH)D₃)] per kg of feed, respectively. Experiment 2 was conducted using 147 Lohmann Brown layer hens from 21 to 80 weeks of age and commenced in March 2014

Deletion of the Ste20-like kinase SLK in skeletal muscle results in a progressive myopathy and muscle weakness

Background The Ste20-like kinase, SLK, plays an important role in cell proliferation and cytoskeletal remodeling. In fibroblasts, SLK has been shown to respond to FAK/Src signaling and regulate focal adhesion turnover through Paxillin phosphorylation. Full-length SLK has also been shown to be essential for embryonic development. In myoblasts, the overexpression of a dominant negative SLK is sufficient to block myoblast fusion. Methods In this study, we crossed the Myf5-Cre mouse model with our conditional SLK knockout model to delete SLK in skeletal muscle. A thorough analysis of skeletal muscle tissue was undertaken in order to identify defects in muscle development caused by the lack of SLK. Isometric force analysis was performed on adult knockout mice and compared to age-matched wild-type mice. Furthermore, cardiotoxin injections were performed followed by immunohistochemistry for myogenic markers to assess the efficiency muscle regeneration following SLK deletion. Results We show here that early deletion of SLK from the myogenic lineage does not markedly impair skeletal muscle development but delays the regenerative process. Interestingly, adult mice (~6 months) display an increase in the proportion of central nuclei and increased p38 activation. Furthermore, mice as young as 3 months old present with decreased force generation, suggesting that the loss of SLK impairs myofiber stability and function. Assessment of structural components revealed aberrant localization of focal adhesion proteins, such as FAK and paxillin. Our data show that the loss of SLK results in unstable myofibers resulting in a progressive myopathy. Additionally, the loss of SLK resulted in a delay in muscle regeneration following cardiotoxin injections. Conclusions Our results show that SLK is dispensable for muscle development and regeneration but is required for myofiber stability and optimal force generation

Biomass Mediated Synthesis of ZnO and ZnO/GO for the Decolorization of Methylene Blue under Visible Light Source

: In this study, zinc oxide (ZnO) as well as ZnO/GO (zinc oxide/graphene oxide) were successfully synthesized. The Carica papaya leaf extract was used to synthesize ZnO and oil palm empty fruit bunch biomass to obtain graphene, which was further used to obtain graphene oxide. The samples were characterized through a variety of analytical methods such as scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy and UV–Visible spectroscopy in order to understand their morphology, size, structural phase purity, functional groups and optical properties. Various peaks such as O-H, Zn-OH and Zn-O were found in the case of ZnO. Some additional peaks, such as C-C and C=C, were also been detected while analyzing the sample by Fourier-transform infrared spectroscopy. The results of the XRD and SEM studies demonstrated that the synthesized material shows the crystalline nature of the substance in the case of ZnO, and the crystallinity decreases for ZnO/GO. The average crystallite size was found to 80.0 nm for ZnO and 74.0 nm for ZnO/GO. Further, a red shift was shown in the case of ZnO/GO, which was indicated by the UV–Vis absorption spectrum. In the TEM analysis, the particles were shown to be nanosized. For instance, the highest number of particles was found in the range of 100 to 120 nm in the case of ZnO, while 80–100 nm sized particles were found for ZnO/GO. Using synthesized ZnO and ZnO/GO, the decolorization of methylene blue was found to be 64% and 91%, respectively

Optomechanical damping of a microcantilever force sensor in liquid

A new instrument, constant deflection atomic force microscopy (CD-AFM) constructed to perform force spectroscopy measurements without mechanical instabilities associated with the use of soft AFM cantilevers has been developed, tested and calibrated. One of the major limitations associated with the use of soft AFM cantilevers in force spectroscopy measurements is cantilever mechanical instabilities. This includes thermodynamic noise and the cantilever non-equilibrium deflection close to the surface. This limitation can obscure ultrahigh force resolution and short range force measurements, and limits the accessible dynamic range. More stable stiff cantilevers have poor force resolution. The force resolution of the softest standard cantilever limited by thermodynamic noise has been improved from approximately 30 pN to ~2 pN using the CD-AFM system. It was proved that the discontinuity in the force distance curve close to the surface, approximately 7 nm, was prevented using CD-AFM. The cantilever deflection is kept constant even after the cantilever jumps to the surface. Using CD-AFM, inaccessible regions near the surface can be explored and valuable information about very short tip-surface interactions can be studied. The need to lock cantilever deflection prevents the use of the deflection signal to record tip-surface interactions. Alternatively, the laser signal used to keep the cantilever deflection constant is employed to record the interactions. The curves obtained using CD-AFM were scaled in force using a new method introduced for this purpose. The new calibration method was tested, and validated through electrostatic force measurements, with curves obtained using conventional AFM or CD-AFM showing the same behavior. Application of CD-AFM to unfold a five concatamer of the protein immunoglobulin 27 showed that CD-AFM has a wider dynamic range than conventional AFM. For example, loading rate in conventional AFM is limited by the cantilever stiffness and the pulling speed. Using CD-AFM the loading rate increases but without degenerating the force resolution. Moreover, protein L shows no refolding event using conventional AFM due to the tension loaded on the refolded protein by cantilever recoil. Using CD-AFM the cantilever recoil was removed and the refolding events become observable