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In this article, we propose a novel alternating minimization scheme for finding completely positive factorizations. In each iteration, our method splits the original factorization problem into two optimization subproblems, the first one being a orthogonal procrustes problem, which is taken over the orthogoal group, and the second one over the set of entrywise positive matrices. We present both a convergence analysis of the method and favorable numerical results. [ABSTRACT FROM AUTHOR]

The circumcentered-reflection method (CRM) has been recently proposed as a methodology for accelerating several algorithms for solving the Convex Feasibility Problem (CFP), equivalent to finding a common fixed-point of the orthogonal projections onto a finite number of closed and convex sets. In this paper, we apply CRM to the more general Fixed Point Problem (denoted as FPP), consisting of finding a common fixed-point of operators belonging to a larger family of operators, namely firmly nonexpansive operators. We prove that, in this setting, CRM is globally convergent to a common fixed-point (supposing at least one exists). We also establish the linear convergence of the sequence generated by CRM applied to FPP under a not too demanding error bound assumption, and provide an estimate of the asymptotic constant. We provide solid numerical evidence of the superiority of CRM when compared to the classical Parallel Projections Method (PPM). Additionally, we present certain results of convex combination of orthogonal projections, of some interest on its own. [ABSTRACT FROM AUTHOR]

In this paper, we first derive a characterization of the solution set of a continuously differentiable system of equations subject to a closed feasible set. Assuming that a constrained local error bound condition is satisfied, we prove that the solution set can locally be written as the intersection of a differentiable manifold with the feasible set. Based on the derivation of this result, we then show that the projected Levenberg–Marquardt method converges locally R-linearly to a possibly nonisolated solution under significantly weaker conditions than previously done. [ABSTRACT FROM AUTHOR]

Lignin, a renewable polymer derived from the lignocellulosic biomass represents more than 20% of the total mass of the Earth's biosphere. However, 98% of lignin is burned as a source of energy in the pulp and paper industry, essentially due to its complex structure. Today, the valorization of lignin into the production of value-added chemicals represents a real challenge in terms of both sustainability and environmental protection. The present contribution aims to provide a critical discussion on the crucial choice of the starting material to study lignin valorization. Next, a comparison between the different oxidation routes investigated by chemists over the past several years is presented, with emphasis on the major difficulties encountered. The main current challenges regarding the heterogeneous catalytic oxidation of lignin and its derivatives are also highlighted. Particular focus is given to innovative strategies favoring mild reaction conditions. Finally, we provide some recommendations and routes worthy of interest in this studied area of research in order to generate value-added chemicals from lignin oxidation through the use of heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

In Southern Kyrgyzstan, large landslides frequently occur with a high potential for endangering human lives and infrastructure. Landslides are especially concentrated along the eastern rim of the Fergana basin, which represents an important human living space in this mountainous country. The relationships between landslide occurrence and predisposing and triggering factors have not been completely understood yet. An objective and comprehensive landslide inventory is a prerequisite for these analyses. The paper shows how the use of multi-temporal remote sensing data combined with landslide information from other sources allows to create a multi-temporal landslide inventory for the data-scarce study area in Southern Kyrgyzstan. The application of GIS methods enables an efficient data integration and access as well as automated derivation of landslide attributes. [ABSTRACT FROM AUTHOR]

TRIUMF’s neutral atom trap for β decay (TRINAT) has been used to measure the most accurate β- ν correlation. Plans include improving that measurement, and also carrying out a full program of spin-polarized β decay correlation measurements complementary to the decay of the neutron [ABSTRACT FROM AUTHOR]

The β+ decay of 21Na to 21Ne is one of the four cases currently being used to determine the value of Vud from nuclear mirror (T=1/2) transitions. To date, published values for the half-life of 21Na have not been consistent with one another. We report here a new measurement of the half-life: 22.4615±0.0039(stat)±0.00010.0015(syst)s. This result increases the world average of the 21Na half-life by 0.0048 s and reduces the uncertainty by a factor of 1.5. [ABSTRACT FROM AUTHOR]

Review: 105 refs. [ABSTRACT FROM AUTHOR]

Using Triumf's neutral atom trap, Trinat, for nuclear β decay, we have measured the β asymmetry with respect to the initial nuclear spin in 37K to be Aβ=-0.5707(13)syst(13)stat(5)pol, a 0.3% measurement. This is the best relative accuracy of any β-asymmetry measurement in a nucleus or the neutron, and is in agreement with the standard model prediction -0.5706(7). We compare constraints on physics beyond the standard model with other β-decay measurements, and improve the value of Vud measured in this mirror nucleus by a factor of 4. [ABSTRACT FROM AUTHOR]

Iran has experienced a drastic increase in water scarcity in the last decades. The main driver has been the substantial unsustainable water consumption of the agricultural sector. This study quantifies the spatiotemporal dynamics of Iran's hydrometeorological water availability, land cover, and vegetation growth and evaluates their interrelations with a special focus on agricultural vegetation developments. It analyzes globally available reanalysis climate data and satellite time series data and products, allowing a country-wide investigation of recent 20+ years at detailed spatial and temporal scales. The results reveal a wide-spread agricultural expansion (27,000 km[Formula: see text]) and a significant cultivation intensification (48,000 km[Formula: see text]). At the same time, we observe a substantial decline in total water storage that is not represented by a decrease of meteorological water input, confirming an unsustainable use of groundwater mainly for agricultural irrigation. As consequence of water scarcity, we identify agricultural areas with a loss or reduction of vegetation growth (10,000 km[Formula: see text]), especially in irrigated agricultural areas under (hyper-)arid conditions. In Iran's natural biomes, the results show declining trends in vegetation growth and land cover degradation from sparse vegetation to barren land in 40,000 km[Formula: see text], mainly along the western plains and foothills of the Zagros Mountains, and at the same time wide-spread greening trends, particularly in regions of higher altitudes. Overall, the findings provide detailed insights in vegetation-related causes and consequences of Iran's anthropogenic drought and can support sustainable management plans for Iran or other semi-arid regions worldwide, often facing similar conditions., (© 2022. The Author(s).)

Why took it nearly four decades, from the first evidence of artificial creation of bremsstrahlung, noted indirectly in literature in 1857 by Julius Pluecker, Professor of mathematics and physics in Bonn, Germany, to Professor Conrad Wilhelm Roentgen's breaking discovery and announcement of X-rays in 1895? Following introductory remarks on the difficulties adjusting the parameters required to generate X-rays and the way medical X-rays occupied clinical routine after Roentgen's revolutionary discovery, and answering the question at the beginning, this paper will discuss in depth the paths taken for improvement up to the present, and some of the culs-de-sac., (Copyright © 2020 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Using Triumf's neutral atom trap, Trinat, for nuclear β decay, we have measured the β asymmetry with respect to the initial nuclear spin in ^{37}K to be A_{β}=-0.5707(13)_{syst}(13)_{stat}(5)_{pol}, a 0.3% measurement. This is the best relative accuracy of any β-asymmetry measurement in a nucleus or the neutron, and is in agreement with the standard model prediction -0.5706(7). We compare constraints on physics beyond the standard model with other β-decay measurements, and improve the value of V_{ud} measured in this mirror nucleus by a factor of 4.

The heterogeneous oxidation of vanillyl alcohol to vanillin was investigated on new grounds under eco-friendly conditions in the presence of hydrogen peroxide as an oxidant and water as solvent, coupled with low frequency ultrasonic irradiation. The sono-Fenton-like-assisted vanillyl alcohol oxidation was performed with a high-surface area nanostructured spinel cobalt oxide catalyst exhibiting small crystallites size. The catalytic reaction was also carried out under conventional heating conditions for comparison purposes. The influence of the reaction parameters, namely catalyst loading and hydrogen peroxide concentration was studied with the aim of determining the optimum yield and selectivity to the desired vanillin product. The chemical effects of ultrasound (ability to generate hydroxyl radicals) along with increased mass transfer appeared to be key prerequisites for enhancing the efficiency of the process, while decreasing the overall energy consumption., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Lignocellulosic biomass represents a natural renewable chemical feedstock that can be used to produce high value-added chemicals and platform molecules. Nowadays, there are extensive studies on a variety of aspects concerning the valorization of lignocellulosic biomass into desirable products. Among the current technologies for biomass conversion some require extreme conditions along with high temperatures and pressures. Therefore, major technological innovations based on more economical and environmental methodologies are currently developed both in academic laboratories and in industry. In this context, ultrasound-assisted catalysis constitutes an alternative method offering new strategies to upgrade biomass. The possibility of combining catalysis with sonication indeed provides avenues that are worth exploring for the valorization of lignocellulosic compounds into value-added chemical feedstocks. In this mini-review, the available sonochemical systems are first presented, with a focus on the most important ultrasonic parameters, which is intended to provide a mechanistic background. Next, this contribution aims to provide insight into the most recent developments along with prominent examples in the field of sonocatalysis applied to the chemical transformation of lignocellulosic biomass and its derivatives.

The analysis of hyperspectral images is an important task in Remote Sensing. Foregoing radiometric calibration results in the assignment of incident electromagnetic radiation to digital numbers and reduces the striping caused by slightly different responses of the pixel detectors. However, due to uncertainties in the calibration some striping remains. This publication presents a new reduction framework that efficiently reduces linear and nonlinear miscalibrations by an image-driven, radiometric recalibration and rescaling. The proposed framework-Reduction Of Miscalibration Effects (ROME)-considering spectral and spatial probability distributions, is constrained by specific minimisation and maximisation principles and incorporates image processing techniques such as Minkowski metrics and convolution. To objectively evaluate the performance of the new approach, the technique was applied to a variety of commonly used image examples and to one simulated and miscalibrated EnMAP (Environmental Mapping and Analysis Program) scene. Other examples consist of miscalibrated AISA/Eagle VNIR (Visible and Near Infrared) and Hawk SWIR (Short Wave Infrared) scenes of rural areas of the region Fichtwald in Germany and Hyperion scenes of the Jalal-Abad district in Southern Kyrgyzstan. Recovery rates of approximately 97% for linear and approximately 94% for nonlinear miscalibrated data were achieved, clearly demonstrating the benefits of the new approach and its potential for broad applicability to miscalibrated pushbroom sensor data.

The effect of the timing of treatment with the ATP-regulated potassium channel agonist BMS-180448 was evaluated in isolated rat heart and ferret models of ischemia and reperfusion. In rat hearts, 10 microM BMS-180448, given before and after global ischemia as well as only during reflow, improved reperfusion contractile function and attenuated lactic dehydrogenase release, although reperfusion-only treatment was less effective. Cromakalim (10 microM) and bimakalim (10 microM) treatment before and after global ischemia afforded a degree of protection similar to that of BMS-180448, although they were not cardioprotective when given only during reperfusion. Pre- and post-treatment cardioprotection were abolished by glyburide. Ischemia/reperfusion significantly increased cytosolic calcium concentration ([Ca++]i) and BMS-180448 given only during reperfusion attenuated this change. In anesthetized ferrets, BMS-180448 (2 mg/kg) or vehicle was infused i.v. during a 40-min interval beginning 1) 10 min before coronary occlusion, 2) at the 45th min of ischemia or 3) at the 5th min of reperfusion. Preocclusion administration of BMS-180448 was associated with a 35% reduction in infarct damage from that recorded in vehicle-treated control ferrets. Drug administered at the midpoint of ischemia reduced infarct size approximately 44%, whereas delaying BMS-180448 infusion until the 5th min of reperfusion reduced, but still provided a significant (17%) level of salvage. The favorable effects of BMS-180448 in the ferret were not associated with changes in either collateral blood flow or peripheral hemodynamics. Thus BMS-180448 shows some protective effects when given only during reperfusion. Cromakalim and bimakalim did not exert similar actions and the difference may be secondary to the faster penetration of BMS-180448.

Adenosine triphosphate (ATP)-sensitive potassium channel openers as a class exert cardioprotective effects, and we can separate vasodilator from glyburide-reversible cardioprotective activity in cromakalim analogs (e.g., BMS-180448). The purpose of this study was to determine the relation between cardiac function, energy status, and cardioprotective effects for BMS-180448 in isolated rat hearts compared with diltiazem. BMS-180448 (1-30 microM) or 0.1-1 microM diltiazem were given 10 min before 25-min global ischemia in rat hearts followed by 30 min of reperfusion. Both compounds significantly increased time to the onset of contracture during ischemia and improved postischemic recovery of contractile function in a concentration-dependent manner. At equivalent cardioprotective concentrations, BMS-180448 depressed preischemic cardiac function significantly less than did diltiazem. During ischemia, diltiazem significantly accelerated the functional decline observed in vehicle-treated hearts, whereas BMS-180448 attenuated the net rate of decline of function. Despite these different effects on preischemic and ischemic cardiac function, diltiazem and BMS-180448 conserved cardiac ATP during ischemia to a similar degree. BMS-180448 enhanced the recovery of ATP (also seen for diltiazem, but not to the same magnitude) and creatine phosphate during reperfusion compared with vehicle-treated hearts. For BMS-180448, this enhanced ATP recovery was accompanied by a significant improvement in the efficiency of oxygen use, which was profoundly reduced in reperfused vehicle-treated hearts. BMS-180448 also significantly enhanced the functional reserve after the 25-min period of global ischemia. Thus BMS-180448 protects ischemic myocardium and conserves ATP with less reduction in cardiac function compared with diltiazem.

There is ample evidence that potassium channel openers protect the ischaemic myocardium. Although the protective mechanism is unknown, indirect evidence suggests that potassium channel openers reduce calcium influx during ischaemia which may explain their protective effects. However, recently discovered potassium channel openers such as BMS-180448 are cardioprotective without displaying classical indications of calcium lowering. The current study was designed to provide direct evidence that potassium channel openers delay or prevent increased intracellular free calcium in the myocardium during ischaemia and reperfusion. Cytosolic calcium concentrations were directly measured in perfused rat hearts during global ischaemia by 19F-NMR of the calcium chelator 5F-BAPTA. The cytosolic Ca2+ concentration in vehicle-treated hearts increased from a pre-ischaemia average of 310 +/- 40 nM to 1000 +/- 130 nM during 25 min of ischaemia, followed by partial recovery to 530 +/- 100 nM during 19 min of reperfusion. In contrast, the cytosolic Ca2+ concentration in hearts treated with potassium channel openers BMS-180448 and cromakalim remained low throughout ischaemia, changing from pre-ischaemia averages of 270 +/- 30 nM to 230 +/- 60 nM and from 240 +/- 20 nM to 170 +/- 30 nM during 25 min of ischaemia, respectively. The cytosolic Ca2+ concentrations in these hearts increased to 440 +/- 110 nM in BMS-180448 treated hearts and 290 +/- 60 nM in cromakalim treated hearts during the first 6 min of reperfusion, and were 460 +/- 60 nM for BMS-180448 and 600 +/- 70 nM for after cromakalim 19 min of reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral inoculation of lactose utilizing cecal bacteria plus 2.5% lactose treatments were tested in young chicks for protective efficacy against infection by Salmonella enteritidis. One-day-old chicks were treated with cecal bacteria upon arrival and challenged orally on day 3 with 10(4)-10(6) cfu S. enteritidis. A single culture identified as Escherichia coli O75:H10 was found significantly more protective than all other isolates tested. This isolate excreted a metabolite(s) in vitro that was inhibitory towards the growth of S. enteritidis. The results of this study indicate that discovery of protective strains can be facilitated by screening isolates in vitro for lactose utilization and growth inhibition of S. enteritidis before administration of treatment.

NMR data that underscore the importance of the membrane in ligand-receptor interactions were obtained and analyzed. The following hypothesis for acetylcholine (ACh) binding to the acetylcholine receptor (AChR) is proposed: ACh first binds to the membrane, where it adopts its bioactive conformation, and it then rapidly diffuses along the membrane to bind to the AChR in its already-correct conformation. Data used to support this hypothesis include (a) the NMR-determined binding constant of KM = (2.8 +/- 0.6) x 10(3) M-1 for the binding of ACh to the asolectin membrane, (b) the lipid dependence of AChR activity, (c) the location of the ACh binding site close to the membrane surface, and (d) the conformation of ACh in its membrane-bound state. Additional experiments to test this hypothesis are proposed.

NMR microscopy was used to obtain transverse flow profiles of arterial blood flow in the rat carotid artery at 33 microns resolution. The images were gated to the EKG and correspond to identified regions of diastole. The profiles show that flow is laminar during this part of the heart cycle. These results provide the first direct view of blood flow profiles in arteries of submillimeter diameter and suggest that animals as small as juvenile rodents will serve as valuable models for hemodynamic studies. Extensions to flow during systole, stenoses, and flow in the vicinity of the carotid bifurcation are discussed.