Excellent Conservation Research Articles

QUALITY OF MINIMALLY PROCESSED ‘FUJI’ APPLE UNDER REFRIGERATED STORAGE AND TREATMENT WITH ADDITIVES

ABSTRACT The aim of this study was to evaluate the ability to prolong the useful life of the minimally processed ‘Fuji’ apple by applying the individual or combined additives (L-cysteine chloride, L-ascorbic acid and calcium chloride) and to determine the appropriate period of storage of the whole fruit to perform the minimum processing. The experimental design was completely randomized in three-factor design with three replications. Factor A was composed of storage periods of whole apples, pre-processing, in cold chambers (20, 78, 138 and 188 days); the factor B was represented by storage periods minimum post-processing, simulating shelf life (3, 6, 9 and 12 days), and factor C was represented by chemical additives (distilled water, as control, 0.5% L-cysteine chloride, 1% L-ascorbic acid, 0.5% L-cysteine chloride along with 1% calcium chloride and 1% L-ascorbic acid together with 1% calcium chloride). The evaluated dependent variables were pulp color (L* and hº), soluble solids, titratable acidity, content of phenolic compounds, antioxidant capacity and quantification of polyphenol oxidase. In addition, was analyzed the presence or absence of Salmonella sp. and Escherichia coli. The prolongation of the storage time of ‘Fuji’ apples in a refrigerated atmosphere promotes increased susceptibility to browning and softening after processing from 78 days of storage. The use of additives in the process, helps prevent these problems, especially when combined 0.5% L-cysteine chloride with 1% calcium chloride, achieving an excellent conservation in refrigerated shelf up to 6 days. From a microbiological aspect, minimally processed apples are toxicologically safe.

MultiSymplectic Discretization of Wave Map Equations

We present a new multi-symplectic formulation of constrained Hamiltonian partial differential equations, and we study the associated local conservation laws. A multi-symplectic discretisation based on this new formulation is exemplified by means of the Euler box scheme. When applied to the wave map equation, this numerical scheme is explicit, preserves the constraint and can be seen as a generalisation of the Shake algorithm for constrained mechanical systems. Furthermore, numerical experiments show excellent conservation properties of the numerical solutions.

Eudontomyzon danfordi (Regan, 1911) Species Populations Ecological Status in Maramureş Mountains Nature Park (Romania)

Abstract The Eudontomyzon danfordi characteristic habitats state of Maramureş Mountains Nature Park varies greatly, 19.05% are in excellent conservation status, 47.62% are in good/average status and 33.33% are in a partially degraded condition. The identified human impact categories which induced the decreasing of Eudontomyzon danfordi species habitat state in the studied area are: poaching, minor riverbeds morphodynamic changings, liquid and solid natural flow disruption, destruction of riparian trees and bush vegetation, habitat fragmentation-fish populations isolation, and organic/mining pollution activities.

An enhanced version of the heat exchange algorithm with excellent energy conservation properties.

We propose a new algorithm for non-equilibrium molecular dynamics simulations of thermal gradients. The algorithm is an extension of the heat exchange algorithm developed by Hafskjold et al. [Mol. Phys. 80, 1389 (1993); 81, 251 (1994)], in which a certain amount of heat is added to one region and removed from another by rescaling velocities appropriately. Since the amount of added and removed heat is the same and the dynamics between velocity rescaling steps is Hamiltonian, the heat exchange algorithm is expected to conserve the energy. However, it has been reported previously that the original version of the heat exchange algorithm exhibits a pronounced drift in the total energy, the exact cause of which remained hitherto unclear. Here, we show that the energy drift is due to the truncation error arising from the operator splitting and suggest an additional coordinate integration step as a remedy. The new algorithm retains all the advantages of the original one whilst exhibiting excellent energy conservation as illustrated for a Lennard-Jones liquid and SPC/E water.

Experimental determination of the steady-state charging probabilities and particle size conservation in non-radioactive and radioactive bipolar aerosol chargers in the size range of 5-40nm.

Three bipolar aerosol chargers, an AC-corona (Electrical Ionizer 1090, MSP Corp.), a soft X-ray (Advanced Aerosol Neutralizer 3087, TSI Inc.), and an α-radiation-based 241Am charger (tapcon & analysesysteme), were investigated on their charging performance of airborne nanoparticles. The charging probabilities for negatively and positively charged particles and the particle size conservation were measured in the diameter range of 5–40 nm using sucrose nanoparticles. Chargers were operated under various flow conditions in the range of 0.6–5.0 liters per minute. For particular experimental conditions, some deviations from the chosen theoretical model were found for all chargers. For very small particle sizes, the AC-corona charger showed particle losses at low flow rates and did not reach steady-state charge equilibrium at high flow rates. However, for all chargers, operating conditions were identified where the bipolar charge equilibrium was achieved. Practically, excellent particle size conservation was found for all three chargers.Electronic supplementary materialThe online version of this article (doi:10.1007/s11051-015-2981-x) contains supplementary material, which is available to authorized users.

Diversity and richness of small mammals at a well-conserved site of The Yungas in Jujuy Province, Argentina

AbstractWe present the results obtained from 12 small-mammal surveys conducted between 1996 and 2013 in “Finca Las Capillas”, province of Jujuy, Argentina. This region has been formally recognized as an “Area of Importance for the Conservation of Bats” (AICOM) based on the diversity of species detected in our previous studies. This site in the Yungas forests of northwestern Argentina still maintains an excellent conservation status due to restrictions to human activities involving deforestation and limitations to cattle-raising imposed 50 years ago. A total of 39 species belonging to three orders, namely, Didelphimorphia, Chiroptera and Rodentia, were recorded. The species accumulation curve revealed that our records represent 83–95% of the community, and with high diversity indexes. Several of the genera and species that we recorded from our collection trips have been included in the fauna of Argentina. Our previous studies and the present findings provide new records for the province or significant extensions to previously known distributions of several taxa of small mammals. These results show that the site represents an icon for conservation in such a fragmented and exploited area as the Yungas in Argentina today.

Study on optimized principles of process parameters for environmentally friendly machining austenitic stainless steel with high efficiency and little energy consumption

Green manufacturing is one of the important development directions for advanced manufacturing technology. In this paper, the orthogonal turning experiment of multiple factors with the minimal quantity lubrication (MQL), dry machining, and wet machining is designed to contrast the machinability for austenitic stainless steel in order to realize environmentally friendly machining with high efficiency, excellent surface quality, energy conservation, and little consumption for austenitic stainless steel. On the basis of the experiment results, in which the conditions of MQL or dry machining instead of wet machining are given, the optimized principle of process parameters for high surface quality and environmentally friendly machining austenitic stainless steel with high machining efficiency and little energy consumption is found and proposed by the comprehensive evaluation of the integrated mechanism of the process parameters with relative cutting-specific energy, unit cutting force, surface roughness, and process condition of MQL and dry machining. The research conclusions have theoretical and practical importance for production and process to give the relevant optimized principle of process parameters for machined hardening stainless steels by studying the integrated mechanism of the process parameters especially on the basis of the orthogonal experiment of multiple factors with little experiment consumption and cost.

Decadal den fidelity of a highly mobile reef lobster

Palinurid (spiny) lobsters are a group of highly mobile decapod crustaceans (Childress and Jury 2006). An understanding of lobster behaviour and habitat use is valuable for fisheries management and conservation, especially since palinurids are among the world’s most sought-after seafood. The painted spiny lobster (Panulirus versicolor) exclusively inhabits coral reefs of the Indian and Pacific Oceans, including the Great Barrier Reef (GBR; Australia). Although some lobster species show fidelity to small reef areas, none are known to remain in the same place for periods up to a decade (Childress and Jury 2006). Here we report an observation of long-term (decadal) site fidelity of P. versicolor from Northwest Island (23°18’S, 151°43’E) in the GBR. On 3 May 2013, we captured a male P. versicolor (144 mm carapace length) that was initially captured on 28 December 2003 (114 mm carapace length). Identity was confirmed via elastomer implant and unique body markings (Fig. 1). Initial capture and final capture occurred at the same coral shelter or den (confirmed by GPS), although it was known occasionally to use other nearby dens (within 200 m). It shared a den with a small (two to three) harem of females, which changed through time. Despite being periodically harassed (i.e. captured and handled on at least five occasions between 2004 and 2006) and occasionally injured (i.e. limb loss due to autotomy), this individual maintained a long-term association with a particular den. Previous work has shown that individual spiny lobsters, including those of Jasus edwardsii and P. versicolor, are capable of moving 0.5–6 km (Kelly and MacDiarmid 2003; Frisch 2007). A high degree of site fidelity in marine species is often associated with a tendency towards over-exploitation and/or vulnerability to extinction (Cheung et al. 2007). Given the importance of the den for protection against potential predators and for providing mating opportunities, it is likely that protection of high quality dens (in marine reserves, for example) may provide excellent conservation outcomes for this species.

Plasmodium falciparum Hop: Detailed analysis on complex formation with Hsp70 and Hsp90

The heat shock organizing protein (Hop) is important in modulating the activity and co-interaction of two chaperones: heat shock protein 70 and 90 (Hsp70 and Hsp90). Recent research suggested that Plasmodium falciparum Hop (PfHop), PfHsp70 and PfHsp90 form a complex in the trophozoite infective stage. However, there has been little computational research on the malarial Hop protein in complex with other malarial Hsps. Using in silico characterization of the protein, this work showed that individual domains of Hop are evolving at different rates within the protein. Differences between human Hop (HsHop) and PfHop were identified by motif analysis. Homology modeling of PfHop and HsHop in complex with their own cytosolic Hsp90 and Hsp70 C-terminal peptide partners indicated excellent conservation of the Hop concave TPR sites bound to the C-terminal motifs of partner proteins. Further, we analyzed additional binding sites between Hop and Hsp90, and showed, for the first time, that they are distinctly less conserved between human and malaria parasite. These sites are located on the convex surface of Hop TPR2, and involved in interactions with the Hsp90 middle domain. Since the convex sites are less conserved than the concave sites, it makes their potential for malarial inhibitor design extremely attractive (as opposed to the concave sites which have been the focus of previous efforts).

A meshfree interface-finite element method for modelling isothermal solutal melting and solidification in binary systems

In this paper, numerical modelling of isothermal solutal melting and solidification in binary systems is done using a new meshfree interface-finite element method (MI-FEM) where the implicitly represented liquid–solid interface is allowed to arbitrarily intersect the finite elements. A meshfree radial basis functions (RBFs) method is used for solving a distance-regularized level set (DRLS) equation such that re-initialization is completely eliminated and fast marching algorithms for interfacial velocity extension are not necessary resulting in a more efficient solution with excellent volume conservation. In the proposed method, intersection points between the mesh and the zero level set are used as meshfree nodes such that at the interface-embedded elements interpolants are constructed using meshfree RBFs ensuring both the partition of unity and Kronecker-delta properties are satisfied allowing for precise and easy imposition of Dirichlet boundary conditions (DBCs) on each side of the interface. A coupling of the MI-FEM with a new meshfree automata (MA) method is used to efficiently predict the microstructural evolution during solidification. Benchmark problems with strong discontinuities were solved where very good accuracy was obtained. The solute conservation and interfacial equilibrium equations describing solutal phase transformation in binary systems were solved using the newly developed method. Mathematical formulation and implementation followed by numerical results and analysis will be presented and discussed.

Fast Ion Trajectory Calculations in Tokamak Magnetic Configuration Using Symplectic Integration Algorithm

A numerical scheme based on Symplectic Integration Algorithm (SIA) has been used to develop an orbit following code to calculate fast ion trajectories in tokamak magnetic configuration. For the purpose of demonstrating the expediency of symplectic schemes, the algorithm has been applied to the H´enon-Heiles system and compared with non- symplectic Runge–Kutta Algorithm (RKA) for numerically integrating the Hamiltonian equations. In contrast to RKA, the long-time stability of SIA has been highlighted. Furthermore, the SIA has been used to find the exact trajectories of, trapped and passing, fast ions in tokamak. In particular, the effect of an intrinsic magnetic field perturbation has been investigated, i.e. toroidal field ripples. This perturbation is toroidal field ripple (TFR) which are there due the discrete number to toroidal coils around the torus. The numerical scheme used shows excellent conservation of particle energy as well as of angular momentum (in axi-symmetric case). The effect of TFR on these trajectories has been simulated and it is shown that the resonance between toroidal precession of bananas and the field ripples results in spread of the trajectories for banana particles, whereas the passing fast ions are unaffected.

A 3D front-tracking approach for simulation of a two-phase fluid with insoluble surfactant

Surface active agents play a significant role in interfacial dynamics of multiphase systems.While the understanding of their behavior is crucial to many important practical applications, realistic mathematical modeling and computer simulation represent an extraordinary task. By employing a front-tracking method with Eulerian adaptive mesh refinement capabilities in concert with a finite volume scheme for solving an advection–diffusion equation constrained to a moving and deforming interface, the numerical challenges posed by the full three-dimensional computer simulation of transient, incompressible two-phase flows with an insoluble surfactant are efficiently and accurately tackled in the present work. The individual numerical components forming the resulting methodology are here combined and applied for the first time. Verification tests to check the accuracy and the simulation of the deformation of a droplet in simple shear flow in the presence of an insoluble surfactant are performed, the results being compared to laboratory experiments as well as to other numerical data. In all the cases considered, the methodology presents excellent conservation properties for the total surfactant mass (even to machine precision under certain circumstances).

Abstract 1226: Breast and ovarian cancer PDXs show excellent conservation of original features but are genetically plastic

Abstract Patient derived xenografts (PDXs) are increasingly appreciated models in cancer research and preclinical testing. We have established a collection of 20 breast and 20 ovarian cancer PDXs and investigated their biological and clinical characteristics, as well as their genetic stability. Take rates were distinctly lower with breast (16%) compared to ovarian cancers (85%). The majority of our breast PDX originated from triple negative (14/20), grade 3 tumors (18/20) and breast cancers with reduced recurrence free survival. Interestingly, we stabilized 1 ER-/HER2+ and 5 ER+ PDX. Overall we showed that breast tumors that gave rise to a PDX (take) showed significantly different expression profiles compared to tumors which did not take. Ovarian PDX originated all from high grade cancers, but comprised all major ovarian cancer histotypes (mucinous, clear cell, carcinosarcoma and serous carcinoma). Breast and ovarian PDXs faithfully recapitulated the histological features of their tumors of origin. The excellent conservation of original transcriptome characteristics was a further proof of the phenotypic stability shown by our PDX models. Noticeably, all grafts from ER+ cancers expressed ER at the RNA and protein levels. Array-CGH analysis revealed that PDXs presented a high degree of conservation of the Copy Number Change (CNC) profiles of the tumors they stemmed from and profiles from PDXs established from the same original tumor were highly overlapping. We determined that CNC representing up to 6% of the genome corresponded to oligoclonal events present in the tumor of origin that got gradually lost in the PDXs along passages. Furthermore, we noted that a minority of the PDXs presented a fraction of de novo occurring events representing up to 10% of the genome, suggesting limited levels of ongoing genetic instability. In conclusion, our data show that breast and ovarian cancer PDX are excellent reproductions of the tumors of origin but remain genetically dynamic elements susceptible to drift during sequential passages. Citation Format: Charles G. Theillet, Stanislas du Manoir, Beatrice Orsetti. Breast and ovarian cancer PDXs show excellent conservation of original features but are genetically plastic. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1226. doi:10.1158/1538-7445.AM2014-1226

Rural Residential Wall Construction Technology Vitrified Microsphere Thermal Insulation System of Shanxi Luliang

The experimental studies have suggested that thermal insulation glazed hollow bead mortar is a splendid material with thermal insulation and energy conservation. The practices also prove that this material can produce excellent thermal conservation effect when it is applied to building with the request for thermal insulation and energy conservation. In light of the fact that the thermal insulation gazed hollow bead mortar hasn’t been spread in Luliang rural area, taking the actual environment in this area and the special method of the building’s construction into consideration, the construction technology of the thermal insulation gazed hollow bead mortar regarding the thermal insulation and energy conservation of the residential wall will be expounded.

Finite element implementation of an improved conservative level set method for two-phase flow

A novel improved conservative level set method is proposed to simulate two-phase flows in the finite element framework. The standard level set method can capture the interface smoothly and gives accurate normal vectors but suffers from an excessive amount of mass gain/loss. The conservative level set method exhibits excellent mass conservation properties but the results are usually contaminated by inaccurate interface normal vectors. To address this problem, an improved conservative level set method is proposed to capture the interface smoothly with excellent mass conservation properties. The improvement of the method lies in that the surface normal is computed from a signed distance function which is also advected and re-initialized in the flow fields instead of using the Heaviside function. The proposed method is implemented by an implicit two-step Taylor–Galerkin approximation together with the fractional step algorithm within the finite element context. The approach is validated with well-known benchmark problems, including the long term advection of a circle, rotation of a slotted disk, stretching of a circular, dam-break flow and the Rayleigh–Taylor instability problem. The results from the proposed method show good agreement with existing experimental and numerical published results and are found to be highly reliable and accurate.

A symmetry-preserving discretisation and regularisation model for compressible flow with application to turbulent channel flow

Most simulation methods for compressible flow attain numerical stability at the cost of swamping the fine turbulent flow structures by artificial dissipation. This article demonstrates that numerical stability can also be attained by preserving conservation laws at the discrete level. A new mathematical explanation of conservation in compressible flow reveals that many conservation properties of convection are due to the skew-symmetry of the convection operator. By preserving this skew-symmetry at the discrete level, a fourth-order accurate collocated symmetry-preserving discretisation with excellent conservation properties is obtained. Also a new symmetry-preserving regularisation subgrid-scale model is proposed. The proposed techniques are assessed in simulations of compressible turbulent channel flow. The symmetry-preserving discretisation for compressible flow has good stability without artificial dissipation and yields acceptable results already on coarse grids. Regularisation does not consistently improve upon no-model results, but often compares favourably with eddy-viscosity models.

Improved conservative level set method

SUMMARYThe standard level set (LS) method can capture the interface smoothly and gives accurate normal vectors but suffers from an excessive amount of mass gain/loss. The conservative LS method exhibits excellent mass conservation properties, but the result is usually contaminated by inaccurate interface normal vectors. To address this problem, the improved conservative LS method is proposed to capture the interface smoothly with excellent mass conservation properties. The improvement of the method lies in that the surface normal is computed from a signed distance function, which is also advected and reinitialized in the flow fields, instead of using the Heaviside function. The proposed method is implemented by implicit two‐step Taylor–Galerkin approximation within the finite element context. The approach is validated with the well‐known benchmark problems and is found out to be highly reliable and accurate. Copyright © 2014 John Wiley & Sons, Ltd.

Improved conservative level set method for free surface flow simulation

By coupling the standard and the conservative level set methods, an improved conservative level set method is proposed to capture the free surface smoothly with excellent mass conservation properties. The improvement lies in the fact that the surface normal is computed from a signed distance function instead of the Heaviside function. Comparing with the conservative level set method, the inevitable numerical discretization errors to point the surface normal in arbitrary directions could be eliminated, and the instability of the numerical solution could be improved efficiently. The advantage is clear in the straightforward combination of the standard level set and the conservative level set and a little effort is taken in coding compared with other coupled methods. The present method is validated with several well-known benchmark problems, including the 2-D Zalesak's disk rotating, the 3-D sphere stretching in deformation vortex and the dam break flow simulation. The results are shown to be in good agreement with the published experimental data and numerical results.

Breast tumor PDXs are genetically plastic and correspond to a subset of aggressive cancers prone to relapse

Patient derived xenografts (PDXs) are increasingly appreciated models in cancer research, particularly for preclinical testing, as they reflect the patient's tumor biology more accurately than cancer cell lines. We have established a collection of 20 breast PDXs and characterized their biological and clinical features, as well as their genetic stability. While most PDXs originated from triple negative breast cancers (70%), our collection comprised five ER + cases (25%). Remarkably, the tumors that produced PDXs derived from a subset of aggressive breast cancers with a high proportion of grade 3 tumors and reduced recurrence-free survival. Consistent with this, we found significant differences between the transcriptomic signatures of tumors that produced a PDX (Take) and those that did not (No Take). The PDXs faithfully recapitulate the histological features of their primary tumors, and retain an excellent conservation of molecular classification assignment and Copy Number Change (CNC). Furthermore, the CNC profiles of different PDXs established from the same tumor overlap significantly. However, a small fraction of CNCs in the primary tumor that correspond to oligoclonal events were gradually lost during sequential passaging, suggesting that the PDXs' genetic structure eventually stabilizes around a dominant clone present in the tumor of origin. Finally, de novo occurring genetic events covering up to 9% of the genome were found in only a minority of the PDXs, showing that PDXs have limited genetic instability. These data show that breast cancer PDXs represent a subset of aggressive tumors prone to relapse, and that despite of an excellent conservation of original features, they remain genetically dynamic elements.

Matrix-Based Ramanujan-Sums Transforms

In this letter, we study the Ramanujan Sums (RS) transform by means of matrix multiplication. The RS are orthogonal in nature and therefore offer excellent energy conservation capability. The 1-D and 2-D forward RS transforms are easy to calculate, but their inverse transforms are not defined in the literature for non-even function <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$ ({\rm mod}~ {\rm M}) $</tex></formula> . We solved this problem by using matrix multiplication in this letter.