Cloaking In-Plane Elastic Waves with Swiss Rolls

We propose a design of cylindrical cloak for coupled in-plane shear waves consisting of concentric layers of sub-wavelength resonant stress-free inclusions shaped as Swiss rolls. The scaling factor between inclusions’ sizes is according to Pendry’s transform. Unlike the hitherto known situations, the present geometric transform starts from a Willis medium and further assumes that displacement fields u in original medium and u ′ in transformed medium remain unaffected ( u ′ = u ). This breaks the minor symmetries of the rank-4 and rank-3 tensors in the Willis equation that describe the transformed effective medium. We achieve some cloaking for a shear polarized source at specific, resonant sub-wavelength, frequencies, when it is located in close proximity to a clamped obstacle surrounded by the structured cloak. The structured medium approximating the effective medium allows for strong Willis coupling, notwithstanding potential chiral elastic effects, and thus mitigates roles of Willis and Cosserat media in the achieved elastodynamic cloaking.

Revolutions and the Military: Endgame Coups, Instability, and Prospects for Democracy

This article presents a systematic analysis of military coups following popular mass uprisings in nondemocratic regimes, conceptualized as endgame coups. Drawing on our original, medium- n data set of revolutionary situations, we find that such endgame coups form a distinct type of military intervention in politics. Compared to regular coups, episodes of popular mass contestation prompt conservative interventions in politics of the military’s leadership aimed at preserving the regime’s authoritarian infrastructure. A systematic test of factors characterizing postcoup political trajectories is based on Cox proportional hazard models and provides empirical evidence in contrast to the widely held notion of “democratic coups.” Our findings reveal that endgame coups are conservative rollback coups, executed by military leaderships, that result in continued political instability and illiberal politics.

Improved Positive Predictive Performance of Listeria Indicator Broth: A Sensitive Environmental Screening Test to Identify Presumptively Positive Swab Samples

PDX-LIB, Listeria Indicator Broth, was developed as a proprietary sensitive screening test to identify presumptively positive environmental swab samples for Listeria sp. The original formulation, while sensitive, initially proved to exhibit acceptable levels of false positive test results. Paradigm Diagnostics has been undertaken to modify the medium formulation to render it more selective while not sacrificing its sensitivity. After identification of a candidate formulation through laboratory studies, a field trial was conducted to validate the test performance parameters, including the true positive frequency and false positive frequency in several different food-processing facilities. Identical swab samples were enriched in both the original medium formulation and the new formulation. Presumptive positive samples were confirmed by plating on selective differential agar and qPCR analysis. The field trial data demonstrate that the new formulation significantly reduces the frequency of false positive samples compared to the original Listeria Indicator Broth formulation, without compromising the sensitivity of the original formulation. The new medium formulation resulted in no false positive samples compared to the 54% increased presumptive positive samples obtained with the original medium formulation.

INFLUENCE OF CULTIVATION OF CHLORELLA VULGARIS ON MICROORGANISMS IN SEAFOOD WASTEWATER

Microalgae cultivation in wastewater for many purposes has been investigated recently decade ago. In this study, Chlorella vulgaris was chosen to culture for examination of its influences on microorganisms of seafood wastewater in particular aerobic bacteria, Coliform and E. coli. The microalgae cultivation was realized in Erlenmeyer flasks containing seafood wastewater medium. Another was also grown in original medium called Sueoka medium for control. All experiments were set up until almost all Chlorella vulgaris decanted or flocculated in the bottom of flasks. The changes of bacteria counts including aerobic bacteria, Coliform and E. coli were measured to evaluate the impact of cultivation of Chlorella vulgaris on them in this sewage. Otherwise, the growth of microalgae has been also recorded for evaluating the effect of a new medium on metabolism of Chlorella vulgaris. The results showed that the bacteria counts were significantly reduced after day 3 of microalgae culture. These results have been calculated the efficiency of aerobic bacteria, Coliform and E. coli elimination out of wastewater medium represented approximately 70%, 81% and 90% respectively. These eliminations provided evidences of difficult metabolism of bacteria under the presence of microalgae as like as Chlorella vulgaris. In other words, the symbiosis of microalgae and bacteria in sewage could prevent the raising of bacteria counts.

Study on Multi-Objective Reconstruction of Random Media

This paper deals with a reconstruction of random media via multi-objective optimization. Two statistical descriptors, namely a two-point probability function and a two-point lineal path function, are repetitively evaluated for the original medium and the reconstructed image to appreciate the improvement in the optimization progress. Because of doubts of the weights setting in the weighted-sum method, purely multi-objective optimization routine Non-dominated Sorting Genetic Algorithm~II is utilized. Three operators are compared for creating new offspring populations that satisfy a prescribed volume fraction constraint. The main contribution is in the testing of the proposed methodology on several benchmark images.

Cryopreservation of lumpfish Cyclopterus lumpus (Linnaeus, 1758) milt

This study has established a successful protocol to cryopreserve lumpfish Cyclopterus lumpus (Linnaeus, 1758) milt. Three cryosolutions were tested based on Mounib’s medium; the original medium including reduced l-glutathione (L-Glu), the basic sucrose and potassium bicarbonate medium without L-Glu, or with hen’s egg yolk (EY). Dimethyl sulphoxide (DMSO) was used as the cryoprotectant along with all three diluents in a 1 to 2 dilution. Cryopreservation was performed with the mentioned cryosolutions at two freezing rates. Motility percentages of spermatozoa were evaluated using ImageJ with a computer assisted sperm analyzer (CASA) plug-in. Findings revealed that spermatozoa cryopreserved in Mounib’s medium without L-Glu had a post-thaw motility score of 8.64 percentage points (pp) higher than to that with added L-Glu, and an addition of EY to the Mounib’s medium lowered the post-thaw motility score by 15.07 pp. The difference in motility between both freezing rates was 5.23 pp, and samples cryopreserved on a 4.8 cm high tray resulted in a better post-thaw motility score. Cryopreserved milt had a 23.76 pp lower post-thaw motility score when compared with fresh milt. Cryopreservation of lumpfish milt has, to our knowledge, never been successfully carried out before. The established protocol will be a main contributing factor in a stable production of lumpfish juveniles in future.

Cryopreservation of lumpfish Cyclopterus lumpus (Linnaeus, 1758) milt

This study has established a successful protocol to cryopreserve lumpfish Cyclopterus lumpus (Linnaeus, 1758) milt. Three cryosolutions were tested based on Mounib’s medium; the original medium including reduced l-glutathione (L-Glu), the basic sucrose and potassium bicarbonate medium without L-Glu, or with hen’s egg yolk (EY). Dimethyl sulphoxide (DMSO) was used as the cryoprotectant along with all three diluents in a 1 to 2 dilution. Cryopreservation was performed with the mentioned cryosolutions at two freezing rates. Motility percentages of spermatozoa were evaluated using ImageJ with a computer assisted sperm analyzer (CASA) plug-in. Findings revealed that spermatozoa cryopreserved in Mounib’s medium without L-Glu had a post-thaw motility score of 8.64 percentage points (pp) higher than to that with added L-Glu, and an addition of EY to the Mounib’s medium lowered the post-thaw motility score by 15.07 pp. The difference in motility between both freezing rates was 5.23 pp, and samples cryopreserved on a 4.8 cm high tray resulted in a better post-thaw motility score. Cryopreserved milt had a 23.76 pp lower post-thaw motility score when compared with fresh milt. Cryopreservation of lumpfish milt has, to our knowledge, never been successfully carried out before. The established protocol will be a main contributing factor in a stable production of lumpfish juveniles in future.

Optimization of the Components of Medium Producing Dextran from Immobilized Cells of Leuconostoc mesenteroides

The cells of Leuconostoc mesenteroides were immobilized for dextran producing and response surface methodology based on experimental designs were applied to optimize the medium for maximum yield. Eight different medium components were examined for their significance on dextran production using Plackett-Burman factorial design. Na2HPO4, CaCl2and sodium citrate were found to have significant effect on dextran production. The combined effect of these nutrients on dextran production was studied using central composite design. The optimal concentration of variables for maximum dextran production were 0.245 g/100mL of Na2HPO4, 0.05 g/100mL of CaCl2, 0.2084 g/100mL of sodium citrate. The maximum concentration of dextran obtained at 24 h by predicted model was 1.88045 mg/mL that was in perfect agreement with the experimental determined value 1.85395 mg/mL. Dextran yield was over 376% higher as compared to original medium which gave 0.38956 mg/mL of dextran.

A GENERALIZATION OF THE GINZBURG–LANDAU THEORY TO p-WAVE SUPERCONDUCTORS

We succeed in building up a straightforward theoretical model for spin-triplet p-wave superconductors, by introducing a second-order parameter and a nonlinear interaction between the two mean fields in the Ginzburg–Landau theory. Such interaction breaks the isotropy of the original medium and allows pairs of electrons to arrange into S = 1 Cooper pairs. The present model predicts a thermodynamical and magnetic behavior analogous to that observed in conventional s-wave superconductors.

A chemically defined medium for production of actinomycin D by Streptomyces parvulus

A chemically defined medium consisting of D(+)fructose, L(-)threonine, K2HPO4, MgSO4.7H2O, ZnSO4.7H2O, CaCl2.2H2O, FeSO4.7H2O and deionized water, was developed to maximize the synthesis of actinomycin D by the Streptomyces parvulus DAUFPE 3124 strain. This medium resulted in the maximum antibiotic concentration of 133mg/L while using the original medium the production of actinomycin D was poor not surpassing 43mg/L.