Dynamic Nanoindentation and Short-Range Order in Equiatomic NiCoCr Medium-Entropy Alloy Lead to Novel Density Wave Ordering.

Chemical short-range order is believed to be a key contributor to the exceptional properties of multicomponent alloys. However, its direct validation and confirmation has been highly elusive in most compounds. Recent studies for equiatomic NiCoCr alloys have shown that thermal treatments (i.e., annealing and aging) may facilitate and manipulate such ordering. In this work, by using molecular simulations, we show that nanomechanical probes, such as nanoindentation, may be utilized toward further manipulation of chemical short-range order, providing explicit validation pathways. By using well established interatomic potentials, we perform hybrid molecular-dynamics-Monte Carlo at room temperature to demonstrate that particular dwell nanoindentation protocols can lead, through thermal Monte Carlo equilibration, to local reorganization under the indenter tip, toward a density-wave stripe pattern. We characterize the novel density-wave structures, which are highly anisotropic and dependent on local, nanoindentation-induced stress concentrations, and we show how they deeply originate from intrinsic features of interelemental interactions. Furthermore, we show that these novel patterns consistently scale with the incipient plastic zone, under the indenter tip, justifying their observation at experimentally feasible nanoindentation depths.

Ultrathin Partial Ceramic Veneers in the Esthetic Zone with Tooth Whitening: A 5-year Case Report.

OBJECTIVE: This case report describes a minimally invasive approach with tooth whitening and partial ceramic veneers in the esthetic zone with a 5-year follow-up. CLINICAL CONSIDERATIONS: The patient was initially concerned about the tooth color and previous direct resin composite restorations that chipped on the incisal edges of both maxillary central incisors. Tooth whitening and partial veneers for both central incisors were recommended after clinical evaluation. Two sessions of in-office tooth whitening, first with 35% hydrogen peroxide and later with 10% carbamide peroxide from first premolar to first premolar, were provided. Minimal tooth preparation that only removed the fractured composite restorations was performed followed by placement of feldspathic porcelain ultrathin partial ceramic veneers for both central incisors. We emphasize the benefits of minimal tooth preparation paired with partial ceramic veneers and the importance of masking discolored tooth structure with such thin veneers, including potential tooth whitening. CONCLUSIONS: Overall, we demonstrate a well-planned and executed restorative procedure combining tooth whitening and ultrathin partial ceramic veneers to achieve desired results in the esthetic zone that remained successful for five years.

Polychromatic Composite and Resin Infiltration Restorations in the Esthetic Zone: A Five-year Clinical Report.

OBJECTIVE: This case report describes the use of a combination of a polychromatic resin composite restoration and resin infiltration to achieve a satisfactory esthetic outcome that has lasted over five years. CLINICAL CONSIDERATIONS: The patient's primary complaint was a desire to replace an existing stained resin composite on the facial and mesial surfaces of the maxillary left central incisor, and a white spot on the facial surface of the maxillary right central incisor. After clinical evaluation, the patient was offered either replacement of the restoration with a polychromatic restoration simulating a white spot, or a combined treatment with polychromatic composite and resin infiltration restorations, which was recommended. The patient selected the latter treatment. A putty matrix was fabricated, and a quick mock-up was done using various enamel and dentin shades of resin composite to determine proper material selection. The previous resin composite restoration was removed, and layers of new dentin, body, and enamel composite were placed. An interproximal matrix was used in order to provide ideal contour and contact. Finishing and polishing procedures were performed. The maxillary right central incisor was treated with resin infiltration in order to subdue the white spot on the facial surface. CONCLUSIONS: Polychromatic resin composite and resin infiltration restorations to replace a stained restoration and mask a white spot can achieve desired results in the esthetic zone and maintain them for five years.

Obesity as a risk factor for malignant melanoma and non-melanoma skin cancer.

The dramatic increases in incidence of both obesity and many cancers including skin cancer emphasize the need to better understand the pathophysiology of both conditions and their connections. Melanoma is considered the fastest growing cancer and rates of non-melanoma skin cancer have also increased over the last decade. The molecular mechanisms underlying the association between obesity and skin cancer are not clearly understood but emerging evidence points to changes in the tumor microenvironment including aberrant cell signaling and genomic instability in the chronic inflammatory state many obese individuals experience. This article reviews the literature linking obesity to melanoma and non-melanoma skin cancer.

Adherence to the Tobacco Control Act, 2007: presence of a workplace policy on tobacco use in bars and restaurants in Nairobi, Kenya.

INTRODUCTION: Despite extensive knowledge about effective tobacco control interventions, the prevalence of tobacco use in many middle- and low-income countries continues to rise. In these countries, public appreciation of levels of protection provided by laws and regulations on tobacco use and exposure to tobacco smoke is limited. After ratification of the Framework Convention on Tobacco Control, Kenya enacted the Tobacco Control Act, 2007, banning smoking in public places except in designated smoking areas. OBJECTIVE: To assess adherence to the Tobacco Control Act, 2007 by determining the presence of a workplace policy on tobacco use in bars and restaurants. METHODS: A survey of 176 liquor licensed bars and restaurants in Nairobi County was carried out. Their managers were asked about the presence of a workplace policy governing smoking of tobacco, and observations made on provisions that determine adherence to the Tobacco Control Act, 2007. RESULTS: Smoking took place in almost all bars and restaurants (150 (85%)). Half the establishments (86 (49%)) had a workplace policy governing tobacco use among employees, although a difference between bars (11 (23%)) and restaurants (75 (58%)) was recorded (p<0.001). Establishments at which managers had lower levels of education were less likely to have a workplace policy (p<0.001) and less likely to have 'no smoking' signs and designated smoking areas (p<0.005). CONCLUSIONS AND RECOMMENDATIONS: Kenya's implementation of the Tobacco Control Act, 2007 does not provide sufficient protection of patrons and workers in bars and restaurants. It is important to sensitise hospitality workers to the dangers of tobacco smoke. Bar and restaurants managers should have a minimum post-secondary education level. The Tobacco Control Act, 2007 requires strengthening to ensure that bars and restaurants have a smoke-free environment.

Effects of medium-chain fatty acids on performance, carcass characteristics, blood biochemical parameters and immune response in Japanese quail.

This study had the aim of evaluating the effects of medium-chain fatty acids (MCFA) on performance, carcass characteristics, some blood parameters and antibody titre against sheep red blood cells (SRBC) in quail. A total of 240 quail chicks were allotted to 4 treatments consisting of respectively 0, 1, 2 and 4 g/kg dietary MCFA. There were no significant differences in body weight, feed intake and feed conversion ratio among treatments at different stages of the experiment. MCFAs had no significant effect on breast, thigh, liver, spleen and bursa of Fabricius weight ratios. However, the relative weight of abdominal fat significantly decreased in quail receiving 0.2 and 0.4 MCFA as compared to other treatments. Concentrations of low-density lipoprotein-cholesterol (LDL), triglycerides and total cholesterol were decreased and high-density lipoprotein (HDL)-cholesterol was increased in quail chicks receiving MCFA compared with control quail chicks. The concentrations of SRBC antibody were not statistically different among treatments. It is concluded that MCFA significantly decreased LDL, triglycerides, cholesterol and abdominal fat and increased HDL in quail chicks.

Development of a specific and highly sensitive optical chemical sensor for determination of Hg(II) based on a new synthesized ionophore.

A novel optode for determination of Hg(II) ions is developed based on immobilization of a recently synthesized ionophore, 7-(1H-imidazol-1-ylmethyl)-5,6,7,8,9,10-hexahydro-2H-1,13,4,7,10 benzodioxatriaza cyclopentadecine-3,11(4H,12H)-dione, in a PVC membrane. Dioctyl sebacate was used as a plasticizer, sodium tetraphenylborate as an anionic additive and ETH5294 as a chromoionophore. The response of the optode was based on the complexation of Hg(II) with the ionophore in the membrane phase, resulting an ion exchange process between Hg(II) in the sample solution and H(+) in the membrane. The effects of pH and amounts of the ionophore, chromoionophore, ionic additive and type of plasticizer on the optode response were investigated. The selectivity of the optode was studied in the present of several cations. The optode has a linear response to Hg(II) in the range of 7.2×10(-13)-4.7×10(-4) mol L(-1) with detection limit of 0.18 pmol L(-1). The optode was successfully applied to the determination of Hg(II) in real samples.

Thermally assisted quantum annealing of a 16-qubit problem.

Efforts to develop useful quantum computers have been blocked primarily by environmental noise. Quantum annealing is a scheme of quantum computation that is predicted to be more robust against noise, because despite the thermal environment mixing the system's state in the energy basis, the system partially retains coherence in the computational basis, and hence is able to establish well-defined eigenstates. Here we examine the environment's effect on quantum annealing using 16 qubits of a superconducting quantum processor. For a problem instance with an isolated small-gap anticrossing between the lowest two energy levels, we experimentally demonstrate that, even with annealing times eight orders of magnitude longer than the predicted single-qubit decoherence time, the probabilities of performing a successful computation are similar to those expected for a fully coherent system. Moreover, for the problem studied, we show that quantum annealing can take advantage of a thermal environment to achieve a speedup factor of up to 1,000 over a closed system.

Chemical composition, cell wall features and degradability of stem, leaf blade and sheath in untreated and alkali-treated rice straw.

Three dominant morphological fractions (i.e. leaf blade (LB), leaf sheath (LS) and stem) were analysed for chemical composition and ruminal degradability in three rice straw varieties. In one variety treated with alkali, cell wall features were also characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy. The highest concentrations of cell wall carbohydrates (hemicellulose and cellulose) were observed in LS, whereas the highest concentrations of non-fibre (silica, phenolic compounds and CP) and lignin were recorded for LB. The stem had the lowest silica and hemicellulose contents but intermediate levels of other components. In terms of ruminal degradability, stem ranked higher than LB, which was followed by LS. Hemicellulose was found to be less degradable than either dry matter or cellulose in all the three fractions investigated. FTIR results indicated that the highest levels of hydrogen bonding, esterification and crystallinity within the cell wall components belonged to LS. In the alkaline treatment, these indices decreased to a larger extent for leaf fractions and a greater improvement was achieved in the degradability of LB and LS compared with that of stem. In the 24-h ruminal incubation, the silicified layer of epidermis and the underlying cell walls showed a rigid structure in the control fractions, whereas the treatment with NaOH resulted in crimping of the silicified cuticle layer and the loss of integrity in cell structure. Despite the highest silica and lignin contents observed in LB, LS showed the lowest degradability, which might be due to its high level of hydrogen bonding, crystallinity and esterification within its cell wall components as well as its high hemicellulose content.

Lipidemic responses of male broiler chickens to enzyme-supplemented wheat-soybean meal-based diets with various levels of metabolizable energy.

Effects of 2 various levels of AME (according to the manual recommendation and 100 kcal kg(-1) less than it), 2 levels of endo-beta-D-mannanase enzyme (0, 1 g kg(-1)) and 2 levels of xylanase enzyme (0 and 1 g kg(-1)) on serum lipid parameters as a 2(3) factorial arrangement were tested in 120 male broiler chicks fed wheat-soybean meal-based diet. These birds were randomly assigned to 8 experimental groups with 3 pen per group and 5 birds per pen. The serum HDL-cholesterol (HDL), LDL-cholesterol (LDL), Total-cholesterol (TC) and Triglycerides (TG) concentrations were measured at 31 and 41 day of age. The concentrations of serum TG, TC and LDL of 41-day-old birds demonstrated to be lower than those of 31-d-old (p < 0.001). Some hypolipidemic responses were observed in the broiler chicks fed on (1) Diet supplemented with only beta-mannanase, (2) Normal-AME diets supplemented with p-mannanase, (3) Normal-AME diets supplemented with Xylanse and (4) Normal-AME diets supplemented with both beta-mannanase and Xylanase (p < 0.01). In the other hand, some hyperlipidemic responses were detected in the broiler chicks fed on low-AME diets supplemented with xylanse or beta-mannanase enzymes, alone or in combination (p < 0.01). Regardless of AME, adding both xylanse and beta-mannanase to the wheat-soybean meal-based diets have both hyperlipidemic and hypolipidemic effects together (p < 0.01).

Prenatal stress enhances severity of atherosclerosis in the adult apolipoprotein E-deficient mouse offspring via inflammatory pathways.

Atherosclerosis is the underlying cause of cardiovascular disease and stroke. Endothelial cell dysfunctions are early events in atherosclerosis, resulting in the recruitment of circulating monocytes. The immune system can elicit an inflammatory response toward the atherosclerotic lesion, thereby accelerating lesion growth. Risk factors for atherosclerosis include hypertension, smoking, stress perception or low birth weight. As prenatal stress challenge decreases the birth weight and affects the offspring's postnatal immune response, we aimed to investigate whether prenatal stress contributes to the development of atherosclerosis in mice. Syngenic pregnant apolipoprotein E-deficient (apoE-/-) dams were exposed to sound stress on gestation days 12.5 and 14.5. The presence and size of atherosclerotic plaques in the offspring at the age of 15 weeks was evaluated by histomorphology, accompanied by flow cytometric analysis of the frequency and phenotype of monocytes/macrophages and regulatory T (Treg) cells in the blood. Further, cytokine secretion of peripheral blood lymphocytes was analyzed. In response to prenatal stress challenge, an increased frequency of large atherosclerotic plaques was detectable in apoE-/- offspring, which was particularly profound in females. Prenatal stress also resulted in alterations of the offspring's immune response, such as a decreased frequency of Treg cells in blood, alterations of macrophage populations in blood and an increased secretion of inflammatory cytokines. We provide novel evidence that prenatally stressed adult offspring show an increased severity of atherosclerosis. As Treg cells are key players in dampening inflammation, the observed increase in atherosclerosis may be due to the lack of Treg cell frequency. Future interdisciplinary research is urgently required to understand the developmental origin of prenatal stress-induced atherosclerosis. The availability of our model may facilitate and foster such research endeavors.

Quantum annealing with manufactured spins.

Many interesting but practically intractable problems can be reduced to that of finding the ground state of a system of interacting spins; however, finding such a ground state remains computationally difficult. It is believed that the ground state of some naturally occurring spin systems can be effectively attained through a process called quantum annealing. If it could be harnessed, quantum annealing might improve on known methods for solving certain types of problem. However, physical investigation of quantum annealing has been largely confined to microscopic spins in condensed-matter systems. Here we use quantum annealing to find the ground state of an artificial Ising spin system comprising an array of eight superconducting flux quantum bits with programmable spin-spin couplings. We observe a clear signature of quantum annealing, distinguishable from classical thermal annealing through the temperature dependence of the time at which the system dynamics freezes. Our implementation can be configured in situ to realize a wide variety of different spin networks, each of which can be monitored as it moves towards a low-energy configuration. This programmable artificial spin network bridges the gap between the theoretical study of ideal isolated spin networks and the experimental investigation of bulk magnetic samples. Moreover, with an increased number of spins, such a system may provide a practical physical means to implement a quantum algorithm, possibly allowing more-effective approaches to solving certain classes of hard combinatorial optimization problems.

Local anisotropy in globally isotropic granular packings.

We report on two-dimensional computer simulations of frictionless granular packings at various area fractions φ above the jamming point φ(c). We measure the anisotropy in coarse-grained stress ε(s) and shear modulus ε(m) as functions of coarse-graining scale, R. ε(s) can be collapsed onto a master curve after rescaling R by a characteristic length scale ξ and ε(s) by an anisotropy magnitude A. Both A and ξ accelerate as φ→φ(c) from above, consistent with a divergence at φ(c). ε(m) shows no characteristic length scale and has a nontrivial power-law form, ε(m)~R(-0.62), over almost the entire range of R at all φ. These results suggest that the force chains present in the spatial structure of the quenched stress may be governed by different physics than the anomalous elastic response near jamming.

Progressive nodular histiocytosis: a case report with literature review, and discussion of differential diagnosis and classification.

Histiocytoses are a heterogeneous group of disorders which are difficult to categorize because of overlapping clinical and microscopic features, and incompletely understood mechanisms of cellular origin and triggers of proliferation. Progressive nodular histiocytosis (PNH) is a rare non-Langerhans cell histiocytic (NLH) disorder. We present the case of a 34-year-old woman with PNH, who has involvement of the back, head and neck, face, and uniquely, extensive involvement of the posterior pharynx and larynx, which has shown progressive worsening and deformity over a 7-year course. Clinically it is best classified as PNH, although it microscopically closely resembles juvenile and adult xanthogranulomatosis. This study reinforces the concept that the NLH is a closely related group of disorders, possibly representing a spectrum of a single underlying process.

The impact of dendritic cells on angiogenic responses at the fetal-maternal interface.

The success of mammalian pregnancy is highly dependent on the establishment of an adequate blood supply to support the metabolic demands of the growing embryo and fetus. New blood vessels develop from pre-existing vessels in a multi-step process called angiogenesis, which is tightly regulated in time and space and has proven to be crucial in several physiological situations such as wound healing, follicular development and cyclic endometrial growth. As in other tissues, the regulation of angiogenic responses in the decidua depends on a delicate balance between stimulatory and inhibitory signals. In particular, trophoblasts and decidual NK cells are well-recognized components of the uterine signaling network with a proven ability to produce growth factors and cytokines that modulate endothelial cell responsiveness during pregnancy. In mice and humans, dendritic cells are also considered an important regulatory component during pregnancy, mainly due to their role in the establishment of maternal immunologic tolerance. However, the recent finding that dendritic cell subsets can promote angiogenesis in a variety of physiopathological settings suggests that regulatory functions of these cells may go beyond the promotion of maternal tolerance, having impact on other processes such as decidualization and placentation and the vascular changes associated to them. Current evidence on dendritic cell-derived angiogenic signals and their potential implications in vascular development during gestation are reviewed and discussed herein.

Preparation and characterization of ibuprofen microspheres.

Ibuprofen was microencapsulated with Eudragit RS using an o/w emulsion solvent evaporation technique. The effects of three formulation variables including the drug:polymer ratio, emulsifier (polyvinyl alcohol) concentration and organic solvent (chloroform) volume on the entrapment efficiency and microspheres size distribution were examined. The drug release rate from prepared microspheres and the release kinetics were also studied. The results demonstrated that microspheres with good range of particle size can be prepared, depending on the formulation components. The drug:polymer ratio had a considerable effect on the entrapment efficiency. However, particle size distribution of microspheres was more dependent on the volume of chloroform and polyvinyl alcohol concentration rather than the drug:polymer ratio. The drug release pattern showed a burst effect for all prepared microspheres due to the presence of uncovered drug crystals on the surface. It was shown that the release profiles of all formulations showed good correlation with the Higuchi model of release.

Spontaneous kidney allograft rupture.

Spontaneous renal allograft rupture is one of the most dangerous complications of kidney transplantation, which can result in graft loss. This condition needs immediate surgical intervention. Conservative management has dismal results. Its prevalence varies from 0.3% to 3%. Rupture occurs in first few weeks after transplantation. Predisposing factors for graft rupture are acute rejection, acute tubular necrosis, and renal vein thrombosis. There are growing reports about successful results of repairing these ruptured kidneys. In this study, we reviewed the medical records of 1682 patients who received kidney allografts from living donors from 1986 through 2003. There were six (0.35%) cases of renal allograft rupture. All were preceded by acute graft rejection. They were treated with antirejection medications. In first three cases, the kidney allografts were removed because the procedure of choice in this situation is graft nephrectomy; but in three next cases we repaired the ruptured grafts with good results in two of them. In conclusion, the procedure of choice for kidney allograft rupture is graft repair.

Stem cell factor and interleukin-4 increase responsiveness of mast cells to substance P.

The response of mast cells (MC) to non-IgE-mediated stimulation is critically dependent on the population of MC examined. The neuropeptide Substance P (SP) has been reported to activate connective tissue-type MC (CTMC), while mucosal MC (MMC) are not activated by SP. We examined the effect of stem cell factor (SCF) plus interleukin-4 (IL-4) on SP-initiated activation of bone marrow-derived MC (BMMC). Mouse MC, derived from a culture of BM cells with IL-3, were subsequently treated with recombinant SCF plus IL-4 for 6 days. Responsiveness to SP was monitored measuring beta-hexosaminidase and lipid mediator release. Histochemical staining, histamine analysis, and granule protease expression were achieved to characterize the cells. In contrast to IL-3 grown cells, SCF/IL-4-exposed cells showed functional responsiveness to release beta-hexosaminidase (42.25% +/- 1.46% at SP concentration of 100 microM) and produce leukotriene C(4) (LTC(4)) (7.4 +/- 1.5 ng/10(6) cells)/prostaglandin D(2) (PGD(2)) (2.0 +/- 0.3 ng/10(6) cells) upon stimulation by SP. The increase in sensitivity of the cells to SP was not due to differentiation into CTMC, as the cells remained heparin negative. Both SCF and IL-4 were needed because SCF or IL-4 alone were insufficient to keep cells viable after 3 to 4 days post coculture. SP-induced secretion from BMMC cultured in medium containing SCF plus IL-4 (25.76% +/- 1.83%) was higher in comparison with cells cultured with SCF plus IL-3 (8.85% +/- 0.68%).These findings indicate that temporal changes in cytokine expression can influence the sensitivity of MC to non-immunologic stimuli. Local cytokine production leading to an increase in MC responsiveness to SP and inducing secretion of granule content and lipid generation may, therefore, propagate and worsen inflammatory conditions.

Protein kinase C and a calcium-independent phospholipase are required for IgG-mediated phagocytosis by Mono-Mac-6 cells.

Mono-Mac-6 (MM6) human monocytes ingest IgG-opsonized particles better than other human cell lines. We compared the phagocytic signaling pathway in MM6 with human monocytes. MM6 expressed FcgammaRI at levels similar to monocytes, whereas FcRgammaII expression was approximately double. MM6 ingested IgG-opsonized erythrocytes (EIgG) in a calcium-independent manner. Incubation of MM6 with bromoenol lactone, an inhibitor of the phagocytic phospholipase (pPL), coordinately decreased phagocytosis and pPL activity. This inhibition was overcome by exogenous arachidonic acid, suggesting that phagocytosis requires pPL activation and arachidonic acid release. MM6 phagocytosis was inhibited with staurosporine and activated with diacylglycerol, supporting a role for protein kinase C (PKC) in this process. The pPL activators mastoparan and melittin restored phagocytosis to PKC-inhibited cells, suggesting that pPL lies downstream from PKC. These results suggest that the MM6 signal transduction pathway for IgG-mediated phagocytosis is similar to that of monocytes (PKC-->pPL-->arachidonic acid-->phagocytosis). The results are discussed in the context of the finding that MM6 exhibit low phagocytosis relative to monocytes and thus may represent an attractive cell line for molecular manipulation in "recovery of function" studies.