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In the search for new high-temperature superconductors, it has been proposed that there are strong similarities between the fluoroargentate AgF2 and the cuprate La2 CuO4 . We explored the origin of the possible layered structure of AgF2 by studying its parent high-symmetry phase and comparing these results with those of a seemingly analogous cuprate, CuF2 . Our findings first stress the large differences between CuF2 and AgF2 . Indeed, the parent structure of AgF2 is found to be cubic, naturally devoid of any layering, even though Ag2+ ions occupy trigonal sites that, nevertheless, allow the existence of a Jahn-Teller effect. The observed Pbca orthorhombic phase is found when the system is cooperatively distorted by a local E⊗e trigonal Jahn-Teller effect around the silver sites that creates both geometrical and magnetic layering. While the distortion implies that two Ag2+ -F- bonds increase their distance by 15 % and become softer, our simulations indicate that covalent bonding and interlayer electron hopping is strong, unlike the situation in cuprate superconductors, and that, in fact, exfoliation of individual planes might be a harder task than previously suggested. As a salient feature, these results prove that the actual magnetic structure in AgF2 is a direct consequence of vibronic contributions involved in the Jahn-Teller effect. Finally, our findings show that, due to the multiple minima intrinsic to the Jahn-Teller energy surface, the system is ferroelastic, a property that is strongly coupled to magnetism in this argentate.

Chronic inflammation, protein-energy wasting, and poor physical functioning are highly prevalent among patients with chronic kidney disease (CKD). These factors are associated with disability and increase of cardiovascular risk. The aim of this study is to evaluate the effects of exercise training during hemodialysis (HD) sessions on physical functioning, body composition, and nutritional and inflammatory status. We performed a prospective intervention study including patients on prevalent HD therapy. Patients were evaluated at baseline visit by Rehabilitation and Physiotherapy specialists and the exercise program was adapted to each patient's physical capacity. In addition to demographic, clinical, body composition and functional ability data, serum markers regarding nutritional and inflammatory status were collected at baseline and after 3 months of exercise training. We observed a significant improvement after 3-month follow-up in functional ability (6 minute walk test [6MWT] [403.15 ± 105.4 vs 431.81 ± 115.5 m, P < .001], sit-to-stand repetitions in 30 seconds [12.2 ± 4.2 vs 14.1 ± 5.0 repetitions, P = .003] and dynamometry [24.5 ± 11.9 vs 29.5 ± 12.5 kg, P < 0.001]), body composition with increase of body mass index (BMI) (23.7 ± 4.4 vs 24.1 ± 4.7 kg/m2 , P = 0.01) at the expense of lean tissue index (LTI) (14.9 ± 3.7 vs 16.2 ± 2.9 kg/m2 , P = 0.038) and lipid parameters with LDL-cholesterol decrease (70.2 ± 17.9 vs 64.9 ± 21.3 mg/dL, P = .03) and lower serum triglyceride levels (125.8 ± 54.0 vs 108.2 ± 44.6 mg/dL, P = .006). In addition, we found a decrease in iron (155.6 ± 148.2 vs 116.7 ± 110.8 mg, P = .029) and erythropoietin (117.5 ± 84.2 vs 99.2 ± 74.5 μg, P = .023) requirements. The implementation of exercise training programs during HD can improve physical functioning, body composition and lipid and anemia profile. Supervised exercise programs could be included as part of HD patient care to improve physical capacity in these patients.

Background Iron (Fe) plays a crucial role in several fundamental processes, including erythropoiesis, cellular metabolism, and in cardiovascular disease. The aim of this work was to contribute to a better understanding of the physiology of and recovery from Fe deficiency by studying how fermented milk consumption affects vascular biomarkers during Fe repletion. Results The deleterious cardiovascular biomarkers cytokine-induced neutrophil chemoattractant 1, connective tissue growth factor (CTGF), interleukin-6, monocyte chemoattractant protein-1 (MCP-1), inhibitor of tissue plasminogen activator 1 total, metallopeptidase inhibitor 1 (TIMP-1), tumor necrosis factor alpha, vascular endothelial growth factor (VEGF), sE-selectin, and soluble intercellular adhesion molecule 1 (sICAM-1) decreased after fermented goat milk consumption in groups of fed animals either with normal Fe or Fe overload with respect to rats fed with fermented cow milk. The beneficial cardiovascular biomarkers caveolin-1 and adiponectin were higher in both control and anemic rats fed fermented goat milk either with normal Fe or Fe overload with respect to fermented cow milk. Anemia decreased TIMP-1 in rats fed fermented goat milk with Fe overload, whereas there was increased CTGF and MCP-1 in animals fed fermented cow milk with either normal or Fe overload. In addition, Fe overload increased VEGF. Conclusion Fermented goat milk consumption improves hematological status and promotes beneficial metabolic responses, which may attenuate cardiovascular risk factors during anemia recovery and iron overload to lessen the inflammatory response, macrophages activation and atherosclerosis development. © 2018 Society of Chemical Industry.

The objective of this research was to explore the advantages of apple slices dehydration (cv. Granny Smith) using a Refractance Window (RW) with and without osmotic dehydration as pretreatment and compared with conventional hot‐air drying considering the quality attributes such as color and texture. For pretreatment, the apple slices were osmotically dehydrated and coupled to a moderate electric field (9.3 V/cm) using a sucrose solution (45°Brix) at 40°C until an Aw = 0.95 was achieved. Then, apple slices (with and without pretreatment) were dehydrated using RW at 55, 75, and 95°C and compared with conventional hot‐air drying at 55°C as a control. The results showed that with dehydration using RW, both with and without pretreatment at 95°C, it was possible to achieve a similar quality of apple slices when compared with conventional hot‐air drying at 55°C, but with a significant reduction in processing time. Additionally, the dehydration process using RW presented anomalous diffusion behavior on apple slices with an α > 1. PRACTICAL APPLICATIONS: Refractance Window (RW) is a technology used for dehydration of fruit and vegetables slices and pulp based on the refractance properties of wet materials. RW has reported promising results in processing time reduction as compared with conventional dehydration methods. In addition, the quality of the end products by RW is higher as compared with conventional drying methods. In this research, we have showed that the final product (dehydrated apple slices) using RW attained quality values (color and texture) similar to those obtained with osmotic dehydration (OD) coupled with moderate electric field (MEF)/hot‐air drying. However, the time spent by RW (50 min) was much lower than OD coupled with MEF/hot‐air drying (240 min). Then, the main advantage of RW is the capacity to dehydrate fruit and vegetables materials using temperatures around 100°C, which allow both, reduce processing time and also attain high‐quality retention.

Summary Apples are a widely consumed fruit and have a high polyphenol content. The aim of this study was to analyse the combined effects of osmotic dehydration (OD) and ohmic heating (OH) with a pulsed vacuum (PV) on polyphenol retention during the stored refrigeration of apple cubes. Treatments were performed using a 65°Brix sucrose solution at 30, 40 or 50 °C for 120 min, and then, samples were stored for 28 days at 5 °C. OH provides an electric field of 13 V cm−1, and a pulsed vacuum was applied for 5 min at the beginning of the process. The results indicated that a lower temperature process (30–40 °C) resulted in the retention of more polyphenol compounds after treatment than a higher temperature process (50 °C). Nevertheless, during refrigerated storage, we observed that 50 °C preserved these compounds better due to polyphenol oxidase inactivation. PVOD/OH treatment at 50 °C was determined to be the best retention of polyphenols from the fresh apple for dehydrating apples.

Background: Iron deficiency anemia (IDA) is one of the most common nutritional problems in the world, and it is accepted that reactive oxygen species (ROS) production is altered during IDA. The aim of this study was to assess the influence of fermented goat and cow milks on enzymatic antioxidant activities and gene expression, and their role in protecting from oxidative damage during anemia recovery.; Results: After feeding the fermented milks-based diets (cow or goat), a significant elevation of some antioxidant endogenous enzymes was found, together with an increase in total antioxidant status (TAS), and a decrease in 8-hydroxy-2'-deoxyguanosine (8-OHdG) was recorded in animals consuming fermented goat milk-based diet. In contrast, DNA strand breaks, hydroperoxides, 15-F2t-isoprostanes and protein carbonyl groups were lower in some tissues in animals fed fermented goat milk-based diet, revealing an improvement in both systemic and cellular antioxidant activity of plasma and tissues due to fermented goat milk consumption.; Conclusion: Fermented goat milk consumption induces a protective increase in TAS together with lower oxidative damage biomarkers, revealing that the milk protects main cell bioconstituents (lipids, protein, DNA, prostaglandins) from evoked oxidative damage during anemia recovery. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

Studies about Coenzyme Q10 (CoQ10 ) supplementation on strenuous exercise are scarce, especially those related with oxidative stress associated with physical activity and virtually nonexistent with the reduced form, Ubiquinol. The objective of this study was to determine, for the first time, whether a short-term supplementation with Ubiquinol can prevent oxidative stress associated to strenuous exercise. The participants (n = 100 healthy and well trained, but not on an elite level) were classified in two groups: Ubiquinol (experimental group), and placebo group (control). The protocol consisted of conducting two identical strenuous exercise tests with a rest period between tests of 24 h. Blood and urine samples were collected from the participants before supplementation (basal value) (T1), after supplementation (2 weeks) (T2), after first physical exercise test (T3), after 24 h of rest (T4), and after second physical exercise test (T5).The increase observed in the lactate, isoprostanes, DNA damage, and hydroperoxide levels reveals the severity of the oxidative damage induced by the exercise. There was a reduction in the isoprostanes, 8-OHdG, oxidized LDL, and hydroperoxydes in the supplemented Ubiquinol group, an increase in total antioxidant status, fat soluble antioxidant (both plasma and membrane), and CAT activity. Also, NO in the Ubiquinol-supplemented group was maintained within a narrow range. Oxidative stress induced by strenuous exercise is accumulative and increases transiently in subsequent sessions of physical activity. A short-term supplementation (2 weeks) with Ubiquinol (200 mg/day) before strenuous exercise, decreases oxidative stress and increases plasma NO, fact that could improve endothelial function, energetic substrate supply, and muscle recovery after strenuous exercise. © 2016 BioFactors, 42(6):612-622, 2016.

Supplementation with L-arginine or fresh food with high content of this amino acid is associated with favorable effects in the metabolic control of diabetes. We aimed to determine whether supplementation with apples enriched with L-arginine offer additional benefits compared to L-arginine by itself in a preclinical study of diabetes. This study combines food-engineer technologies with in vivo and in vitro analysis. In vitro experiments show that cells derived from non-diabetic animals and exposed to high glucose (25 mM, 12 H) and cells isolated from alloxan-induced diabetic animals exhibited a reduction (∼50%) in the L-arginine uptake. This effect was reverted by L-arginine pretreatment (12 H) in both the normal and diabetes-derived cells. In preclinical studies, normoglycemic (n = 25) and diabetic groups (n = 50) were divided into subgroups that received either L-arginine (375 mg/kg per 10 days) or apple enriched with L-arginine or vehicle (control). In a preliminary analysis, supplementation with L-arginine by itself (50%) or apple enriched with L-arginine (100%) improve survival rate in the diabetic group compared to control (0%) at the end of the follow up (17 days). This phenomenon was associated with a partial but sustained high plasma level of L-arginine, as well as plasma concentration of nitrites and insulin in the L-arginine or apple + L-arginine groups after supplementation. Apple + L-arginine supplementation in diabetic animals induced the highest and longest effects in the level of these three markers among the studied groups. Therefore, apple enriched by L-arginine offers more benefits than L-arginine by itself in this preclinical study.

The article presents the design, realization, and experimental validation of a GaN-based hybrid Doherty power amplifier for WiMAX base-stations at 3.5 GHz. The amplifier exploits, for the first time as far as authors' knowledge goes, a second harmonic tuning scheme designed to further improve the efficiency in the Doherty region. The amplifier is based on a packaged GaN HEMT from Cree, and shows a saturated output power exceeding 43.2 dBm (21.5 W), a Doherty high-efficiency region in excess of 6 dB output back-off, with a first peak and maximum drain efficiency at saturation of 55 and 61%, respectively. The amplifier, with baseband digital predistortion, is compliant with the standard emission mask in the presence of a 9 dB peak to average power ratio WiMAX input and exhibits a weighted efficiency as high as 40%. The performances of the designed amplifier favorably compare with the state of the art for the same application.

This paper illustrates that the inclusion of system-level safety analysis, in this case Systems Theoretic Accident Model and Processes (STAMP)-based Process Analysis (STPA), in conjunction with systems engineering tools, such as Axiomatic Design, in the conceptual design phase of complex socio-technical systems is critical to capturing key functional and non-functional requirements early in the development lifecycle. In particular, capturing safety-related non-functional requirements during the conceptual design phase can help avoid operational scenarios that result in conditions hazardous to life and property. In addition, such an approach prevents costly “add-ons” later in the design and implementation phases of the system life cycle. We illustrate this through the design of a “smart box” that enables large-scale integration of distributed Renewable Energy Systems (RES) into the electrical power grid to more effectively and efficiently manage overall power demands across the grid. In the conceptual design of this system we arrive at a first set of functional requirements using stakeholder interviews and the Axiomatic Design approach. We then present a detailed discussion of the STPA tool and its application to our “smart box” concept, to arrive at unique safety-related requirements identified through application of the STPA.

This article describes the design, realization, and characterization of a set of hybrid medium-power RF power amplifiers, based on a commercial packaged GaN HEMT and developed through a low-cost microstrip process. Two different design solutions suitable for wireless applications are presented: the first, intended for a constant envelope modulation (with reference to the GSM standard) is a Class F amplifier exhibiting at 900 MHz an efficiency of 72% with an output power of 37.5 dBm; the second, optimized for nonconstant envelope signals with high dynamics (with reference to the UMTS WCDMA standard) is a Doherty amplifier showing, at 2.14 GHz, an efficiency higher than 40% at 6 dB of output power back-off with a maximum output power of 40 dBm

The effect of osmotic dehydration (OD) at atmospheric pressure and vacuum impregnation (VI) treatments on some physiochemical parameters of papaya (a x ,ph, color, firmness, and microstructure) was analysed. Osmotic treatments were carried ont on papapaya with 55°Bris and 65°Brix sucrose solutions at 30 °C. VI with 65°Brix osinatic sohition was the most effectise in redin log a due to the highest senrsre gain during osmotic treatment. Color differences were auseciated to loss of clarity in line with transparency gain. Scanning electron microscopy observations show that osmotic dehydration caused strape changes and the reduction of papaya cells; also differences in microstructural features were observed batween OD treated and VI treated samples. Moreover, the largest flrmness observed in VI samples sempared with OD treatments was associated with the thlcknress of the middle lamella between cells, whith was greater in VI than OD treatments. Improvement in rexture and palatability of papaya was obtained with VI rather than OD treatment compared with fresh papaya.

UNLABELLED Genital human papillomavirus (HPV) infection was studied in 150 women after conization for cervical intraepithelial neoplasia grade three (CIN III). Colposcopically directed biopsies were taken from the cervix and vulva for histopathological diagnosis. 77 specimens were further analyzed immunohistochemically for the presence of HPV capsid antigen. In ten randomly selected cervical biopsies cellular DNA was dot blot hybridized with HPV 6/11 and 16/18 DNA probes. Genital warts were seen in 10 (7%) of the patients. Among the routine cytological smears, HPV infection was only reported in 3 (2%). In 87/142 (61%) of the cervical tissues koilocytes were found. A further 9/142 (6%) associated with CIN. Of the vulvar biopsies 91/145 (63%) contained koilocytes. A further 12/145 (8%) were associated with vulvar intraepithelial neoplasia. HPV capsid proteins were detected in 35/77 (45%) of the cervical and in 20/41 (49%) of the vulva biopsies. All cervical DNA samples hybridized with probes for HPV 6/11 and two also reacted with the HPV 16/18 probes. CONCLUSION A latent HPV infection of the cervix or vulva, can be detected in 85% of the women previously treated for CIN III by conization.

The fate of labeled palmitate, stearate, and acetate administered to the yellow clam, Mesodesma mactroides, was investigated. 1(-14)C palmitic and 1(-14)C stearic acids were oxidized to CO2 to a limited extent. They were mainly incorporated in diacylglycerols and triacylglycerols and were converted to higher homologs. After administration, palmitic acid was converted to stearic and oleic acids, whereas administered stearic acid was converted to 18:1, 18:2, 20:1, and 20:2 acids. Labeled acetate was readily included by the clam in 12:0, 14:0, 14:1, 15:0, 16:1, 16:1, 16:2, 18:2, 18:1, 18:2, 20:1, 20:2, and 20:3 acids.

Recombinant DNA molecules which contained a subgenomic fragment of the hepatitis B virus (HBV) genome, the pML2 vector and the bovine papillomavirus type 1 (BPV) genome were constructed. The HBV fragment includes the entire transcription unit for the hepatitis B surface antigen (HBsAg). After propagation in Escherichia coli, the recombinant plasmids were cleaved with endonucleases SalI and PvuI to eliminate most of the bacterial sequences before transfection of mouse C127 cells. Foci were observed 10--14 days after transfection. Cells from selected foci were cloned and the supernatants were assayed for the presence of HBsAg. Most of the clones tested were found to secrete HBsAg particles into the growth medium. These particles appear to be similar to the 22 nm particles present in the serum of HBV chronic carriers. SDS-polyacrylamide gel electrophoresis revealed that the particles contain two polypeptides, probably representing the glycosylated and unglycosylated forms of the HBsAg major polypeptide. An analysis of DNA from the transformed clones revealed that they contain multiple extra-chromosomal copies of the recombinant, which, however, had suffered rearrangement.

The lipid composition of the yellow clam, Mesodesma mactroides, that lives in the northern beaches of the Buenos Aires province of Argentina was studied. The main nonpolar lipids are triglycerides and alkoxyglycerides. Phosphatidyl choline, phosphatidyl ethanolamine, and phosphatidyl serine are the main phospholipids. The predominant fatty acids are 16:0, 16:1omega7, 18:0, 18:1omega9, 20:5omega3, and 22:6omega3. They are mainly provided by the clam's food and stored in the hepatopancreas. The content of polyunsaturated acids increases in summer together with an increase in nonpolar lipids and is correlative with an increase in phytoplankton in the sea water. Sexual maturity modifies the lipid composition of gametes.

Although human papillomavirus (HPV) is involved in the etiology of cervical carcinoma, there are no cervical carcinoma-specific HPV serologic tests available. We investigated the presence of broadly cross-reactive IgA antibodies to papillomavirus (PV) in cervico-vaginal secretions from patients with condylomata and cervical intraepithelial neoplasia (CIN). Purified bovine PV (BPV) virions were used as antigen in an enzyme-linked immunosorbent assay (ELISA). Forty-two women whose ages ranged from 20 to 50 participated in the study. Eight of 9 patients with CIN had IgA antibodies against PV in their cervical secretions. Three of 9 patients with koilocytosis and condylomas but no CIN had IgA antibodies to PV. Six of 24 women with normal Pap-smear and colposcopy also had IgA antibodies against PV in their cervical secretions. The proportion of IgA-positive cervical secretions was significantly higher in the CIN group than in the normal group (p less than 0.005). Our data suggest that IgA antibodies to PV may be a useful marker for CIN.