Electrophysiologic and electrocardiographic aspects of the transplanted heart

The authors suggest that academic institutions build business-oriented policies and practices into the development of any nurse-run clinic to set the stage for financial independence when special or development funding ends. One university-affiliated program that provides 4,000 to 5,000 annual visits drastically changed its strategies when threatened with closure after free rent and other subsidies were withdrawn. The growing emphasis on ambulatory care roles for nurses at all levels makes such clinics critical to the success of the broad-based curricula of nursing education programs, as well as the clinic's value to communities they serve. Funding difficulties frequently threaten the existence of such nurse-run clinics once the initial grant funding is no longer available. This has caused a new emphasis on running such clinics in a business-wise manner. Among the strategies initiated were: direct full-pay at the time of service; a realistic business management plan; aggressive planned marketing; contracts and agreements with other agencies; obtaining provider status with selected HMOs.     

Investigation of Ablation Efficiency of Stainless Steel Using Pulsed Lasers in Burst Mode

Due to its high corrosion resistance and mechanical properties, stainless steel is commonly used in various industrial applications. Although different types of stainless steel are similar in their chemical composition, they can differ significantly in their thermal diffusivity. This property is relevant in the ability of a material to conduct heat and thus, in laser processing. In this frame, this study compares the ablation efficiency and characteristics of polished stainless steel samples of the alloys AISI 304, AISI 420, and AISI 316Ti. They are irradiated with single ultrashort pulses having pulse durations between 250 fs and 10 ps as well as using GHz burst modii. The goal is to investigate the differences in both the ablation threshold and the ablation rate to improve the ablation efficiency. The results show that shorter pulse durations lead to a more efficient ablation process. On the other hand, GHz bursts are found to be, in general, less efficient. In addition, there is a significant difference in the surface morphology depending on the process parameters. The differences in the thermal diffusivity do not significantly influence the ablation threshold fluence but surface morphology and the ablation rate.     

The Role of NLRP3 Inflammasome Activation and Oxidative Stress in Varicocele-Mediated Male Hypofertility

Varicocele (VC) is the most common abnormality identified in men evaluated for hypofertility. Increased levels of reactive oxygen species (ROS) and reduced antioxidants concentrations are key contributors in varicocele-mediated hypofertility. Moreover, inflammation and alterations in testicular immunity negatively impact male fertility. In particular, NLRP3 inflammasome activation was hypothesized to lead to seminal inflammation, in which the levels of specific cytokines, such as IL-1β and IL-18, are overexpressed. In this review, we described the role played by oxidative stress (OS), inflammation, and NLRP3 inflammasome activation in VC disease. The consequences of ROS overproduction in testis, including inflammation, lipid peroxidation, mitochondrial dysfunction, chromatin damage, and sperm DNA fragmentation, leading to abnormal testicular function and failed spermatogenesis, were highlighted. Finally, we described some therapeutic antioxidant strategies, with recognized beneficial effects in counteracting OS and inflammation in testes, as possible therapeutic drugs against varicocele-mediated hypofertility.     

Preparation and swelling properties of homopolymeric alginic acid fractions/poly(N‐isopropyl acrylamide) graft copolymers

Graft copolymers of crosslinked poly(N‐isopropyl acrylamide) (PNIPAAm) and homopolyguluronic acid (GG) and homopolymannuronic acid (MM) fractions of alginic acid were synthesized. MM and GG block fractions were obtained by partial acid hydrolysis of the alkaline extract from the brown seaweed Macrocystis pyrifera. The conjugation of these block fractions with the synthetic polymer was achieved by amidation with crosslinked PNIPAAm functionalized with an amino group at the end of the polymer chain. The structure of conjugates was determined by Fourier transform infrared and NMR spectroscopy. Atomic force microscopy of the graft copolymer GG‐g‐PNIPAAm showed a regular porous pattern, whereas the MM‐g‐PNIPAAm graft copolymer showed a regular netlike structure. Aqueous solutions of the synthesized graft copolymers afforded hydrogels by stirring with 0.1M CaCl₂. The hydrogels showed a well‐defined stimulus–response to temperature and pH. The swelling, thermal, and pH characterizations demonstrated the superior properties of the GG‐g‐PNIPAAm hydrogel over the MM‐g‐PNIPAAm hydrogel. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42398.     

Avoiding structure degradation during activation of ordered mesoporous carbons

Hierarchical micro–mesoporous carbons with high porosity development and ordered structure were prepared. The innovative proposal consists in developing microporosity in ordered mesoporous carbon by chemical activation in template presence in order to minimize the structural damage. Thus, we have directly carried out the chemical activation of a mesoporous carbon/silica composite with KOH. The effect on mesoporous ordered structure of both KOH/carbon ratio and activation temperature has been studied. Following chemical activation the specific surface area is increased from 341 to 1757 m²/g and the micropore volume becomes almost six times larger than initial value. Although a slight widening of the mesopore distribution and an increase in the mesopore volume has been observed during activation, TEM and XRD results reveal an excellent conservation of the ordered mesoporous structure during activation even at conditions well above the limits that a CMK-3 type carbon can resist.     

Rectal hemorrhage as a first sign of renal cell adenocarcinoma

We present a 3-year-old patient with stenotic kinking of the left internal carotid artery (ICA) who developed an ischaemic infarction of the left brain hemisphere followed by severe neurological sequelae after a prolonged generalized seizure. At time of the seizure the boy was in biological remission of a nephrotic syndrome and received prednisolone and cyclosporin A (CsA) treatment. The haemodynamic consequences of inborn kinking of the ICA is discussed controversely in the literature. The presented case shows that stenotic kinking of the ICA may significantly impair the blood flow towards the homolateral hemisphere and therefore may result in an ischaemic infarction. The influence of CsA on seizure activity is discussed. CONCLUSION: This case provides clinical and radiological evidence supporting an association between stenotic kinking of the carotid artery and homolateral hemispheric brain infarction.     

Tools to maintain postharvest fruit and vegetable quality through the inhibition of ethylene action: a review

Ethylene is a plant hormone controlling a wide range of physiological processes in plants. During postharvest storage of fruit and vegetables ethylene can induce negative effects including senescence, over-ripening, accelerated quality loss, increased fruit pathogen susceptibility, and physiological disorders, among others. Apart from the endogenous ethylene production by plant tissues, external sources of ethylene (e.g. engine exhausts, pollutants, plant, and fungi metabolism) occur along the food chain, in packages, storage chambers, during transportation, and in domestic refrigerators. Thus, it is a great goal in postharvest to avoid ethylene action. This review focuses on tools which may be used to inhibit ethylene biosynthesis/action or to remove ethylene surrounding commodities in order to avoid its detrimental effects on fruit and vegetable quality. As inhibitors of ethylene biosynthesis and action, good results have been found with polyamines and 1-methylcyclopropene (1-MCP) in terms of maintenance of fruit and vegetable quality and extension of postharvest shelf-life. As ethylene scavengers, the best results can be achieved by adsorbers combined with catalysts, either chemical or biological (biofilters).     

Steady‐State and Dynamic Reactor Models for Hydrotreatment of Oil Fractions: A Review

The modeling of catalytic hydrotreatment reactors for petroleum fractions have been classified in several ways, for example steady‐state and dynamic, pseudohomogeneous, and heterogeneous, and so on. Depending on the system to be modeled, operating conditions and type of feedstock, these approaches could exhibit some advantages and disadvantages, wide scopes and limitations. In this review, the discussion about those modeling aspects, already published, is used to develop a generalized reactor model, which can be simplified in order to derive each single model previously reported. Some guides to estimate model parameters are also given.     

Development of Low-Cost Remote-Control Generators Based on BiTe Thermoelectric Modules

This paper presents a new thermogenerator based on moderate-temperature (up to 175°C) BiTe modules available on the open market. Despite this handicap relative to commercial thermogenerators based on high-temperature proprietary-technology PbBi modules (up to 560°C), this new design may become economically competitive due to its innovative thermal sink. Our thermal sink is based on a free-convection water loop built with standard tubing and household hot-water radiators, leading to a more practical, modular design. So, the specific cost of about 55,000 USD/kW obtained for this 120-W prototype is improved to 33,000 USD/kW for a 1-kW unit, which represents about half the price of commercial thermogenerators. Moreover, considering recently launched BiTe modules (that withstand up to 320°C), our proposition could have an even more favorable outlook.