The formation of self-organized nanoporous anodic films on Type 304 stainless steel in fluoride-containing ethylene glycol electrolyte is reported. A key factor in the formation of the nanoporous ...anodic films is the water concentration in the electrolyte, which must be 0.3moldm−3 or less for the present conditions of film formation, although nanoporous anodic films have been formed on iron at higher water concentrations. The films contain relatively high concentrations of iron, chromium, nickel, oxygen and fluorine species distributed throughout the film thicknesses. The fluoride species can be removed by post-annealing in air, which improves the chemical stability of the films without damaging the nanoporous morphology of the remaining oxide.
► Self-organized nanoporous anodic films were formed on stainless steel. ► The films grew by the reduction of H2O content in the ethylene glycol electrolytes. ► Post-annealing converted water-soluble oxyfluoride to insoluble oxide.
Aim
In 2005, we changed our minimally invasive departmental policy for infants born before 26 weeks of gestation to a proactive approach. This included structured guidelines as well as intubation and ...surfactant in the delivery room, if the parents agreed. The aim of this study was to evaluate the effect of this change of policy.
Method
We compared the Ages and Stages Questionnaire (ASQ) scores, mortality rates and use of mechanical ventilation before (1999–2003) and after (2005–2011) the introduction of the new policy.
Results
Twenty‐two per cent of 61 infants in the before group had an ASQ z‐score of <−2 standard deviation at 18 months' corrected age, compared with 26% of 55 infants in the after group. Mortality decreased from 46% to 36% (p = 0.06) and the use of mechanical ventilation at any time during admission increased from 64% to 87% (p < 0.0001).
Conclusion
We demonstrated that changing our policy to a proactive approach to the initial care of infants born before 26 weeks did not result in a major increase in psychomotor deficit. However, the use of mechanical ventilation increased significantly and survival tended to improve.
Recycling of organic wastes within agriculture may help maintain soil fertility via effects on physical, chemical and biological properties. Efficient use, however, requires an individual assessment ...of waste products, and effects should be compared with natural variations due to climate and soil type. An 11-month incubation experiment was conducted between April 1998 and March 1999, in which a sandy loam without or with anerobically digested sewage sludge (4.2
t
dry
matter
(DM)
ha
−1) or household compost (17
t
DM
ha
−1) was incubated under constant laboratory conditions at 10
°C, as well as in the field. The following properties were monitored: wet-stability of soil aggregates, clay dispersibility, hot-water extractable carbohydrates, resin-extractable P
i, inorganic N, biomass C and N, PLFA profiles, FDA hydrolysis activity, β-glucosidase activity and CO
2 evolution. In general, effects of waste amendment were positive, but moderate compared to the dynamics observed in unamended soil, and mainly occurred in the first several weeks after amendment. The temporal dynamics of inorganic N, FDA hydrolysis activity, biomass C and PLFA composition appeared to be faster under the fluctuating climatic conditions in the field. To evaluate accumulated effects of repeated waste applications, soil was also sampled from a field trial, in which the sewage sludge and household compost had been applied at the same rates as in the incubation study for three consecutive years. Sampling took place after the final harvest, i.e. 5 months after the final waste application. Compost amendment had increased potentially mineralizable N by a factor of 1.8, and sludge amendment had increased the amount of resin-extractable P
i by a factor of 1.6. However, there were no accumulated effects of waste amendment on the fraction of soil in wet-stable aggregates, or on the microbiological properties tested, which supported the observation from the incubation study that effects of organic wastes were transient.
Experimental data for fluoranthene and feeding selectivity in combination with reaction‐diffusion modeling suggest that ingestion of contaminated sediment may often be the dominant uptake pathway for ...deposit‐feeding invertebrates in sediments. A dietary absorption efficiency of 56% and accompanying forage ratio of 2.4 were measured using natural sediment that had been dual‐labeled (14C:51Cr) with fluoranthene and fed to the marine deposit‐feeding polychaete Capitella species I. Only 3 to 4% of the total absorption could be accounted for by desorption during gut passage. These data were then used as input into a reaction‐diffusion model to calculate the importance of uptake from ingested sediment relative to pore‐water exposure. The calculations predict a fluoranthene dietary uptake flux that is 20 to 30 times greater than that due to pore water. Factors that act to modify or control the formation of local chemical gradients, boundary layers, or dietary absorption rates including particle selection or burrow construction will be important in determining the relative importance of potential exposure pathways. From a chemical perspective, the kinetics of the adsorption and desorption process are especially important as they will strongly influence the boundary layer immediately surrounding burrowing animals or irrigated tubes. The most important biological factors likely include irrigation behavior and burrow density and size.
The study focuses on the interfacial mass transfer from single CO2 bubbles with initial diameter in the range of 0.7−3.0 mm in a vertical column with stagnant deionized water. The objective is to ...enhance the understanding of the intricate phenomena involved in interfacial mass transfer by examining the individual effects of the liquid-side mass transfer coefficient and the bubble size. The liquid-side mass transfer coefficient is found in this study to be influenced by both the initial bubble diameter and on the bubble age, i.e., the time the bubble is exposed to the liquid influences the obtained liquid-side mass transfer coefficient. Existing literature suggests that bubbles of diameter <2−3 mm behave as rigid spheres with immobile interface and reduced internal gas circulation, which negatively impact the interfacial mass transfer. The results obtained from this study show that the maximum value of the liquid-side mass transfer coefficient is obtained for bubbles of diameter 2.1−2.3 mm. For bubbles with a mean diameter ≤1.4 mm, the mean liquid-side mass transfer coefficient decreases with decreasing mean bubble diameter. A Lagrangian model description is used with various correlations for the liquid-side mass transfer coefficients to perform numerical simulations of the change in bubble volume during the bubble rise. The existing correlations for the liquid-side mass transfer coefficient give very different simulation results and fail to accurately capture the transient evolution of the bubble as it exposes to the mass transfer phenomenon and hydrostatic pressure gradient. The correlation for the liquid-side mass transfer coefficient proposed by Clift et al. (1978) is modified in this work, and the experimentally obtained data are well predicted by the new modified correlation.
•Investigation of kL for single CO2 bubbles in stagnant water.•kL depends on both the initial bubble diameter and bubble-liquid exposure time.•Maximum kL is obtained for bubbles with initial diameter in the range of 2.1-2.3 mm.•Existing kL-correlations implemented in a Lagrangian model fail to accurately predict the change in Vb with time.
The central nervous system (CNS) of 221 adults and 31 infants or children with the acquired immunodeficiency syndrome (AIDS) was examined with immunocytochemistry for infectious agents and for human ...immunodeficiency virus-1 (HIV-1) antigen (gp41). Since the major risk factor in this population was intravenous drug abuse, there were more female and pediatric patients than in other neuropathology autopsy series. Although children had a different spectrum of pathologic changes, including less frequent opportunistic infections, women did not differ from men in terms of types or incidence of opportunistic infections, vascular disease, neoplasia, and subacute AIDS encephalitis (SAE). Subacute AIDS encephalitis was detected in 26% of adult and 48% of pediatric brains. Immunocytochemical analysis of 100 adult and 20 pediatric brains revealed gp41 immunoreactivity in 78% and 40%, respectively. Virtually all adult brains with SAE had gp41 immunoreactivity in macrophages and microglia. Even brains with no significant pathology had frequent gp41 immunoreactivity, especially in the basal ganglia. In pediatric brains, including cases with SAE, gp41 immunoreactivity was less abundant, suggesting the possibility of latent infection or viral clearance. Spinal cords with vacuolar myelopathy or corticospinal tract degeneration had only rare gp41-positive cells. Brains from 16 aborted fetuses from HIV-1-seropositive women were all negative for gp41 immunoreactivity, but 12 brains were positive for HIV-1 by the polymerase chain reaction. These results may indicate that HIV-1 infection in fetal brains is below the limits of detection of immunocytochemistry. The differences noted between adults and children suggest that adults more often have productive CNS HIV-1 infection.
The mass transfer of gas–liquid systems is commonly reported through the volumetric mass transfer coefficient, kLa, which is a function of several complex phenomena. To optimize the rate of mass ...transfer, increased knowledge about the individual effects of the interfacial area, a, and the liquid-side mass transfer coefficient, kL, on kLa is necessary. In this study, kLa was measured by monitoring the dissolved oxygen concentration in a bubble column. The bubble flows were recorded by a photographic method and the images were analyzed by means of artificial neural network to determine the bubble size. The effects of rheology, superficial gas velocity, and gas sparger design were analyzed. kL decreased with an increase in the superficial gas velocity and with an increase in the viscosity. The relative change in a was much larger compared to the relative change in kL, and hence, for the investigated operational conditions and liquid solutions, the change in kLa was mainly attributed to the change in a. Bubble clusters were formed in the non-Newtonian solutions but for the given operating conditions and liquid solutions, the bubble cluster formation did not have a prominent effect on the mass transfer.
•Investigation of kLa, kL, and a in Newtonian and non-Newtonian solutions.•The effects of rheology, superficial gas velocity, and gas sparger design on the mass transfer and bubble hydrodynamics.•The change in kLa is manly attributed to the change in a.•Bubble clusters did not have a prominent effect on the mass transfer.•At a given us, kL was independent of db in water, whereas kL increased with db in viscous systems.
In conclusion, there is overwhelming evidence that within the CNS the primary sites of active HIV-1 infection are microglia. CNS infection may be related to the normal repopulation of the CNS by ...monocytes (microglial turnover) that carry latent infection into the CNS. Activation of viral infection may depend upon microglial differentiation, soluble factors (cytokines), and/or coexistent infections. Infection of microglia may disturb the normal hemostatic balance that exists between microglia and other glia, and between microglia and neurons, processes that are only recently being explored at the molecular level. The impact that HIV infection of microglia may have on synaptic integrity is unknown. Cytokines appear to be prime candidates as mediators of some of the adverse effects of microglial infection on other CNS cells, myelin and endothelial cells.
Background: Although non-incisional surgery to create a supratarsal fold (double eyelid) is preferred by Japanese patients, current procedures are either technically complex or do not produce lasting ...results.
Objective: We describe a new, non-incisional technique that makes use of double-armed sutures and twists to create double eyelids in Asian patients.
Methods: After everting the upper eyelid, a double-armed suture needle is passed from the conjunctival surface through the tarsal plate and then to the skin surface. The other end of the suture is advanced about 3 to 5 mm and also brought out through the tarsal plate. A second suture is used to create another U-stitch adjacent to the first suture. The upper eyelid is returned to its original position, and the sutures from the central hole are twisted around each other 4 or 5 times. They are then passed under the skin, one medially and one laterally, and the lateral and medial sutures are tied.
Results: The authors have performed 1108 procedures during the past 10 years with no loss of double-eyelid line in a mean follow-up time of 32 months.
Conclusions: The double suture and twist technique for creating double eyelids in Asian patients is simple, reproducible, durable, and safe. (
Aesthetic Surg J 2001;21:227-232.)
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