The effect of feeding rosemary, oregano, saffron and &#945-tocopheryl acetate on hen performance and oxidative stability of eggs

In this study the effects of feeding rosemary, oregano, saffron and α-tocopheryl acetate on hen performance and egg quality were investigated. One hundred-twenty Lohmann laying hens, 32 weeks old, were divided into five groups replicated four times with six hens per replicate. One group was given a basal diet and served as control (CON). The experimental diets given to the other four groups were based on the basal diet but contained an additional 200 mg α-tocopheryl acetate/kg (TOC), or rosemary at 5 g/kg diet (ROS), oregano at 5 g/kg diet (ORE) or saffron at 20 mg/kg diet (SAF). At the end of the feeding trial that lasted 56 days, hen performance and some egg quality characteristics were determined, whereas the oxidative stability of the refrigerated stored shell eggs and liquid yolks were also examined. Results showed no significant differences in egg production, feed intake, feed conversion ratio, egg weight and shape, yolk shape, Haugh units and shell thickness among treatments. However, yolk colour was significantly improved in the SAF group compared to all other groups. The extent of lipid oxidation in shell eggs differed among the dietary treatments, but did not change with storage time. In liquid yolk at pH 6.2, lipid oxidation was higher in the CON group compared to all other groups. The ORE group presented lower oxidation rate than the ROS group, but higher than the SAF group, which in turn exhibited higher oxidation rate than the TOC group. When liquid yolk was acidified to pH 4.2, the lipid oxidation profile remained unchanged but the rate was much more intense. Keywords: Rosemary; oregano; saffron; α-tocopherol acetate;egg quality; hen performance; oxidative stability South African Journal of Animal Sciences Vol. 35 (3) 2005: pp.143-15

Design, manufacture and testing of capacitive pressure sensors for low-pressure measurement ranges

This article presents the design, manufacture and testing of a capacitive pressure sensor with a high, tunable performance to low compressive loads (<10 kPa) and a resolution of less than 0.5 kPa. Such a performance is required for the monitoring of treatment efficacy delivered by compression garments to treat or prevent medical conditions such as deep vein thrombosis, leg ulcers, varicose veins or hypertrophic scars. Current commercial sensors used in such medical applications have been found to be either impractical, costly or of insufficient resolution. A microstructured elastomer film of a polydimethylsiloxane (PDMS) blend with a tunable Young’s modulus was used as the force-sensing dielectric medium. The resulting 18 mm × 18 mm parallel-plate capacitive pressure sensor was characterised in the range of 0.8 to 6.5 kPa. The microstructuring of the surface morphology of the elastomer film combined with the tuning of the Young’s modulus of the PDMS blend is demonstrated to enhance the sensor performance achieving a 0.25 kPa pressure resolution and a 10 pF capacitive change under 6.5 kPa compressive load. The resulting sensor holds good potential for the targeted medical application

Nanocomposite-based microstructured piezoresistive pressure sensors for low-pressure measurement range

Piezoresistive pressure sensors capable of detecting ranges of low compressive stresses have been successfully fabricated and characterised. The 5.5 × 5 × 1.6 mm3 sensors consist of a planar aluminium top electrode and a microstructured bottom electrode containing a two-by-two array of truncated pyramids with a piezoresistive composite layer sandwiched in-between. The responses of two different piezocomposite materials, a Multiwalled Carbon Nanotube (MWCNT)-elastomer composite and a Quantum Tunneling Composite (QTC), have been characterised as a function of applied pressure and effective contact area. The MWCNT piezoresistive composite-based sensor was able to detect pressures as low as 200 kPa. The QTC-based sensor was capable of detecting pressures as low as 50 kPa depending on the contact area of the bottom electrode. Such sensors could find useful applications requiring the detection of small compressive loads such as those encountered in haptic sensing or robotics

Antimicrobial de-escalation in the critically ill patient and assessment of clinical cure: the DIANA study

Purpose: The DIANA study aimed to evaluate how often antimicrobial de-escalation (ADE) of empirical treatment is performed in the intensive care unit (ICU) and to estimate the effect of ADE on clinical cure on day 7 following treatment initiation. Methods: Adult ICU patients receiving empirical antimicrobial therapy for bacterial infection were studied in a prospective observational study from October 2016 until May 2018. ADE was defined as (1) discontinuation of an antimicrobial in case of empirical combination therapy or (2) replacement of an antimicrobial with the intention to narrow the antimicrobial spectrum, within the first 3 days of therapy. Inverse probability (IP) weighting was used to account for time-varying confounding when estimating the effect of ADE on clinical cure. Results: Overall, 1495 patients from 152 ICUs in 28 countries were studied. Combination therapy was prescribed in 50%, and carbapenems were prescribed in 26% of patients. Empirical therapy underwent ADE, no change and change other than ADE within the first 3 days in 16%, 63% and 22%, respectively. Unadjusted mortality at day 28 was 15.8% in the ADE cohort and 19.4% in patients with no change [p = 0.27; RR 0.83 (95% CI 0.60\u20131.14)]. The IP-weighted relative risk estimate for clinical cure comparing ADE with no-ADE patients (no change or change other than ADE) was 1.37 (95% CI 1.14\u20131.64). Conclusion: ADE was infrequently applied in critically ill-infected patients. The observational effect estimate on clinical cure suggested no deleterious impact of ADE compared to no-ADE. However, residual confounding is likely

Dependence of Olive Morphogenesis on Callus Origin and Age

Calli of 0, 7, 14 and 21 days from radicles and cotyledonary segments of mature olive zygotic embryos were tested for rhizogenesis and somatic embryogenesis. Explants were cultured in OMc plus 2.5 μM 2iP and 25.0 μM IBA, and rhizogenesis during this 21-day-long period was recorded. Tests (subcultures) were realized in OMc without exogenous growth regulators or in OMc plus 2.5 μM IBA for 2 months. A decreasing rhizogenic gradient from radicles to distal cotyledon segments and, at least in some cases, an increase in rhizogenesis with callus age were found. Rhizogenesis is manifested after 2 weeks and reaches a maximum level in less than 50 days from inoculation. Somatic embryogenesis is manifested after 30–35 days and is maximum after 75 days from inoculation. High somatic embryogenesis (up to 40%) was observed in calli from radicles. Low embryogenesis occurs in calli from both cotyledonary segments. Older calli (14- and 21-day-old) give higher somatic embryogenesis than the younger ones (7-day-old), while in zero-day-old calli and during the 21-day-long callus formation period, somatic embryogenesis was nil. © 1992, Gustav Fischer Verlag, Stuttgart. All rights reserved

Studies on the development of the air pores and air chambers of Marchantia paleacea: 1. Light microscopy

The ontogeny of the air pores and air chambers of Marchantia paleacea begins with the schizogenous development of protodermal intercellular spaces of the initial apertures, and is completed with the formation of the air pores and giant sub-epidermal air chambers bearing numerous photosynthetic filaments. Intercellular space formation commences from the thallus surface and proceeds inwards to the first internal layer of cells. The cells among which spaces develop do not originate from one mother cell. Spaces are formed only in the regions of the intersection of the anticlinal walls of three, four, or sometimes more successive derivatives of S1, S3 and S4 segments of the apical cell, one or two of which have been divided periclinally and the rest anticlinally. Protodermal intercellular spaces appear in most or all the corners of these cells, the anticlinal walls of which exhibit an opposite disposition. The S1, S2, S3 and S4 segments are produced by definite divisions of a five-sided apical cell and by a series of divisions give rise to initial cells of the internal layers of the thallus and initial cells of the protodermal and sub-protodermal layers. The concept of a quiescent apical cell cannot be accepted, since dividing apical cells have been observed, and the pattern of wall disposition of the thallus apex cannot be explained without the active participation of the apical cell.The air chambers are apparently of exogenous origin. They result from the broadening of the bottom of the initial apertures by the coordination of the rate of anticlinal divisions and growth of the protodermal and sub-protodermal cells surrounding the intercellular spaces of the initial apertures. The ontogeny of the pore rings starts at an advanced stage of air chamber formation not from a mother cell but from the cells which surround the closed entrance of the air chamber, by a shift of the plane of division from anticlinal to periclinal. Before the periclinal divisions a new axis of growth perpendicular to the thallus surface is established in the mother cells of the pore.By a polarized growth into the air chamber followed by periclinal divisions, the cells of the floor form initial cells of the photosynthetic filaments. The latter divide again to form single or branched photosynthetic filaments. © 1982 Annals of Botany Company