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Kolomela Mine, formerly known as the Sishen South Project, is located approximately 9 km from Postmasburg, in the Northern Cape Province of South Africa. Iron ore is primarily concentrated near the top of the Asbesheuwels or Asbestos Hills Subgroup, within the Kuruman Formation. High-grade, hematite-rich, iron-ore deposits in South Africa have been addressed in the literature, although much of this work focusses on their geochemical or isotopic signatures and the role of paleosinkholes in ore preservation. Recent work on high-grade, BIF-hosted Fe deposits, in South Africa and elsewhere, emphasizes the role of deformation in iron mineralisation and upgrading of BIF over a sequence of events, either punctuated by supergene enrichment or terminating with a supergene overprint. The proximity of the Kheis orogenic front, the protracted tectonic history of the area, a recently-resolved local structural framework and an emerging set of literature on superimposed hypogene, metasomatic, hydrothermal, hypothermal and deformation-induced processes, justify a re-examination of the Kolomela deposits. Closely-spaced drillhole data, pit mapping over a period of four years and re-interpretation of the tectonic setting from high-resolution geophysical data, have been incorporated into fully-constrained 3D models of the five principle Kolomela deposits, which are presented here and analysed in terms of their geometry, tectonic setting, relationship to major structures, the geometry of the underlying dolomite contact and the possible role of gabbroic intrusions. A strong spatial correlation between thicker ore and thicker, underlying gabbroic bodies, in the forms of sills, is evident. We propose that protracted, multi-phase tectonic evolution, complete with several compressional-extensional events at this margin of the Kaapvaal Craton provided an ideal setting for “preparation” of BIF by early low-grade metamorphism, deformation and porosity creation, followed by fluid movement along interconnected contacts, unconformities, gabbro contacts and major structures.

In this paper we present and discus the structural, elastic, electronic and optical properties of the new ternary alloys Ca0.75Zn0.25S and Ca0.75Zn0.25Se in NaCl (B1) structure using the full potential-linearized augmented plane wave (FP-LAPW) method which is based on the density functional theory (DFT). To perform the structural and elastic calculations, we have used the Wu-Cohen generalized gradient approximation (WC-GGA) as exchange-correlation potential while for the electronic and optical properties, Tran-Blaha modified Becke-Johnson(TB-mBJ) scheme is employed. The study is focused on the variation of a number of properties of binary compounds CaS and CaSe when they are doped with 25% of zinc (Zn). For binary compounds, a good agreement is obtained for most of the properties calculated in this work and those measured experimentally. This study is the first prediction of the structural, elastic electronic and optical properties of ternary alloys Ca0.75Zn0.25S and Ca0.75Zn0.25Se. Both these ternary alloys are mechanically stable and present a semiconducting behavior with a direct band gap contrary to the parent binary compounds CaS and CaSe which have an indirect band gap. Therefore, fast and efficient optoelectronic devices might be manufactured by these new ternary alloys.

Background Starch contributes to barley grain and malt quality which in turn contributes to beer quality and flavour; through fermentable sugar profiles, rates of fermentation and Mallard reactions. Both amylopectin and amylose are enzymatically degraded to release maltose, maltotriose and higher order sugars. Scope and approach Amylopectin is highly branched [α-(1 → 6) glycoside bond branch points] with numerous short branches while amylose is a long chained polymer with a few side branches. During grain development, the final level of branching is controlled by two enzymes namely; isoamylase and limit dextrinase (LD). Mutations in either of these genes can also result in changes to structure, content, and granule formation and size. During the malting free LD will to cleave the α-(1 → 6) bonds but during mashing processes, bound LD is release, resulting in chains of various length available for other starch degrading enzymes to hydrolyse. Findings and conclusions While there is a good understanding of most of the individual aspects in amylopectin formation, structure and degradation; the story remains incomplete, as most of this understanding has been gained from experiments with only a limited number of barley varieties, limitations in the technology for structural measurement, and since no data is available to link structure to fermentable sugar profiles.

The objective of this work is to predict the structural, electronic, magnetic and elastic properties of Mg 1−x TM x S (TM=Mn, Fe, Co and Ni) compound in the zinc blende Ferromagnetic phase using first principal approach. The structural and elastic properties are performed using the generalized gradient approximation proposed by Wu and Cohen(WC-GGA). However, the electronic and magnetic properties have been performed using modified Becke-Johnson potential combined with the LDA correlation (mBJLDA). The results show that all compounds Mg 1−x Mn x S, Mg 1−x Fe x S and Mg 1−x Ni x S exhibit a half-metallic ferromagnetic character with 100% spin-polarization at the Fermi level, except Mg 1−x Co x S is a metal. For each compounds study here, the total magnetic momentum is an integer equal to magnetic moments of TM atom in their free space charge value. Due to the p–d hybridization, there is a small local magnetic moment on the Mg and S sites; whereas, the local magnetic moments of TM atom reduce from their free space charge value. In addition, we investigate the mechanical behavior of MgS and Mg 1−x TM x S; all compounds studied here are mechanically stable and exhibit a strong anisotropic behavior.

The interaction between dietary balanced protein, ractopamine (RAC) and Improvac (IMP) on the growth response of 120 individually penned male PICC pigs was evaluated. The pigs entered the trial at 16 weeks of age and were assigned to 12 treatments using a 2×2×3 factorial design. Three balanced protein diets, formulated with standard illeal digestible lysine levels of 7.50 (low), 9.79 (medium) and 12.07 g/kg (high), were fed from 20 weeks. Improvac was administered at 16 and 20 weeks, the booster being given 4 weeks before slaughter. Ractopamine was supplemented at 10 mg/kg to the applicable treatments from 20 weeks. Live weight, backfat depth and food intake were measured on a weekly basis. Primary vaccination had no influence on the parameters measured. Immunocastration, RAC and higher protein diet treatments increased weight gain, but food intake was increased only with the use of IMP. Although weight gain increased in IMP-treated males, the increased feed intake resulted in their feed conversion efficiencies (FCE) being inferior to the intact controls. Feeding RAC only benefitted FCE when a high or medium protein diet was fed. Immunocastrates deposited more backfat after the booster vaccination than did entire males. Thus the cost of using RAC, IMP and of increasing dietary protein content needs to be weighed up against the additional revenue generated through the use of these interventions.

Background: We compared cognitive outcomes at weeks 0, 48, and 96 for HIV-infected (HIV+), HIV-exposed uninfected (HEU), and HIV-unexposed (HUU) cohorts of children at 6 sub-Saharan sites. Methods: IMPAACT P1060 compared Nevirapine (NVP) versus Lopinavir/Ritonavir (LPV/r)-based ARV in children (HIV+) 6 to 35 months of age, were later enrolled for neurocognitive follow-up at 5 to 11 yrs of age. 611 (246 HIV+, 183 HEU, 182 HUU) of the 615 enrolled at 6 sites (South Africa [3], Zimbabwe, Malawi, Uganda), were compared across 3 assessment time points (weeks 0, 48, 96). 603 children completed week 48 and 588 completed week 96 visits. They were tested with the Kaufman Assessment Battery for Children, 2nd ed. (KABC-II) cognitive ability, Tests of Variables of Attention (TOVA) attention/impulsivity, Bruininks-Oseretsky Test of Motor Proficiency (BOT-2), and parental Behavior Rating Inventory of Executive Function (BRIEF). Cohorts were compared using linear mixed models adjusted for site, child's age and gender. Findings: Comparisons among cohorts were consistent across time points for most outcomes, with the HIV cohort significantly worse than the HEU and HUU cohorts for all KABC-II, TOVA, BOT-2 global outcomes (p7 years based on country regulations.

Poultry nutritionists should constantly evaluate their feeds and feeding programs in view of the changes that continue to be made to the potential growth rate of broilers and egg production in laying hens with the objective of providing the birds with the optimum economic level of nutrients at all times. In this review, the models generated at Universidade Estadual Paulista (UNESP) Jaboticabal, to estimate the optimum intake of amino acids (AA) for broilers and laying hens are presented. These models were used to estimate the variation in AA intake within a broiler population making use of coefficients of variation that represent the real situation in a commercial broiler operation. The range of AA intakes obtained was compared to some commonly applied feeding programs and recommendations. Based on results of our developed models and other feeding programs, feeds were formulated and growth was predicted using a growth simulation model (Avinesp). The prediction of growth showed that these models are reliable and useful tools to assist the nutritionists in decision making. In a study with laying hens, the Reading model (RM) was used to establish optimum economic AA intakes in a flock of hens. The input variables were the means and standard deviations of egg output and BW, and the relationship between the marginal cost of the AA and the marginal revenue for eggs. Based on this model, the optimum intake of each AA can vary with each of the variables considered. The models proposed in our study enable important decisions to be made regarding AA intakes to be used to obtain optimum economic performance from a population of broilers and laying hens.

Backcross breeding is the most commonly used method for incorporating a blast resistance gene into a rice cultivar. Linkage between the resistance gene and undesirable units can persist for many generations of backcrossing. Marker-assisted backcrossing (MABC) along with marker-assisted selection (MAS) contributes immensely to overcome the main limitation of the conventional breeding and accelerates recurrent parent genome (RPG) recovery. The MABC approach was employed to incorporate (a) blast resistance gene(s) from the donor parent Pongsu Seribu 1, the blast-resistant local variety in Malaysia, into the genetic background of MR219, a popular high-yielding rice variety that is blast susceptible, to develop a blast-resistant MR219 improved variety. In this perspective, the recurrent parent genome recovery was analyzed in early generations of backcrossing using simple sequence repeat (SSR) markers. Out of 375 SSR markers, 70 markers were found polymorphic between the parents, and these markers were used to evaluate the plants in subsequent generations. Background analysis revealed that the extent of RPG recovery ranged from 75.40% to 91.3% and from 80.40% to 96.70% in BC1F1 and BC2F1 generations, respectively. In this study, the recurrent parent genome content in the selected BC2F2 lines ranged from 92.7% to 97.7%. The average proportion of the recurrent parent in the selected improved line was 95.98%. MAS allowed identification of the plants that are more similar to the recurrent parent for the loci evaluated in backcross generations. The application of MAS with the MABC breeding program accelerated the recovery of the RP genome, reducing the number of generations and the time for incorporating resistance against rice blast.

Purpose: To evaluate the safety and efficacy of dexamethasone intravitreal implant (Ozurdex, DEX implant) 0.7 and 0.35 mg in the treatment of patients with diabetic macular edema (DME).Design: Two randomized, multicenter, masked, sham-controlled, phase III clinical trials with identical protocols were conducted. Data were pooled for analysis.Participants: Patients (n = 1048) with DME, best-corrected visual acuity (BCVA) of 20/50 to 20/200 Snellen equivalent, and central retinal thickness (CRT) of ≥300 μm by optical coherence tomography.Methods: Patients were randomized in a 1:1:1 ratio to study treatment with DEX implant 0.7 mg, DEX implant 0.35 mg, or sham procedure and followed for 3 years (or 39 months for patients treated at month 36) at ≤40 scheduled visits. Patients who met retreatment eligibility criteria could be retreated no more often than every 6 months.Main Outcome Measures: The predefined primary efficacy endpoint for the United States Food and Drug Administration was achievement of ≥15-letter improvement in BCVA from baseline at study end. Safety measures included adverse events and intraocular pressure (IOP).Results: Mean number of treatments received over 3 years was 4.1, 4.4, and 3.3 with DEX implant 0.7 mg, DEX implant 0.35 mg, and sham, respectively. The percentage of patients with ≥15-letter improvement in BCVA from baseline at study end was greater with DEX implant 0.7 mg (22.2%) and DEX implant 0.35 mg (18.4%) than sham (12.0%; P ≤ 0.018). Mean average reduction in CRT from baseline was greater with DEX implant 0.7 mg (−111.6 μm) and DEX implant 0.35 mg (−107.9 μm) than sham (−41.9 μm; P < 0.001). Rates of cataract-related adverse events in phakic eyes were 67.9%, 64.1%, and 20.4% in the DEX implant 0.7 mg, DEX implant 0.35 mg, and sham groups, respectively. Increases in IOP were usually controlled with medication or no therapy; only 2 patients (0.6%) in the DEX implant 0.7 mg group and 1 (0.3%) in the DEX implant 0.35 mg group required trabeculectomy.Conclusions: The DEX implant 0.7 mg and 0.35 mg met the primary efficacy endpoint for improvement in BCVA. The safety profile was acceptable and consistent with previous reports.

The identification of "stay-green" in sorghum and its positive correlation with yield increases has encouraged attempts to incorporate "stay-green"-like traits into the genomes of other commercially important cereal crops. However, knowledge on the effects of "stay-green" expression on grain quality under extreme physiological stress is limited. This study examines impacts of "stay-green"-like expression on starch biosynthesis in barley (Hordeum vulgare L.) grain under mild, severe, and acute water stress conditions induced at anthesis. The proportions of long amylopectin branches and amylose branches in the grain of Flagship (a cultivar without "stay-green"-like characteristics) were higher at low water stress, suggesting that water stress affects starch biosynthesis in grain, probably due to early termination of grain fill. The changes in long branches can affect starch properties, such as the rates of enzymatic degradation, and hence its nutritional value. By contrast, grain from the "stay-green"-like cultivar (ND24260) did not show variation in starch molecular structure under the different water stress levels. The results indicate that the cultivar with "stay-green"-like traits has a greater potential to maintain starch biosynthesis and quality in grain during drought conditions, making the "stay-green"-like traits potentially useful in ensuring food security. (C) 2013 Elsevier Ltd. All rights reserved.

We report a simple, novel and low-cost method for the synthesis of aragonite nanoparticles from cockle shells. Aragonite is one of the least abundant biogenic polymorphs of calcium carbonate and is widely used as a biomaterial for the repair of fractured bone, development of advanced drug delivery systems, and tissue scaffolds. The method involves a simple mechanical grinding of the micron-sized cockle shell powders in the presence of a non-toxic and non-hazardous biomineralization catalyst, dodecyl dimethyl betaine (BS-12). The method produces rod-shaped aragonite particles with a diameter of 20 ± 5 nm with good reproducibility and without any additional impurities. This was confirmed by a combined analysis of variable pressure scanning electron microscopy (VPSEM), transmission electron microscopy (TEM), Fourier transmission infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA), X-ray diffraction spectroscopy (XRD) and energy dispersive X-ray analyser (EDX). The method should find potential applications in industry for the large scale synthesis of aragonite nanoparticles from a low cost but abundant natural resource such as cockle shells.

Traditionally the tuning of dynamic matrix control (DMC) type multivariable controllers is done by trial and error. The APC engineer chooses arbitrary starting values and tests the performance on a simulated controller. The engineer then either increases the values to suppress movement more, or decreases them to have the manipulated variables move faster. When the controller performs acceptably in simulation, then the tuning is improved during the commissioning of the controller on the plant. This is a time consuming and unscientific exercise and therefore often does not get the required attention. This leads to unacceptable controller behaviour during commissioning and sub-optimal control once commissioning is completed. This paper presents a new method to obtain move suppression factors for DMC type multivariable controllers by using a Nelder Mead search algorithm to find move suppressions that will provide acceptable control behaviour. Acceptable behaviour is described by characterising the dynamic move plan calculated by the controller for each of the manipulated variables.

Point-of-care testing for β-hCG has been widely advocated to allow rapid diagnosis/exclusion of pregnancy in the emergency department. A quantitative blood β-hCG assay has the additional benefit of being able to monitor the viability of pregnancy, using serial measurements, to determine the appropriate expected increase in β-hCG levels over time (e.g. ectopic pregnancy), and aiding in determining if an intrauterine gestational sac should be visible on sonographic imaging. Objectives Evaluation of the newly released Abbott i-STAT β-hCG point-of-care assay with the Beckman Coulter β-hCG laboratory assay in use. Design and methods Whole blood, plasma and serum samples with a wide range of β-hCG concentrations were analysed by both methods. Results The Abbott I-STAT β-hCG compares favourably, can be performed on heparinised whole blood, plasma and serum, and shows acceptable accuracy and precision. However a hook effect at elevated β-hCG was shown in gestational trophoblastic disease as well as normal pregnancies. Conclusions The i-STAT β-hCG performs acceptably in its intended use in the early detection of pregnancy, but results should always be interpreted within the clinical context, as a hook effect may occur.

Geneticists have been highly successful in improving potential growth of broilers over the past 50 years, and it is likely that more genetic progress is possible. However, in order to maximise this potential it will be necessary for nutritionists to review the way in which these fast-growing strains are fed. Unless changes are made to the composition of broiler feeds in the future, constraints are likely to occur immediately after hatching, when gut capacity will not allow the consumption of sufficient of a conventional starter feed to enable the chick to grow at its potential, and towards the end of the growing period, when heat production is so high that it may be impossible for a broiler to lose sufficient heat to the environment to enable it to grow at its potential. Issues discussed are those concerning the constraining effect of the egg on embryonic development, early feeding of the embryo and chick, problems associated with meeting the amino acid requirements immediately post-hatch, and various nutritional interventions that have been suggested as methods of reducing the heat load on broilers. It is suggested that with some manipulation of feed nutrient contents nutritionists will be able to keep up with the genetic changes taking place into the near future, but that the constraining effect on growth of global warming is a challenge that will need to be addressed by biologists and engineers in poultry research.

SUMMARY Amino acid content of the defeathered broiler carcass at different ages may provide needed information for meeting nutritional requirements. Both sexes of 2 strain-crosses were reared on corn- and soybean meal-based diets exceeding the minimum nutrient recommendations. Defeathered carcasses from the heaviest and lightest birds per pen were individually ground and amino acid (AA) content was determined. Broiler age played a greater role than either sex or strain for influencing individual, total essential, and total nonessential AA contents. Certain of the essential and nonessential AA were influenced differentially by broiler age and sex. Total nonessential AA, as a percentage of total essential AA, were influenced by broiler age and sex in a similar manner. The influence of age on carcass AA content is considered to reflect compositional changes occurring in response to growth. Despite selection differences in body fat content between the 2 broiler strain-crosses, carcass AA content, expressed as a percentage of carcass protein, was not affected by this, suggesting genetic selection does not have a major influence on carcass AA contents. If this is true, then future improvements in broiler production parameters would require only that carcass protein content be analyzed to determine carcass AA content. Analyzing the carcass for protein would be quicker and less expensive than analyzing for AA.

A multiple coal fired boiler house provides steam for utility usage in various production plants. Maintaining stable header pressure and boiler availability is of critical importance for downstream consumers. Advanced Process Control comprising of a G2 based expert system and Model Predictive Control was implemented to improve the boiler house performance. The results yielded improvements in the main header pressure stability, reduction in boiler saturation and significant saving in coal consumption.

An advanced process control (APC) system using G2 and AspenTech's DMCplus controller was implemented on Anglo Platinum's Precious metals refinery. The APC was implemented on a batch reactor where an exothermic reaction occurred. The APC controller was able to counter the effects of an integrating process model and long time delay to improve overall stability of the reactor. The APC controller resulted in improved temperature stability, reduction in total batch time and reduction in a regent consumption.

Monitoring and predicting growth and feed intake of cultured aquatic animals is a significant problem in aquaculture. The present study examines the potential of an approach based on potential accretion rate of body protein to predict live weight gain and feed requirement of the marine prawn, Fenneropenaeus indicus. The protein accretion rate was predicted using the Gompertz equation while the growth of body components and nutrient gains therein was established using allometric relationships. Live weight gain was determined by summing the accretion rates of body protein, lipid, water, ash and carbohydrate. The model parameters included the protein content at maturity (Pdm, [mg]), the rate of maturing (β, [/d]), the maximum rate of protein deposition (Pdmax, [mg day− 1]), the lipid to protein ratio at maturity (LPRm, [Ldm:Pdm]), ash (APRm,[Adm:Pdm]), water (WAPRm,[WAdm:Pdm]) and carbohydrate to protein ratio at maturity (CPRm,[Cdm:Pdm]), and the exoskeleton to flesh ratio (E:F). To generate information to establish these parameters, feeding trials with prawn were carried out in indoor tanks and an outdoor growout pond. Juveniles from the same brood stock were allowed to grow to adults under conditions assumed ideal. Tank reared animals failed to obtain similar growth to those cultured in the pond. Values for the above parameters for a mixed batch of pond reared prawns were estimated to be 6541 mg, 0.014/d, 32.68 mg day− 1, 0.03, 0.20, 3.30, 0.06 and 1:3.6, respectively when reared at 19–27 °C and 21–27‰. Results indicated that the model proposed here, derived from and based on research in higher vertebrates, was well suited to describing the genotype of F. indicus reared under semi-intensive conditions. This study is, to our knowledge, the first to examine and describe mathematically the rates of body lipid, ash, water and carbohydrate accretion in prawns as a function of protein gains in the flesh and exoskeleton of F. indicus.

Summary We report a case of extensive necrogranulomatous pneumonia due to infection with the dassie bacillus ( Mycobacterium tuberculosis complex sp.) in a free-living pregnant adult female dassie (rock hyrax— Procavia capensis ). A juvenile female dassie from the same colony also showed a focal lesion in the lungs suggestive of mycobacterial pneumonia. Our findings indicate the widespread occurrence of the dassie bacillus in free-living dassies and suggest very high infection rates in some populations. The introduction of South African dassies into novel environments should be considered in this light.

The weevil Cleopus japonicus Wingelműller has been identified as a biological control agent for the highly invasive weed species Buddleia davidii . To study the potential effect of C. japonicus on the growth of this prolific plant, browsing was simulated on field grown plants over the course of a year, using four artificial defoliation levels (0, 33%, 66% and 100%). A simple process-based model was fitted to measurements to identify compensatory mechanisms induced by defoliation and to quantify their influence on above-ground plant biomass ( W p ) and the ratio of leaf to total biomass ( W l / W p ). The method outlined in this paper provides a framework for quantifying the net growth impact of feeding by folivorous biological control agents on weeds. This method also provides a means of understanding critical levels of defoliation needed to achieve target levels of weed suppression. Results showed relative values of W p for treatments in which 33%, 66% and 100% of leaf area had been removed, were 0.61, 0.44 and 0.08, respectively, compared to the undefoliated control. Defoliation intensity was positively related to light use efficiency ( e ), daily allocation of biomass to leaves ( γ ) and specific leaf area, and negatively related to rates of natural leaf loss. Model results show that defoliation induced increases in e and γ to be the most effective means of compensating for removed leaf area in the two treatments with highest levels of defoliation.

Predicting the response of poultry to nutrients has progressed to a stage where it is now not only possible to predict voluntary feed intake accurately, but broiler feeds and feeding programmes may now be optimised using the more advanced simulation models. Development of such prediction models has stimulated useful and purposeful research targeted at filling the gaps in our knowledge of critical aspects of the theory incorporated into these models. The aim of this paper was to review some of these past developments, discuss the controversy that exists in designing and interpreting response experiments, and highlight some of the most recent challenges related to the prediction of responses to nutrients by poultry. These latter include differences, brought about by selection for diverse goals, that have become apparent between modern broiler strains in their responses in feed intake and mortality, which are not independent of level of feeding or strain of broiler, as was previously believed. Uniformity, an important quality criterion in broiler processing, is also not independent of level of feeding, and the effect may now be predicted using stochastic models. It is not yet clear whether breast meat yield, the carcass component of broilers yielding the highest returns, is a function of the strain of broiler or simply that of the protein weight of the bird when processed. An important aspect of response prediction is dealing with constraints to performance: whereas it is relatively straightforward to simulate the potential performance of a broiler, such performance is often constrained by the physical, social and infectious environment, among others, providing a challenge to modellers attempting to predict actual performance. Some of these constraints to potential performance have not yet been adequately described, but are now receiving attention, suggesting that nutrient responses in poultry have the potential to be more accurately predicted in the future.

Growing pullets were maintained on 14-h photoperiods and given diets supplemented with 25 mg of melatonin (MEL)/kg during the final 7 h of the photo-period to investigate the role of MEL in sexual development. Melatonin diets were fed to 70 d (to mimic a transfer from 7 to 14 h at 70 d), from 105 d onward (to mimic a transfer from 14 to 7 h at 105 d), or throughout the trial (to mimic constant 7-h photoperiods). Control birds, which were fed normal diets, were maintained on 7 or 14 h, transferred from 7 to 14 h at 70 d, or transferred from 14 to 7 h at 105 d. The MEL groups matured 6 to 11 d later than the constant 14-h controls. The group mimicking a transfer from 7 to 14 h matured 35 d later than photostimulated controls, the group mimicking a 14 to 7-h change at 105 d matured 41 d earlier than birds given a decrease in day length; the third group matured 13 d earlier than constant 7-h controls. Although these data suggest that the birds did not perceive the final 7 h of the photoperiod as being part of the night, when given MEL diets, residual plasma MEL during the first 7 h of the photoperiod was atypically high, possibly preventing an interpretation of day and night. However, continuously high plasma MEL did not result in birds responding as if in constant darkness, because birds transferred from darkness to 14 h at 70 d would not have matured at a similar time to birds changed from 14 h to darkness at 105 d. Plasma LH concentrations for birds mimicking a 7 to 14 h change at 70 d were not significantly different from constant 7-h controls after the transfer to normal diets. The later maturity of the experimental groups, compared with constant 14-h controls, clearly indicated that MEL had some influence over hypothalamic activity and gonadal development.

This study aimed to investigate whether fluid shifts alter ciprofloxacin pharmacokinetics in critically ill patients over time. Patients >= 18 years, with normal renal function, requiring intensive care treatment and parenteral antibiotics were enrolled. Group A (22 patients) included patients with documented intra-abdominal infections. Group B (18 patients) included patients with severe sepsis from other causes. All patients received intravenous ciprofloxacin 400 mg every 8 h infused over 60 min. Eight timed blood specimens were taken on days 0, 2 and 7. Ciprofloxacin plasma concentrations were determined using high performance liquid chromatography. There were no significant differences between the pharmacokinetics of the two groups or over time. Ciprofloxacin pharmacokinetics in critically ill patients do not change over time, and intra-abdominal sepsis does not alter ciprofloxacin pharmacokinetic parameters to a greater degree than sepsis from other causes in critically ill patients. (c) 2005 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.