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Potentially mineralizable nitrogen (PMN) is a widely used indicator of a soil’s organic nitrogen (N) availability, and is often measured by incubation. While it is known that the handling of soil p...

Temperature extremes alter development, growth, hatching, and survival of eggs of ground-nesting birds, particularly during pre-incubation (egg laying) when eggs are left unattended and exposed to the environment for days or weeks before parental incubation begins. The northern bobwhite quail is a ground-nesting bird whose eggs experience high temperatures (≥45° C) during pre-incubation. It is known that chronic high temperatures during pre-incubation alter development and reduce hatching and survival of bobwhite eggs, but it is not known if acute doses of high temperatures during pre-incubation have the same effect. In this study, the 12-d pre-incubation period was divided into thirds. Fresh bobwhite eggs were exposed to either a commercial holding temperature for all 12 d (serving as a control), or a high oscillating temperature regimen for 4 d (one third of pre-incubation) either in the early, middle, or late third of pre-incubation, with a low oscillating temperature regimen during the remaining 8 d. The timing of acute exposure to high oscillating temperatures significantly affected bobwhite development. Eggs exposed in the first 2/3 of pre-incubation developed twice as much as eggs exposed late in pre-incubation, even though all eggs received the same amount of heating degree-hours. Thus, a critical window of thermal susceptibility exists for developing northern bobwhites. Acute exposure to high oscillating temperatures resulted in reduced hatchling mass, hatching success, survival, and compromised hatching synchrony. Thus, acute hyperthermic nest temperatures during pre-incubation could result in the observed reductions in the percentage of juveniles in natural populations during hot and droughty years.

Magnesium based implants could revolutionize applications where orthopedic implants such as nails, screws or bone plates are used because they are load bearing and degrade over time. This prevents a second surgery to remove conventional implants. To improve the biocompatibility we studied here if and for how long a pre-incubation of the material under cell culture conditions is favorable for cell attachment and proliferation. For two materials, Mg and Mg10Gd1Nd, we could show that 6 h pre-incubation are already enough to form a natural protective layer suitable for cell culture.

The effects of a specific rice starch (SRS), containing highly resistant starch (RSIII), on gel properties of grass carp (Ctenopharyngodon idella) and the influence of five levels of SRS (0%, 2%, 4%, 6%, and 8%w/w) on gel physicochemical properties at three different pre-incubation temperatures (4 °C, 25 °C, and 40 °C) were investigated. Gels with increasing amounts of SRS addition showed lower expressible water contents and cooking loss values than did control gels. SDS gel electrophoresis revealed no changes in protein patterns, regardless of different SRS-added levels at the same pre-incubation temperature, but an evident decrease in the MHC when the pre-incubation temperature increased. The texture properties, colour attributes, SEM were optimal in the treatments containing 4%w/w SRS at the pre-incubation temperature 25 °C. Thus, the optimum SRS addition level and pre-incubation temperature are proposed to be 4%w/w and 25 °C, respectively.

International audience; The zootechnical performances of broilers at the end of the rearing period depend in part on the quality of day-old chicks at placement. The quality of day-old chicks is highly affected by the incubation conditions, by hatch time (which determines the time spent in the hatcher under high temperature and humidity), and by the handling of chicks after hatch. This article first presents an overview of the most relevant pre-incubation factors that affect chick quality: egg size, egg weight, quality of eggs, sex of embryos, age of breeders, and conditions and duration of egg storage. It then reviews the most important incubation factors that affect hatch time, hatchability and hatch window (temperature, humidity, turning, ventilation and concentration of gases). Finally, the effect of early post-hatch handling (including processing and especially transportation of chicks) as a possible source of stress influencing the quality of chicks at placement is discussed

The Ames microplate format (MPF™) test, which uses liquid media and in 384-well microplates with a readout based on a colour-change, has been used for over 10 years at several major pharmaceutical companies for screening the genotoxic potential of early drug candidates when compound supply is minimal. Meanwhile, Xenometrix has adapted this screen from the two-strain Ames II test for use with five tester strains, in compliance with OECD Guideline 471. A set of 15 equivocal to weakly positive chemicals selected from the National Toxicology Program (NTP) database was tested simultaneously in the Ames microplate format (MPF) and the standard Ames pre-incubation method on agar plates. Such a direct comparison of the two test methods with the same overnight culture(s), chemicals and S9-mix preparation should exclude external variability factors. Thirteen of the 15 chemicals showed concordant results in both tests despite the choice of chemicals that showed varying inter- and even intra-laboratory results in the NTP studies. These results indicate that the Ames MPF™ assay is a reliable predictive tool that can be used like the regular Ames test to evaluate compounds for mutagenicity.

Biochemical methane potential tests were conducted to evaluate the effect of using a blank versus a pre-incubated inoculum in digestion of primary sludge at different waste to inoculum ratios (S/X). In addition, this study explored the influence of using two different anaerobic inoculum sources on the digestion of food waste: digested sludge from a municipal wastewater treatment plant and from a digester treating the organic fraction of municipal solid wastes. The results revealed that although there was no significant difference in methane yield (on average 114 mL CH4/g TCODsub) or biodegradability (on average 28.3%) of primary sludge using pre-incubated or non-incubated inocula, the maximum methane production rates using non-incubated inoculum were higher than those using pre-incubated inoculum at all S/X ratios. Moreover, interestingly the inoculum from an anaerobic digester treating municipal wastewater sludge was superior over the inoculum from anaerobic digester treating food waste in digesting food waste.

In this study, as a part of our efforts to improve the robustness and economical feasibility of cell-free protein synthesis, we developed a simple method of preparing the cell extracts used for catalyzing cell-free protein synthesis reactions. We found that the high-speed centrifugation, pre-incubation, and dialysis steps of the conventional procedures could be omitted without losing the translational activity of the resulting cell extract. Instead, a simple centrifugation step at low speed (12,000 RCF for 10 min) followed by a brief period of incubation was sufficient for the preparation of an active extract to support cell-free protein synthesis with higher productivity and consistency. Compared to the present standard procedures for the preparation of the S30 extract, the overall cost of the reagents and processing time were reduced by 80 and 60%, respectively.

Department of Polymer Science and Engineering, Kyoto Institute of Technology,Matsugasaki-Hashigamichou 1, Sakyo-ku, Kyoto 606-8585, Japan(Received September 2, 2005; Accepted October 25, 2005; Published March 15, 2006)KEY WORDS Insulin / Amyloid / High Pressure / Protein / Denaturation / Aggregation /[DOI 10.1295/polymj.38.302]

Nests of radiotransmittered wild turkeys (Meleagris gallopavo) that are destroyed or abandoned prior to incubation are particularly difficult to locate. As a result researchers often report only incubated nests or estimate numbers of nests attempted by localization of movement or other behavioral changes without quantification. We used radiotelemetry to obtain movement data on female wild turkeys during the nesting season (1 Apr-30 Jun) in South Dakota. We collected prelaying (1 April until 14 days before the female initiated incubation) and laying (

The aim of the studywas to define the egg parameters, which could be measured on an intact egg prior to incubation, to accuratelypredict chick weight after hatching. The eggs from laying hens of the White Leghorn, Rhode Island White and Rhode Island Red parent stocks were investigated. The results showed that egg volume (coefficient of variation CV = 6� 9%) and weight (CV = 6� 2%) were the most variable egg parameters as compared with less variable egg surface area (CV = 4� 5%) and density (CV = 3� 1%). There was no significant inter-strain difference in egg weight. Other egg parameters such as volume, shell surface area, density, and egg–chick weight ratios differed significantly. Chick weights differed significantly onlybetween the White Leghorn and Rhode Island White lines. Egg densitywas chosen as an indirect indicator of shell thickness and/or shell density, but the correlation between chick weight and egg density was too small (correlation coefficient R =0 � 02) to state that shell parameters influence much chick weight. Egg weight alone had the biggest correlation with chick weight (R =0 � 56) in comparison with egg volume (R =0 � 50) and surface area (R =0 � 50) for the combined data across three strains. The accuracyof the results of chick weights predicted bythe proposed mathematical equations and expressed in terms of coefficient of determination R 2 varied from 0� 250 to 0� 615, depending on the strain data and the type of the predictive formula. The best prediction was obtained for the quadratic type of the equation when three basic egg parameters (weight, volume and surface area) were considered. # 2002 Silsoe Research Institute. Published byElsevier

Soil microbial C and N (Cmic, Nmic) estimation by the chloroform fumigation-extraction method is erroneous in densely rooted soils due to CHCl3-labile C and N compounds. The effect of a pre-extraction with 50 mM K2SO4 and a pre-incubation (conditioning at 25 °C for 7 days) on the flush in extractable, CHCl3-labile C (C-flush) and N (N-flush) was tested with reference to rooting density (0.3—75 mg root dry matter g—1) in one arable and 3 grassland soils. In the arable soil and in the second horizon (10—20 cm) of a grassland soil, C-flush values were not affected by the pre-extraction. However, the pre-extraction considerably reduced C-flush values in the top soils of the grassland (above 10 cm). Only about 42 % was found in the pre-extracted roots and the rest was lost during the pre-extraction. The estimated concentrations of Nmic decreased due to pre-extraction of soil samples with low root biomass. Clearly, the concentrations of Nmic were underestimated by introducing the pre-extraction. Soil pre-incubation reduced C-flush values only slightly, whereas N-flush values were not affected. It can be concluded that (1) CHCl3-labile root C and N is partly extracted with K2SO4 after pre-incubation and (2) CHCl3-labile C and N removed with the roots during pre-extraction is partly derived from microbial biomass. Soils with low rooting density (arable soils, grassland soils below approximately 10 cm depth) should therefore be fumigated and extracted without pre-extraction. In densely rooted soils, fumigation extraction with and without pre-extraction probably gives estimates for the minimum and maximum of Cmic and Nmic. Einschrankungen bei der Quantifizierung des mikrobiellen Kohlenstoffs und Stickstoffs durch Fumigation-Extraktion in durchwurzelten Boden Die Abschatzung der Gehalte an bodenmikrobiellen C und N (Cmic, Nmic) mittels der Chloroform-Fumigations-Extraktions-Me-thode wird in stark durchwurzelten Boden durch CHCl3-labile C- und N-Verbindungen verfalscht. Der Effekt einer Vorextraktion und einer Vorinkubation (7 Tage bei 25 °C) auf die zusatzlich extrahierbare, CHCl3-labile C- und N-Menge (C-flush bzw. N-flush) wurde in Abhangigkeit von der Durchwurzelung (0.3—75 mg Wurzel-TM g—1) an einem Acker- und drei Grunlandboden gepruft. Die Ergebnisse zeigen, dass die Vorextraktion keinen Effekt auf den C-flush des Ackerbodens und des zweiten Horizonts (10—20 cm Tiefe) des Grunlandbodens hatte. Dahingegen nahm der C-flush jeweils in der oberen Schicht (bis 10 cm) der Grunlandboden deutlich ab. Lediglich ca. 42 % davon wurden in den vorextrahierten Wurzeln gefunden, und der Rest ging wahrend der Vorextraktion verloren. Die Vorextraktion verringerte den N-flush in Bodenproben mit geringer Wurzelmasse und fuhrte offensichtlich zu einer Unterschatzung des mikrobiellen N. Eine Vorinkubation der Bodenproben verringerte den C-flush dagegen nur wenig, der N-flush war unbeeinflusst. Es kann geschlussfolgert werden, dass (1) CHCl3-labiler Wurzel-C und -N nach der Vorinkubation teilweise mit K2SO4 extrahiert wird und (2) wahrend der Vorextraktion mit den Wurzeln entfernter, CHCl3-labiler C und N teilweise aus der mikrobiellen Biomasse stammt. Bodenproben mit geringer Durchwurzelungsdichte (Ackerboden, Grunlandboden unter ca. 10 cm Tiefe) sollten daher ohne Vorextraktion begast und extrahiert werden. In stark durchwurzelten Boden ergibt die Fumigations-Extraktions-Methode mit und ohne Vorextraktion wahrscheinlich Schatzwerte des Minimums bzw. Maximums von Cmic und Nmic.

1. Eggs were stored for two different times at varying temperatures. The effects on hatchability, chick weight at hatch and hatching time were examined in two broiler breeder lines from 33 to 58 weeks of age. 2. Short storage (1 to 3 d). Storage at 20 degrees C compared with 16.5 degrees C reduced hatchability of all eggs set. No effect was observed on hatchability of fertile eggs, hatching time or chick weight. 3. Long storage (9 to 11 d). Storage at 16.5 degrees C compared with 10 degrees C decreased both hatchability of fertile eggs and chick weight at hatch. Incidence of early embryonic death increased and incubation time decreased at 16.5 degrees C compared with 10 degrees C. 4. Chicks from morning eggs were heavier than those from afternoon eggs irrespective of storage conditions. 5. Hatchability (all eggs set and fertile eggs) and chick weight varied with hen age irrespective of storage conditions. During long storage, hatching time varied with hen age independently of breeder line, storage temperature or egg laying time. 6. Hatchability (all eggs set and fertile eggs) was higher in line A than in line B. Line B eggs hatched later and produced heavier chicks than line A eggs irrespective of storage time.

Two strains of Aeromonas hydrophila (the type strain ATCC 7966 and a food-derived strain JAH4) were pre-incubated at 5°C in Brain Heart Infusion (BHI) broth with pH adjusted to 6.0 or 7.0, and then incubated at the same temperature in BHI broth with pH adjusted to 6.0, 6.5, 7.0 and 7.5. Growth kinetics during incubation were determined by two methods: viable count (VC) and measurement of optical density (O.D.). Pre-incubation at different pH values did not significantly affect the maximum specific growth rates of the strains during incubation, but the lag phases were shorter after pre-incubation at pH 6.0 than at pH 7.0. The VC method was more sensitive than O.D. measurements for assessing lag phase.

The time between a hatching egg being produced and set in an incubator can be divided into a laying house period and a storage period. The period in the laying house affects hatching results by the...

From 1986 to 1990 we studied the vocalizations of 10 mated pairs of Cooper's Hawks (Accipiter cooperii) during the pre-incubation stage. We heard four different vocalizations during nest-building, copulatory, and other pre-laying activities. There was a marked asymmetry in vocalizations between the sexes during the pre-incubation period. Compared to males, female Cooper's Hawks (1) had a larger repertoire of calls, (2) called more frequently, and (3) called during a wider array of activities. We suggest that the various calls signal presence, identity, location, dominance, and non-aggressive motivation. We attribute some of the intersexual differences in pre-incubation vocalizations to the pronounced degree of reversed sexual size dimorphism in this species.

The effect of prior incubation temperature (5, 15, 25 and 35°C) on the lag times of two strains of Aeromonas hydrophila at the same four incubation temperatures was assessed. When grown at 5°C the type strain (ATCC 7966) showed a 28-fold difference in lag time depending on whether the inoculum had been incubated at 5 or 35°C. However, the corresponding factor for a food-derived strain was only 4. A similar effect was observed, to a lesser extent, under most of the conditions used. Prior incubation temperature had no effect on generation time.

Effects of pre-incubation upside-down positioning of eggs (from collection time at the farm until delivery to the hatchery, which can be up to 5 days) and breeder flock age on hatchability and chick quality were investigated. In this study, 5400 eggs from broiler breeder flocks were assigned to two groups (upside-down and normal position eggs as Control group). The birds were divided in three age groups (46, 73 and 107 weeks of age). Each age group had six replicates with 150 eggs per replicate. The results indicated that keeping eggs in an upside-down position reduced (P < 0.05) hatchability by 4.3% compared with the Control (normal position) group. Also, reversed egg positioning significantly increased relative intestine weight (P < 0.05) and percentage of embryo mortality between 18–19 days of incubation (P < 0.01). Flock age affected (P < 0.01) hatchability, egg shape index, chick cull percentage, infertile eggs, total embryo mortality, percentage egg weight loss and chick yield. The lowest hatchability and the highest percentage egg weight loss were observed in flocks with 107 weeks of age.

Rumen fluid was extracted from sheep after they had been deprived of food for 48 hours. This rumen fluid was either directly applied in an artificial rumen or after pre-incubation (up to 16 hours). The 35S-incorporation rate into the microbial protein was measured after the admixture of untreated straw meal, straw meal treated with NH3-water of with NaOH. Generally, the 35S-incorporation rates were highest for the blank experiments. The reason for this is that the straw meal admixtures withdraw from the microorganisms low-molecular, energetically utilisable substrates by absorption and adsorption. Pre-incubation could not much reduce the relatively higher 35S-incorporation rate of the blank experiments. The two treated straw variants were significantly superior to the untreated straw meal concerning the 35S-incorporation rate.

The detection limits of drugs in quantitative RRA are primarily determined by their affinities towards the receptor. Yet, the concentration of radiolabeled ligand, necessary for quantification of receptor-bound drug, increases the theoretical detection limit. Therefore the influences of low temperatures and pre-incubation on the detection limit was studied. Analysis of experimental data suggests that when a well-defined incubation procedure is used, pre-incubation and low temperatures will increase sensitivity without loss of accuracy and precision. 6 references, 2 figures.

The soil-inhabiting nematode Labronema digitatum, when exposed to an electric field at 0.06 mA of current, migrated to the cathode in tap water and also in solutions of NiCl2, MnCl2 and ZnCl2 at the salt concentration of tap water (34 × 10-2 to 42 × 10-2 g/l) . The nematodes showed cathodic electrotaxis at all concentrations between 2 × 10-3 and 50 × 10-1 g/l of those salt solutions only when they were pre-incubated in the test concentration for 1 h. No pre-incubation was required for electrotactic response in tap water because the nematodes are normally adapted to the ionic concentration of tap water in their natural soil environment. It is suggested that necessary adjustment with respect to the balance in osmotic pressure between the body fluid of nematodes and the ambient medium is a necessary prerequisite during preincubation in the test concentrations.

Thermal death of Cryptococcus neoformans in the presence of amphotericin B was strongly dependent upon the temperature of pre-incubation. The entropy coefficient, that is, the increase in entropy of activation of thermal death per square unit concentration of the drug in the medium, was 35 times higher after pre-incubation at 25 degrees C than at 39 degrees C. This means that C. neoformans cells grown at lower temperatures were much more sensitive to the temperature-dependent fungicidal effect of amphotericin B.

Beim Ubergang vom Ruhezustand in den der Stoffwechselaktivitat zeigt eine anaerob vorkultivierte Hefe im Gegensatz zu einer aeroben eine NADH-Uberkompensation. Diese wurde von Holzer (1960) mit der zeitlichen Differenz zwischen einer NADH-produzierenden und einer NADH-verbrauchenden Reaktion gedeutet. Eingehende Untersuchungen zeigten, das diese NADH-Zunahme nur bei der aeroben Kultur effektiv mesbar ist, wahrend bei der anaeroben Hefe eine starke Uberlagerung zusatzlich auftritt. Es konnte gezeigt werden, das dieser peak der anaeroben Hefe nicht aus der GAP-Dehydrierung, sondern aus der Dehydrierung endogenen Alkohols stammt. Der peak ist direkt vom Alkohol-Spiegel abhangig und nicht durch Azid, Cyanid oder Monojodessigsaure beeinflusbar.

Effect of calcium and hydrogen ion on the fibrinolytic activity of isolated renal glomeruli from rat. The fibrinolytic activity of glomeruli isolated from rat kidney has been measured with 125 I-fibrin-coated tubes. This technique allows the study of the two successive steps of the reaction: the release of the activator of plasminogen from the cells in the presence of isolated glomeruli, and the enzymatic process itself in the presence of the supernatant obtained after a 30-min incubation period with isolated glomeruli and centrifugation. Calcium in the range of 0.01 to 1.0mM increased the rate of fibrinolysis and shortened the lag-time preceding this effect. The fibrinolytic activity was also measured in the presence of isolated glomeruli as a function of the plasminogen concentration. Calcium at 1mM clearly increased the maximum velocity but did not change the concentration of plasminogen corresponding to 50% of the maximum. Supernatants were obtained after preincubation of isolated glomeruli with increasing doses of calcium. Addition of these supernatants to the 125 I-fibrin-coated tubes produced a progressive increase in the rate of fibrinolysis, depending on the dose of calcium. When calcium was added to the supernatants only, after having discarded the glomeruli, there was no change or, above 0.5mM calcium, a slight inhibition of the enzymatic reaction itself. The fibrinolytic activity measured in the presence of isolated glomeruli was maximum at a pH of 8. There was a clear-cut interaction in this condition between pH and calcium concentration. This interaction was not observed when the isolated glomeruli had been discarded. These results clearly demonstrate the major role of calcium in the release from glomeruli of an activator of plasminogen. Effet du calcium et de l'ion hydrogene sur l'activite fibrinolytique de glomerulus isoles de reins de rat. L'activite fibrinolytique de glomerules isoles de rein de rat a ete mesuree en utilisant des tubes sur lesquels de la 125 I fibrine a ete fixee. Cette technique permet d'apprecier les 2 etapes de la reaction: sortie de l'activateur cellulaire du plasminogene lorsque les glomerules isoles sont presents dans le milieu d'incubation et reaction enzymatique ellememe lorsque le surnageant obtenu apres 30min d'incubation et elimination des glomerules isoles par centrifugation est etudie. Le calcium entre 0.01 et 1.0mM augmente la quantite de fibrine lysee et raccourcit le temps de latence necessaire a cet effet. L'activite fibrinolytique a aussi ete mesuree en presence de glomerules isoles en fonction de la concentration de plasminogene. Le calcium a la concentration de 1mM augmente clairement la vitesse maximale mais ne change pas la concentration de plasminogene correspondant a 50% de l'effet maximum. Des surnageants ont ete obtenus apres pre incubation de glomerules isoles dans des milieux contenant des concentrations croissantes de calcium. L'adjonction de ceux-ci aux tubes sur lesquels de la 125 I fibrine a ete fixee entraine une augmentation croissante de la quantite de fibrine lysee dependante de la dose de calcium. Quand du calcium a ete ajoute a un surnageant obtenu apres avoir elimine les glomerules isoles il n'y a pas eu de modification de la fibrinolyse ou une legere inhibition de la reaction enzymatique pour des concentrations de calcium superieures a 0.5mM. L'activite fibrinolytique mesuree en presence de glomerules isoles a ete maximum a pH 8. Il y a eu une interaction claire entre le pH et la concentration de calcium qui n'a pas ete observee lorsque les glomerules ont ete elimines. Ces resultats demontrent clairement le role majeur du calcium dans la sortie des glomerules d'un activateur du plasminogene.

Une pre-incubation de 8 h a 4°C augmente la sensibilite du test d'inhibition de croissance en gelose utilise pour la detection d'antibiotiques insolubles dans l'eau: application a l'etude d'un extrait cellulaire methanolique d'une algue d'eau douce Pleurastrum terrestre

Since the publication of the original Salmonella mutagenicity test protocol in 1975, a number of investigators have proposed that the addition of a pre-incubation step to the normal protocol increases the sensitivity of the assay. Data presented here for 4-dimethylaminoazobenzene and the more potent carcinogenic analogue 6-dimethylaminophenylazobenzothiazole show that simply varying the amount of S9 present in the plate assay can increase the sensitivity of the test as much as the addition of the pre-incubation step does.

Veranderungen des Huhnereiweisses durch Lagerung konnen in der Immunprazipitation (Ouchterlony-Test) erfasst werden.