scholarly journals Hatch traits of artificially incubated ostrich eggs as affected by setting position, angle of rotation and season

2020 ◽  
Vol 50 (4) ◽  
pp. 607-612
Author(s):  
Z. Brand ◽  
S.W.P. Cloete ◽  
C.R. Brown
Keyword(s):  
Factorial Design ◽  
Position Angle ◽  
Moisture Loss ◽  
Horizontal Position ◽  
Breeding Seasons ◽  
Considerable Loss ◽  
Artificial Incubation ◽  
Angle Of Rotation

High levels of hatching failure in artificially incubated ostrich eggs cause considerable loss of income for the industry. In the 2015 - 2016 breeding seasons, between 846 and 1 549 egg records were used to determine the effect of various setting positions during artificial incubation. Fresh eggs were placed in trolleys in the setter that were turned automatically hourly through 60 degrees or 90 degrees. The additional treatments as factorial design included eggs set horizontally for five weeks in the setter; in horizontal position for three weeks and vertically for two weeks; and vertically for five weeks. These treatments were repeated over two production years to represent the seasons, namely winter (June to August), spring (September to November), and summer (December). Late embryonic mortalities improved significantly in eggs that were set to turn through 90 degrees (0.16 ± 0.02) compared with those set to turn through 60 degrees (0.28 ± 0.02), regardless of season and setting position. The preferred way of setting ostrich eggs would therefore be vertically in a trolley that turns hourly through 90 degrees with the air cell upwards to utilize incubator space optimally.Keywords: chick weight, embryonic mortalities, ostrich, pipping time, moisture loss

scholarly journals Hatch traits of artificially incubated ostrich eggs as affected by setting position, angle of rotation and season

2021 ◽  
Vol 50 (5) ◽  
Author(s):  
Z. Brand ◽  
S.W.P. Cloete ◽  
C.R. Brown
Keyword(s):  
Factorial Design ◽  
Position Angle ◽  
Moisture Loss ◽  
Vertical Position ◽  
Horizontal Position ◽  
Total Period ◽  
Breeding Seasons ◽  
Considerable Loss ◽  
Artificial Incubation ◽  
Angle Of Rotation

High levels of hatching failure in artificially incubated ostrich eggs cause considerable loss in income for the industry. During the 2015 - 2016 breeding seasons, between 846 and 1 549 egg records were used to determine the effect of various setting positions during artificial incubation. Fresh eggs were placed in trolleys to be turned automatically through a 60-degree or a 90-degree angle hourly in the setter. Additional treatments in a factorial design consisted of eggs set in the horizontal position for the total period of five weeks in the setter; eggs set horizontally for three weeks and vertically for two weeks; and eggs set vertically for five weeks in the setter. These treatments were repeated over two production years to represent various seasons, namely winter (June to August), spring (September to November) and summer (December). Late embryonic mortalities were improved significantly in eggs set in trolleys to turn through an angle of 90 degrees (0.16 ± 0.02) compared with eggs set in trolleys to turn through 60 degrees (0.28 ± 0.02), regardless of season and setting position. The preferred way of setting ostrich eggs would thus be in the vertical position in a trolley that turns hourly through an angle of 90 degrees with the air cell upwards to utilize incubator space optimally. Keywords: chick weight, embryonic mortalities, moisture loss, ostrich, pipping time

scholarly journals CONSTRUCTION OF ROTOR ANGLE IDENTIFIER IN VECTOR CONTROL SYSTEMS OF DOUBLE FEED MACHINES

2021 ◽  
Vol 2 (39) ◽  
pp. 74-81
Author(s):  
О. Klyuyev ◽  
A. Sadovoi ◽  
Y. Sokhina
Keyword(s):  
Vector Control ◽  
Control Systems ◽  
Angular Position ◽  
Position Angle ◽  
Identification Accuracy ◽  
Electric Drives ◽  
Operating Modes ◽  
Complex Structural ◽  
Conditions Of Stability ◽  
Angle Of Rotation

In asynchronous electric drives with vector control on the rotor, it is necessary to calculate the value of the sine and cosine of the angle of rotation of the rotor relative to the stator to form control actions. When using angle sensors, complex structural tasks can arise — placement and reliable mounting of the sensor on the shaft and, accordingly, the task of the overall layout of the unit. For high-power machines, the tasks of developing and creating the design of the sensor itself arise. If serial rotor angular position sensors can be used, the task of placing and mounting the sensor is no less difficult. In these cases it is necessary to deduce the second end of a shaft from the case of the engine with contact rings that complicates its design. Therefore, the urgent need to create more reliable electric drives with vector control systems on the rotor is the synthesis of identifiers of the angle of rotation of the rotor. Identifiers are known whose calculation algorithms are based on determining the projections of the flow coupling vectors. In the work with the use of coordinate transducers of projections of stator or rotor current vectors and equations of electromagnetic circuits of an asynchronous machine, the synthesis and subsequent analysis of the properties of the rotor position angle identifier in vector control systems of dual power machines is performed. New equations of the identifier of flux couplings are received, its stability is investigated and on conditions of stability types of electric drives in which it is possible to apply the offered identifier are defined. The stability of the vector control system and sufficient identification accuracy when using the proposed equations and functions are confirmed by the method of mathematical modeling of the recommended electric drive systems in different operating modes.

Factors Related to the Artificial Incubation of Wild Bird Eggs

2009 ◽  
Vol 2 (3) ◽  
pp. 121-131 ◽  
Author(s):  
Jon D. Klimstra ◽  
Katherine R. Stebbins ◽  
Gary H. Heinz ◽  
David J. Hoffman ◽  
Shannon R. Kondrad
Keyword(s):  
Wild Species ◽  
Wild Bird ◽  
Hatching Success ◽  
Wild Birds ◽  
Moisture Loss ◽  
Similar Species ◽  
Critical Elements ◽  
Bird Eggs ◽  
Artificial Incubation ◽  
Successes And Failures

Attempts to artificially incubate the eggs of wild birds have failed in many respects in duplicating the success of natural incubation. As part of a larger study we had the opportunity to artificially incubate the eggs of 22 species of birds (three domestic and 19 wild species). We report the successes and failures associated with artificial incubation of these eggs. Moisture loss varied widely, not only for Orders of birds but for similar species within an Order. Overall hatching success and success through to 90% of incubation varied for different Orders and for similar species. Humidity and temperature are critical elements in the artificial incubation of wild bird eggs and must be closely monitored throughout incubation to ensure the best possible chance of hatching. Even when these elements are addressed, artificial incubation still cannot duplicate the success of incubation by the parent.

Development and Optimization of Mouth Dissolving Film of Granisetron using 32 Factorial Design and Response Surface Methodology

1970 ◽  
Vol 9 (1) ◽  
pp. 3118-3129
Author(s):  
Vipul K. Sapavadiya ◽  
Miral V. Sapavadiya ◽  
Pragna K. Shelat ◽  
Anita N. Lalwani
Keyword(s):  
Experimental Design ◽  
Drug Release ◽  
Factorial Design ◽  
Desirability Function ◽  
Research Work ◽  
Stability Study ◽  
Moisture Loss ◽  
Peg 400 ◽  
Weight Variation ◽  
32 Factorial Design

Granisetron is a highly selective serotonin (5-HT3) receptor blocker which prevents the vomiting reflex induced by serotonin during cancer chemotherapy. The objective of present research work was development and optimization of mouth dissolving film of granisetron hydrochloride. Solvent casting method was used for preparation of mouth dissolving film. Various film forming polymers like PVP K-30, PVA, maltodextrin, HPMC E5 LV and lycoat RS 720 along with and plasticizer like Propylene glycol, Poly ethylene glycol 400 and glycerin were used for selection of suitable polymer plasticizer combination. Film prepared using lycoat RS 720 and PEG-400 was found satisfactory and further factorial design and desirability function was used for optimization. Regression equation and counter plots were executed to dependent variables i.e., tensile strength, % elongation, elastic modulus and % drug release in 1 minutes to independent variables. Results of experimental design revealed that the independent factors lycoat RS 720 and PEG-400 significantly influenced the mechanical properties and % drug release from the film which was ultimately reflected in this formulation of optimized batch. All experimental design formulations were evaluated for weight variation, thickness, drug content, % moisture loss, pH, folding endurance and stability study at 40˚ ± 2˚ C/75 ± 5% RH. From the result of optimized batch it can be concluded that an optimized formulation was stable with suitable packaging and the high % drug release of film in simulated saliva indicate that it can be used for drug delivery system of granisetron hydrochloride having first pass metabolism

scholarly journals Reintroduction of hand-reared alala Corvus hawaiiensis in Hawaii

Oryx ◽  
1995 ◽  
Vol 29 (4) ◽  
pp. 261-266 ◽  
Author(s):  
C. Kuehler ◽  
P. Harrity ◽  
A. Lieberman ◽  
M. Kuhn
Keyword(s):  
Endangered Species ◽  
The State ◽  
Private Land ◽  
National Academy Of Sciences ◽  
Land Owners ◽  
The Us ◽  
In The Wild ◽  
Breeding Seasons ◽  
Academy Of Sciences ◽  
Artificial Incubation

The wild alala Corvus hawaiiensis population has been declining for many years and only three pairs of birds are currently reproductively active on the island of Hawaii. At the recommendation of a committee formed by the National Academy of Sciences, a restoration programme was initiated in 1993 by The Peregrine Fund in collaboration with private land-owners, the US Fish and Wildlife Service, National Biological Service and the State of Hawaii. The restoration programme includes removing eggs from wild nesting birds for artificial incubation, handrearing and reintroduction. In two breeding seasons (1993, 1994), 17 eggs were removed from alala nests in the wild. Three eggs were infertile, 13 chicks hatched and 12 alala were successfully reared (hatchability: 93 per cent; survivability: 92 per cent). Four of these chicks were sent to the State of Hawaii's Olinda Endangered Species Propagation Facility, while four chicks from this facility were sent to the reintroduction programme. Twelve alala have been released by The Peregrine Fund: five in 1993 and seven in 1994. Three of the five birds released in 1993 and all seven of the birds released in 1994 are currently surviving in the wild.

scholarly journals Factors related to shell deaths during artificial incubation of ostrich eggs

2007 ◽  
Vol 78 (4) ◽  
Author(s):  
Z. Brand ◽  
S.W.P. Cloete ◽  
C.R. Brown ◽  
I.A. Malecki
Keyword(s):  
South African ◽  
Black Males ◽  
Hatching Success ◽  
Embryonic Mortality ◽  
High Rate ◽  
Detailed Knowledge ◽  
Black Females ◽  
Negative Effect ◽  
Breeding Seasons ◽  
Artificial Incubation

he ostrich industry experiences a high rate of embryonic mortalities during artificial incubation of eggs. Embryonic deaths were studied from data recorded on 37 740 fertile eggs incubated artificially during the 1998-2005 breeding seasons. Roughly 10 000 eggs that sustained embryonic mortalities were classified according to the stage and nature of death, i.e. before 21 days of incubation, after 21 days of incubation, deaths after pipping and rotten eggs. Although infection may have played a role in ~1300 rotten eggs, no detailed knowledge of the pathogens involved was available. The remainder of deaths could not be related to pathogens and the deaths were thus generally referred to as non-infectious. The overall level of embryonic mortality in all the eggs studied was 28.5 %. Overall embryonic mortality was affected by incubator, with higher levels (57.0 %) found in eggs incubated in an African Incubator(R) and also in eggs that were transferred between incubators during incubation (38.1 %). Overall embryonic mortality also increased in eggs produced by older females. Eggs produced in the autumn had the highest level of embryonic mortality at 53.6 %, whereas eggs produced in the winter had a marginally higher level of embryonic mortalities of 29.2 % compared with eggs produced during summer (27.4 %). Eggs produced by South African (SA) Black males crossed to Zimbabwean Blue females had high levels of embryonic losses of 45.7 %. The embryonic mortality of eggs produced by SA Blacks or Zimbabwean Blue breeding birds subjected to pure breeding was similar at ~33-34 %, but embryonic mortality was improved in eggs produced by Zimbabwean Blue males crossed to SA Black females (27 %). Embryonic mortality was increased in eggs that were set directly (32.0 %) or subjected to longer than 6 days of storage (43.5 %). Embryonic mortality was affected by year. The results that were obtained will assist in determining non-infectious factors that have a negative effect on hatching success. Steps can thus be taken to eliminate such factors that may compromise hatching success.

The Shikani HME: A New Tracheostomy Heat and Moisture Exchanger

2020 ◽  
Vol 63 (9) ◽  
pp. 2921-2929
Author(s):  
Alan H. Shikani ◽  
Elamin M. Elamin ◽  
Andrew C. Miller
Keyword(s):  
Ex Vivo ◽  
Moisture Loss ◽  
Speaking Valve ◽  
Time Zero ◽  
In Series ◽  
Turbulent Airflow ◽  
The Difference ◽  
Loss Efficiency ◽  
Heat And Moisture ◽  
Lung Simulation

Purpose Tracheostomy patients face many adversities including loss of phonation and essential airway functions including air filtering, warming, and humidification. Heat and moisture exchangers (HMEs) facilitate humidification and filtering of inspired air. The Shikani HME (S-HME) is a novel turbulent airflow HME that may be used in-line with the Shikani Speaking Valve (SSV), allowing for uniquely preserved phonation during humidification. The aims of this study were to (a) compare the airflow resistance ( R airflow ) and humidification efficiency of the S-HME and the Mallinckrodt Tracheolife II tracheostomy HME (M-HME) when dry (time zero) and wet (after 24 hr) and (b) determine if in-line application of the S-HME with a tracheostomy speaking valve significantly increases R airflow over a tracheostomy speaking valve alone (whether SSV or Passy Muir Valve [PMV]). Method A prospective observational ex vivo study was conducted using a pneumotachometer lung simulation unit to measure airflow ( Q ) amplitude and R airflow , as indicated by a pressure drop ( P Drop ) across the device (S-HME, M-HME, SSV + S-HME, and PMV). Additionally, P Drop was studied for the S-HME and M-HME when dry at time zero (T 0 ) and after 24 hr of moisture testing (T 24 ) at Q of 0.5, 1, and 1.5 L/s. Results R airflow was significantly less for the S-HME than M-HME (T 0 and T 24 ). R airflow of the SSV + S-HME in series did not significant increase R airflow over the SSV or PMV alone. Moisture loss efficiency trended toward greater efficiency for the S-HME; however, the difference was not statistically significant. Conclusions The turbulent flow S-HME provides heat and moisture exchange with similar or greater efficacy than the widely used laminar airflow M-HME, but with significantly lower resistance. The S-HME also allows the innovative advantage of in-line use with the SSV, hence allowing concurrent humidification and phonation during application, without having to manipulate either device.

Effect of Thrombin on Phosphorylation of Platelet Membrane Proteins

1976 ◽  
Vol 35 (03) ◽  
pp. 635-642 ◽  
Author(s):  
M Steiner
Keyword(s):  
Protein Kinase ◽  
Kinase Activity ◽  
Qualitative Change ◽  
Protein Kinase Activity ◽  
Protein Substrates ◽  
Phosphoprotein Phosphatase ◽  
Progressive Loss ◽  
Platelet Membranes ◽  
Endogenous Protein ◽  
Considerable Loss

SummaryThe effect of thrombin on the phosphorylating activity of platelet membranes was compared to that of trypsin. Preincubation of non-32P phosphorylated platelet membranes with or without either of these two enzymes resulted in a considerable loss of membrane protein kinase activity which was most severe when trypsin was used. Protein kinase activity and endogenous protein acceptors decreased in parallel. 32P-phosphorylated membranes showed a slow but progressive loss of label which was accelerated by trypsin. Thrombin under these conditions prevented the loss of 32P-phosphate. These results are interpreted to indicate a thrombin-induced destruction of a phosphoprotein phosphatase. The protein kinase activity of phosphorylated platelet membranes using endogenous or exogenous protein substrates showed a significant reduction compared to non-phosphorylated membranes suggesting a deactivation of protein kinase by phosphorylation of platelet membranes. Neither thrombin nor trypsin caused a qualitative change in the membrane polypeptides accepting 32P-phosphate but resulted in quantitative alterations of their ability to become phosphorylated.

The Rain Calls of Frogs and the Reigning Paradigm of American Herpetology

2020 ◽  
pp. 1-35
Author(s):  
Gordon L. Miller
Keyword(s):  
Twentieth Century ◽  
Animal Communication ◽  
The United States ◽  
Emotional States ◽  
Breeding Sites ◽  
Gradual Disappearance ◽  
The Times ◽  
Traditional Natural ◽  
Breeding Seasons ◽  
The Comparative Study

American zoologists and herpetologists during the past fifty years have successfully deciphered the mating calls of frogs and toads with ever increasing precision and sophistication. However, the vocalizations most commonly termed “rain calls,” which typically occur beyond both normal breeding seasons and breeding sites, have remained a persistent puzzle. This article traces the gradual disappearance of rain calls, along with a corresponding decline in any mention of emotional states, from herpetological studies of anuran vocalizations in the United States from the middle of the twentieth century to the present and examines the historical roots of this disappearance. This evaporation of rain calls is indicative of a much larger change in the scientific climate of the times involving the transition from traditional natural history to the Neo-Darwinian, adaptationist paradigm of contemporary biology. Rain calls thus increasingly became anomalous, thereby eliminating a possibly fruitful line of inquiry in the comparative study of human-animal communication, in this case with evolution's earliest vocalizers. The contours and benefits of a more encompassing paradigm, envisioned by some leading early twentieth-century zoologists, are briefly discussed.

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