40 research outputs found
Meat quality, skin damage and reproductive performance of ostriches exposed to extensive human presence and interactions at an early age
The effect human presence and interactions performed after hatch to 3 months of age has on ostrich meat quality, skin damage
and reproductive performance at a later age was investigated in 416-day-old ostrich chicks. The chicks were allocated to one of
the three treatments, which varied with regard to exposure to human presence and care for 3 months post-hatch: HP1âextensive
human presence with physical contact (touch, stroking), gentle human voice and visual contact; HP2âextensive human presence
with gentle human voice and visual contact without physical contact; Sâstandard control treatment, where human presence and
visual contact were limited to routine management, feed and water supply only. Carcass attributes (carcass weight, dressing
percentage and drumstick weight), meat quality traits (pH, colour and tenderness) and skin traits (skin size, skin grading and
number of lesions) were evaluated on twenty-four 1-year-old South African Black (SAB) ostriches
Multi-Target Prediction: A Unifying View on Problems and Methods
Multi-target prediction (MTP) is concerned with the simultaneous prediction
of multiple target variables of diverse type. Due to its enormous application
potential, it has developed into an active and rapidly expanding research field
that combines several subfields of machine learning, including multivariate
regression, multi-label classification, multi-task learning, dyadic prediction,
zero-shot learning, network inference, and matrix completion. In this paper, we
present a unifying view on MTP problems and methods. First, we formally discuss
commonalities and differences between existing MTP problems. To this end, we
introduce a general framework that covers the above subfields as special cases.
As a second contribution, we provide a structured overview of MTP methods. This
is accomplished by identifying a number of key properties, which distinguish
such methods and determine their suitability for different types of problems.
Finally, we also discuss a few challenges for future research
Depositional architecture of sand-attached and sand-detached channel-lobe transition zones on an exhumed stepped slope mapped over a 2500 km2 area
The geomorphology and seismic stratigraphy of deep-water clastic systems from slope valleys through channel-levee systems to basin-floor fans have been observed and described in modern and ancient sub surface examples around the world. However, the distribution of sedimentary facies, grain size, and small-scale architectural elements remains poorly constrained. Extensive exposures (>2500 km2) of four stacked deep-water composite sequences have been mapped from heterolithic channel-levee systems on the slope to sand-rich basin-floor deposits. The data set from Units C-F of the Fort Brown Formation in the Permian Laingsburg depocenter of South Africa permits a unique opportunity to document and compare their depositional architecture at a high resolution for tens of kilometers downdip. Isopach thickness maps indicate that compensational stacking across multiple stratigraphic scales occurs on the basin floor, whereas preferred axial pathways were present on the slope, leading to subvertical stacking patterns. Units C and D are sand-attached systems; slope valley systems are mapped to pass transitionally downslope through leveeconfined channels to lobe complexes over distances of >30 km. The slope valley fills of Units E and F, however, are separated from their downdip sand-rich lobe complexes by a thin, sand-poor tract several kilometers in length and are termed sand detached. Locally, this sand-poor tract is characterized by a distinctive facies association of thin-bedded turbidites with numerous scours mantled with rip-up clasts, and a top surface that includes megaflutes and remobilized sediments. This assemblage is interpreted to indicate a widespread area of sand bypass. This unique data set provides an exploration- scale insight and understanding of how different segments of a prograding slope evolved over time in terms of gradient, physiography, and hence the degree to which sand was stored or bypassed to the basin floor, and the evolution from sand-attached to sand-detached systems. The development of sand-detached systems suggests that a steeper gradient formed, possibly related to developing underlying structure, that led to the development of a stepped slope profile. The study highlights that updip stratigraphic trapping at reservoir scale can occur with minor bathymetric changes
Return to sport soccer after anterior cruciate ligament reconstruction: ISAKOS consensus
Many factors can affect the return to pivoting sports, after an Anterior Cruciate Ligament Reconstruction. Prehabilitation, rehabilitation, surgical and psychological aspects play an essential role in the decision to return to sports. The purpose of this study is to reach an international consensus about the best conditions for returning to sports in soccer-one of the most demanding level I pivoting sports after anterior cruciate ligament (ACL) reconstruction
Recommended from our members
ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries.
This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors
ENIGMA and global neuroscience: A decade of large-scale studies of the brain in health and disease across more than 40 countries
This review summarizes the last decade of work by the ENIGMA (Enhancing NeuroImaging Genetics through Meta Analysis) Consortium, a global alliance of over 1400 scientists across 43 countries, studying the human brain in health and disease. Building on large-scale genetic studies that discovered the first robustly replicated genetic loci associated with brain metrics, ENIGMA has diversified into over 50 working groups (WGs), pooling worldwide data and expertise to answer fundamental questions in neuroscience, psychiatry, neurology, and genetics. Most ENIGMA WGs focus on specific psychiatric and neurological conditions, other WGs study normal variation due to sex and gender differences, or development and aging; still other WGs develop methodological pipelines and tools to facilitate harmonized analyses of "big data" (i.e., genetic and epigenetic data, multimodal MRI, and electroencephalography data). These international efforts have yielded the largest neuroimaging studies to date in schizophrenia, bipolar disorder, major depressive disorder, post-traumatic stress disorder, substance use disorders, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism spectrum disorders, epilepsy, and 22q11.2 deletion syndrome. More recent ENIGMA WGs have formed to study anxiety disorders, suicidal thoughts and behavior, sleep and insomnia, eating disorders, irritability, brain injury, antisocial personality and conduct disorder, and dissociative identity disorder. Here, we summarize the first decade of ENIGMA's activities and ongoing projects, and describe the successes and challenges encountered along the way. We highlight the advantages of collaborative large-scale coordinated data analyses for testing reproducibility and robustness of findings, offering the opportunity to identify brain systems involved in clinical syndromes across diverse samples and associated genetic, environmental, demographic, cognitive, and psychosocial factors
Stratigraphy and facies architecture of the uppermost fan system in the Tanqua sub-basin, Permian Ecca Group, South Africa
Thesis (MSc)--Stellenbosch University, 2005.ENGLISH ABSTRACT: Fan System 5 forms the uppermost submarine fan system of the Permian-age Tanqua Fan
Complex (Ecca Group) of the southwestern Karoo Basin. It is the most widespread system and
represents the final phase of fan deposition in the Tanqua sub-basin. Depositional characteristics
differ markedly from the rest of the fan systems, mainly because it lacks sedimentary features
indicative of a single point source basin floor fan. The entire system consists of six different
stages of fan growth and development in the lower slope settings.
A hypothetical model was composed for Fan System 5 to understand the spatial/temporal
distribution of reservoir and seal facies in slope turbidite settings. The facies vary from massive
amalgamated sandstone beds to thin-bedded, ripple cross-laminated sand and siltstone beds. A
thick shale unit identified as a regional marker layer overlies Fan System 5. lts base is defined by
the presence of a regionally developed 20 cm thick hemipelagic shale unit.
Six sand-rich units with channel-complexes are present in the Klein Hangklip, Groot Hangklip,
Kalkgat, Tongberg, Skoorsteenberg and Blauwkop localities. The facies characteristics in the
southernmost outcrops of Fan System 5 (Groot Hangklip, Tongberg and Kalkgat) reflect
deposition in a lower slope setting where local structural control seems to have played a major
role in the distribution and regional development of channel-fill and overbank depositional
elements.
The channel-fills are arranged in vertical to off-set stacking patterns and are comprised of
massive, amalgamated [me to very fine-grained sandstone units up to 30 m in thickness. They are
separated by thinner sandstone/siltstone units of varying thickness. The channelization displayed
by the more proximal outcrops are interpreted to represent an upper fan, deposited in a lower- to
mid-slope setting. In contrast to the channel-fill deposits at Skoorsteenberg, Klein Hangklip and
Groot Hangklip, ripple cross-laminated overbank deposits, associated with smaller channel-fill
units, predominate in the northeastern and eastern parts of the outcrop area. Massive- and thinbedded
frontal sheet sandstones constitute the down-dip extensions to the most northern outcrops
of Fan System 5. Highly erosive, stacked base-of-slope channel complexes, seemingly controlled by subtle early
structural features, were able to construct significant thicknesses of regionally well-developed
overbank deposits, marginal to the channel complexes. These facies changes occur over relatively
short distances, which hold significant implications for the prediction of and the heterogeneity of
reservoir facies in slope settings.
Gradients are much steeper in the lower slope to mid-slope area than on the proximal basin floor.
The occurrence of soft-sediment deformation in the overbank and upper parts of the channel-fill
deposits supports a slope origin. Weakly developed wave-ripple marks in the uppermost layers of
Fan System 5 further indicate that water depths approached wave base prior to deposition of the
upper markerbed shales.
Paleotransport for Fan System 5 was towards the north, northeast and east. The palaeocurrent
directions of the channel-fill complexes in Klein- and Groot Hangklip seem to roughly
correspond to the structural trend of synclinal depressions in this area. However, the effect and
influences of basin floor topography and structural features on deposition were determined to be
minimal on the regional development and local facies control of the fan.AFRIKAANSE OPSOMMING: Waaiersisteem 5 vorm die laaste submarine waaiersisteem van die Perm-ouderdom Tankwa
Waaierkompleks (Ecca Groep) in die suidwestelike Karoo-kom. Dit vorm die mees
wydverspreide sisteem en verteenwoordig ook die fmale fase van waaierafsetting in die Tankwa
sub-kom. Afsettingseienskappe verskil aansienlik van die onderliggende waaiersisteme, omdat
kenmerkende sedimentĂȘre eienskappe van 'n enkele toevoer bron ontbreek. Die hele sisteem
bestaan uit ses verskillende periodes van waaiergroei en ontwikkeling in die laer kornhelling
omgewmgs.
'n Voorspellingsmodel is opgestel vir Waaiersisteem 5 om die ruimtelike/temporele verspreiding
van die reservoir en seël fasies in kornhelling turbidiet omgewings te kan verstaan. Hierdie fasies
varieer van massiewe, geamalgameerde sandsteen tot dun gelaagde riffel- lamineerde sand- en
sliksteenlae. 'n Dik regionale skalie eenheid oorlĂȘ Waaiersisteem 5 en vorm die boonste
merkerlaag. Die basis word onderlĂȘ deur 'n 20 cm dik regionaalontwikkelde hemipelagiese
skalie laag wat die onderste merkerlaag vorm.
Ses sandige eenhede met geassosieerde kanaalkomplekse is onderskeidelik teenwoordig in: Klein
Hangklip, Groot Hangklip, Kalkgat, Tongberg, Skoorsteenberg en Blauwkop omgewings. Die
fasies-eienskappe van die mees suidelike dagsome van Waaiersisteem 5 (Tongberg, Groot
Hangklip en Kalkgat) toon afsetting in 'n laer kornhelling omgewing, waar plaaslike tektoniese
effekte moontlik 'n groot rol gespeel het in die verspreiding en regionale ontwikkeling van die
kanaalvulsels en geassosieerde oewerwal-afsettings.
Die gestapelde, wegstand kanaalvulsels-afsettings bestaan uit massiewe, geamalgameerde fyn tot
baie fynkorrelrige sandsteen eenhede, wat diktes tot ongeveer 30 m kan bereik. Dit word van
mekaar geskei deur dun sandsteenlsliksteen eenhede van afwisselende diktes. Die kanaal
komplekse in die mees proksimale dagsome word interpreteer as 'n bo-waaier, wat afgeset is in
'n laer- tot middel kornhelling omgewmg. In teenstelling met die kanaalvulsels in die
Skoorsteenberg, Klein Hangklip en Groot Hangklip omgewings, domineer riffel kruisgelamineerde
oewerwal-afsettings, geassoseer met klein kanaalvulsels, die noordoostelike en oostelike dagsome van Waaiersisteem 5. Massiewe en dungelaagde frontale plaat sandstene, kom
voor in die distale helling-omgewings in die mees noordelike dagsome van Waaiersisteem 5.
Hoogs eroderende, gestapelde kanaalkomplekse, aan die basis van die komhelling wat moontlik
beheer is deur vroeë komvloer topografie, was die oorsaak vir regionaal goed-ontwikkelde
oewerwalafsettings. Hierdie fasies-verandering vind plaas oor 'n baie kort afstand wat
betekenisvolle gevolge inhou vir die voorspelling van heterogeniteit van petroleum reservoir
fasies in komhelling afsetting-omgewings.
Die gradiënt vir die laer komhelling tot mid-komhelling omgewings is baie steiler as die distale
komvloer omgewings. Die voorkoms van sagte-sediment deformasies in die oewerwal en boliggende
dele van die kanaalvulsels weerspeël 'n moontlike komhelling omgewing. Swakontwikkelde
golfriffelmerke in die boonste lae van Waaiersisteem 5 dui 'n waterdiepte aan wat
nabyaan golf-basis is, voordat dit deur diepmariene skalies oorlĂȘ word.
Paleovloeirigtings vir Waaiersisteem 5 was in 'n noord, noordoostelike en oostelike rigting. Die
paleovloeirigting vir die Klein- en Groot Hangklip kanaalkomplekse stem min of meer ooreen
met die strukturele grein van die sinklinale laagtes in die omgewing. Die effek en beheer van
komvloer topografie en ander strukturele faktore op afsetting was minimaalop die regionale
ontwikkeling en plaaslike fasies verspreiding van die waaier