620 research outputs found
Detection of embryo mortality and hatch using thermal differences among incubated chicken eggs
Accurate diagnosis of both the stage of embryonic mortality and the hatch process in incubated eggs is a fundamental component in troubleshooting and hatchery management. However, traditional methods disturb incubation, destroy egg samples, risk contamination, are time and labour-intensive and require specialist knowledge and training. Therefore, a new method to accurately detect embryonic mortality and hatching time would be of significant interest for the poultry industry if it could be done quickly, cheaply and be fully integrated into the process. In this study we have continuously measured individual eggshell temperatures and the corresponding micro-environmental air temperatures throughout the 21 days of incubation using standard low-cost temperature sensors. Moreover, we have quantified the thermal interaction between eggs and air by calculating thermal profile changes (temperature drop time, drop length and drop magnitude) that allowed us to detect four categories of egg status (infertile/early death, middle death, late death and hatch) during incubation. A decision tree induction classification model accurately (93.3%) predicted the status of 105 sampled eggs in comparison to the classical hatch residue breakout analyses. With this study we have provided a major contribution to the optimisation of incubation processes by introducing an alternative method for the currently practiced hatch residue breakout analyses.status: publishe
Feulgen-DNA Content and C-Banding of Robertsonian Transformed Karyotypes in Dugesia Lugubris
SUMMARYIn the planarian species, Dugesia lugubris, two biotypes are found: E (2n = 8, n = 4) and F (2n = 6, n = 3); on the basis of karyometric studies it has been hypothesized that the second was derived from the first through a Robert-sonian mechanism of centric fusion. The quantitative cytochemical data reported here confirm the hypothesis of karyotype evolution, since there are no significant differences between the DNA content of the nucleus in the two biotypes. The regenerative blastemas of both biotypes contain a number of cellular populations with a variable Feulgen-DNA content; these correspond to successive doublings of the 2C diploid content. In addition, metaphase plates with multistranded chromosomes have been found. A difference between the chromosome C-banding in the two biotypes has also been observed
EFSUMB Recommendations and Guidelines for Gastrointestinal Ultrasound - Part 1: Examination Techniques and Normal Findings (Short version)
Abstract
â–¼
In October 2014 the European Federation of Societies
for Ultrasound in Medicine and Biology formed
a Gastrointestinal Ultrasound (GIUS) task force
group to promote the use of GIUS in a clinical setting.
One of the main objectives of the task force
group was to develop clinical recommendations
and guidelines for the use of GIUS under the auspices
of EFSUMB. The first part, gives an overview of
the examination techniques for GIUS recommended
by experts in the field. It also presents the
current evidence for the interpretation of normal
sonoanatomical and physiological features as examined
with different ultrasound modalities
EFSUMB Recommendations and Guidelines for Gastrointestinal Ultrasound - Part 1: Examination Techniques and Normal Findings (Long version).
Abstract
â–¼
In October 2014 the European Federation of Societies
for Ultrasound in Medicine and Biology formed
a Gastrointestinal Ultrasound (GIUS) task force
group to promote the use of GIUS in a clinical setting.
One of the main objectives of the task force
group was to develop clinical recommendations
and guidelines for the use of GIUS under the auspices
of EFSUMB. The first part, gives an overview of
the examination techniques for GIUS recommended
by experts in the field. It also presents the
current evidence for the interpretation of normal
sonoanatomical and physiological features as examined
with different ultrasound modalities
Search for weakly interacting sub-eV particles with the OSQAR laser-based experiment: results and perspectives
Recent theoretical and experimental studies highlight the possibility of new
fundamental particle physics beyond the Standard Model that can be probed by
sub-eV energy experiments. The OSQAR photon regeneration experiment looks for
"Light Shining through a Wall" (LSW) from the quantum oscillation of optical
photons into "Weakly Interacting Sub-eV Particles" (WISPs), like axion or
axion-like particles (ALPs), in a 9 T transverse magnetic field over the
unprecedented length of m. No excess of events has been
detected over the background. The di-photon couplings of possible new light
scalar and pseudo-scalar particles can be constrained in the massless limit to
be less than GeV. These results are very close to the
most stringent laboratory constraints obtained for the coupling of ALPs to two
photons. Plans for further improving the sensitivity of the OSQAR experiment
are presented.Comment: 7 pages, 7 figure
High resolution measurements of carbon monoxide along a late Holocene Greenland ice core: evidence for in situ production
We present high-resolution measurements of carbon monoxide (CO)
concentrations from a shallow ice core of the North Greenland Eemian Ice
Drilling project (NEEM-2011-S1). An optical-feedback cavity-enhanced
absorption spectrometer (OF-CEAS) coupled to a continuous melter system
performed continuous, online analysis during a four-week measurement campaign.
This analytical setup generated stable measurements of CO concentrations
with an external precision of 7.8 ppbv (1σ), based on repeated
analyses of equivalent ice core sections. However, this first application of
this measurement technique suffered from a poorly constrained procedural
blank of 48 ± 25 ppbv and poor accuracy because an absolute
calibration was not possible. The NEEM-2011-S1 CO record spans 1800 yr and
the long-term trends within the most recent section of this record
(i.e., post 1700 AD) resemble the existing discrete CO measurements from the
Eurocore ice core. However, the CO concentration is highly variable (75–1327 ppbv
range) throughout the ice core with high frequency (annual scale), high
amplitude spikes characterizing the record. These CO signals are too abrupt
and rapid to reflect atmospheric variability and their prevalence largely
prevents interpretation of the record in terms of atmospheric CO variation.
The abrupt CO spikes are likely the result of in situ production occurring
within the ice itself, although the unlikely possibility of CO production
driven by non-photolytic, fast kinetic processes within the continuous
melter system cannot be excluded. We observe that 68% of the CO spikes
are observed in ice layers enriched with pyrogenic aerosols. Such aerosols,
originating from boreal biomass burning emissions, contain organic
compounds, which may be oxidized or photodissociated to produce CO within
the ice. However, the NEEM-2011-S1 record displays an increase of
~0.05 ppbv yr<sup>−1</sup> in baseline CO level prior to 1700 AD (129 m
depth) and the concentration remains elevated, even for ice layers depleted
in dissolved organic carbon (DOC). Thus, the processes driving the likely
in situ production of CO within the NEEM ice may involve multiple, complex
chemical pathways not all related to past fire history and require further investigation
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