Research on pre-slaughter stress and meat quality: A review of challenges faced under practical conditions

Transportation and handling of animals are important components in meat production systems. Animals destined for slaughter are stressed by factors such as loading, transportation, restraint, handling, and novelty of the slaughter environment, adverse weather conditions, hunger, thirst and fatigue. When an animal is stressed in the pre-slaughter environment, there is a rapid release of enzymes, cortisols and catecholamines which may lead to depletion of glycogen, high meat ultimate pH (pHu) and dark cuts. Pre-slaughter stress also affects the physiology of the animal resulting in an increase in creatine kinase (CK) activity, glucose, lactate and other blood metabolites. Pre-slaughter stress and meat quality is a wide topic and some research have been done albeit was conducted under experimental and controlled conditions. In real life situations many variables are not controlled. Data collection in practical conditions is complex because it is difficult to accurately take some of the measurements; for example the onset of the release of the enzymes and hormones. Moreover, there are difficulties in taking measurements from slaughterhouses and butcheries. Challenges that researchers, marketers and consumers face under practical conditions either on-farm, research stations, transfer centres, slaughter plants, abattoirs or butcheries; with regard to pre-slaughter stress and meat quality may affect the quality of the final products developed under such conditions. This review therefore aims to give a detailed outline on pre-slaughter stress, meat science research and challenges under practical conditions

Dipole anisotropies of IRAS galaxies and the contribution of a large-scale local void

Recent observations of dipole anisotropies show that the velocity of the Local Group (\Vec v_{\rm G}) induced by the clustering of IRAS galax ies has an amplitude and direction similar to those of the velocity of Cosmic Microwave Background dipole anisotropy (\Vec v_{\rm CMB}), but the difference | \Vec v_{\rm G} - \Vec v_{\rm CMB} | is still $\sim 170$ km/s, which is about 28% of |\Vec v_{\rm CMB} |. Here we consider the possibility that the origin of this difference comes from a hypothetical large-scale local void, with which we can account for the accelerating behavior of type Ia supernovae due to the spatial inhomogeneity of the Hubble constant without dark energies and derive the constraint to the model parameters of the local void. It is found as a result that the distance between the Local Group and the center of the void must be $(10 -- 20) h^{-1}$ Mpc, whose accurate value depends on the background model parameters.Comment: 13 pages, 1 figure, to be published in ApJ 584, No.2 (2003

Reconstruction of the biogeochemistry and ecology of photoautotrophs based on the nitrogen and carbon isotopic compositions of vanadyl porphyrins from Miocene siliceous sediments

We determined both the nitrogen and carbon isotopic compositions of various vanadyl alkylporphyrins isolated from siliceous marine sediments of the Onnagawa Formation (middle Miocene, northeastern Japan) to investigate the biogeochemistry and ecology of photoautotrophs living in the paleo-ocean. The distinctive isotopic signals support the interpretations of previous works that the origin of 17-nor-deoxophylloerythroetioporphyrin (DPEP) is chlorophylls-<i>c</i><sub>1-3</sub>, whereas 8-nor-DPEP may have originated from chlorophylls-<i>a</i><sub>2</sub> or <i>b</i><sub>2</sub> or bacteriochlorophyll-<i>a</i>. Although DPEP and cycloheptanoDPEP are presumably derived from common precursory pigments, their isotopic compositions differed in the present study, suggesting that the latter represents a specific population within the photoautotrophic community. The average δ<sup>15</sup>N value for the entire photoautotrophic community is estimated to be –2 to +1‰ from the δ<sup>15</sup>N values of DPEP (–6.9 to –3.6‰; <i>n</i>=7), considering that the empirical isotopic relationships that the tetrapyrrole nuclei of chloropigments are depleted in <sup>15</sup>N by ~4.8‰ and enriched in <sup>13</sup>C by ~1.8‰ relative to the whole cells. This finding suggests that nitrogen utilized in the primary production was supplied mainly through N<sub>2</sub>-fixation by diazotrophic cyanobacteria. Based on the δ<sup>13</sup>C values of DPEP (–17.9 to –15.6‰; <i>n</i>=7), we estimated isotopic fractionation associated with photosynthetic carbon fixation to be 8–14‰. This range suggests the importance of β-carboxylation and/or active transport of the carbon substrate, indicating in turn the substantial contribution of diazotrophic cyanobacteria to primary production. Based on the δ<sup>15</sup>N values of 17-nor-DPEP (–7.4 to –2.4‰ <i>n</i>=7), the δ<sup>15</sup>N range of chlorophylls-<i>c</i>-producing algae was estimated to be –3 to +3‰. This relative depletion in sup>15</sup>N suggests that these algae mainly utilized nitrogen regenerated from diazotrophic cyanobacteria. Given that diatoms are likely to have constituted the chlorophylls-<i>c</i>-producing algae within the biogenic-silica-rich Onnagawa Formation, cyanobacteria-hosting diatoms may have been important contributors to primary production

Anomalous negative excursion of carbon isotope in organic carbon after the last Paleoproterozoic glaciation in North America

Early Paleoproterozoic time (2.5–2.0 Ga) spanned a critical phase in Earth's history, characterized by repeated glaciations and an increase in atmospheric oxygen (the Great Oxidation Event (GOE)). Following the last and most intense glaciation of this period, marine carbonates record a large positive excursion of δ^(13)C value (termed the “Lomagundi event”) between about 2.2 and 2.1 Ga coinciding with the global appearances of red beds and sulfates, which suggest an accumulation of high levels of atmospheric oxygen. Here we report the discovery of large negative excursions of δ^(13)C in organic matter (down to −55‰) from quartzose sandstones (of the Marquette Range and the Huronian Supergroups, North America) intermediate in age between the last Paleoproterozoic glaciation and the possible onset of the Lomagundi event. The negative excursion is concomitant with the appearance of intensely weathered quartzose sandstones, which may represent hot and humid conditions. There are some interpretations that potentially explain the negative excursions: (1) redeposition of older ^(13)C-depleted kerogen, (2) later post-depositional infiltration of oil, (3) active methane productions by methanogens in shallow-marine environments, or (4) dissociation of methane hydrate. If the latter two were the case, they would provide clues for understanding the environmental change connecting the intense glaciation and an increase in oxygen

Biosensor zebrafish provide new insights into potential health effects of environmental estrogens

This is the final version of the article. Available from NIEHS via the DOI in this record.BACKGROUND: Environmental estrogens alter hormone signaling in the body that can induce reproductive abnormalities in both humans and wildlife. Available testing systems for estrogens are focused on specific systems such as reproduction. Crucially, however, the potential for significant health impacts of environmental estrogen exposures on a variety of body systems may have been overlooked. OBJECTIVE: Our aim was to develop and apply a sensitive transgenic zebrafish model to assess real-time effects of environmental estrogens on signaling mechanisms in a whole body system for use in integrated health assessments. METHODS: We created a novel transgenic biosensor zebrafish containing an estrogen-inducible promoter derived with multiple tandem estrogen responsive elements (EREs) and a Gal4ff-UAS system for enhanced response sensitivity. RESULTS: Using our novel estrogen-responsive transgenic (TG) zebrafish, we identified target tissues for environmental estrogens; these tissues have very high sensitivity even at environmentally relevant concentrations. Exposure of the TG fish to estrogenic endocrine-disrupting chemicals (EDCs) induced specific expression of green fluorescent protein (GFP) in a wide variety of tissues including the liver, heart, skeletal muscle, otic vesicle, forebrain, lateral line, and ganglions, most of which have not been established previously as targets for estrogens in fish. Furthermore, we found that different EDCs induced GFP expression with different tissue response patterns and time trajectories, suggesting different potential health effects. CONCLUSION: We have developed a powerful new model for understanding toxicological effects, mechanisms, and health impacts of environmental estrogens in vertebrates

On the Canonical Reduction of Spherically Symmetric Gravity

In a thorough paper Kuchar has examined the canonical reduction of the most general action functional describing the geometrodynamics of the maximally extended Schwarzschild geometry. This reduction yields the true degrees of freedom for (vacuum) spherically symmetric general relativity. The essential technical ingredient in Kuchar's analysis is a canonical transformation to a certain chart on the gravitational phase space which features the Schwarzschild mass parameter $M_{S}$, expressed in terms of what are essentially Arnowitt-Deser-Misner variables, as a canonical coordinate. In this paper we discuss the geometric interpretation of Kuchar's canonical transformation in terms of the theory of quasilocal energy-momentum in general relativity given by Brown and York. We find Kuchar's transformation to be a ``sphere-dependent boost to the rest frame," where the ``rest frame'' is defined by vanishing quasilocal momentum. Furthermore, our formalism is general enough to cover the case of (vacuum) two-dimensional dilaton gravity. Therefore, besides reviewing Kucha\v{r}'s original work for Schwarzschild black holes from the framework of hyperbolic geometry, we present new results concerning the canonical reduction of Witten-black-hole geometrodynamics.Comment: Revtex, 35 pages, no figure

Clinical and genetic characterization of adult‐onset leukoencephalopathy with axonal spheroids and pigmented glia associated with CSF1R mutation

Background and purpose: The clinical characteristics of colony stimulating factor 1 receptor (CSF1R) related adult‐onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) have been only partially elucidated. Methods: Clinical data from CSF1R mutation carriers who had been seen at our institutions or reported elsewhere were collected and analysed using a specific investigation sheet to standardize the data. Results: In all, 122 cases from 90 families with CSF1R mutations were identified. The mean age of onset was 43 years (range 18–78 years), the mean age at death was 53 years (range 23–84 years) and the mean disease duration was 6.8 years (range 1–29 years). Women had a significantly younger age of onset than men (40 vs. 47 years, P = 0.0006, 95% confidence interval 3.158–11.177). There was an age‐dependent penetrance that was significantly different between the sexes (P = 0.0013). Motor dysfunctions were the most frequent initial symptom in women whose diseases began in their 20s. Thinning of the corpus callosum, abnormal signalling in pyramidal tracts, diffusion‐restricted lesions and calcifications in the white matter were characteristic imaging findings of ALSP. The calcifications were more frequently reported in our case series than in the literature (54% vs. 3%). Seventy‐nine per cent of the mutations were located in the distal part of the tyrosine kinase domain of CSF1R (102 cases). There were no apparent phenotype−genotype correlations. Conclusions: The characteristics of ALSP were clarified. The phenotype of ALSP caused by CSF1R mutations is affected by sex

Exo-hydrogenated Single Wall Carbon Nanotubes

An extensive first-principles study of fully exo-hydrogenated zigzag (n,0) and armchair (n,n) single wall carbon nanotubes (C$_n$H$_n$), polyhedral molecules including cubane, dodecahedrane, and C$_{60}$H$_{60}$ points to crucial differences in the electronic and atomic structures relevant to hydrogen storage and device applications. C$_n$H$_n$'s are estimated to be stable up to the radius of a (8,8) nanotube, with binding energies proportional to 1/R. Attaching a single hydrogen to any nanotube is always exothermic. Hydrogenation of zigzag nanotubes is found to be more likely than armchair nanotubes with similar radius. Our findings may have important implications for selective functionalization and finding a way of separating similar radius nanotubes from each other.Comment: 5 pages, 4 postscript figures, Revtex file, To be appear in Physical Review

Coherent, mechanical control of a single electronic spin

The ability to control and manipulate spins via electrical, magnetic and optical means has generated numerous applications in metrology and quantum information science in recent years. A promising alternative method for spin manipulation is the use of mechanical motion, where the oscillation of a mechanical resonator can be magnetically coupled to a spins magnetic dipole, which could enable scalable quantum information architectures9 and sensitive nanoscale magnetometry. To date, however, only population control of spins has been realized via classical motion of a mechanical resonator. Here, we demonstrate coherent mechanical control of an individual spin under ambient conditions using the driven motion of a mechanical resonator that is magnetically coupled to the electronic spin of a single nitrogen-vacancy (NV) color center in diamond. Coherent control of this hybrid mechanical/spin system is achieved by synchronizing pulsed spin-addressing protocols (involving optical and radiofrequency fields) to the motion of the driven oscillator, which allows coherent mechanical manipulation of both the population and phase of the spin via motion-induced Zeeman shifts of the NV spins energy. We demonstrate applications of this coherent mechanical spin-control technique to sensitive nanoscale scanning magnetometry.Comment: 6 pages, 4 figure

Duration of blood feeding of Simulium ochraceum in relation to intake of Onchocerca volvulus microfilariae

金沢大学留学生センターグアテマラにおけるオンコセルカ症の主要媒介種Simulium ochraceumのOnchocerca volvulus仔虫のとりこみに関して実験を行った。仔虫のとりこみは, ブユが体表にとまってから30秒で始まった。3∿4分後には65%のブユが吸血を完了し, とりこまれる仔虫数が最高に達した。それ以後は吸血時間がのびても, とりこみ量は増加しなかった。仔虫密度が皮膚10(mm)^2あたり55∿116匹の中程度に感染した人にあっては, とりこまれる仔虫の数は皮膚中の仔虫の密度と関連していた。しかし仔虫密度が1.8と非常に低い人の場合に, 異常に高い仔虫のとりこみが観察された。このことは, 皮膚中の仔虫密度が低い場合には, 仔虫がブユの吸血時に誘引あるいは何らかの刺激を受けることを示唆するものかもしれない。 Intake of microfilariae of Onchocerca volvulus by Simulium ochraceum, the main vector of onchocerciasis in Guatemala, was studied. The initiation of intake of microfilariae was around 30sec after landing. Thereafter, the number of microfilariae taken by flies increased as the feeding time increased. After 3 to 4min of landing, 69% of flies finished their blood meal, and the intake of microfilariae reached the highest. Thereafter, increase of feeding time did not increase the intake. With the volunteers of moderate density of microfilariae (55-116 Mf per 10(mm)^2), the number of microfilariae taken by the flies was correlated with the density of microfilariae in human skin. With a volunteer of very low density (1.8 Mf per 10(mm)^2), however, an extraordinarily high intake of microfilariae was observed. This suggested the possibility of the flies attracting or stimulating the microfilariae in the skin of low density carriers