bluuebunny/crossref_metadata_2025 huggingface dataset:
IntroductionAtomic and Electron Fluids
Authors: P Das Mukunda , Neilson David
Published: November 2018

This volume contains the lectures given at the fourth international Gordon Godfrey workshop held at the University of New South Wales in Sydney from 26 to 28 September 1994. This time our lecturers came from Germany, Italy, Japan, the United States and Vietnam, as well as of course from Australia. There was a total of seventeen lectures. The workshops are jointly organised by the School of Physics at the University of New South Wales and the Department of Theoretical Physics, Research School of Physical Sciences at the Australian National University and are held annually at the University of New South Wales in Sydney. Each workshop concentrates on a different and novel research area of current interest in condensed matter physics. The late Gordon Godfrey was an Associate Professor of Physics at the University of New South Wales who bequeathed his estate for the promotion and the teaching of theoretical physics within the university.
Topological Quantum Fluids
Authors: Van Hieu Nguyen
Published: November 2018

We discuss quantum-mechanical many-body systems interacting with a topological field, known as topological quantum fields. Several topics on the theory of quantum fluids are examined. First we establish the existence of topological gauge fields in high-T c superconductors and in Heisenberg quantum antiferromagnets. Then we consider typical topological quantum fluids, known as quantum Hall fluids, which are systems exhibiting the fractional quantum Hall effect (FQHE). A theoretical model of these fluids is described in detail. We also discuss the long distance physics of topological quantum fluids, their topological order parameter and possible experimental tests of the theory.
Some properties of the world crystal in fractal spacetime theory.
Authors: Agop M. , Oprea I. , Sandu C. , Vlad R. , Buzea C. Gh. , Matsuzawa H.
Published: November 2018

We prove that the wave-particle duality, inertia and the Heisenberg
uncertainty relation are properties of a fractal spacetime, self-structured by
a gravitomagnetic background field, in the world crystal.
Valence of the Elemental Transition Metals
Authors: Rose James H. , Shore Herbert B.
Published: November 2018

We propose that the recently introduced bonding valence is the appropriate
valence for describing the gross energetics of the elemental transition
metals. In support of this proposal, we show that the trends in the
experimental cohesive energies, surface energies and melting points of the
noble and transition metals are simple linear functions of the bonding
valence. The trends in the cohesive energies of the elemental transition
metals are given by 2·45ZB
– 3·47 eV, where ZB
is the bonding valence.
Bose - Einstein Condensation of Atoms with Attractive Interaction in a Harmonic Trap
Authors: Akhmediev N. , Das M. P. , Vagov A. V.
Published: November 2018

It is well known that bosonic particles with attractive interaction in a
uniform gas do not form a condensate. Here we investigate a dilute Bose gas
and study stationary solutions of the Gross–Pitaevskii equation with
attractive interaction. We have also used a higher order stabilising term in
the presence of a harmonic confining potential. We show that there are three
possible types of stationary solutions corresponding to stable, metastable and
unstable phases. These results are discussed in relation to a
7Li condensate.
Dynamical Properties of a Terahertz Driven Two-dimensional Electron Gas
Authors: Xu W.
Published: November 2018

In this paper, I present a detailed theoretical study on how a nanostructure,
such as a semiconductor-based two-dimensional electron gas (2DEG), interacts
with a linearly polarised intense laser field. A tractable method in dealing
with the time-dependent many-body problem has been developed, from which the
electron Green's function, the electron density–density correlation
function and the inverse dielectric function matrix for a 2DEG driven by
intense laser fields have been obtained. Using these results, the influence of
terahertz laser radiation on dynamical properties such as plasmon and optical
spectra in a 2DEG is investigated. The results obtained from this study can be
used for the case where the intense terahertz radiation is provided by
recently developed free-electron laser sources.
Some Experimental Prospects involving Parabolic Quantum Wells
Authors: Dobson John F. , Wang Jun , Le Hung M.
Published: November 2018

We discuss two possible lines of experimental investigation based on parabolic
quantum wells. In the first proposal, we note that the Generalised Kohn
Theorem/Harmonic Potential Theorem forbids electron–electron damping
of the Kohn mode in an electron layer gas under strictly parabolic
confinement. This applies even for very strong driving. It is therefore
interesting to attempt reduction of other sources of broadening in GaAlAs
parabolic wells, so as to achieve a prominent narrow resonance in the far
infrared. We concentrate here on phononic bandgap structures, which may be of
interest for reduction of phonon effects in other systems as well. The second
class of proposed experiment involves twinned parabolic wells in an attempt to
observe van der Waals forces directly in GaAlAs systems. In a first
approximation, the parabolic or Hooke's-law nature of the confinement
allows one to use the well as a kind of spring balance to measure the weak van
der Waals force. The influence of an applied magnetic field on these forces
appears to be significant, and this system might provide the first measurement
of such an effect.
Theory of Frictional Drag in Coupled Quantum Wells: Beyond Weak Coupling
Authors: Hu Ben Yu-Kuang
Published: November 2018

I give a brief review of the weak coupling theory of frictional drag of the
coupled quantum well. I then present a theory of frictional drag based on the
Kubo formalism that goes beyond weak coupling. Using the
T-matrix approximation, I consider the
Maki–Thompson contribution to the transconductivity and obtain a formal
result for strong-coupling frictional drag in clean Fermi liquid systems. I
discuss how the strong interlayer coupling could affect the temperature
dependence of the drag transresistivity.
Sub-Poissonian Electronic and Photonic Noise Generation in Semiconductor Junctions
Authors: Edwards Paul J.
Published: November 2018

This paper addresses sub-Poissonian electronic and photonic noise generation
in semiconductor junctions. Recent theoretical and technical advances in the
understanding and generation of quantum noise-suppressed (‘quiet’)
light have emphasised the links between photonic and electronic shot noise.
Shot-noise suppression and single electron–photon control through the
operation of the collective and single-electron Coulomb blockade mechanisms
are described.
Hormone-Phospholipid Interaction : a Possible Hormonal Mechanism of Action in the Control of Membrane Permeability
Authors: Wood A , Paleg L.G , Spotswppd T.M
Published: November 2018

Changes, proportional to the concentration of added gibberellic acid, in both width and location of
the proton resonance peak of the nine equivalent protons of the terminal methyl groups of phosphatidy1
choline (lecithin), have allowed calculation of the dissociation constant of the lecithin-gibberellic
acid complex in CDC1,. The existence of such a complex supports previous findings of an interaction
of gibberellic acid with liposomes in aqueous media.
Regulators of Cell Division in Plant Tissues. XXII* Physiological Aspects of Cytokinin-induced Radish Cotyledon Growth
Authors: Gordon M.E , Letham D.S
Published: November 2018

The cytokinin 6-benzylaminopurine (BAP) markedly stimulated the lateral expansion of excised immature radish cotyledons after a lag period of about 10 h. This growth occurred principally by cell enlargement, especially in the light which enhanced the response. However, a marked response 'to cytokinin occurred in the complete absence of red light during germination, cotyledon excision and incubation. Contact with BAP for 5 h significantly stimulated growth, but a maximum response required more than 24 h of contact; potassium chloride also promoted cotyledon expansion and acted synergistically with cytokinin.
The response to cytokinin did not appear to be mediated by ethylene, gibberellins, polyamines or cyclic nucleotides. Growth induction did not alter the respiration rate and appeared to be inde- pendent of chloroplast function.
Inhibitors of DNA and RNA synthesis and of protein synthesis on cytoplasmic ribosomes almost completely abolished BAP-induced growth, control growth being less markedly affected. There were, however, no significant BAP-induced increases in total DNA or RNA levels or specific activity before the initiation of growth stimulation. Similarly, BAP had no effect on any individual RNA species until after the lag period, when there was a small enhancement of uridine incorporation into RNA species with similar electrophoretic mobility to rRNA. Although total protein levels were not affected by BAP, the cytokinin enhanced amino acid incorporation into protein within the lag period, an effect which persisted when transcription was strongly inhibited by actinomycin D. Phosphorylation of total protein was stimulated by BAP only well after the onset of cytokinin-induced growth. Protein methylation, however, was stimulated by BAP during the lag period, and the effect was at least as early as the BAP-enhanced incorporation of methionine into protein.
The possible role of translational control in the mechanism of cytokinin action is discussed.
Pathways of CO2 Fixation in the CAM Plant Kalanchoe daigremontiana. II* Effects of O2 and CO2 Concentration on Light and Dark CO2 Fixation
Authors: Osmond C.B , Bjorkman O
Published: November 2018

Steady-state fixation of CO*2 by leaves of K. daigremontiana was examined at O*2 concentrations of 4, 20 and 36%. Oxygen concentration had no effect on the rate of dark CO*2 fixation, whereas CO*2 fixation in the light was substantially inhibited by 20 and 36% O*2. Dark CO*2 fixation showed a high affinity for CO*2 (half-saturated at about 3 �M at 16�C) whereas CO*2 fixation in the light showed a much lower affinity for CO*2 (half-saturated at about 9 �M at 16�C and 37 �M at 29�C). The inhibition by O*2 of CO*2 fixation in the light was observed at intercellular CO*2 pressures up to 850 �bar. It was associated with a positive CO*2 compensation point which was abolished in 4% O*2, and a post- illumination burst of CO*2 evolution which was not modified by low O*2. The response of dark and light CO*2 fixation in K. daigremontiana to O*2 concentration is discussed in comparison with photosynthetic CO*2 fixation in C*3 and C*4 plants.
Culture of Chlamydomonas reinhardi Protoplasts in Defined Media
Authors: Gresshoff P.M
Published: November 2018

The cell-wall-deficient mutant CW15-9 of C. veinhavdi was grown in defined medium in suspension
culture and on agar. Plating efficiencies of up to 95 % were achieved, even at low cell densities. In
suspension culture, the correlation between cell number and absorbance over a large part of the
growth cycle allowed easy monitoring of cell growth and division. Colony morphology on agar was
flat, allowing microscopic observation of individual cells. Protoplasts grown in the absence of
mannitol as an osmotic protectant did not burst, which suggests that the osmoregulation mechanism
of the wild type has been retained by CW15 cells. Algal protoplasts have advantages as a model
system for the study of higher plant protoplasts and cells in culture.
Isolation and Propeties of Chloroplasts from the Siphonous Green Alga Cualerpa simpliciuscula
Authors: Grant B.R , Howard R.J , Gayler K.R
Published: November 2018

Isolated chloroplasts fixed CO*2 and evolved oxygen at rates equal to or greater than rates measured in segments of plant frond, with a maximum hourly value of 73 �mol per mg chlorophyll (a+ b). They were equally active whether isolated in a sorbitol-based medium or in an artificial sea water medium. Their activity declined after isolation, although they were relatively resistant to lysis in hypotonic medium. The products of photosynthesis included both sucrose and alanine as well as hexose monophosphates, and organic acids. There was much less 1,3-�-glucan formation in the chloroplasts than in the intact plant fronds. These chloroplasts appeared to be free of gross contamination when seen under the light microscope, but material which could not be distinguished from cytoplasm was attached to some chloroplasts. A maximum value of 17% contamination was calculated from the distribution of the mitochondrial marker enzyme succinate dehydrogenase.
Glycine Decarboxylation in Mitochondria Isolated from Spinach Leaves
Authors: Woo K.C , Osmond C.B
Published: November 2018

Mitochondria isolated from spinach leaves contain at least two glycine decarboxylating systems. One system is stimulated by ADP and evidently couples to the electron transport chain. The other system, three times as active, is stimulated by NAD+ and oxaloacetate and is not coupled directly to electron transport; however, comparative studies with uncouplers and inhibitors indicate it may depend on a membrane potential generated by electron transport. In this system, the role of oxaloacetate appears to be the regeneration of NAD+, via mitochondrial malate dehydrogenase, as an electron acceptor during glycine decarboxylation. Mitochondria isolated from spinach leaves also catalyse a rapid glycine-dependent exchange of bicarbonate into acid-stable products. This reaction is stimulated by the addition of lipoamide dehydrogenase. The activity of the glycine decarboxylation and exchange reactions are irreversibly lost when mitochondria are broken. When corrections are applied to account for mitochondrial breakage, the rates of glycine decarboxylation and the exchange reaction are comparable to the rates of CO*2 evolution from leaves of C*3 plants in air. The role of these processes in vivo and relationship to other sources of CO*2 in the glycollate pathway are discussed.
Low-frequency Impedance of Chara coralinna: Simultaneous Measurements of the Separate Plasmalemma and Tonoplast Capacitance and Conductance
Authors: Coster H.G.L , Smith J.R
Published: November 2018

Simultaneous measurements of the separate plasmalemma and tonoplast capacitance and conductance (as a function of frequency) are described.
For frequencies > 1 Hz, the capacitance of both membranes increased with decreasing frequency. Below 1 Hz, two distinctly different types of behaviour were observed: either the membrane capacitances continued to increase, reaching values of 0.5 F/m� (50 �F/cm�) at 0.07 Hz, or the membranes became inductive at very low frequencies. At frequencies > 10 Hz, the tonoplast capacitance was 1.5-3 times higher than that of the plasmalemma and increased more rapidly with decreasing frequency. Notwithstanding this, in each case the frequency dependence of the capacitance determined from vacuolar measurements (i.e. tonoplast, cytoplasm and plasmalemma in series) was nearly the same as that of the plasmalemma alone. The conductance of the tonoplast at all frequencies was 4-10 times higher than that of the plasmalemma.
Regulation of Synthesis and Secretion of Fucose-containing Polysaccharides in Cultured Sycamore Cells
Authors: Paull R.E , Jones R.L
Published: November 2018

Regulation of the synthesis and secretion of sycamore extracellular polysaccharides (SEPS) was studied in cultured cells of Acer pseudoplatanus L. cv. Pope by monitoring the incorporation of L-[3H]fucose, a specific marker for the polysaccharide, into cell wall, soluble intracellular polysaccharide and secreted fractions. Actively growing cultures of sycamore cells produce SEPS, and it reaches a concentration in the incubation medium of up to 0.7 mg ml-� after 25 days of growth. Addition of SEPS at 10 mg ml-� to cells during the phase of active growth causes a marked and rapid inhibition of secretion of the polysaccharide into which [3H]fucose is incorporated without markedly affecting uptake of the label. Added SEPS also inhibits the incorporation of [3H]fucose into the homogenate fraction although this inhibition is less marked and requires higher concentrations of added SEPS. This inhibitory effect of SEPS can be mimicked by other charged polymers, for example polygalacturonic acid, polylysine and polyglycine, while uncharged polymers like polyethylene glycol and dextran are without effect. Furthermore, the incorporation of [3H]fucose into secreted polysaccharides of isolated protoplasts is relatively unaffected by added SEPS. We propose that SEPS and other charged polymers interact with the cell wall causing it to become impermeable to synthesized SEPS, which then accumulates between the plasmalemma and the cell wall and eventually inhibits polysaccharide synthesis.
Stomatal Metabolism: Carbon Dioxide Fixation and Labelling Patterns during Stomatal Movement in Commelina cyanea
Authors: Thorpe N , Willmer C.M , Milthorpe F.L
Published: November 2018

Epidermal strips floated on solutions with NaH14CO3 fixed 14C about three times as quickly when the stomata were opening or closing as they did when either open or closed. The proportions of the major fixation products-malate, aspartate, sugars and sugar phosphates, glycine, serine and alanine-were very similar during the opening, open and closed phases but, when closing, an appreciably higher proportion was diverted to sugars and sugar phosphates. There was a relatively greater leakage into the medium of labelled malate during the open, closed and closing phases than during opening.
Involvement of Native Abscisic Acid in the Regulation of Onset of Dormancy in Spirodela polyrrhiza
Authors: Saks Yolanta , Negbi Moshe , Ilan Israel
Published: November 2018

The medium in which an old culture of S. polyvrhiza was growing aseptically decelerated frond
multiplication and promoted turion (= dormant propagule) formation in a young culture of this
plant. The effect is attributed to abscisic acid (ABA) which had been released by the old culture
into the medium. The time of appearance of the released ABA in the solution was correlated with
the beginning of turion formation in the old culture. Native ABA is probably involved in the
regulation of onset of dormancy in S. polyrvhiza.
Development of NADH Oxidation by Red Beet Mitochondria on Slicing and Aging of The Tissues
Authors: Rayner J.R , Wiskich J.T
Published: November 2018

Mitochondria isolated from red beet slices that have been aged for 24 h or more develop a capacity
to oxidize external NADH, with oxygen as the electron acceptor. This activity is not seen with
mitochondria isolated from fresh tissue. The induced activity does not arise because an inhibitor is
eliminated or an activator is developed during the aging process. Increased NADH dehydrogenase
activity was found to be associated with both the outer and the inner membranes, but the NADH
oxidation to oxygen was associated solely with the inner membrane. The induced NADH oxidation
was insensitive to rotenone and coupled to two sites of phosphorylation. Mitochondria isolated from
aged tissue also develop some alternative oxidase activity, as judged by antimycin a- and cyanideresistant
malate oxidation, but t h ~iss less marked. The induced NADH oxidation develops in parallel
with the induced respiration of the slices of tissue. In red beet slices, the 2,4-dinitrophenol-uncoupled
respiration also increases during aging. An attempt is made to integrate the respiratory change of the
mitochondria with those of the tissue.
Movement of Potassium Ions in the Motor Tissue of Stylidium
Authors: Findlay N , Findlay G.P
Published: November 2018

In the flower of the trigger plant, Stylidium, the filaments and style are fused together into a column,
sensitive to mechanical stimulation by nectar-gathering insects. A bend ini the column at the throat
of the flower contains motor tissue of specialized anatomy, which changes curvature on stimulation,
producing a rapid angular movement (in -20 ms) of the column followed by a recovery comprising
a slow movement (in - 500 s) back to its original position and then a gradual return, within about
1 h, of its ability to again respond to stimuli. Associated with the recovery are changes in distribution
of K+ within the motor tissue. After stimulation of the column there is a net movement of K+ from
the morphologically anterior side of the column (on the convex side of the bend after the fast
movement) to the posterior side, which continues for some time after the column has returned to
its original position. The K+ then returns to the anterior side, now on the concave side of the column,
as the ability of the column to respond to stimuli is slowly regained. Under some conditions, the
column may commence oscillatory movements with a period of about 1000 s. During these oscillations
there are small oscillatory changes in the distribution of K+ within the column.
Secular Change in Mortality from Suicide in Australia during the 20th Century
Authors: Donaldson Sarah , Bi Peng , B Hiller Janet
Published: November 2018

To identify secular change in Australian suicide mortality over the period 1907-1998 and to seek possible explanations, a descriptive epidemiological study was conducted. Deaths due to suicide from 1907 to 1998 were identified according to the ICD-9. Trends in overall annual suicide mortality rates for all causes and individual causes were examined using the three-year moving average method, standardised by age and sex. Secular trends for mortality over the study period were examined in various age groups, using linear regression to test the slope. The results indicated that there has been a decline in overall age and sex standardised mortality from suicide over the study period. The death rate dropped from 15.2 per 100,000 in the early century to 13.9 per 100,000 in late century. Despite the overall decline, the female suicide mortality rates increased over the study period. Male suicide mortality rates were significantly higher than female rates over the study period (P<0.0001). Increased suicide rates were observed in the 15-24 and 25-44 year old age groups for both males and females. The group of 65+ year old females also had increased rates. Decreased rates were observed in both the male and female 45-64 year old age group and in the 65+ year old male age group. The three most common suicide methods used by males in 1907 were guns, poisoning and hanging, while for females they were drowning, hanging and poisoning. In 1998 they were changed to hanging, gas and guns for males and hanging, gas and drowning and poisoning (equally third) for females. These trends can be attributed to numerous factors such as economic crisis, world wars, the availability of suicide methods, a person's gender.
The Dietary, Physical Activity and Sedentary Behaviours of Victorian Regional Secondary School Students
Authors: Vaughan Clare , Kilkkinen Annamari , Heistaro Sami , Laatikainen Tiina , Dunbar James
Published: November 2018

The aim of this study was to investigate the dietary, physical activity and sedentary behaviours of adolescents from four secondary schools in Warrnambool, regional Victoria. In 2004, a random sample of students (n=712), stratified by school year level, was generated from school enrolment databases and 443 students completed a lifestyle questionnaire. Twenty per cent of students were physically active for 60 minutes or more per day; 28 per cent used electronic media in free time for a maximum of two hours per day. Only seven per cent of students met these two Australian physical activity recommendations. Fruit, vegetables and dairy products were consumed every day by 39 per cent, 40 per cent and 71 per cent of students respectively; three serves per day of each of these foods are recommended for Australian adolescents. Compared with boys, girls were less physically active (p<0.001), consumed more fruit (p=0.011) and vegetables (p<0.001), but fewer dairy products (p<0.024). Seventeen per cent of students were overweight or obese; these students were less physically active than normal weight peers (p<0.018). The dietary, physical and sedentary behaviours of regional Victorian secondary school students in this study were inadequate when compared with Australian recommendations. Dietary and physical activity habits are still evolving in adolescence and unhealthy habits can still be changed.
Pastoral Care in Hospital: An Overview of Issues
Authors: Barletta John , Witteveen Kate
Published: November 2018

The benefits of a holistic approach to health care include positive outcomes for patients and financial benefits for hospitals and the community. Traditionally, holistic health care incorporated only physical, psychological and social needs of patients and excluded spiritual and religious aspects. This trend has changed in recent years with health care experiencing the integrated work of chaplains, pastoral carers and spiritual carers. As evidence supports a positive relationship between religious/spiritual involvement and physical/mental health outcomes, this development is indeed worthwhile. This literature review explores issues of spiritual care, pastoral care and chaplaincy and the relationship to quality patient care within a context of holistic health care.
Negative impact of endocrine-disrupting compounds on human reproductive health
Authors: Balabanič Damjan , Rupnik Marjan , Klemenčič Aleksandra Krivograd
Published: November 2018

There is increasing concern about chemical pollutants that are able to mimic hormones, the so-called endocrine-disrupting compounds (EDCs), because of their structural similarity to endogenous hormones, their ability to interact with hormone transport proteins or because of their potential to disrupt hormone metabolic pathways. Thus, the effects of endogenous hormones can be mimicked or, in some cases, completely blocked. A substantial number of environmental pollutants, such as polychlorinated biphenyls, dioxins, polycyclic aromatic hydrocarbons, phthalates, bisphenol A, pesticides, alkylphenols and heavy metals (arsenic, cadmium, lead, mercury), have been shown to disrupt endocrine function. These compounds can cause reproductive problems by decreasing sperm count and quality, increasing the number of testicular germ cells and causing male breast cancer, cryptorchidism, hypospadias, miscarriages, endometriosis, impaired fertility, irregularities of the menstrual cycle, and infertility. Although EDCs may be released into the environment in different ways, the main sources is industrial waste water. The present paper critically reviews the current knowledge of the impact of EDCs on reproductive disorders in humans.
Sperm genome cloning used in biparental bovine embryo reconstruction
Authors: Vichera Gabriel , Olivera Ramiro , Sipowicz Pablo , Radrizzani Martín , Salamone Daniel
Published: November 2018

The generation of androgenetic haploid embryos enables several haploid blastomeres to be obtained as identical copies of a single spermatozoon genome. In the present study, we compared the developmental ability of bovine androgenetic haploid embryos constructed by different methods, namely IVF and intracytoplasmic sperm injection (ICSI) before and after oocyte enucleation. Once obtained, the blastomeres of these androgenetic haploid embryos were used as male genome donors to reconstruct biparental embryos by fusion with matured oocytes. To verify the cytoplasmic contribution of androgenetic haploid blastomeres, we used spermatozoa incubated previously with exogenous DNA that coded for a green fluorescent protein gene (pCX-EGFP) and the enhanced green fluorescent protein (EGFP)-positive androgenetic haploid blastomeres generated were fused with mature oocytes. Of the reconstructed embryos reaching the cleavage and blastocyst stages, 85.1% and 9.0%, respectively, expressed EGFP (P > 0.05). EGFP expression was observed in 100% of reconstructed embryos, with 91.2% exhibiting homogenic expression. To confirm sperm genome incorporation, androgenetic haploid blastomeres generated by ICSI prior to enucleation and using Y chromosome sexed spermatozoa were used for biparental embryo reconstruction. Incorporation of the Y chromosome was confirmed by polymerase chain reaction and fluorescence in situ hybridisation analysis. In conclusion, the results of the present study prove that it is possible to use sperm genome replicates to reconstruct biparental bovine embryos and that it is a highly efficient technique to generate homogeneous transgene-expressing embryos.
Paternal priming of maternal tissues to optimise pregnancy success
Authors: Bromfield John J. , Rizo Jason A. , Ibrahim Laila A.
Published: November 2018

The question of ‘how does the allogeneic fetus survive gestation in the face of the maternal immune system?’ has yet to be definitively answered. Several acceptable mechanisms exist to facilitate survival of the semi-allogeneic fetus in various species; paramount is the immunological separation of maternal and fetal tissues during gestation. However, keen observation of the maternal immune system during pregnancy has noted maternal immune tolerance to paternal-specific antigens. A mechanism by which the maternal immune system tolerates specific paternal antigens expressed on the fetus would be far more beneficial than the previously proposed immune indolence that would leave the mother susceptible to infection. In species like human or rodent, implantation occurs days after fertilisation and, as such, the mechanisms to establish antigen-specific tolerance must be initiated very early during pregnancy. We and others propose that these mechanisms are initiated at the time of insemination when paternal antigens are first introduced to the maternal immune system. Indeed, a new paradigm demonstrating the importance of paternal–maternal communication at the time of insemination is becoming evident as it relates to maternal tolerance to fetal antigen and ultimately pregnancy success.
A journey through horse cloning
Authors: Gambini Andrés , Maserati Marc
Published: November 2018

Interest in equine somatic cell nuclear transfer technology has increased significantly since the first equid clones were produced in 2003. This is demonstrated by the multiple commercial equine cloning companies having produced numerous cloned equids to date; worldwide, more than 370 cloned horses have been produced in at least six different countries. Equine cloning can be performed using several different approaches, each with different rates of success. In this review we cover the history and applications of equine cloning and summarise the major scientific advances in the development of this technology in horses. We explain the advantages and disadvantages of different procedures to produce cloned equine embryos and describe the current status of equine clone commercialisation, along with observations of differences in regional breed association registration regulations.
Transcriptional and epigenetic control of cell fate decisions in early embryos
Authors: Alberio Ramiro
Published: November 2018

Mammalian embryo development is characterised by regulative mechanisms of lineage segregation and cell specification. A combination of carefully orchestrated gene expression networks, signalling pathways and epigenetic marks defines specific developmental stages that can now be resolved at the single-cell level. These new ways to depict developmental processes have the potential to provide answers to unresolved questions on how lineage allocation and cell fate decisions are made during embryogenesis. Over the past few years, a flurry of studies reporting detailed single-cell transcription profiles in early embryos has complemented observations acquired using live cell imaging following gene editing techniques to manipulate specific genes. The adoption of this newly available toolkit is reshaping how researchers are designing experiments and how they view animal development. This review presents an overview of the current knowledge on lineage segregation and cell specification in mammals, and discusses some of the outstanding questions that current technological advances can help scientists address, like never before.
Fertility and the transition dairy cow
Authors: Roche J. R. , Burke C. R. , Crookenden M. A. , Heiser A. , Loor J. L. , Meier S. , Mitchell M. D. , Phyn C. V. C. , Turner S.-A.
Published: November 2018

The transition from pregnancy to lactation (i.e. the transition period) is a time of significant metabolic challenge, with a several-fold increase in a cow’s requirement for energy, protein and minerals within days of calving. A successful transition involves the initiation and coordination of changes in multiple tissues that facilitate the provision of these nutrients to the cow and, more specifically, to the mammary gland, often at the considerable expense of other tissues. Failure to coordinate the necessary changes effectively results in transition period maladaptation, which can broadly be grouped into three categories: (1) negative energy balance and metabolic diseases associated with energy metabolism; (2) immune dysfunction and inflammation; and (3) metabolic diseases associated with mineral deficiency. Because reinitiation of ovarian activity, follicle recruitment, ovulation, fertilisation and, potentially, even maternal recognition of pregnancy and implantation occur against the backdrop of this metabolic and immunological disturbance in early lactation, the role of nutrition in ensuring a smooth transition between the pregnant and lactating state is important. In this paper we integrate recent research findings with previous knowledge of the interaction between transition cow metabolism and nutrition and reproductive outcomes, and offer new insights into key elements of successful cow management to avoid transition ‘maladaptation’ and improve pregnancy rates.
Recent advances for spermatogonial stem cell transplantation in livestock
Authors: Oatley Jon M.
Published: November 2018

At the foundation of spermatogenesis are the actions of spermatogonial stem cells (SSCs), and a remarkable feature of these cells is the capacity to regenerate spermatogenesis following transplantation into testes of a recipient male that lacks endogenous germline. This ability could be exploited in livestock production as a breeding tool to enhance genetic gain. A key element to success is derivation of culture conditions that support proliferation of SSCs to provide sufficient numbers of cells for transfer into multiple recipient males. Using methodology devised for rodent cells as a foundation, advances in culturing cattle SSCs have occurred over the past few years and efforts are underway to extend this capability to pig cells. Another critical component to SSC transplantation is generation of males with germline ablation but intact somatic support cell function that can serve as surrogate sires for donor-derived spermatogenesis in a natural mating scheme. Recent advances in pigs using gene editing technologies have demonstrated that knockout of a key male germ cell-specific gene, namely NANOS2, leads to male-specific germline ablation but otherwise normal physiology, including intact seminiferous tubules. Together with recent advances in culturing spermatogonia of higher-order mammals, the now efficient means of producing germline-ablated recipient males have brought the application of SSC transplantation in livestock as a production tool closer to reality than ever before.
Erratum to: 4 INFLUENCE OF A MATERNAL DIABETES MELLITUS TYPE 1 ON LIPID AND CHOLESTEROL METABOLISM IN RABBIT PRE-IMPLANTATION EMBRYOS
Authors: Schindler M. , Pendzialek M. , Plösch T. , Knelangen J. M. , Gürke J. , Hauke E. , Fischer B. , Navarrete Santos A.
Published: November 2018

The incidence of overweight and obesity has reached epidemic levels worldwide. Even more alarming is the increasing prevalence of metabolic diseases in younger children and adolescents. The rate of women with diabetes mellitus in child-bearing age is rising, too. According to the developmental origins of health and disease (DOHaD) paradigm, exposure to a hyperglycaemic environment in utero may programme physiology and metabolism permanently, with long-term consequences for offspring health. Experimental evidence indicates that programming of obesity does occur during early embryo development, a period where many women are unaware of pregnancy. To study effects of maternal diabetes mellitus on early embryo development, we induced a type I diabetes through alloxan treatment of female rabbits. In diabetic rabbits, the triglyceride and cholesterol concentrations were altered in serum and the cholesterol concentration in the uterine secretions was elevated. Lipid content of 6-day-old blastocysts was analysed after Oil Red staining and whole mount histochemistry or with Nile Red by fluorescence-activated cell sorting (FACS). Analysis by FACS revealed an approximately 2-fold increase in lipid droplets in blastocysts grown under diabetic conditions. The expression of genes important for lipid metabolism, such as fatty acid transport protein 4 (FATP4), fatty acid-binding protein 4 (FABP4), carnitine palmitoyltransferase 1 (CPT-1), and lipoprotein lipase (LPL), were determined by real-time PCR and showed distinct differences between diabetic and control blastocysts. Immunohistochemical staining of FABP4 was clearly increased in blastocysts grown under diabetic conditions and showed a cell lineage-specific distribution. Two transcription factors, peroxisome proliferator-activated receptor α (PPARα) and PPARγ, with key functions in lipid metabolism and adipogenic differentiation, were increased in blastocysts from diabetic rabbits. We show that maternal diabetes mellitus leads to alteration in lipid metabolism and to triglyceride accumulation in blastocysts. Its long-lasting consequences (e.g. for adipose cell differentiation) need attention and further investigation.
125 Effect of Complexed Trace Minerals on Oocyte and Embryo Production
Authors: Dantas F. G. , Filho R. V. O. , Carvalho R. S. , Franco G. A. , Reese S. T. , Abbott C. R. , Payton R. R. , Edwards J. L. , Smith J. K. , Russell J. R. , Pohler K. G.
Published: November 2018

The objective of this experiment was to evaluate the impact of trace mineral supplementation on reproductive performance in lactating beef cows. Thirty days before AI (Day –30), 68 postpartum cows were stratified by weight, body condition score, and parity before being equally and randomly assigned to either a treatment or a control group. Each group received a weekly mineral supplement allotment of 1.2 kg/week per cow-calf pair for 15 weeks. Cows in the treatment group received a mineral supplement that contained zinc, copper, and manganese amino acid complexes as well as cobalt glucoheptonate (Availa® Plus; Zinpro Corp., Eden Prairie, MN, USA), whereas cows assigned to the control group received a mineral supplement that contained the same concentrations of these trace minerals from inorganic sources. All cows were submitted to a 7-day CO-Synch + CIDR protocol on Day –10 and bred using fixed time AI on Day 0. Pregnancy diagnosis was performed via transrectal ultrasound on Day 28. Cows diagnosed as nonpregnant were then removed from the experiment. Pregnant cows were divided into 10 groups of 3 or 4 cows per group: 5 treatment groups (20 total cows) and 5 control groups (18 total cows). On Day 52 and 67, all pregnant cows were subjected to an ovum pick-up (OPU). Collected oocytes were evaluated before performing in vitro fertilization. Number of oocytes cleaving (dividing into more than one cell) and developing to blastocyst stage was recorded. Analysis of variance was conducted using PROC GLIMMIX (SAS 9.4; SAS Institute Inc., Cary, NC, USA) to determine differences between treatment and control, and group was the experimental unit. Mineral consumption did not differ (P = 0.48) between treatments (average of 1.16 ± 0.065 v. 1.09 ± 0.065 kg/week per cow-calf pair, for treatment and control, respectively). Pregnancy per AI was numerically higher in mineral-supplemented cows versus controls (64.7% v. 52.9%, respectively; P = 0.33). Consumption of the complexed trace mineral supplement increased (P = 0.06) total oocyte yield (22.6 ± 1.44 mean ± SEM v. 16.4 ± 2.04 oocytes/group for treatment and control, respectively). Moreover, groups receiving the complexed trace minerals had more (P = 0.05) culturable oocytes (grades A through C) compared with control groups (15.9 ± 1.6 mean ± SEM v. 11.8 ± 1.01 oocytes/group, respectively). In addition, production of transferable embryos (grades 1 through 3) was greater (P = 0.04) for groups receiving complexed trace minerals than inorganic trace minerals (4.2 ± 0.64 mean ± SEM v. 2.6 ± 0.65 embryos/group, respectively). In summary, supplementing with zinc, manganese, and copper amino acid complexes plus cobalt glucoheptonate improved oocyte production and embryo development in pregnant beef cows when compared with cows supplemented with inorganic forms of these trace minerals.
127 L-Carnitine Supplementation During In Vitro Maturation Improves Developmental Competence of Canine Oocytes
Authors: Salama A. , Fathi M. , Badr M. R. , Moawad A. R.
Published: November 2018

In vitro embryo production (IVP) in the domestic bitch is important for conservation of endangered canids. Compared with various domestic animals, the development of assisted reproductive technologies (ART) in the dog has lagged behind, mainly due to the low percentage of oocytes that can reach metaphase II (MII) stage after in vitro maturation (IVM). Beneficial effects of l-carnitine (LC) on embryonic development in culture have been reported in many mammalian species; however, no studies have been conducted in dogs. The aim of the present study was to investigate the effect of LC supplementation during IVM of canine oocytes on nuclear maturation, fertilization status, and pre-implantation development following IVM/IVF. Cumulus-oocyte complexes (COC) were collected by slicing ovaries obtained from dogs (n = 20, 1 to 6 years of age) after ovariohysterectomy. The COC were subjected to IVM for 72 h in a medium (TCM-199) supplemented with LC at different concentrations (0.1, 0.3, 0.6, 1.0, or 2.0 mg mL−1) or without LC supplements (0 mg mL−1; control). Matured oocytes were fertilized in vitro with frozen–thawed spermatozoa, and presumptive zygotes were cultured in SOF medium for 7 days. Frequencies of nuclear maturation (72 h post-IVM), fertilization rates (18 h post-insemination), and embryo development (Days 2 to 5 post-insemination) were evaluated. Data were analysed by one-way ANOVA followed by Tukey’s multiple comparisons test. Supplementation of IVM medium with 0.3 or 0.6 mg mL−1 LC significantly improved (P ≤ 0.05) maturation (35.4% and 41.4%) and fertilization (21.3% and 25.8%) rates compared with the controls and with other LC-supplemented groups; values ranged from 20.1% to 25.0% for maturation and from 12.1% to 14.6% for fertilization. Cleavage (2- to 16-cell stages) was significantly higher (P ≤ 0.05) in the 0.6 mg mL−1 LC supplemented group than the 0.3 mg mL−1 supplemented group (16.3% v. 13.3%). These values were significantly higher (P ≤ 0.05) than those in other groups. Interestingly, 4.5% of IVM/IVF oocytes were developed to morula in 0.6 mg mL−1 LC supplemented group which was significantly higher (P ≤ 0.05) than those developed in the 0.3 mg mL−1 supplemented group (1.0%). No embryos developed beyond the 2- to 16-cell stage in the rest of the groups. In conclusion, l-carnitine supplementation during IVM is particularly efficient in improving nuclear maturation and pre-implantation embryo development of canine oocytes after IVF. These outcomes are important for the improvement of IVM conditions that can advance the efficiency of ART in dogs.
179 Xenogeneic and Allogeneic Mesenchymal Stem Cell Transplantation for Treatment of Tibial Bone Fracture in Mice
Authors: Bajwa K. K. , Sharma V. , Saini S. , Kumar A. , Thakur A. , De S. , Kumar S. , Malakar D.
Published: November 2018

Among stem cells, mesenchymal stem cells (MSC) are best suited for therapeutic purposes because of their immunomodulatory properties, ability to be isolated from adult animal at any stage, ease of propagation in the laboratory, and so on. The present study was carried out to isolate and characterise MSC from adipose tissue of mouse (Mus musculus), and to test their application for the treatment of fractured tibia bone in mouse. Cattle and buffalo MSC, already cultured and characterised in our laboratory, were used in the present study as xenogeneic MSC to observe the healing in mouse model. Murine Ad-MSC were isolated from mouse inguinal fat pad by enzymatic digestion method and cultured in growth enriching medium in standard culture conditions. To test the therapeutic potential of MSC, 24 mice were divided into 4 groups: control (C), allogeneic (A), cattle xenogeneic (CX), and buffalo xenogeneic (BX) with 6 mice (having tibial bone mechanical fractured) in each group, and had the corresponding MSC cells injected in the fracture area. The control group was not subjected to any kind of MSC treatment. Post-treatment, healing in all groups was examined for 36 days at different intervals (Days 1, 12, 24, and 36) via digital X-ray imaging. A bone healing score was assigned to each mouse per the protocol provided by RUST (Radiographic Union Scale in Tibial bone) fractures. The results of present study showed that murine Ad-MSC were positive for MSC-specific markers CD44, CD90, CD105, and negative for CD34 and CD45 via RT-PCR and immunocytochemistry. The Ad-MSC were also positive for the alkaline phosphatase staining. Statistical analysis, using Proc GLM (SAS Institute Inc., Cary, NC, USA), revealed that the bone healing was significantly different (P < 0.01) between group C (1.708 ± 0.059) and other groups [group A (2.125 ± 0.061), CX (2.167 ± 0.068), BX (2.250 ± 0.068)], suggesting that healing was greater in groups transplanted with MSC compared with control. However, healing between groups transplanted with MSC (A, CX, and BX) was not significantly different (P > 0.05). In conclusion, we have observed the healing potential of MSC in mouse model via allogeneic and xenogeneic MSC transplantation; the healing potential among the A, CX, and BX MSC groups was similar.