z+: Neutron cross section separation from wide-angle uniaxial polarization analysis.

We introduce a simple method to extract the nuclear coherent and isotope incoherent, spin incoherent, and magnetic neutron scattering cross section components from powder scattering data measured using a single neutron beam polarization direction and a position-sensitive detector with large out-of-plane coverage. The method draws inspiration from polarized small-angle neutron scattering and contrasts with conventional so-called "xyz" polarization analysis on wide-angle instruments, which requires measurements with three orthogonal polarization directions. The viability of the method is demonstrated on both simulated and experimental data for the classical "spin ice" system Ho2Ti2O7, the latter from the LET direct geometry spectrometer at the ISIS facility. The cross section components can be reproduced with good fidelity by either fitting the out-of-plane angle dependence around a Debye-Scherrer cone or grouping the data by angle and performing a matrix inversion. The limitations of the method and its practical uses are discussed.

Rare-earth thin films and superlattices.

This paper reviews neutron and x-ray diffraction studies of the magnetism of rare-earth thin films and superlattices grown using the LaMBE Facility in Oxford. Epitaxial strain is found to change the magnetic ordering and surface effects are shown to alter the critical exponents for phase transitions. The magnetic coherence across spacer layers is found to depend on the band structure of the superlattice as a whole, and the conduction-electron spin-density wave responsible for interlayer magnetic coupling is measured directly.

Effect of subclinical and clinical hypocalcemia and dietary cation-anion difference on rumination activity in periparturient dairy cows.

Rumination involves a complex series of muscle contractions that bring a bolus of ingesta to the mouth for further mastication before it is swallowed again. Healthy cows ruminate 8 to 9 h/d. Hypocalcemia is known to disrupt nerve and muscle function. Our hypothesis was that hypocalcemia in periparturient cows would reduce rumination activity. Twenty-six Holstein cows entering their third lactation or greater were fed a control diet [dietary cation-anion difference (DCAD) = +196 mEq/kg of dry matter (DM)] or a low DCAD diet supplemented with anions (DCAD = -9 mEq/kg of DM) prepartum. Periparturient plasma Ca concentration and rumination rate were determined. Four of 12 control cows developed clinical milk fever, necessitating intravenous Ca therapy. Rumination rate decreased in all cows around the time of calving. Rumination rate on the first and second day of lactation was highly correlated with the cow's plasma Ca concentration on the first day of lactation. In one of our statistical models, a normocalcemic cow was defined as a cow whose plasma Ca concentration remained above 2.00 mM. Cows were retrospectively classified as normocalcemic, subclinically hypocalcemic, or clinically hypocalcemic (milk fever). Only 4 cows were considered normocalcemic, and all had been fed the low DCAD diet. Normocalcemic cows spent more time ruminating on the first day after calving than subclinically hypocalcemic cows or cows with milk fever. Cows with milk fever had a lower rumination rate than normocalcemic cows through d 3 of lactation. Rumination activity in cows with milk fever was almost nondetectable in the hours before and after intravenous Ca treatment for an extended period, despite the return of muscle function that allowed the cows to stand and eructate following treatment. Other statistical models using different definitions of normocalcemia gave qualitatively similar results. Diet had a great effect on plasma Ca concentration and rumination rate. Even when cows with clinical milk fever were removed from the control cow data set, cows on the low DCAD diet had significantly greater plasma Ca concentrations in the first 36 h after calving and a higher rumination rate on d 1 of lactation (248 ± 26 min) than control cows (158 ± 32 min).

Targeting 1,25(OH)2D-mediated calcium absorption machinery in proximal colon with calcitriol glycosides and glucuronides.

High intestinal calcium (Ca) absorption efficiency is associated with high peak bone mass in adolescents and reduced bone loss in adulthood. Transepithelial intestinal Ca absorption is mediated by 1,25-dihydroxyvitamin D (1,25(OH)2D, calcitriol) through the vitamin D receptor (VDR). Most research on Ca absorption focuses on the proximal small intestine but evidence shows that large intestine plays a crucial role in whole body Ca homeostasis. We directly assessed and compared Ca absorption capacity at the proximal colon and duodenum using in situ ligated loops (2 mM Ca, 10 min). In C57BL/6 J mice, the proximal colon (26.2 ±â€¯3.7 %) had comparable ability to absorb Ca as the duodenum (30.0 ±â€¯6.7 %). In VDR knockout (KO) mice, Ca absorption efficiency was reduced by 67 % in duodenum and 48 % in proximal colon. These data suggest that large intestine could be targeted to improve Ca absorption and protect bone in at risk-groups (e.g. bariatric patients). Glycoside forms of calcitriol found in Solanum Glaucophyllum (Sg) leaf are biologically inert but can be activated in the colon upon bacterial cleavage of the glycosides. We conducted a study to test whether Sg leaf, as well as a novel, synthetic 1,3-diglucuronide form of calcitriol (1,3-diG) could target the proximal colon and upregulate genes involved in Ca absorption (i.e. Trpv6, S100g). 13-week-old female C57BL6/J mice were fed AIN93 G diet containing increasing levels of one of the two compounds for 2 weeks (delivering 0, 0.25, 0.5, 1, or 2 ng calcitriol equivalent per day). Both compounds induced a dose-dependent upregulation of Cyp24a1 and Trpv6 gene expression in the proximal colon. 1,3-diG also induced S100g gene expression in the proximal colon. Duodenal expression of Trpv6 was upregulated at higher doses of 1,3-diG but not Sg leaf. These data suggest that both glycosylated and glucuronidated calcitriol could be used to target the proximal colon but that dosing must be optimized to limit systemic effects that could cause hypercalcemia. Future studies will test the translational potential of these compounds to determine if they can increase Ca absorption at proximal colon and whether this can help protect bone.

Role of defects in determining the magnetic ground state of ytterbium titanate.

Pyrochlore systems are ideally suited to the exploration of geometrical frustration in three dimensions, and their rich phenomenology encompasses topological order and fractional excitations. Classical spin ices provide the first context in which it is possible to control emergent magnetic monopoles, and anisotropic exchange leads to even richer behaviour associated with large quantum fluctuations. Whether the magnetic ground state of Yb2Ti2O7 is a quantum spin liquid or a ferromagnetic phase induced by a Higgs transition appears to be sample dependent. Here we have determined the role of structural defects on the magnetic ground state via the diffuse scattering of neutrons. We find that oxygen vacancies stabilise the spin liquid phase and the stuffing of Ti sites by Yb suppresses it. Samples in which the oxygen vacancies have been eliminated by annealing in oxygen exhibit a transition to a ferromagnetic phase, and this is the true magnetic ground state.

Effect of diets containing sulfate or chloride-based anionic salts, fed to grazing prepartum dairy cows, on concentrations of Ca in plasma, disease incidence and milk yield.

AIMS: To compare the effect of two partial mixed ration diets containing either sulfate or chloride-based anionic salts, fed to grazing prepartum dairy cows, on concentrations of Ca, Mg, P and beta-hydroxybutyrate (BHB) in plasma, disease incidence and milk yield during the early postpartum period. METHODS: The study was conducted on a seasonal-calving grazing dairy farm located in Benton (MO, USA). In August 2016, two groups of 200 cows were randomly assigned at 30 days before expected parturition to receive either a sulfate or chloride-based anionic diet, to achieve a dietary cation-anion difference (DCAD) of -25 mEq/kg DM. Cows were fed partial mixed rations to provide 50% of their DM intake, with 50% provided by grazing fescue pasture. Urine samples were collected from 20 cows from each group once a week for 5 weeks until calving for pH assessment. At parturition, 42 cows per group were selected at random and blood samples collected on Days 1, 2, 3 and 7 postpartum. The study continued until 100 cows per group calved. Health events and cumulative milk yield until 30 days postpartum were recorded. Concentrations of Ca, P, and Mg in plasma at Days 1, 2, 3, and 7, and BHB in plasma at Day 7 postpartum were assessed. RESULTS: Mean urine pH was lower in cows in the chloride than sulfate group (p≤0.06) on four of five sampling occasions. Mean concentrations of Ca in plasma on Day 1 were 2.00 (95% CI=1.94-2.05) and 1.91 (95% CI=1.88-1.97) mmol/L for the chloride and sulfate groups, respectively (p=0.15), and on Day 3 were 2.03 (95% CI=1.97-2.08) and 1.90 (95% CI=1.84-1.96) mmol/L, respectively (p=0.038). Concentrations of Mg, P and BHB in plasma and incidence of diseases postpartum were similar in both groups (p>0.05). There were no cases of clinical hypocalcaemia in either group. CONCLUSIONS AND CLINICAL RELEVANCE: Prepartum cows fed a partial mixed ration with a negative DCAD containing chloride-based anionic salts and free access to a fescue pasture had lower prepartum urine pH, and higher concentrations of total Ca in plasma during the first week postpartum, than cows receiving a partial mixed ration containing sulfate-based anionic salts.

Diffusion mechanism in the sodium-ion battery material sodium cobaltate.

High performance batteries based on the movement of Li ions in Li x CoO2 have made possible a revolution in mobile electronic technology, from laptops to mobile phones. However, the scarcity of Li and the demand for energy storage for renewables has led to intense interest in Na-ion batteries, including structurally-related Na x CoO2. Here we have determined the diffusion mechanism for Na0.8CoO2 using diffuse x-ray scattering, quasi-elastic neutron scattering and ab-initio molecular dynamics simulations, and we find that the sodium ordering provides diffusion pathways and governs the diffusion rate. Above T ~ 290 K the so-called partially disordered stripe superstructure provides channels for quasi-1D diffusion, and melting of the sodium ordering leads to 2D superionic diffusion above T ~ 370 K. We obtain quantitative agreement between our microscopic study of the hopping mechanism and bulk self-diffusion measurements. Our approach can be applied widely to other Na- or Li-ion battery materials.

Hopping Time Scales and the Phonon-Liquid Electron-Crystal Picture in Thermoelectric Copper Selenide.

The suppression of transverse phonons by liquidlike diffusion in superionic conductors has been proposed as a means to dramatically reduce thermal conductivity in thermoelectric materials [H. Lui et al. Nat. Mater. 11, 422 (2012)NMAACR1476-112210.1038/nmat3273]. We have measured the ion transport and lattice dynamics in the original phonon-liquid electron-crystal Cu_{2}Se using neutron spectroscopy. We show that hopping time scales are too slow to significantly affect lattice vibrations and that the transverse phonons persist at all temperatures. Substantial changes to the phonon spectrum occur well below the transition to the superionic phase, and the ultralow thermal conductivity is instead attributed to anharmonicity.

Downregulation of estrogen receptor and modulation of growth of breast cancer cell lines mediated by paracrine stromal cell signals.

PURPOSE: Breast cancers have a poorer prognosis if estrogen receptor expression was lost during recurrence. It is unclear whether this conversion is cell autonomous or whether it can be promoted by the microenvironment during cancer dormancy. We explored the ability of marrow-derived stromal cell lines to arrest co-cultured breast cancer cells and suppress estrogen receptor alpha (ER) expression during arrest, facilitating the emergence of estrogen-independent breast cancer clones. METHODS: Cancer cell growth, ER protein, microRNA, and mRNA levels were measured in breast cancer cell lines exposed to conditioned medium from marrow stromal lines in the presence and absence of estrogen and of signaling pathway modulators. RESULTS: We demonstrate that paracrine signaling from the stromal cell line HS5 downregulated ER in T47D and MCF7 breast cancer cells. This occurred at the mRNA level and also through decreased ER protein stability. Additionally, conditioned medium (CM) from HS5 arrested the breast cancer cells in G0/G1 in part through interleukin-1 (IL1) and inhibited cancer cell growth despite the activation of proliferative pathways (Erk and AKT) by the CM. Similar findings were observed for CM from the hFOB 1.19 osteoblastic cell line but not from two other fibroblastic marrow lines, HS27A and KM101. HS5-CM inhibition of MCF7 proliferation could not be restored by exogenous ER, but was restored by the IL1-antagonist IL1RA. In the presence of IL1RA, HS5-CM activation of AKT and Erk enabled the outgrowth of breast cancer cells with suppressed ER that were fulvestrant-resistant and estrogen-independent. CONCLUSIONS: We conclude that marrow-derived stromal cells can destabilize estrogen receptor protein to convert the ER status of growth-arrested ER+ breast cancer cell lines. The balance between stromal pro- and anti-proliferative signals controlled the switch from a dormant phenotype to estrogen-independent cancer cell growth.

Effect of oral mineral and energy supplementation on blood mineral concentrations, energetic and inflammatory profile, and milk yield in dairy cows affected with dystocia.

The objectives of this study were to determine the effect of mineral/energy supplementation of dairy cows with dystocia on blood mineral concentrations, energetic and inflammatory profiles, and milk yield. Multiparous Holstein cows with dystocia were randomly assigned into two groups, (1) treated with a mineral/energy supplement (DME, n= 18) and (2) not treated (DNT, n= 22). A group of cows with normal parturition were randomly selected and were left untreated (NNT, n= 25). Cows in DME received an oral drench of 110 g of calcium and 400 g of propionate as calcium propionate plus 110 g potassium chloride and 150 g of magnesium sulfate administered within 6 h of calving and again 3 days post-partum. Compared to cows with a normal parturition, dystocic cows had decreased plasma calcium concentrations, increased plasma haptoglobin, decreased milk yield at 1 day post-partum, and tended to have increased rectal temperatures from 1 to 12 days post-partum. Compared with cows in DNT, those in DME had decreased plasma calcium concentrations and increased plasma magnesium concentrations 2 and 3 days post-partum, and a tendency for an increase in rectal temperature from 1 to 12 days post-partum. Dystocia is detrimental to calcium homeostasis post-partum, but mineral/energy supplementation as undertaken in this study is not recommended for use in cows with dystocia.

Vacancy defects and monopole dynamics in oxygen-deficient pyrochlores.

The idea of magnetic monopoles in spin ice has enjoyed much success at intermediate temperatures, but at low temperatures a description in terms of monopole dynamics alone is insufficient. Recently, numerical simulations were used to argue that magnetic impurities account for this discrepancy by introducing a magnetic equivalent of residual resistance in the system. Here we propose that oxygen deficiency is the leading cause of magnetic impurities in as-grown samples, and we determine the defect structure and magnetism in Y2Ti2O7-δ using diffuse neutron scattering and magnetization measurements. These defects are eliminated by oxygen annealing. The introduction of oxygen vacancies causes Ti(4+) to transform to magnetic Ti(3+) with quenched orbital magnetism, but the concentration is anomalously low. In the spin-ice material Dy2Ti2O7 we find that the same oxygen-vacancy defects suppress moments on neighbouring rare-earth sites, and that these magnetic distortions markedly slow down the long-time monopole dynamics at sub-Kelvin temperatures.

Diet-induced pseudohypoparathyroidism: A hypocalcemia and milk fever risk factor.

Subclinical hypocalcemia may affect half of all multiparous cows, and clinical hypocalcemia or milk fever affects approximately 5% of dairy cows each year. This disorder of calcium homeostasis can be induced by several dietary factors. Recent studies implicate high dietary potassium and high dietary cation-anion difference (DCAD) with increased risk of milk fever. The hypothesis tested in this study was that high-DCAD diets fed to prepartum cows reduce tissue sensitivity to parathyroid hormone (PTH), inducing a pseudohypoparathyroid state that diminishes calcium homeostatic responses. Multiparous Jersey cows were fed low- or high-DCAD diets in late gestation, creating a compensated metabolic alkalosis in the high-DCAD cows and a compensated metabolic acidosis in the low-DCAD cows. They then received synthetic PTH injections at 3-h intervals for 48 h. Parathyroid hormone is expected to cause an increase in plasma calcium by increasing renal production of 1,25-dihydroxyvitamin D and increasing bone calcium resorption. Plasma calcium concentration increased at a significantly lower rate in cows fed the high-DCAD diet. Cows fed the high-DCAD diet also produced significantly less 1,25-dihydroxyvitamin D in response to the PTH injections than cows fed the low-DCAD diet. Serum concentrations of the bone resorption marker carboxyterminal telopeptide of type I collagen were numerically lower in cows fed the high-DCAD diet but this difference was not statistically significant. These data provide direct evidence that high-DCAD diets reduce tissue sensitivity to PTH. The metabolic alkalosis associated with high-DCAD diets likely induces a state of pseudohypoparathyroidism in some dairy cows at the onset of lactation, resulting in hypocalcemia and milk fever.

Effects of supplemental vitamin D3 on serum 25-hydroxycholecalciferol and growth of preweaning and nursery pigs.

Four experiments were conducted to investigate the effects of varying concentrations of supplemental vitamin D3 on pig growth, feed preference, serum 25-hydroxycholecalciferol [25(OH)D3] , and bone mineralization of nursing and weanling pigs. In Exp. 1, 270 pigs (1.71 ± 0.01 kg BW) were administered 1 of 3 oral vitamin D3 dosages (none, 40,000, or 80,000 IU vitamin D3) on d 1 or 2 of age. Increasing oral vitamin D3 increased serum 25(OH)D3 on d 10 and 20 (quadratic, P < 0.01) and d 30 (linear, P < 0.01). No differences were observed in ADG before weaning or for nursery ADG, ADFI, or G:F. Vitamin D3 concentration had no effect on bone ash concentration or bone histological traits evaluated on d 19 or 35. In Exp. 2, 398 barrows (initially 7 d of age) were used in a 2 × 2 split plot design to determine the influence of vitamin D3 before (none or 40,000 IU vitamin D3 in an oral dose) or after weaning (1,378 or 13,780 IU vitamin D3/kg in nursery diets from d 21 to 31 of age) in a 45-d trial. Before weaning (7 to 21 d of age), oral vitamin D3 dose did not influence growth but increased (P < 0.01) serum 25(OH)D3 at weaning (d 21) and tended (P = 0.08) to increase 25(OH)D3 on d 31. Increasing dietary vitamin D3 concentration from d 21 to 31 increased (P < 0.01) serum 25(OH)D3 on d 31. Neither the oral vitamin D3 dose nor nursery vitamin D3 supplements influenced nursery ADG, ADFI, or G:F. In Exp. 3, 864 pigs (initially 21 d of age) were allotted to 1 of 2 water solubilized vitamin D3 treatments (none or 16,516 IU/L vitamin D3 provided in the drinking water from d 0 to 10) in a 30-d study. Providing vitamin D3 increased serum 25(OH)D3 concentrations on d 10, 20, and 30; however, vitamin D3 supplementation did not affect overall (d 0 to 30) ADG, ADFI, or G:F. In Exp. 4, 72 pigs were used in a feed preference study consisting of 2 feed preference comparisons. Pigs did not differentiate diets containing either 1,378 or 13,780 IU vitamin D3/kg but consumed less (P < 0.01) of a diet containing 44,100 IU vitamin D3/kg compared with the diet containing 1,378 IU vitamin D3/kg. Overall, these studies demonstrate that supplementing vitamin D3 above basal concentrations used in these studies is effective at increasing circulating 25(OH)D3, but the supplement did not influence growth or bone mineralization. Also, concentrations of vitamin D3 of 44,100 IU/kg of the diet may negatively affect feed preference of nursery pigs.

Suppression of thermal conductivity by rattling modes in thermoelectric sodium cobaltate.

The need for both high electrical conductivity and low thermal conductivity creates a design conflict for thermoelectric systems, leading to the consideration of materials with complicated crystal structures. Rattling of ions in cages results in low thermal conductivity, but understanding the mechanism through studies of the phonon dispersion using momentum-resolved spectroscopy is made difficult by the complexity of the unit cells. We have performed inelastic X-ray and neutron scattering experiments that are in remarkable agreement with our first-principles density-functional calculations of the phonon dispersion for thermoelectric Na(0.8)CoO2, which has a large-period superstructure. We have directly observed an Einstein-like rattling mode at low energy, involving large anharmonic displacements of the sodium ions inside multi-vacancy clusters. These rattling modes suppress the thermal conductivity by a factor of six compared with vacancy-free NaCoO2. Our results will guide the design of the next generation of materials for applications in solid-state refrigerators and power recovery.

The antiferromagnetic structures of IrMn3 and their influence on exchange-bias.

We have determined the magnetic structures of single-crystal thin-films of IrMn3 for the crystallographic phases of chemically-ordered L12, and for chemically-disordered face-centred-cubic, which is the phase typically chosen for information-storage devices. For the chemically-ordered L12 thin-film, we find the same triangular magnetic structure as reported for the bulk material. We determine the magnetic structure of the chemically-disordered face-centred-cubic alloy for the first time, which differs from theoretical predictions, with magnetic moments tilted away from the crystal diagonals towards the face-planes. We study the influence of these two antiferromagnetic structures on the exchange-bias properties of an epitaxial body-centred-cubic Fe layer showing that magnetization reversal mechanism and bias-field in the ferromagnetic layer is altered significantly. We report a change of reversal mechanism from in-plane nucleation of 90° domain-walls when coupled to the newly reported cubic structure towards a rotational process, including an out-of-plane magnetization component when coupled to the L12 triangular structure.

Adaptive immunity in the colostrum-deprived calf: response to early vaccination with Mycobacterium bovis strain bacille Calmette Guerin and ovalbumin.

Responses of the newborn calf to vaccination are frequently characterized by marginal antibody (Ab) responses. The present study evaluated effects of colostrum ingestion on the adaptive immune response of the preruminant calf to early vaccination. Colostrum-fed (CF) and colostrum-deprived (CD) calves were vaccinated at 2 d of age with Mycobacterium bovis, Pasteur strain of bacille Calmette Guerin (BCG), and ovalbumin (OVA) to track development of the adaptive immune response during the first 8 wk of life. Dams were also vaccinated with BCG prepartum. At wk 0, serum IgG(1), IgG(2), IgA, and IgM were elevated in CF calves, with IgG(1) predominating. In these calves, IgG(2), IgA, and IgM concentrations decreased with age. The CD calves, in contrast, had very low or undetectable serum immunoglobulin concentrations at wk 0 followed by an age-related increase in IgG(1), IgG(2), and IgM concentrations, suggesting endogenous production of these immunoglobulin classes. Immunoblot and ELISA analyses of Ab response to BCG vaccination indicated that colostrum ingestion was associated with measurable serum anti-mycobacterial Ab in CF calves during the first month postpartum, with substantially lower levels at 7 wk of age. Although mycobacteria-specific Ab was undetectable in CD calves at wk 0, it was present at 4 and 7 wk of age, suggesting that these calves, unlike CF calves, were capable of generating an Ab response to BCG vaccination. Antibody responses of CF and CD calves to vaccination with OVA, an antigen not present in the natural environment of dairy cattle, were of comparable magnitude and characterized by a progressive increase in Ab levels from birth (wk 0) to 7 wk of age. The disparate Ab responses of CF calves to BCG and OVA suggest that maternal antigenic experience or exposure influences Ab responses of the colostrum-fed preruminant calf to early vaccination. Ex vivo, antigen [OVA and M. bovis-derived purified protein derivative (PPDb)]-induced IFN-γ and nitric oxide responses of blood mononuclear cells (PBMC) from CF and CD calves were comparable at wk 0 and wk 7. As expected, responses were very low or nonexistent at wk 0. Responses for all calves were greater at wk 7 than at wk 0, suggesting a colostrum-independent maturation of the cell-mediated immune response capacity of the preruminant calf. The consistently greater proliferative responses of antigen-stimulated T-cell subsets at wk 7 versus wk 0 indicate the development of antigen-specific lymphocyte responses to early vaccination. Total numbers of blood leukocytes as well as numbers of lymphocytes and monocytes were unaffected by colostrum feeding; however, granulocyte numbers were higher in CD than in CF calves at wk 0. Granulocyte numbers decreased and monocyte numbers increased with age in all calves. Within the lymphocyte population, only natural killer (NK(+)) cell percentages were affected by colostrum ingestion, with higher percentages of NK(+) cells in CD calves at wk 0 and wk 7. Antigen-induced proliferation of lymphocyte subsets including IgM(+) cells was unaffected by colostrum ingestion. In conclusion, ingestion of colostrum within hours after birth inhibited the capacity of the calf to produce antigen-specific immunoglobulin (i.e., antibody) in response to vaccination, with little or no effect on cell-mediated immune responses. Although colostrum appeared to block endogenous antibody production, certain B-cell functions were retained. These findings will aid in development of new vaccination strategies for improving health of the preruminant calf.

Modulation of in utero total body irradiation induced newborn mouse growth retardation by maternal manganese superoxide dismutase-plasmid liposome (MnSOD-PL) gene therapy.

To determine the effects of manganese superoxide dismutase (MnSOD) plasmid liposome (PL) maternal radioprotection on fetal mice, timed pregnant female mice (E14 gestation) were irradiated to 3.0 Gy total body irradiation (TBI) dose, and the number, weight and growth and development over 6 months after birth of newborn mice was quantitated compared with irradiated controls. Maternal MnSOD-PL treatment at E13 improved pup survival at birth (5.4±0.9 per litter) compared with non-irradiated 3.0 Gy controls 4.9±1.1. There was no statistically significant difference in newborn abnormalities, male to female ratio in newborn litters, or other evidence of teratogenesis in surviving newborn mice from MnSOD-PL treated compared with irradiated controls. However, E14 3 Gy irradiated pups from gene therapy-treated mothers showed a significant increase in both growth and overall survival over 6 months after birth (P=0.0022). To determine if transgene product crossed the placenta pregnant E13 mice were injected intravenously with hemagglutinin-epitope-tagged MnSOD (100 µg plasmid in 100 µl liposomes), then after 24 h, fetal mice, placentas and maternal tissues were removed and tested by both immunohistochemistry and reverse transcriptase-PCR for transgene and product. There was no evidence of transgene or product in placenta or any fetal tissue while maternal liver was positive by both assays. The data provide evidence for fetal radioprotection by maternal MnSOD-PL gene therapy before irradiation, which is mediated by an indirect bystander effect and is associated with a significant improvement in both survival at birth and growth and development of newborn mice.

The influence of interfacial roughness on the coherence of structure and magnetic coupling across barriers in Fe/MgO multilayers.

Single-crystal Fe/MgO multilayers are model systems in which to study magnetic tunnel junctions. We find that the interfacial roughness leads to the loss of coherence of the crystal structure. For thick MgO layers ferromagnetic (FM) ordering is found using polarized neutron reflectivity (PNR). For thin MgO layers magnetization measurements reveal the presence of antiferromagnetic (AF) interactions, but no long-range AF order is found using PNR. After cycling in a hysteresis loop, FM correlations are found at the coercive point, and this will limit the maximum tunnelling magnetoresistance.

Comparison of Holstein and Jersey innate immune responses to Escherichia coli intramammary infection.

Mastitis is one of the most prevalent diseases in cattle and remains among the most costly diseases to the dairy industry. Various surveys have indicated a greater prevalence of and risk for mastitis in Holstein cows than in Jersey cows. The innate immune system comprises the immediate host defense mechanisms that respond to infection, and differences in the magnitude and rapidity of this response are known to influence susceptibility to and clearance of infectious pathogens. The reported differences in the prevalence of mastitis between Holstein and Jersey cows may suggest the occurrence of breed-dependent differences in the innate immune response to intramammary infection. The objective of the current study was to compare the acute phase and cytokine responses of Holstein and Jersey cows following intramammary infection by the bacterial pathogen Escherichia coli, a leading cause of clinical mastitis. All cows in the study were in similar stages of lactation, of the same parity, subjected to the same housing and management conditions, and experimentally infected on the same day with the same inoculum preparation. Before and after infection, the following innate immune parameters were monitored: bacterial clearance; febrile response; induction of the acute phase proteins serum amyloid A and lipopolysaccharide-binding protein; alterations in total and differential white blood cell counts; changes in milk somatic cell counts and mammary vascular permeability; and induction of the cytokines IFN-gamma, IL-1beta, IL-8, IL-12, and tumor necrosis factor-alpha. Overall innate immune responses were similar between the 2 breeds; however, temporal differences in the onset, cessation, and duration of several responses were detected. Despite these differences, intramammary clearance of E. coli was comparable between the breeds. Together, these data demonstrate a highly conserved innate immune response of Holstein and Jersey cows to E. coli intramammary infection.