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Abstract LiCrSe2 constitutes a recent valuable addition to the ensemble of two-dimensional triangular lattice antiferromagnets. In this work, we present a comprehensive study of the low temperature nuclear and magnetic structure established in this material. Being subject to a strong magnetoelastic coupling, LiCrSe2 was found to undergo a first order structural transition from a trigonal crystal system ( $$P\bar{3}m1$$ P 3 ¯ m 1 ) to a monoclinic one (C2/m) at T s = 30 K. Such restructuring of the lattice is accompanied by a magnetic transition at T N = 30 K. Refinement of the magnetic structure with neutron diffraction data and complementary muon spin rotation analysis reveal the presence of a complex incommensurate magnetic structure with a up-up-down-down arrangement of the chromium moments with ferromagnetic double chains coupled antiferromagnetically. The spin axial vector is also modulated both in direction and modulus, resulting in a spin density wave-like order with periodic suppression of the chromium moment along the chains. This behavior is believed to appear as a result of strong competition between direct exchange antiferromagnetic and superexchange ferromagnetic couplings established between both nearest neighbor and next nearest neighbor Cr3+ ions. We finally conjecture that the resulting magnetic order is stabilized via subtle vacancy/charge order within the lithium layers, potentially causing a mix of two co-existing magnetic phases within the sample.

The mixed valence Cr ^3+ /Cr ^4+ compound NaCr _2 O _4 , hosts a plethora of unconventional electronic properties. In the present study, muon spin rotation/relaxation ( $\mu^+$ SR) and high-resolution time-of-flight neutron powder diffraction measurements were carried out on high-quality samples to clarify the complex magnetic ground state of this unique material. We identified a commensurate canted antiferromagnetic order (C-AFM) with a canting angle of the Cr spin axial vector equal to $\theta_{\mathrm{c}} = (8.8\pm0.5)^{\circ}$ , and an estimated Cr moment $\mu^{\mathrm{C}}_{\mathrm{Cr}} \sim (4.30\pm0.01)\mu_\mathrm{B}$ . Such an unusually large value of $\mu^{\mathrm{C}}_{\mathrm{Cr}}$ is compatible with the existence of high-spin Cr sites created by the presence of an unconventional negative charge transfer state in NaCr _2 O _4 . In addition to the C-AFM structure, a novel magnetic supercell was also revealed. Such supercell display an incommensurate (IC)-AFM propagation vector (0 0 ${\textstyle \frac{1}{2}-}\delta$ ), having a Cr moment $\mu^{\mathrm{IC}}_{\mathrm{Cr}} = (2.20\pm0.03)\mu_\mathrm{B}$ . It is suggested that the C-AFM and IC-AFM modulations have two different electronic origins, being due to itinerant and localized contributions to the magnetic moment respectively. Finally, the direct measurement of the magnetic order parameter for the C-AFM structure provided a value of the critical exponent $\beta = 0.245 \approx \frac{1}{4}$ , suggesting a non conventional critical behavior for the magnetic phase transition in NaCr _2 O _4 .

We previously demonstrated that nicotine elicited kinetic tremor by elevating the neural activity of the inferior olive via α7 nicotinic acetylcholine (nACh) receptors. Since α7 nACh receptors reportedly facilitate synaptic monoamine release, we explored the role of 5-HT receptors in induction and/or modulation of nicotine tremor. Treatment of mice with nicotine induced kinetic tremor that normally appeared during movement. The 5-HT1A agonist, 8-hydroxydipropylaminotetraline (8-OH-DPAT), significantly enhanced nicotine-induced tremor and the action of 8-OH-DPAT was antagonized by WAY-100135 (5-HT1A antagonist). In addition, the cerebral 5-HT depletion by repeated treatment with p-chlorophenylalanine did not reduce, but rather potentiated the facilitatory effects of 8-OH-DPAT. In contrast, the 5-HT2 agonist, 2,5-dimethoxy-4-iodoamphetamine (DOI), significantly attenuated nicotine tremor, which was antagonized by ritanserin (5-HT2 antagonist). The 5-HT3 agonist SR-57227 did not affect nicotine-induced tremor. Furthermore, when testing the direct actions of 5-HT antagonists, nicotine tremor was inhibited by WAY-100135, but was unaffected by ritanserin, ondansetron (5-HT3 antagonist) or SB-258585 (5-HT6 antagonist). These results suggest that postsynaptic 5-HT1A receptors are involved in induction of nicotine tremor mediated by α7 nACh receptors. In addition, 5-HT2 receptors have an inhibitory modulatory role in induction of nicotine tremor.

Positive- and negative-muon spin rotation and relaxation (μ^{±}SR) was first used to investigate fluctuations of nuclear magnetic fields in an olivine-type battery material, LiMnPO_{4}, in order to clarify the diffusive species, namely, to distinguish between a μ^{+} hopping among interstitial sites and Li^{+} ions diffusing in the LiMnPO_{4} lattice. Muon diffusion can only occur in μ^{+}SR, because the implanted μ^{−} forms a stable muonic atom at the lattice site, and therefore any change in linewidth measured with μ^{−}SR must be due to Li^{+} diffusion. Since the two measurements exhibit a similar increase in the field fluctuation rate with temperature above 100 K, it is confirmed that Li^{+} ions are in fact diffusing. The diffusion coefficient of Li^{+} at 300 K and its activation energy were estimated to be 1.4(3)×10^{−10}cm^{2}/s and 0.19(3) eV, respectively. Such combined μ^{±}SR measurements are thus shown to be a suitable tool for detecting ion diffusion in solid-state energy materials.

Extracapsular technique with lateral fabellar suture (LFS) is one of the commonest surgical techniques for canine cranial cruciate ligament (CRCL) rupture. Among LFS methods, parallel double holes in the tibia are the most effective for the repair of canine stifle joint. The aim of this study was to evaluate the effectiveness of two-hole LFS for canine CRCL rupture. We retrospectively evaluated the outcome of canine CRCL rupture treated with two-hole LFS technique performed by two surgeons from October 2011 to September 2013. Breeds included Beagle (n=5), Yorkshire terrier (n=5), German shepherd (n=4), and so on. Mean body weight was 14.0±11.6 kg (>10 kg: n=16, <10 kg: n=22). Body condition score (5 scales) was as follows: 1 (n=0), 2 (n=1), 3 (n=18), 4 (n=18), and 5 (n=1). There were 18 males [neutered (n=11)] and 20 females [spayed (n=12)]. Mean age was 83.4±44.8 months (>12 months: n=35, <12 months: n=3). The type of rupture was partial (n=17) and complete (n=21). The affected site was right (n=20), left (n=18), and bilateral (n=4). Rehabilitation after operation was needed in 8 cases. There were 12 cases of previous medial patellar luxation operation, and 6 cases of opposite site CRCL surgery. Start of weight bearing and resolution of extension function was on day 1 (n=30), day 2 (n=0), and after day 2 (n=8). There was no evidence of surgical site infection/inflammation in any cases. The results of this study showed that two-hole LFS is an easy and effective technique for the repair of canine CRCL. [ABSTRACT FROM AUTHOR]

Canine medial patellar luxation (MPL) is a very common orthopedic disease in small animals. Because the pathophysiology of this disease involves various pathways, the surgical techniques and results vary according to the veterinarian. Further, the landmark for block recession is not completely clear. We retrospectively evaluated 75 dogs (107 limbs) with MPL in whom our landmark for block recession was used from July 2008 to May 2013. Information regarding the breed, age, sex, body weight, body condition score (BCS), lateral vs bilateral, pre-operative grading, surgical techniques, removal of implants, concomitance with anterior cruciate ligament (ACL) rupture, re-luxation, re-operation, and rehabilitation was obtained from the medical records. The breeds were as follows: Chihuahua (n=23), Pomeranian (n=12), Yorkshire Terrier (n=9), and so on. The study group consisted of 33 males (castrated n=13) and 42 females (spayed n=21). The median age was 53.3±35.9 months (32-146 months); 13 cases were less than 12 months of age (17.3%). The pre-surgical BCSs were as follows: 1 (n=0), 2 (n=20), 3 (n=24), 4 (n=24) and 5 (n=7). The body weight was 4.51±3.48 kg (1.34-23.0 kg); 71 cases (94.7%) were less than 10 kg. The MPL grades (each limb) were G1 (n=1), G2 (n=18), G3 (n=78), and G4 (n=10); 32 cases were bilateral and 43 cases were unilateral (right n=27; left n=16). The specific surgical procedure (distal femoral osteotomy) was 3 stifles in Chihuahuas. Concurrent with ACL rupture was 16/107 stifles (15.0%) corrected with the over-the-top method or the extracapsular method in Papillons (5/6), Chihuahuas (5/23), and so on. The occurrences of re-luxation and re-operation were 3 out of 107 stifles (2.8%) and 0%, respectively. In this retrospective study, we present a potentially good surgical landmark for block recession of MPL in dogs. [ABSTRACT FROM AUTHOR]

It has been known since many years that there are histamine receptors (H) in the heart. Histamines display chronotropic and inotropic activity, cardiovascular diseases, and are thought to be a systemic inflammatory disease. During heart failure, the histamine concentration is elevated. In addition, H2 blockers prolonged the survival period for human patients with heart failure. The aim of this study was to evaluate whether blood concentration of histamine is associated with canine valvular disease (CVD). The histamine concentrations of dogs with CVD are significantly higher than those of healthy dogs. The histamine concentration gradually increases during CVD and is highly correlated with the grade of heart murmur. In conclusion, the histamine concentration was higher in the population of dogs with CVD compared with the healthy controls. Although the etiopathogenesis of CVD is complex and incompletely understood, it likely involves histamine. Ultimately additional studies are required to determine whether histamine blockers might be useful for the management of dogs with cardiac valvular disease. [ABSTRACT FROM AUTHOR]

Feline hyperthyroidism (HT) is a common endocrine disorder worldwide, but clinical and laboratory features might vary geographically. The aim of this retrospective study was to evaluate feline HT in Japan, and compare results to those of previous study for feline HT. We evaluated 48 feline HT cases clinical and laboratory features. Surprisingly, the youngest patient was 32 months of age (2 year 9 months). There was no significant difference among the study subjects in sex, but frequency of spayed/castrated cats was high (85.4%). Median age was 186 months (32-272 months). 91.3% (n=42) of subjects were over 10 years of age, and 8.7% (n=4) were under 10 years of age. Clinical symptoms included vomiting, 56.3% (n=27); diarrhea, 2.1% (n=1); hyperactivity, 12.5% (n=6); emaciation, 41.7% (n=20); polyuria and polydipsia, 22.9% (n=11); chronic weight loss, 60.4% (n=29); and palpated enlarged thyroid, 2.1% (n=1). Concurrent findings included chronic kidney disease, 20.8% (n=10); congestive heart failure, 20.8% (n=10); tachycardia (over 240 beats/min), 18.8% (n=9); gallop rhythm, 31.3% (n=15); neurological disorders such as hind-limb paralysis, 14.6% (n=7); cystitis, 8.7% (n=4); gingivitis, 4.2% (n=2); diabetes mellitus, 4.2% (n=2); and arterial thromboembolism, 6.3% (n=3). In addition, laboratory features (complete blood counts and biochemistry) differed from those of previous reports in certain respects. Our results show that it might be important for practitioners to comprehend epidemiologic differences regarding feline HT worldwide. [ABSTRACT FROM AUTHOR]