Thermodynamic properties of a tetramer ferro-ferro-antiferro-antiferromagnetic Ising-Heisenberg bond alternating chain are investigated by the use of an exact mapping transformation technique. Exact results for the magnetization, susceptibility and specific heat in the zero as well as nonzero magnetic field are presented and discussed in detail. The results obtained from the mapping are compared with the relevant experimental data of Cu(3-Clpy)2(N3)2 (3-Clpy=3-Chloropyridine).

Abstract. Morphine, oxycodone, and fentanyl are clinically prescribed drugs for the management of severe pain. We investigated whether these opioids possess different efficacy profiles on several types of pain in mouse pain models. When the three opioids were tested in the femur bone cancer model, all of them significantly reversed guarding behavior, whereas the effects on limb-use abnormality and allodynia-like behavior differed among the opioids. Particularly, although oxycodone (5 -20 mg/kg) and fentanyl (0.2 mg/kg) significantly reversed limb-use abnormality, not even a high dose of morphine (50 mg/kg) could reverse it. When the effects of these opioids were examined in a sciatic nerve ligation (SNL) model of neuropathic pain, oxycodone was the most effective, producing an antinociceptive effect without affecting the withdrawal threshold of sham-treated animals. When the effects of these opioids were examined with the tail-flick test using naive animals, oxycodone, morphine, and fentanyl exhibited antinociceptive effects on thermal nociception. These results show that the three opioids exhibit different efficacy outcomes in multiple pain models and that the efficacy profile of oxycodone does not overlap those of morphine and fentanyl.

Ortho metalation by palladium(II) was observed in the reaction of lithium tetrachloropalladate(II) with various aromatic aldoximes and ketoximes in methanol in the presence of sodium acetate. The obtained chloro-bridged complexes(7) possessed both ortho-attached palladiumcarbon σ-bonding and palladium-nitrogen coordinate bonding to oximes. Reactions of O-acyl and O-methyl oximes with lithium tetrachloropalladate(II) were also carried out. An ortho metalation was observed in the former case, but dichlorobis(O-methyl oxime)palladium(II) type complexes containing no palladium-carbon σ-bonds were predominantly formed in the latter case. The bridge-splitting reaction of chloro-bridged complexes with triphenylphosphine and the metathetic reaction with sodium bromide in acetone were carried out. In the case of potassium tetrachloroplatinate(II), an ortho metalation reaction was observed giving the complexes(10) but chloro-bridged complexes could not be isolated.

We report the results of magnetic measurements on a powder sample of NiCu(pba)(D 2 O) 3 ·2D 2 O (pba=1,3-propylenebis(oxamato)) which is one of the prototypical examples of an S=1/2 and 1 ferrimagnetic chain. Susceptibility(χ) shows a monotonous increase with decreasing temperature (T) and reaches a maximum at about 7 K. In the plot of χT versus T , the experimental data exhibit a broad minimum and are fit to the χT curve calculated for the ferrimagnetic Heisenberg chain composed of S=1/2 and 1. From this fit, we have evaluated the nearest-neighbor exchange constant J/k B =121 K, the g-values of Ni 2+ and Cu 2+ , g Ni =2.22 and g Cu =2.09, respectively. Applied external field dependence of χT at low temperatures is reproduced fairly well by the calculation for the same ferrimagnetic model.Extensive studies of one-dimensional systems were prompted by Haldane's theoretical work [1] in 1983 after the initial wave of studies [2,3] In regard to the one-dimensional systems with magnetic ground states, an S=1/2 and 1 ferrimagnetic chain has been theoretically investigated recently, [6][7][8][9] in addition to some pioneering theoretical works [10,11] On the other hand, although some candidates for the ferrimagnetic Heisenberg chain composed of spin 1/2 and 1 exist in real bimetallic substances, [13,14] only preliminary magnetic measurements and comparisons with numerical calculations were made.[13] Thus, we investigate precisely the magnetic properties of an alternating Ni and Cu chain compoundIn these measurements, we use a deutrated sample because it is of superior quality to a hydrated one, although reason for this remain unclear and we plan to perform neutron scattering measurements on this deutrated sample. The format used in this letter is as follows: in the next section, we discuss the synthesis and crystal structure of NiCu (pba) Magnetic measurements were carried out with a SQUID magnetometer (Quantum Design's MPMS-XL7L) at KYOKUGEN in Osaka University. We show in Fig. 2 the dc magnetic susceptibility χ(=M/H where M and H represent magnetization of the sample and the external magnetic field, respectively) of a powder sample of NiCu(pba)(The susceptibility of NiCu(pba)(D 2 O) 3 ·2D 2 O increases monotonously with decreasing temperature until about 7 K, at which the susceptibility reaches a maximum. Below 7 K, the long-range order probably occurs due to the interchain couplings. Figure 3 shows χ times T of NiCu(pba)(D 2 O) 3 ·2D 2 O as a function of temperature. This plot is familiar to chemists but not to physicists. Therefore, we explain this plot in some details. If a magnetic system is paramagnetic, χT is constant over the whole temperature range. If a magnetic system has a dominant ferromagnetic (antiferromagnetic) interaction, χT increases (decreases) when the temperature is decreased. In Fig. 3, χT decreases when 3 decreasing the temperature from 300 K, implying that antiferromagnetic coupling exists between the nearest neighbor spins, and reaches a rounded minimum at about 70 K. Then, χT increa...

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BACKGROUND AND PURPOSEBone cancer pain is chronic and often difficult to control with opioids. However, recent studies have shown that several opioids have distinct analgesic profiles in chronic pain. EXPERIMENTAL APPROACHTo clarify the mechanisms underlying these distinct analgesic profiles, functional changes in the m-opioid receptor were examined using a mouse femur bone cancer (FBC) model. KEY RESULTSIn the FBC model, the Bmax of [ CONCLUSION AND IMPLICATIONSThese results show that m-opioid receptor functions are attenuated in several pain-related regions in bone cancer in an agonist-dependent manner, and suggest that modification of the m-opioid receptor is responsible for the distinct analgesic effect of oxycodone and morphine.