Thermal diffusivity anisotropy measured by a temperature wave method in the homologous series of (p-alkoxybenzylidene)-p'-octylaniline (nO.8).

The anisotropy of thermal diffusivity in four homologues of (p-alkoxybenzylidene)-p'-octylaniline (nO.8, n = 4 - 7) was measured using a temperature wave method. The results show that the thermal diffusivity component along the director (α(∥)) is considerably larger than that perpendicular to the director (α(⊥)) in all mesophases, i.e., nematic (N), smectic A (SmA), smectic B (SmB), and smectic G (SmG) phases. Both components of the thermal diffusivity show a dip at the second- or weakly first-order N-SmA phase transition due to the heat capacity anomaly. In contrast, at the first-order SmA-SmB phase transition, thermal diffusivity exhibits a stepwise increase. The x-ray and calorimetric measurements enable a calculation of the thermal conductivity and the study of the effect of the molecular length on the thermal conductivity and diffusivity in the SmA and SmB phases. For the homologues n = 4, 5, and 6, which exhibit the same phase sequence upon cooling, the parallel component of the thermal conductivity k(∥) in the SmA and SmB phases systematically increases with increasing length of the molecular tails, while no such increase is observed in the thermal diffusivity α(∥). We thus conclude that the molecular model [Urbach et al., J. Chem. Phys. 78, 5113 (1983)] is valid for the qualitative prediction of the effect of the molecular length on the magnitude of the thermal conductivity.

Discontinuous thermal diffusivity change due to the anchoring transition of a liquid crystal on a perfluoropolymer surface.

Thermal diffusivity of a liquid crystal, 4'-butyl-4-heptyl-bicyclohexyl-4-carbonitrile, was measured using a temperature wave method. The liquid crystal was sandwiched by two glass substrates, which were treated with three different surface agents for providing distinct molecular orientations. Here, we demonstrate that: 1) a large thermal diffusivity anisotropy arising from different orientations, that is, planar and homeotropic states, was found in the nematic and smectic A phases; 2) when substrates were coated with a perfluoropolymer, abrupt changes of the thermal diffusivity were observed in the nematic phase both on cooling and heating due to the discontinuous anchoring transition between planar and homeotropic states. The temperature dependence of the thermal diffusivity anisotropy was well described by a power law, with an exponent of 0.27 according to the mean-field theory.

[Primary renal malignant lymphoma in a hemodialysis patient : a case report].

A 71-year-old female on hemodialysis was referred to our hospital for a left renal mass which was incidentally found during a medical check-up. Abdominal computed tomography with intravenous contrast enhancement showed an iso-dense enhanced mass. Under the diagnosis of renal cell carcinoma, retroperitoneoscopic radical nephrectomy was performed. Histopathological examination revealed follicular lymphoma. This was the 20th case of primary renal lymphoma in Japan.

[An unusual case of cystic nephroma protruding into the renal pelvis].

Cystic nephroma is a relatively rare and benign renal lesion of uncertain etiology. Approximately 200 cases have been described, but only a few cases of cystic nephroma with prominent renal pelvis involvement have been reported. Here, we report an unusual case of cystic nephroma that protruded into the renal pelvis. A 45-year-old woman hospitalized because of a right renal mass detected on clinical examination. The diagnosis of a malignant or benign lesion was not clear. A right nephroureterectomy was performed. The characteristics of the resected specimen were consistent with those of cystic nephroma. Macroscopic examination revealed that the giant lesion originated from the upper renal pelvis and extended into the renal pelvis. The patient is currently free from disease at eight months after the surgery. In general, this tumor arises from the renal parenchyma. To our knowledge, this is the fifth case report on cystic nephroma with prominent renal pelvis involvement.

[A case of liposarcoma of spermatic cord with a hydrocele].

A 59-year-old man was referred to our hospital with the chief complaint of painless left scrotal swelling. He was diagnosed with left hydrocele testis and underwent puncture of hydrocele. Radical hydrocelectomy was performed because of its frequent recurrence in a short period. A hard mass was found across the spermatic cord during the operation. The mass was removed, and histopathological examination revealed a well-differentiated liposarcoma. This was the 107th case of liposarcoma of the spermatic cord and the 3rd case with a hydrocele.

[A case of retroperitoneal myxofibrosarcoma].

A 63-year-old man presented to our hospital suffering from dull pain in his right flank and general malaise.Abdominal computed tomography (CT) revealed a 21X14 cm retroperitoneal tumor adjacent to the right kidney. He underwent extirpation of the tumor,which weighed 2,900 g. Histopathological diagnosis was high-grade myxofibrosarcoma. Six months after initial surgery,CT revealed isolated metastasis in the upper lobe of the left lung,which was surgically treated. Eleven months after the original tumor excision, CT revealed lymph node metastasis dorsal to the inferior vena cava,which was also removed. Because he refused to receive adjuvant chemotherapy,he was observed for 2 months until CT revealed multiple liver metastases and para-aortic lymph node metastasis. He underwent 1 cycle of combined chemotherapy with doxorubicin and carboplatin,but metastatic lesions grew larger rapidly and his general state became too poor to continue chemotherapy. He is under best supportive care 17 months after the initial surgery.