Bulk Superconductivity up to 122 K in the Tl-Pb-Sr-Ca-Cu-O System

New high-temperature superconductors based on oxides of thallium and copper, but not containing barium, have been prepared. A transition temperature (T(c)) of about 85 K is found for (Tl(0.5)Pb(0.5)) Sr(2)CaCu(2)O(7) whereas (Tl(0.5)Pb(0.5))Sr(2)Ca(2)Cu(3)O(9) has a T(c) of about 120 K. Both materials possess tetragonal symmetry with a = 3.80 A, c = 12.05 A for (Tl(0.5)Pb(0.5))Sr(2)CaCu(2)O(7), and a = 3.81 A, c = 15.23 A for (Tl(0.5)Pb(0.5))Sr(2)Ca(2)Cu(3)O(9). A structure refinement of the latter phase has been carried out with single-crystal x-ray diffraction data.     

Evolution of magnetic and superconducting fluctuations with doping of high-Tc superconductors

Electronic Raman scattering from high- and low-energy excitations was studied as a function of temperature, extent of hole doping, and energy of the incident photons in Bi2Sr2CaCu2O8+/-delta superconductors. For underdoped superconductors, short-range antiferromagnetic (AF) correlations were found to persist with hole doping, and doped single holes were found to be incoherent in the AF environment. Above the superconducting (SC) transition temperature Tc, the system exhibited a sharp Raman resonance of B1g symmetry and energy of 75 millielectron-volts and a pseudogap for electron-hole excitations below 75 millielectron-volts, a manifestation of a partially coherent state forming from doped incoherent quasi particles. The occupancy of the coherent state increases with cooling until phase ordering at Tc produces a global SC state.     

Tenoscopy in 33 horses with septic and nonseptic digital tenosynovitis (1997–2001)

Tenoscopy is the use of an arthroscope to access tendon sheaths. This article reports clinical findings, treatments, and outcomes of 33 horses with either septic or nonseptic digital tenosynovitis submitted to 36 tenoscopies during 34 occasions at the Marion duPont Scott Equine Medical Center (1997–2001). Two of the 16 horses with septic tenosynovitis were euthanized at the hospital. From the 32 horses discharged from the hospital, outcome was obtained in 31 cases: 12 horses (6 septic) could work at the same level. No difference was detected between the outcome groups regarding clinical and laboratory variables. In nonseptic cases, lameness grade, circulating white blood cells, and plasma fibrinogen before surgery were lower, while the period between the onset of clinical signs and surgery was longer and duration of phenylbutazone treatment and hospitalization was shorter. No difference in the outcome was detected when septic and nonseptic cases were compared. Tenoscopy was useful for diagnosis and treatment of nonseptic and septic digital tenosynovitis. The small number of cases and the lack of accurate information due to the retrospective nature of the study may have prevented detection of a difference between the outcomes of horses with septic versus nonseptic tenosynovitis.     

Disease incidence in Eucalyptus microtheca provenances

A provenance trial of Eucalyptus microtheca F. Muell. was studied in order to select resistant provenances against Cytospara eucalypti twig blight, Pestalotiopsis versicolor stem canker and Botryodiplodia theobromae root collar canker. Out of 21 provenances tried, 4 provenances were screened as resistant against diseases and showed best performance.     

Spontaneous chondrosarcoma in Wistar rat: a case report

In rats, chondrosarcomas have been reported to occur both spontaneously and secondary to chemical induction. In a rare case, a spontaneous chondrosarcoma was identified in the deformed femur of a young male Wistar rat. After gross examination of the femur and knee joint, tissue was collected and preserved. The formalin-fixed tissue was decalcified, embedded in paraffin, sectioned, and stained with hematoxylin and eosin. Microscopic examinations revealed a large, highly proliferative, noncapsulated growth of chondrocytic or chondroblastic origin in the femoral bone, with proliferating chondrocytes invading the bone and surrounding tissues in an infiltrative growth pattern. Based on its histomorphological features, the lesion was diagnosed as a malignant cartilaginous neoplasm of spontaneous origin.     

Arsenic Removal from Drinking Water using Iron Oxide-Coated Sand

This article describes experiments in which iron oxide-coated sand(IOCS) was used to study the removal of both As(V) and As(III) to a level less than 5 μg L^-1 in drinking water. Iron oxide-coated sand 2 (IOCS-2) prepared through high temperature coating process was used in batch and column studies to assess the effectiveness and suitability. The isotherm study results showed that the observed data fitted well with the Langmuir model, and the adsorption maximum for IOCS-2 at pH 7.6 was estimated to be 42.6 and 41.1 μg As g^-1 IOCS-2 for As(V) and As(III), respectively. In the fixed bed column tests to study arsenic removal from the tap water, good performance ofIOCS-2 was observed in respect of bed volumes achieved and arsenic removal capacity. Five cycles of column tests were conducted to evaluate the performance of IOCS-2, and arsenic wassuccessfully recovered from the media through regeneration and backwash operations. High bed volumes (860 to 1403) up to a breakthrough concentration of 5 μg L^-1 were achieved inthe column studies with tap water, and the bed volumes achievedin the studies with natural water (containing arsenic) were 1520.The results of both the batch and column studies showed that ironoxide-coated sand filtration could be effectively used to achieveless than 5 μg L^-1 As in drinking water.     

Proteome-level investigation of Brassica carinata-derived resistance to Leptosphaeria maculans

Plants resistant to the fungal pathogen Leptosphaeria maculans were generated by an interspecific cross between the highly susceptible Brassica napus (canola) and the highly resistant Brassica carinata. Changes in the leaf protein profiles of these lines were investigated in order to understand the biochemical basis for the observed resistance. Two-dimensional electrophoresis followed by tandem mass spectrometry led to the identification of proteins unique to the susceptible (5 proteins) and resistant genotypes (7 proteins) as well those that were differentially expressed in the resistant genotype 48 h after challenge with the pathogen (28 proteins). Proteins identified as being unique in the resistant plant material included superoxide dismutase, nitrate reductase, and carbonic anhydrase. Photosynthetic enzymes (fructose bisphosphate aldolase, triose phosphate isomerase, sedoheptulose bisphosphatase), dehydroascorbate reductase, peroxiredoxin, malate dehydrogenase, glutamine synthetase, N-glyceraldehyde-2-phosphotransferase, and peptidyl-prolyl cis-trans isomerase were observed to be elevated in the resistant genotype upon pathogen challenge. Increased levels of the antioxidant enzyme superoxide dismutase were further validated and supported by spectrophotometric and in-gel activity assays. Other proteins identified in this study such as nitrate reductase and peptidylprolyl isomerase have not been previously described in this plant-pathogen system, and their potential involvement in an incompatible interaction is discussed.