Rotational position of curved saw logs and warp of the sawn timber

With the development of scanning technology in sawmills, it is possible to optimise log rotational position when sawing. However, choosing a different rotational position than horns down might be detrimental for the board shape after drying, especially for curved logs. Thus, there is a need to investigate at what level of log curve it is possible to freely rotate logs without causing board warp. This study was carried out through a test sawing that was conducted at a sawmill situated in the middle of Sweden. The tests were made on 177 Norway spruce logs, with varying amount of curve. Half of the logs were sawn in the horns-down position, half were sawn rotated perpendicular to horns down. Log shape and warp of the dried boards were measured. The results indicated a relationship between board spring, log curve and choice of rotational position. Furthermore, board bow was related to log curve but not rotational position. It can be concluded that for straight logs, with a bow height of less than 15 mm, an unconventional rotational position does not cause excess spring in the boards. Bow and twist are not affected by the rotational position at all.     

Beliefs about urban fringe forests among urban residents in Sweden

The aim of this study was to examine predictors of beliefs about urban fringe forests among urban residents in Sweden (n = 586). Based on a cognitive hierarchical model, the study investigated how socio-demographic variables, as well as different values and beliefs, were related to the more specific beliefs urban residents have about urban fringe forests. Results demonstrated that the urban fringe forest was perceived to be essential for personal wellbeing, but preservation and accessibility to the forest were also important. Certain differences between socio-demographic groups were identified; for example, the importance of urban fringe forests for personal wellbeing was emphasized more by women, older people and those with a university degree. However, the importance of socio-demographic variables was modest compared with the influence of people's values and beliefs. More specifically, results showed that urban residents’ basic values and ecological worldview, as well as forest values and beliefs (i.e., concerning forest qualities and forest requirements), were important in explaining their beliefs about urban fringe forests. Overall, the study revealed that urban residents are characterized by a heterogeneous set of beliefs concerning urban fringe forests. Recognizing these multiple beliefs in urban fringe forest development processes may help mitigate future conflicts between forest visitors, urban planners, forest owners and forest managers, thus enhancing our way toward good urban living environments.     

Heifer mastitis and dry-cow mastitis: A bacteriological survey in Sweden

A bacteriological investigation was performed on 145 heifers and 55 dry-cows with clinical mastitis during July 1976–June 1977. Areas in Sweden from which heifer and dry-cow mastitis has been reported as a problem were included. Mastitis occurred more frequently in the Swedish Fresian breed (SLB) than in the Swedish Red and White breed (SRB) of dairy cattle. C. pyogenes was isolated in pure culture from 15% and 4%, respectively, of the cases of heifer and dry-cow mastitis from which this bacterium could be isolated. Corresponding figures for pure culture of P. indolicus, micro-aerophilic cocci and S. dysgalactiae were 2% and 0%, 0% and 0% and 44% and 35%, respectively. The bacteria most frequently isolated together with C. pyogenes in the heifer material were P. indolicus (69%), the microaerophilic cocci (59%) and S. dysgalactiae (31%). Corresponding data for the dry-cow material were 92%, 35% and 50%, respectively. Thus, C. pyogenes was the causative agent of heifer and dry-cow mastitis in only about 40% of the mastitis cases investigated, and the most characteristic feature of these forms of mastitis involving C. pyogenes was mixed infection.     

Galacturonic acid groups in birch xylan

Summary A large number of reducing xylose end groups are present in birch wood (Betula verrucosa) while all galacturonic acid moieties are non-reducing. A large portion of the reducing xylose end groups are removed during treatments with alkali used for the islation of xylan, while reducing galacturonic acid moieties are formed by endwise degradation during this procedure.The financial support from the 1959 Års Fond för Teknisk och Skoglig Forskning samt Utbildning is gratefully acknowledged.     

Toxicologic evaluation of chlorpyrifos in cats

Twenty-four male domestic shorthair cats were used to evaluate the acute and chronic effects of a single, toxic but sublethal, orally administered dose of chlorpyrifos. A dosage of 10 mg/kg of body weight did not induce clinical signs of toxicosis, but a dosage of 40 mg/kg induced clinical signs of toxicosis, and 1 of 12 cats died. Chlorpyrifos given at a dosage of 0.1 mg/kg to 2 cats reduced whole blood and plasma cholinesterase (Che) activities to values obtained after cats were given doses that induced clinical signs of toxicosis. Regeneration time for whole blood and plasma Che activities ranged from 7 to 28 days. Brain Che activity was considerably decreased in 1 cat that died 4.5 hours after dosing, but was normal in all others at 28 days after dosing. Other than decreased Che activity, significant changes were not seen in hematologic or serum biochemical values. Toxin-related lesions were not seen during macroscopic or microscopic examination.     

Enzymatic-spectrophotometric method for determination of cholinesterase activity in whole blood: collaborative study

Ten collaborating laboratories assayed 4 blind duplicate pairs of whole bovine blood for cholinesterase activity. The 4 sample pairs ranged from normal (100%) to severely organo-phosphorus-inhibited (less than 10%) activity. Collaborators also received commercially available human lyophillized serum as an external control and a chromate solution to evaluate spectrophotometer performance. The Ellman kinetic assay was performed on a 1:1000 dilution of the whole blood in pH 8.0 phosphate buffer. The method monitors the increase in absorbance at 412 nm caused by formation of 5-thio-2-nitrobenzoic acid (yellow reaction product). Repeatability standard deviations (RSDr) ranged from 4.30 to 14.2%; reproducibility standard deviations (RSDR) ranged from 6.99 to 19.3%. The lower limit of detection was estimated to be 0.10 mumole/mL/min. The method has been approved interim official first action by AOAC.     

Short feeding migration associated with a lower mean size of whitefish in the River Tornionjoki,northern Baltic Sea

The size of anadromous whitefish caught with dip nets in the River Tornionjoki in the northern part of the Gulf of Bothnia has decreased during recent decades. To find an explanation for this trend, ascending whitefish were sampled in the lower part of the river in August 2016, and they were divided into two groups according to fish length. The length of the SMALL group was ≤ 32 cm (n = 32) and that of the LARGE group ≥ 33 cm (n = 65). The elemental analysis of otoliths revealed that the barium concentration was clearly higher in otoliths from the SMALL group compared to the LARGE group. This indicates that the fish in the LARGE group had migrated to feed further south in the Gulf of Bothnia, with a higher salinity, than the fish in the SMALL group. Because of this migration difference, and a decline in the gillnet effort, especially in the feeding areas near the river mouth, it is assumed that proportionally more fish in the SMALL group are able to ascend the river to spawn than previously, thus decreasing the mean size. At the same time, the heavy gillnet fishery in the south removes fish from the LARGE group.     

Thymocyte growth factor: A progression growth factor for cycling immature cortical thymocytes

A growth factor for cultured guinea pig thymocytes was isolated from an extract of calf thymus. This thymocyte growth factor (TGF) was purified to apparent homogeneity employing reverse phase high performance liquid chromatography as the final step. TGF was characterized as an N-terminal blocked hydrophilic peptide with an apparent M_r of 1600. The amino acid composition revealed a high content of acidic amino acids but no apparent relationship with previously defined growth factors and thymic differentiation hormones. TGF was active in nanomolar concentration and stimulated the DNA synthesis and mitotic activity specifically in a subpopulation of thymocytes with immature cortical phenotype. The responsive thymocytes were recruited from G₁ into S phase within 2 h after addition of TGF. In the absence of the growth factor, the target cells were blocked at a putative restriction point in G₁, prior to the onset of the S phase. It is proposed that TGF is a progression growth factor participating in the regulation of the intense proliferation of immature thymocytes in the thymus cortex in vivo.     

Antigenic analysis of Peptococcus indolicus by crossed immunoelectrophoresis

Quantitative immunoelectrophoretic methods have been used to study the antigenic mosaic of Peptococcus indolicus, an anaerobic coccus frequently isolated from udder secretions from heifers and dry cows with mastitis. Three antigenic components of liquid cultures of this bacterium were analyzed, compared and characterized, namely concentrated culture filtrate containing extracellular antigens, a cytoplasmic antigen fraction obtained by freeze-press disruption of bacterial cells and Triton X-100-soluble antigens from cell wall-membrane fractions. The extracellular antigens were further investigated because they proved to be particularly useful in preliminary studies on the antibody response of cows to P. indolicus. The possible cross-reactivity of peptococcal antigens with extracellular antigens from other bacteria causing, or associated with, mastitis was investigated. The contribution of medium components to the immunoprecipitate profile, the heat-stability of antigens and the relationship of serotypic antigens to those in the standard extracellular concentrate were established using co-immunoelectrophoresis, crossed-line immuno-electrophoresis and crossed immunoelectrophoresis with intermediate gel. Attempts to identify enzyme-active immunoprecipitates with histochemical enzyme staining methods revealed only glutamate dehydrogenase.