Understanding the Factors that Influence Perceptions of Post-Wildfire Landscape Recovery Across 25 Wildfires in the Northwestern United States.

Disturbances such as wildfire are important features of forested landscapes. The trajectory of changes following wildfires (often referred to as landscape recovery) continues to be an important research topic among ecologists and wildfire scientists. However, the landscape recovery process also has important social dimensions that may or may not correspond to ecological or biophysical perspectives. Perceptions of landscape recovery may affect people's attitudes and behaviors related to forest and wildfire management. We explored the variables that influence people's perceptions of landscape recovery across 25 fires that occurred in 2011 or 2012 in the United States of Washington, Oregon, Idaho, and Montana and that represented a range of fire behavior characteristics and landscape impacts. Residents near each of the 25 fires were randomly selected to receive questionnaires about their experiences with the nearby fire, including perceived impacts and how the landscape had recovered since the fire. People generally perceived landscapes as recovering, even though only one to two years had passed. Regression analysis suggested that perceptions of landscape recovery were positively related to stronger beliefs about the ecological role of fire and negatively related to loss of landscape attachment, concern about erosion, increasing distance from the fire perimeter, and longer lasting fires. Hierarchical linear modeling (HLM) analysis indicated that the above relationships were largely consistent across fires. These findings highlight that perceptions of post-fire landscape recovery are influenced by more than vegetation changes and include emotional and cognitive factors. We discuss the management implications of these findings.

Isosteric and non-isosteric modification of carboxyl groups of papain.

Guanidinated mercuri-papain (Gu-papain) was reacted with N-ethylbenzisoxazolium tetrafluoroborate at pH 4.2, 0 degree C, to yield highly reactive N-ethylsalicylamide esters. On varying the amount of reagent applied 2.5-10 carboxyl groups were modified. Appropriate plotting of the data indicated that all 12 groups exposed in the X-ray structure were modified to an extent of 80% in the final preparation, concomitant with a similar loss of activity towards N alpha-benzoyl-L-arginine ethyl ester. The preparations regained complete activity on saponification of the ester groups and removal of some oligomeric material by gel filtration. Considerable activity was recovered when the ester groups were completely replaced by amide groups by subjecting the esters to ammonolysis in 2 M ammonium acetate/ammonia (pH 9.2). The final preparation, after gel filtration, exhibited Km = 57 +/- 1 mM and kcat = 26 +/- 0.2 s-1 towards BAEE (native papain Km = 18 mM and kcat = 26 s-1). It may be concluded that replacement of a bulky modifying group by an isosteric one may cause considerable recovery of activity, emphasizing the importance of isostericity in suppressing the ionizing ability of ionizable groups; furthermore, that a large shift in overall charge, caused by amidation of all accessible carboxyl groups, does not affect the catalytic steps. The absence of effect of side-chain charges on the ion pair in the active site is briefly discussed.

Motor dominance and lateral asymmetry of the globus pallidus.

Animal experiments suggest that neurochemical and anatomic asymmetries exist within the basal ganglia, particularly the globus pallidus, and that these asymmetries correlate with both preferred direction of rotation and limb preference in lever pressing. Human neurotransmitter studies have also revealed a significant asymmetry within the globus pallidus, the left containing greater amounts of dopamine and choline acetyltransferase than the right. Recent anatomic studies of human subcortical regions, limited to the striatum, have failed to show a size asymmetry. We examined 18 normal brains in subjects ranging in age from 26 weeks gestation to 86 years for volumetric asymmetry of the globus pallidus. We found a significant asymmetry, the left side measuring larger in 16 of 18 brains. Considering the role of the basal ganglia in motor control, this data may reflect a structural basis of either axial or limb motor dominance in humans.

Hemispatial visual inattention masquerading as hemianopia.

The defect occurring when a patient fails to report a visual stimulus presented in a visual half-field may be attributed to hemianopia (deafferentation) caused by a geniculocalcarine lesion. However, failure to report a stimulus presented in a visual field may also be caused by hemispatial visual inattention. We report a patient with right thalamic and temporo-occipital lesions who had a left visual field defect when her eyes were directed either straight ahead (midsagittal plane) or toward left hemispace. However, this visual field defect abated when her eyes were directed to right hemispace, suggesting that the patient had hemispatial visual inattention rather than hemianopia.

Hemispatial neglect affected by non-neglected stimuli.

Patients with hemispatial neglect fail to cancel lines distributed on one side of a piece of paper. This defect is thought to be induced by a deficit in the neuronal systems that mediate attention, intention, and exploration toward and in the hemispace contralateral to the lesion. However, an alternate (but not mutually exclusive) interpretation is that the patients are either strongly attracted to or impaired in disengaging from the stimuli occupying the other, non-neglected hemispace. We tested ten patients with neglect on two versions of a cancellation test. In the control test they cancelled lines by drawing over them, and in the experimental test they erased lines. There were significantly more omissions in the drawing-over task than in the erasing task. The improved performance when lines were cancelled by removal instead of by marking them suggests that hemispatial neglect is influenced by the presence of stimuli in the non-neglected hemispace.

Isolated lexical agraphia in a right-handed patient with a posterior lesion of the right cerebral hemisphere.

Lexical agraphia is thought to result from impairment of the lexical spelling system and is characterized by better spelling of nonwords and regularly spelled words than irregularly spelled words. Previous reports have suggested a localization of this syndrome in the region of the left posterior-superior angular gyrus and parietal-occipital lobule, sparing the supramarginal gyrus. We describe a right-handed man who after open-heart surgery displayed lexical agraphia without aphasia, alexia, apraxia, or Gerstmann's syndrome. Computed tomography disclosed a lesion not on the left but on the right in the posterior parietal-occipital region.

Neuropathologic findings in idiopathic opsoclonus and myoclonus. Their similarity to those in paraneoplastic cerebellar cortical degeneration.

The neuropathologic findings in an idiopathic case of the opsoclonus/myoclonus syndrome are reported. Although neurologic dysfunction may have been more widespread, structural lesions were limited to the cerebellum and inferior olives. Severe depletion of Purkinje cells with preservation of granular cells was evident throughout the neo- and paleocerebellum; however, groups of Purkinje cells were preserved in the archicerebellum. No abnormalities were evident in the paramedian pontine reticular formation of the caudal pons. Inflammation and evidence of anoxic damage were absent. These changes are very similar to those described in paraneoplastic cerebellar cortical degeneration.

Isosteric conversion of protein carboxyl groups into carboxamide groups. II. Application to lysozyme.

For isosteric conversion of carboxyl groups of proteins into amide groups, ammonolysis of protein esters under mild conditions was attempted. Ammonolysis of methyl esters of lysozyme and bovine serum albumin proved to be incomplete. Highly reactive N-ethylsalicylamide esters of guanylated lysozyme were therefore prepared by subjecting the protein to reaction with N-ethylbenzisoxazolium ion at pH 4.2, 0 degree. Per molecule, 5-7 ester groups were introduced, with concomitant decrease of activity of 80-90%. Only 0.3 tyrosine was modified. On hydrolysis at pH 9.2 the activity was completely restored. At pH 7.9 three classes of ester groups could be distinguished: one group of high rate of hydrolysis (k1 = 1.5 min-1), three groups of intermediate rate (k2 = 0.13 min-1) and two groups of low rate (k3 = 0.018 min-1). The intermediate rate approximated the rate of hydrolysis of the model compound benzoylglycine N-ethylsalicylamide ester (k = 0.15 min-1). Ammonolysis at pH 9.2 in 2.0 M ammonia/ammonium acetate provided complete conversion of the ester groups into amide groups without restoration of activity, confirming the essentiality of certain carboxyl groups. In particular, rearrangement of the ester groups into relatively stable imide groups by O-N acyl migration was found to be completely absent. When native lysozyme was esterified with N-ethylbenzisoxazolium ion the activity did not completely return on hydrolysis.

Memory loss from a subcortical white matter infarct.

Clinical disorders of memory are believed to occur from the dysfunction of either the mesial temporal lobe, the mesial thalamus, or the basal forebrain. Fibre tract damage at the level of the fornix has only inconsistently produced amnesia. A patient is reported who suffered a cerebrovascular accident involving the posterior limb of the left internal capsule that resulted in a persistent and severe disorder of verbal memory. The inferior extent of the lesion effectively disconnected the mesial thalamus from the amygdala and the frontal cortex by disrupting the ventral amygdalofugal and thalamic-frontal pathways as they course through the diencephalon. This case demonstrates that an isolated lesion may cause memory loss without involvement of traditional structures associated with memory and may explain memory disturbances in other white matter disease such as multiple sclerosis and lacunar state.