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Abstract: The combination of palynofacial and sedimentological analyses constitutes a valuable method for paleoenvironmental and paleoclimatic reconstructions, especially when fossil pollen information is scarce or absent. This methodology elucidates a late Pleistocene/Holocene sequence at the Paso Otero 5 archaeological site in the middle basin of the Quequén Grande River, Necochea district, Buenos Aires province, Argentina. Although the main factor responsible for the destruction of pollen grains is pH, biochemical and chemical oxidation and mechanical damage contribute to the deterioration as well. The site sequence indicates that extremely arid climatic conditions without vegetation cover prevailed during the late Pleistocene (∼12,000 14C yr BP), after which the climate changed to semiarid conditions associated with a disturbed environment due to strong eolian activity (Palynofacies 1 and 2; pre-10,400 14C yr BP). During the Pleistocene/Holocene transition (Palynofacies 3 and 4; ∼10,400–9400 14C yr BP), loamy facies associated with paleosoils reflected stable conditions and temporary ponds (spring deposits). Similar conditions occurred near the end of early Holocene (Palynofacies 5–9; ∼9400–6600 14C yr BP), whereas sandy and silty facies are associated with the flood margins of streams or rivers in the middle and late Holocene (Palynofacies 10–14; 6600–2500 14C yr BP). The top of the sequence (Palynofacies 15 and 16) consists of alluvium sediments and reflects locally humid conditions and modern vegetation with anthropic influence. One of the earliest Pampean sites with evidence of humans (10,450–10,200 14C yr BP), Paso Otero 5, provides a variety of megafauna bone specimens associated with ``fish-tail” projectile points, a lithic artifact diagnostic of early human occupations in South America. The site contains a complete stratigraphic record from the late Pleistocene to the present. The evidence presented herein supports the hypothesis that human colonization, at least in some areas of the southern cone, took place within severe, fluctuating climatic conditions. [Copyright &y& Elsevier]

Both anxiety and depression are associated with lower self-perceived health status (HS) in persons with Parkinson's disease (PD). Given the high co-morbidity with depression and other non-motor symptoms, it is unclear whether anxiety disorders, in general, versus specific anxiety subtypes have an independent effect on HS in PD. To examine this question, comprehensive assessments of motor and non-motor symptoms from 249 subjects with idiopathic PD followed in three community-based movement disorders neurology practices were analyzed. HS was measured using the 8-item PD Questionnaire (PDQ-8). Psychiatric diagnoses were established by consensus using a panel of six psychiatrists with expertise in geriatric psychiatry and movement disorders. Stepwise multiple regression analyses were used, with the PDQ-8 score as the dependent variable, to identify independent predictors of HS among motor, psychiatric, and other non-motor variables. Among the anxiety disorders, only anxiety associated with motor fluctuations was an independent predictor of HS after accounting for co-morbid depression and other clinical features. In addition, depressive disorders were also an independent predictor of lower HS. Prevention or treatment of state-dependent anxiety may improve HS in persons with PD. [ABSTRACT FROM AUTHOR]