Chemical Weathering in a Tropical Watershed, Luquillo Mountains, Puerto Rico: I. Long-Term Versus Short-Term Weathering Fluxes

Short-term climatic events produce some of the most dramatic ecosystem responses. Sometimes the responses may last for a long time into the future. Three themes will be emphasized in this synthesis. The first is that shortterm climatic events have both short- and long-term responses in the ecosystem. Second, the timing of short-term events is important in partially determining the kind and degree of ecosystem response that might occur. A third theme is the importance of putting short-term variability into a long-term context. The chapters about hurricanes and droughts in this section demonstrate that shortterm climatic events may have short- and long-term responses in the ecosystem. Both the short- and long-term responses are important. The short-term responses have noteworthy economic influences in the agricultural ecosystem. One could argue that the ecosystems containing species with short life spans such as grasslands are able to respond and recover from a short-term climatic disturbance more quickly than those ecosystems with longer lived species such as trees. Corn responds quickly to variability in precipitation during important parts of the growing season. Gage believes the long-term effects of a short-term drought on annual rotational agronomic systems are generally minimal. Other LTER studies have documented strong relationships between annual precipitation and grassland aboveground net primary productivity (Knapp et al. 1998). Conversely, the Coweeta study brings to our attention the insidious, long-term effects of drought that quietly kills trees and leaves their dead necromass on the landscape for decades into the future. However, each ecosystem is responding at its own characteristic timescale. Boose notes that the mixed hardwood forests of central New England and the Tabonuco forests of Puerto Rico both exhibit remarkable resiliency to wind damage. In both cases, despite major structural reorganization after a hurricane, there was rapid regeneration of canopy cover through releafing, sprouting, or recruitment, which helped to reduce impacts on soil moisture, temperature, and nutrient cycling processes. Nevertheless, some signs of the hurricane impact are present for decades, although less so in Puerto Rico where decomposition and regeneration rates are much faster than in New England.

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Archaeology of marronage in the Caribbean Antilles

Revista do Museu de Arqueologia e Etnologia ◽

10.11606/issn.2448-1750.revmae.2020.164882 ◽

2020 ◽

pp. 1-13

Author(s):

Theresa Ann Singleton

Keyword(s):

Puerto Rico ◽

Greater Antilles ◽

Small Islands ◽

Short Term ◽

Caribbean Islands ◽

The Caribbean ◽

Preliminary Research ◽

Local Term

The archaeological study of maroons in the Caribbean Antilles presents both opportunities and challenges. On small islands, runaways had few places where they could seek refuge from slavery and elude capture for long periods of time. Consequently, such sites were occupied briefly and have been difficult to locate and identify. The Greater Antilles (Cuba, Jamaica, Hispaniola, and Puerto Rico) had both short-term refuge sites and long-term settlements comparable to quilombos. Archaeologists have been most successful in their investigations maroons in Cuba and Jamaica. In Hispaniola, where I am working at the present, only a few cave sites and one presumed maniel (the local term for a long-term maroon settlements) have been studied. In this paper, I provide an overview of the archaeological study of maroons on the Caribbean Islands and my preliminary research to locate El Maniel de Ocoa, a major settlement of slave runaways for over a hundred years during 1500s-1660s.

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Long-term patterns and short-term dynamics of stream solutes and suspended sediment in a rapidly weathering tropical watershed

Water Resources Research ◽

10.1029/2010wr009788 ◽

2011 ◽

Vol 47 (7) ◽

Cited By ~ 40

Author(s):

James B. Shanley ◽

William H. McDowell ◽

Robert F. Stallard

Keyword(s):

Suspended Sediment ◽

Short Term ◽

Tropical Watershed

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Stable-isotope and solute-chemistry approaches to flow characterization in a forested tropical watershed, Luquillo Mountains, Puerto Rico

Applied Geochemistry ◽

10.1016/j.apgeochem.2015.03.008 ◽

2015 ◽

Vol 63 ◽

pp. 484-497 ◽

Cited By ~ 12

Author(s):

Martha A. Scholl ◽

James B. Shanley ◽

Sheila F. Murphy ◽

Jane K. Willenbring ◽

Marcie Occhi ◽

...

Keyword(s):

Puerto Rico ◽

Stable Isotope ◽

Flow Characterization ◽

Luquillo Mountains ◽

Solute Chemistry ◽

Tropical Watershed

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Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

Behavioral and Brain Sciences ◽

10.1017/s0140525x15000928 ◽

2016 ◽

Vol 39 ◽

Author(s):

Mary C. Potter

Keyword(s):

Working Memory ◽

Rapid Serial Visual Presentation ◽

Language Comprehension ◽

Short Term Memory ◽

Visual Presentation ◽

Long Term Memory ◽

Short Term ◽

Term Memory ◽

Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

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Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159412 ◽

1990 ◽

Vol 48 (3) ◽

pp. 374-375

Author(s):

D.E. Loudy ◽

J. Sprinkle-Cavallo ◽

J.T. Yarrington ◽

F.Y. Thompson ◽

J.P. Gibson

Keyword(s):

Antidepressant Drug ◽

Beagle Dogs ◽

Long Term Effects ◽

Short Term ◽

Platelet Counts ◽

Toxicological Studies ◽

Induced Aggregation ◽

Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

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Comparison of Auditory, Language, Memory, and Attention Abilities in Children With and Without Listening Difficulties

American Journal of Audiology ◽

10.1044/2020_aja-20-00018 ◽

2020 ◽

Vol 29 (4) ◽

pp. 710-727

Author(s):

Beula M. Magimairaj ◽

Naveen K. Nagaraj ◽

Alexander V. Sergeev ◽

Natalie J. Benafield

Keyword(s):

Auditory Processing ◽

Short Term Memory ◽

Group Differences ◽

Long Term Memory ◽

Short Term ◽

Significant Group ◽

Term Memory ◽

Memory And Attention ◽

Speed And Accuracy

Objectives School-age children with and without parent-reported listening difficulties (LiD) were compared on auditory processing, language, memory, and attention abilities. The objective was to extend what is known so far in the literature about children with LiD by using multiple measures and selective novel measures across the above areas. Design Twenty-six children who were reported by their parents as having LiD and 26 age-matched typically developing children completed clinical tests of auditory processing and multiple measures of language, attention, and memory. All children had normal-range pure-tone hearing thresholds bilaterally. Group differences were examined. Results In addition to significantly poorer speech-perception-in-noise scores, children with LiD had reduced speed and accuracy of word retrieval from long-term memory, poorer short-term memory, sentence recall, and inferencing ability. Statistically significant group differences were of moderate effect size; however, standard test scores of children with LiD were not clinically poor. No statistically significant group differences were observed in attention, working memory capacity, vocabulary, and nonverbal IQ. Conclusions Mild signal-to-noise ratio loss, as reflected by the group mean of children with LiD, supported the children's functional listening problems. In addition, children's relative weakness in select areas of language performance, short-term memory, and long-term memory lexical retrieval speed and accuracy added to previous research on evidence-based areas that need to be evaluated in children with LiD who almost always have heterogenous profiles. Importantly, the functional difficulties faced by children with LiD in relation to their test results indicated, to some extent, that commonly used assessments may not be adequately capturing the children's listening challenges. Supplemental Material https://doi.org/10.23641/asha.12808607

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