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1.
Sci Total Environ ; 927: 172053, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38556010

ABSTRACT

Tropical environments show great potential to sequester CO2 by enhanced rock weathering (ERW) of powdered mafic rocks applied to agricultural fields. This study seeks to assess carbon dioxide reduction (CDR) potential in the humid tropics (1) by experimental weathering of mafic rock powders in conditions simulating humid tropical soils, and (2) from weathering rates determined from a Holocene tropical soil chronosequence where parent material is andesitic sediments. Experimentally determined weathering rates by leaching of basaltic andesites from Costa Rica (Arenal and Barva) for 50 t ha-1 applications indicate potential sequestration of 2.4 to 4.5 t CO2 ha-1 yr-1, whereas the USGS basalt standard BHVO-1 yields a rate of 11.9 t ha-1 yr-1 (influenced by more mafic composition and finer particle size). The chronosequence indicates a rate of 1.7 t CO2 ha-1 yr-1. The weathering experiment consisted of 0.6 mm of powdered rock applied atop 12 mm of Ultisol at 35 °C. To simulate a tropical soil solution, 100-mL aliquots of a dilute solution of oxalic acid in carbonated DI water were rained onto soils over a 14-day period to simulate soil moisture in the humid tropics. Solutions were collected and analyzed by ICPMS for concentrations of leached cations. A potential ERW scenario for Costa Rica was assessed assuming that one-half of lowland agricultural kaolinitic soils (mainly Ultisols, common crop and pasture soils, excluding protected areas) were to receive 50 t ha-1 of annual or biennial applications of powdered mafic rock. With an experimentally determined humid tropical CDR rate for basaltic andesite (3.5 t ha-1 yr-1) and allowances for carbon costs (e.g. emissions from processing and delivery) that reduce CDR to a net 3.2 t ha-1 yr-1, potential annual CDR of this tropical nation is ∼2-4 million tons, amounting to ∼25-50 % of annual CO2 emissions (mainly from transportation in Costa Rica).

2.
Rev. bras. educ. espec ; 18(3): 361-374, jul.-set. 2012. tab
Article in English | LILACS | ID: lil-658097

ABSTRACT

The purpose of this study was to examine the effect of practicum experiences on pre-professional physical education teachers' intentions toward working with individuals with disabilities. Pre-professional physical education teachers were students in their respective university's PETE programs and were categorized based on level of practicum experience. Over a three year period, a total of 596 PETE students completed the Physical Educators' Intention toward Teaching Individuals with Disabilities (PEITID) questionnaire (Rizzo, 2007). Significant differences were found among groups for overall intention to teach students with disabilities in their general physical education classroom. Additionally, trends of more positive intentions among pre-professionals with greater practicum experiences lead to higher Quality of Experience and Perceived Competence. The results of this study indicated that the level and quality of practicum experience significantly influence pre-professional teachers' intentions and competence toward teaching individuals with disabilities. (138 words).


O objetivo deste estudo foi examinar o efeito de experiências práticas nas intenções dos professores de educação física não capacitados com relação ao trabalho com pessoas com deficiência. Participaram da pesquisa professores de educação física matriulados como estudantes em programas de capacitação (PETE) em suas respectivas universidades, categorizados com base no nível de experiência prática. Num período de três anos, 596 alunos PETE preencheram o questionário PEITID - Physical Educators' Intention toward Teaching Individuals with Disabilities (Rizzo, 2007). Foram encontradas diferenças significativas entre os grupos que tinham a intenção de ensinar alunos com deficiência em turmas regulares de educação física. Além disso, as intenções mais positivas entre os professores não capacitados com mais experiência prática se relacionam com a maior Qualidade de Experiência e Competência por eles Percebida. Os resultados deste estudo indicaram que o nível e a qualidade da experiência prática influenciaram significativamente nas intenções dos professores não capacitados e na competência para o ensino de pessoas com deficiência.

5.
Plant Dis ; 93(6): 674, 2009 Jun.
Article in English | MEDLINE | ID: mdl-30764417

ABSTRACT

Michoacan State is the largest producer of blackberries (Rubus fruticosus) in Mexico with more than 4,000 ha in production. During the rainy season of 2007 (July to September), purple, angular, vein-delimited leaf spots along the midrib and major veins were observed. Affected young fruit lost their shine, became shriveled, and later dried. Some fruit split. Symptomatic leaflets from cv. Tupy were collected from the field in Tangancicuaro and Los Reyes counties. In the laboratory, 20 detached leaflets were washed with 10% bleach for 2 min, rinsed with sterile distilled water, and placed into sterile petri dishes containing 0.5% water agar. To promote sporulation of fungi, leaflets were incubated at 17°C with a 12-h photoperiod in a growth chamber. Sporangia and sporangiophores, which developed 20 days later on the underside of the leaves, were transferred to the underside of detached healthy leaves of the same cultivar with a sterile needle, and incubated as previously described. A set of noninoculated leaves were included as controls. Sporangiophores and sporangia developed on the underside of angular purple lesions on leaves 15 to 22 days after inoculation. Symptoms were identical to those observed on leaves in the field. The pathogenicity test was repeated twice with the same results. Sporangia were light brown, ovoid to elliptical, and measured 14 to 22 × 11 to 18 µm. Sporangiophores were dichotomously branched with slender curved ends. Symptoms on the leaves and fruit and oomycete morphology were similar to those described for downy mildew (2). To confirm pathogen identity, a product of ~500 bp of the nuclear ITS-rRNA was amplified from total DNA from symptomatic and asymptomatic leaves and fruit by nested PCR. The primers sets PS3/PS1 and PR3/PR4 were used for the first and second reaction, respectively (1,3). PCR products were sequenced in both directions and sequences were deposited in GenBank under Accession Nos. EU601168, EU601169, EU601170, and EU601171. Consensus sequences obtained in this study were compared with the same region of Peronospora sparsa (GenBank Accession Nos. EU391654 from Denmark and AF266783 from the UK). Similarity among these sequences varied between 99 and 100%. To our knowledge, this is the first report of downy mildew (dryberry) of blackberry caused by P. sparsa in Mexico. References: (1) B. J. Aegerter et al. Plant Dis. 86:1363, 2002. (2) W. D. Gubler. Page 15 in: Compendium of Raspberry and Blackberry Diseases and Insects. M. A. Ellis et al., eds. The American Phytopathological Society, St Paul MN, 1998. (3) H. Lindqvist et al. Plant Dis. 82:1304, 1998.

6.
West Indian med. j ; West Indian med. j;57(2): 161-165, Mar. 2008.
Article in English | LILACS | ID: lil-672326

ABSTRACT

Emergency Medicine in Jamaica has evolved rapidly over the past 20 years and has gained recognition as a specialty. A residency training programme has been established, trademark life support courses are now available, moves to develop areas of sub-specialization have begun and an emergency medicine association has been formed. There has been an increase in the diagnostic modalities in the main teaching institution, the University Hospital of the West Indies (UHWI). There is an urgent need for improvements in pre-hospital care. This will require the development of an efficient Emergency Medical Service (EMS). More emphasis and attention is required on disaster medicine, toxicology and trauma. Increased training of emergency physicians and nurses, advances in academia and research, and greater advocacy by local emergency physicians will further advance the specialty.


La medicina de emergencia en Jamaica ha evolucionado rápidamente en el curso de los últimos 20 años, y ha ganado reconocimiento como especialidad. Se ha establecido un programa de entrenamiento de residencia, y existen en la actualidad cursos comerciales en soporte de vida, se han iniciado movimientos para desarrollar áreas de sub-especialización, y se ha creado una asociación de medicina de emergencia. Ha habido un aumento en las modalidades de diagnóstico en la principal institución docente - el Hospital Universitario de West Indies (UHWI). Existe una necesidad urgente de lograr mejoras en el cuidado pre-hospitalario. Esto requerirá el desarrollo de Servicios Médicos de Emergencia (SME) eficientes. Se requiere más énfasis y atención a la medicina de desastre, toxicología y trauma. El aumento de entrenamiento de médicos y enfermeras de emergencia, los avances en la academia y la investigación, y una mayor defensa de los médicos de emergencia local, contribuirán al ulterior progreso de la especialidad.


Subject(s)
Humans , Emergency Medicine/education , Emergency Medicine/organization & administration , Disaster Planning , Emergency Medical Services/organization & administration , Emergency Medical Services/trends , Emergency Medicine/trends , Hospitals, Teaching , Internship and Residency , Jamaica , Poison Control Centers
7.
West Indian Med J ; 57(2): 161-5, 2008 Mar.
Article in English | MEDLINE | ID: mdl-19565961

ABSTRACT

Emergency Medicine in Jamaica has evolved rapidly over the past 20 years and has gained recognition as a specialty. A residency training programme has been established, trademark life support courses are now available, moves to develop areas of sub-specialization have begun and an emergency medicine association has been formed. There has been an increase in the diagnostic modalities in the main teaching institution, the University Hospital of the West Indies (UHWI). There is an urgent need for improvements in pre-hospital care. This will require the development of an efficient Emergency Medical Service (EMS). More emphasis and attention is required on disaster medicine, toxicology and trauma. Increased training of emergency physicians and nurses, advances in academia and research, and greater advocacy by local emergency physicians will further advance the specialty.


Subject(s)
Emergency Medicine/education , Emergency Medicine/organization & administration , Disaster Planning , Emergency Medical Services/organization & administration , Emergency Medical Services/trends , Emergency Medicine/trends , Hospitals, Teaching , Humans , Internship and Residency , Jamaica , Poison Control Centers
8.
Plant Dis ; 91(12): 1625-1637, 2007 Dec.
Article in English | MEDLINE | ID: mdl-30780602

ABSTRACT

Sensitivities of 89 isolates of Phytophthora cactorum, the causal agent of crown rot and leather rot on strawberry plants, from seven states (Florida, Maine, North Carolina, Ohio, Oregon, South Carolina, and New York) to the QoI fungicide azoxystrobin were determined based on mycelium growth and zoospore germination. Radial growth of mycelia on lima bean agar amended with azoxystrobin at 0.001, 0.01, 0.1, 1.0, 10, and 30 µg/ml and salicylhydroxamic acid (SHAM) at 100 µg/ml was measured after 6 days. Effect on zoospore germination was evaluated in aqueous solutions of azoxystrobin at 0.005, 0.01, 0.05, 0.1, 0.5, and 1.0 µg/ml in 96-well microtiter plates by counting germinated and nongerminated zoospores after 4 h at room temperature. SHAM was not used to evaluate zoospore sensitivity. The effective dose to reduce mycelium growth by 50% (ED50) ranged from 0.16 to 12.52 µg/ml for leather rot isolates and 0.10 to 15 µg/ml for crown rot isolates. The Kolmogorov-Smirnov test showed significant differences (P < 0.001) between the two distributions. Zoospores were much more sensitive to azoxystrobin than were mycelia. Differences between sensitivity distributions for zoospores from leather rot and crown rot isolates were significant at P = 0.05. Estimated ED50 values ranged from 0.01 to 0.24 µg/ml with a median of 0.04 µg/ml. Experiments with pyraclostrobin, another QoI fungicide, demonstrated that both mycelia and zoospores of P. cactorum were more sensitive to pyraclostrobin than to azoxystrobin. Sensitivities to azoxystrobin and pyraclostrobin were moderately but significantly correlated (r = 0.60, P = 0.0001).

9.
Arch. med. interna (Montevideo) ; 27(1): 12-20, mar. 2005. tab
Article in Spanish | LILACS | ID: lil-463076

ABSTRACT

La hipertensión portal es responsable de las principales complicaciones de la cirrosis y la hemorragia digestiva por rotura de várices esófago-gástricas es consecuencia directa de la misma. Gracias al desarrollo de nuevos fármacos, técnicas endoscópicas y quirúrgicas, incluido el traspalnte hepático, las estrategias de tratamiento de esta complicación han evolucionado en los últimos 20 años. En esta revisión se analizan y presentan los principales datos y conclusiones al respecto, considerando las siguientes situaciones: profilaxis primaria, hemorragia digestiva en curso, profilaxis secundaria.


Subject(s)
Humans , Esophageal and Gastric Varices , Gastrointestinal Hemorrhage , Hypertension, Portal/complications , Esophagoscopy , Sclerotherapy
10.
J Anim Sci ; 83(1): 75-81, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15583045

ABSTRACT

Blood acid-base responses to handling were evaluated in slaughter weight pigs fed diets supplemented with l-carnitine and fat. The study was carried out as a randomized block design with a 2 x 2 factorial arrangement of treatments: 1) dietary L-carnitine supplementation (0 vs. 150 ppm, as-fed basis); and 2) dietary fat supplementation (0 vs. 5%, as-fed basis). Sixty pigs (91.1 +/- 5.14 kg BW) were housed in mixed-gender groups of five and had ad libitum access to test diets (0.68% true ileal digestible lysine, 3,340 kcal of ME/kg, as-fed basis) for 3 wk. At the end of the feeding period (110.3 +/- 7.52 kg BW), pigs were subjected to a standard handling procedure, which consisted of moving individual animals through a facility (12.2 m long x 0.91 m wide) for eight laps (up and down the facility), using electric prods (two times per lap). There was no interaction between dietary L-carnitine and fat supplementation for any measurement. Pigs fed 150 ppm of supplemental L-carnitine had lower baseline blood glucose (P < 0.05) and higher baseline blood lactate (P < 0.05) concentrations than the nonsupplemented pigs. After handling, pigs fed L-carnitine-supplemented diets had a higher (P < 0.05) blood pH and showed a smaller (P < 0.05) decrease in blood pH and base excess than those fed the nonsupplemental diets. Baseline plasma FFA concentrations were higher (P < 0.01) in pigs fed the 5% fat diet. After the handling procedure, blood glucose, lactate, and plasma FFA were higher (P < 0.05) in pigs fed the 5 vs. 0% fat diets, but blood pH, bicarbonate, and base excess were not affected by dietary fat. The handling procedure decreased (P < 0.01) blood pH, bicarbonate, base excess, and total carbon dioxide and increased (P < 0.01) blood lactate, partial pressure of oxygen, and glucose, and also increased (P < 0.01) rectal temperature. Free fatty acid concentrations were increased by handling in pigs fed both 0 and 5% fat and 150 ppm L-carnitine. In conclusion, dietary L-carnitine supplementation at the level and for the feeding period evaluated in the current study had a relatively small but positive effect on decreasing blood pH changes in finishing pigs submitted to handling stress; however, dietary fat supplementation had little effect on blood acid-base balance.


Subject(s)
Acid-Base Equilibrium/drug effects , Carnitine/pharmacology , Dietary Fats/pharmacology , Dietary Supplements , Handling, Psychological , Swine/physiology , Adipose Tissue/diagnostic imaging , Animal Feed/analysis , Animals , Blood/drug effects , Blood Chemical Analysis/veterinary , Blood Gas Analysis/veterinary , Body Temperature/drug effects , Body Temperature/physiology , Carnitine/administration & dosage , Dietary Fats/administration & dosage , Female , Hydrogen-Ion Concentration/drug effects , Male , Meat/standards , Random Allocation , Swine/blood , Ultrasonography
11.
Plant Dis ; 84(2): 199, 2000 Feb.
Article in English | MEDLINE | ID: mdl-30841318

ABSTRACT

Babaco, Carica × heilbornii V.M. Badillo var. pentagona (Heilborn) V.M. Badillo, is a fruit native to Ecuador that has great potential as a cultivated crop. Local market demand and strong potential as an export crop have greatly increased interest in babaco production in Ecuador. Although the crop can be produced in open fields, the majority of crop production is in plastic greenhouses. In 1996, a serious wilt disease developed on babaco in several greenhouses, resulting in up to 100% loss of plants. Symptoms first appeared as chlorosis of the lower leaves, followed by defoliation progressing up the stem until the entire plant was defoliated. When cut in cross section, vascular discoloration was observed in the stem. Eventually necrosis and soft rot of the stem occurred and entire plants collapsed. Fungal isolations were conducted from fine feeder roots of diseased plants by soaking root pieces (2 cm long) in a 0.5% solution of sodium hypochlorite for 3 min. Root pieces were cut into smaller sections and placed on potato dextrose (PDA) or corn meal (CMA) agar in petri dishes. Isolations from larger roots, crowns, stems and fruits were made by soaking tissue sections of each plant part in a 2.87% solution of sodium hypochlorite for 3 min. Tissue sections were rinsed three times in sterile distilled water. Smaller tissue sections (≈0.125 cm3) were cut from surface-disinfested pieces and placed on PDA and CMA in petri dishes. Cultures were incubated at 20°C. A fungus resembling Fusarium sp. was isolated consistently from infected tissues from all infected plant parts. Based on the morphology of the fungal colony and conidia from monosporic isolations, the fungus was identified as Fusarium oxysporum Schlechtend:Fr. (1). Pathogenicity tests were conducted by growing babaco plants in pots containing an equal mixture of sterilized soil, compost, and sand in the greenhouse. Eight 7-month-old plants were inoculated by placing 40 ml of a suspension (106 conidia per ml) of F. oxysporum in four plastic straws placed in the soil (5 cm depth) at equal distances (5 cm) from the base of each plant. Straws around noninoculated control plants received sterile water. Plants were watered with 400 ml of sterile water daily. Pathogenicity tests were repeated once as described. All inoculated plants developed typical wilt symptoms within 45 days after inoculation. No symptoms developed on uninoculated control plants. F. oxysporum was successfully reisolated from infected stem tissues of inoculated plants. Incidence of Fusarium vascular wilt of babaco has continued to increase since 1996 and is currently the major constraint to production. References: (1) P. E. Nelson et al. 1981. Fusarium: Diseases, Biology, and Taxonomy. The Pennsylvania State University Press, University Park.

12.
Int Migr ; 34(1): 31-64, 1996.
Article in English | MEDLINE | ID: mdl-12291795

ABSTRACT

"The purpose of this paper has been to outline a theoretical framework for the explanation of the circulation of Puerto Rican women that brings gender relations to the fore, but frames the island-mainland pattern of mobility in the context of core-periphery capitalist relations. We have argued that gender relations in the home and workplace are vitally important for understanding women's moves to the [United States] and return trips to Puerto Rico. Specifically, we posited that most Puerto Rican women move as tied-migrants or because of their obligation or desire to meet gender responsibilities. In addition, we also viewed migration as an action with the potential to modify gender relations and alter future migration decision-making, as women gain experience in the labour market and exposure to new social and cultural environments." (SUMMARY IN FRE AND SPA)


Subject(s)
Decision Making , Emigration and Immigration , Motivation , Sex Factors , Social Change , Transients and Migrants , Women's Rights , Americas , Behavior , Caribbean Region , Demography , Developed Countries , Developing Countries , Economics , Latin America , North America , Population , Population Characteristics , Population Dynamics , Psychology , Puerto Rico , Socioeconomic Factors , United States
13.
Circulation ; 92(3): 371-9, 1995 Aug 01.
Article in English | MEDLINE | ID: mdl-7634451

ABSTRACT

BACKGROUND: Continuous intravenous administration of adenosine to humans often results in a paradoxical rise in pulmonary capillary wedge pressure (PCWP), whereas arterial resistance is lowered and cardiac output and heart rate increase. This is believed to be due to diastolic stiffening of the ventricle or to a negative inotropic effect. In the present study, we tested these and other mechanisms by using pressure-volume (PV) analysis and echocardiography. METHODS AND RESULTS: Fifteen patients with normal rest left ventricular function underwent cardiac catheterization and received adenosine at a rate of 140 micrograms/kg per minute IV for 6 to 10 minutes. PV relations were measured in 9 patients (without coronary artery disease) using the conductance catheter method. In 6 additional patients with coronary artery disease, echocardiograms were used to assess wall thickness and function, and aortic and coronary sinus blood, lactate, oxygen, and adenosine levels were measured. Adenosine increased PCWP by 19% (+2.6 mm Hg) in both patient groups while lowering arterial load by 30% and increasing cardiac output by 45% (all P < .001). There was no significant effect of adenosine on mean linear chamber compliance or monoexponential elastic stiffness, as the diastolic PV relation was unchanged in most patients. Diastolic wall thickness also was unaltered. Thus, the PCWP rise did not appear to be due to diastolic stiffening. Adenosine induced a rightward shift of the end-systolic PV relation (ESPVR) (+12.7 +/- 3.7 mL) without a slope change. This shift likely reflected effects of afterload reduction, as other indexes (stroke work-end-diastolic volume relation and dP/dtmax at matched preload) were either unchanged or increased. Furthermore, this modest shift in ESPVR was more than compensated for by vasodilation and tachycardia, so reduced systolic function could not explain the increase in PCWP. There also was no net lactate production to suggest ischemia. Rather than arising from direct myocardial effects, PCWP elevation was most easily explained by a change in vascular loading, as both left ventricular end-diastolic volume and right atrial pressure increased (P < .05). This suggests that adenosine induced a redistribution of blood volume toward the central thorax. CONCLUSIONS: PCWP elevation in response to adenosine primarily results from changes in vascular loading rather than from direct effects on cardiac diastolic or systolic function.


Subject(s)
Adenosine/administration & dosage , Pulmonary Wedge Pressure/drug effects , Coronary Disease/physiopathology , Echocardiography , Hemodynamics , Humans , Lung/blood supply
15.
Geoforum ; 21(1): 51-66, 1990.
Article in English | MEDLINE | ID: mdl-12316661

ABSTRACT

Aspects of migration between Puerto Rico and the United States are explored. "This examination of the multiple-movement behaviour of a sample of Puerto Rican women seeks to unravel the relations between their circulation patterns, their family and contextual situations and their declared motives for undertaking international mobility. The leading question asked in this study is whether this international mobility behaviour of Puerto Rican women is autonomous or dependent upon the movement or decision-making of others. Structural theory suggests the latter is most likely, but behavioural divergence occurs in return movement."


Subject(s)
Emigration and Immigration , Women's Rights , Americas , Caribbean Region , Demography , Developed Countries , Developing Countries , Economics , Latin America , North America , Population , Population Dynamics , Puerto Rico , Socioeconomic Factors , United States
17.
Br Med J (Clin Res Ed) ; 292(6527): 1048-9, 1986 Apr 19.
Article in English | MEDLINE | ID: mdl-3083997
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