Phytoplankton species diversity of 27 lakes and ponds of Costa Rica (Central America)

The literature on species diversity of phytoplankton of tropical lakes is scarce, and for the main part comes from studies of the big lakes in Africa, or deep lakes in South America, leaving a gap in the information about small shallow tropical lakes. In the present work the phytoplankton species composition and diversity of 27 shallow lakes and ponds in Costa Rica (Central America) was studied. The species composition was found to agree with other studies of tropical lakes, with a dominance of Chlorophyta, Cyanophyta, or in some cases Bacillariophyta or Euglenophyta; and a general paucity of Chrysophyta and Cryptophyta. Species richness varied considerably among the lakes, and tended to decrease with an increase in lake elevation. A low evenness in the species abundances was found, with one or more species outnumbering the rest by several orders of magnitude. Individual species abundances and species composition was found to vary with time in Rio Cuarto Lake, a meromictic lake situated in a region with low seasonal change in precipitation. In comparison with the phytoplankton of temperate lakes, the phytoplankton of the tropical lakes studied tended to have a lower evenness of species abundances, although species richness may be similar to temperate figures in some cases. Diversity indices sensitive to changes in the abundance of rare species tend to be higher in the tropical lakes studied; diversity indices sensitive to changes in the numbers of abundant species tend to be similar between the temperate and tropical lakes examined.

The effects of the menstrual cycle and hormonal contraceptives on the central thermoeffector threshold temperatures and width of the interthreshold zone

Basal body temperature (BBT) and thermoeffector thresholds increase following ovulation in many women. This study investigated if solely central thermoregulatory alterations are responsible. Seven females in a non-contraceptive group (NCG) were compared with 5 monophasic contraceptive users (HCG) on separate accounts: pre-ovulation (Trial I; d 2-5) and post-ovulation (Trial 2; 4-8 d post-positive ovulation) for NCG, and active phase for HCG (d 2-5, d 18-21). During immersion in 28°C water to the axilla, participants exercised for 20-30 min on an underwater ergometer. After steadily sweating, immersion continued until metabolism increased two-fold due to shivering. Rectal (Tre) BBT was not different between trials for neither NCG (1: 37.34±0.16°C; 2: 37.35±0.27°C) nor HCG. At exercise termination, Tre forehead sweating cessation increased (P<0.05) in trial 2 irrespective of group (1: 37.55±0.39°C; 2: 37.90±0,46°C). Tre shivering onset did not increase (P>0.05) in trial 2 (1: 36.91±0.50°C; 2: 37.07±0,45°C). The widths of the interthreshold zone increased (P<0.05) in trial 2 (1: 0.64±0.22°C; 2: 0.82±0.37°C) due to the increased sweating threshold only. HCG cooled quicker (1: -l.15±0,43°C; 2: -1.00±0.50°C) than NCG participants (1: - 0.58±0.22°C; 2: -0.52±O.29°C), and tympanic (Tty) sweat thresholds were significantly (P<0.05) decreased (1: 34.76±0.54°C; 2: 35.39±0.61°C) versus NCG (l: 35.57±0.77°C; 2: 35.89±1.04°C). Lastly, Tre and Tty thresholds were significantly different (Pcentral thermoregulatory drive for sweating is altered by menstrual phase, contraceptive users have enhanced thermal sensitivities, and Tty opposed to Tre provides different measures of core temperature.

CENTRAL NORTH ATLANTIC PALEOCEANOGRAPHY DURING THE MIDDLE PLEISTOCENE (ca. 726–603 ka): INSIGHTS FROM THE DINOFLAGELLATE CYST RECORD

Integrated Ocean Drilling Program (IODP) Site U1313, located at the northern boundary of the subtropical gyre in the central North Atlantic, lies within the southern part of the ice-rafted debris belt. Seventy-three palynological samples were studied from an uninterrupted interval ca. 726–603 ka (upper Marine Isotope Stage [MIS] 18 through lower MIS 15) to resolve conflicting paleoceanographic interpretations. Glacial stages were characterized by high productivity surface waters reflecting a southward shift of the Arctic Front. Sea surface salinities (SSSs) and sea surface temperatures (SSTs) were obtained by transfer functions using the Modern Analogue Technique. The lowest SSTs of 9ºC (±1.3) and 10ºC (±1.3) were recorded in glacial MIS 16 and MIS 18 respectively. However, these reconstructions are influenced by abundant heterotrophic taxa and may reflect elevated nutrient levels rather than lowered temperatures. Reworked palynomorphs uniquely indicate a Cretaceous as well as Paleozoic provenance for the first Heinrich-like events.

Grand Central Hotel Blueprints

Plans are alterations to store fronts and rear elevation.

DINOFLAGELLATE CYSTS FROM THE LATEST MIOCENE THROUGH MIDDLE PLEISTOCENE OF THE CARIBBEAN SEA, ODP SITE 1000: BIOSTRATIGRAPHY, PALEOCEANOGRAPHY, AND SHOALING OF THE CENTRAL AMERICAN SEAWAY

This is the first detailed study of organic-walled dinoflagellate cysts (dinocysts) and acritarchs for the latest Miocene–Middle Pleistocene of Ocean Drilling Program Site 1000 in the Caribbean Sea. Well-preserved and moderately diverse dinocysts and other palynomorphs reflect the interplay between neritic (carbonate-platform sourced) and oceanic species. The dinocyst biostratigraphy is tied to an existing marine isotope stratigraphy for the interval 5.5–2.2 Ma. For the interval 5.5–3.8 Ma, palynological samples are coupled to published sea-surface temperature estimates based on planktonic foraminiferal Mg/Ca. Changes in dinocyst assemblage composition are noted at ca. 4.6 Ma when shoaling of the Central American Seaway caused a temperature rise in the Caribbean, ca. 3.8–3.6 Ma, during the cold Marine Isotope Stage M2 when pronounced warming occurred, at ca. 2.7 Ma where possible weak cooling may reflect the onset of Northern Hemisphere glaciation, and in the Middle Pleistocene presumably reflecting global cooling and sea-level fall.

Central Europe Labels

A selection of European alcohol labels, including: Grandezza Dansk Frugivinsfabrikat, Max and Moritz Perlwein, Gumpoldskirchner Konigswein Neuburger, Jisenski Biser.

Indenture between The St. Catharines and Niagara Central Railway Company and Samuel DeVeaux Woodruff

Indenture of deed of land situate between The St. Catharines and Niagara Central Railway Company and Samuel DeVeaux Woodruff of St. Catharines regarding parts of Lots no. 12 and 13 30 in the 8th Concession of the Township of Grantham. This was registered at Merritton on Feb. 2, 1891 – instrument no. 1021, Aug. 16, 1890.

Michigan Central Railway to S.D. Woodruff

Letter from the Michigan Central Railway to S.D. Woodruff regarding the construction of a fence, June 16, 1883.

Approximate estimate of the cost of completing the Port Dalhousie Railway to the Grand Central Railway Station at Lock 12

Approximate estimate of the cost of completing the Port Dalhousie Railway to the Grand Central Railway Station at Lock 12. This document is badly torn and burned but most of the text is legible, July 14, 1854.

Printed blank from the New York Central and Hudson River Railroad Express Freight Line, New York for shipping packages of brackets and racks to S.D. Woodruff of St. Catharines

Printed blank from the New York Central and Hudson River Railroad Express Freight Line, New York for shipping packages of brackets and racks to S.D. Woodruff of St. Catharines. This document is signed by R.L. Crawford, agent, Aug.11, 1876.

Receipt from N.R. MacGregor, Central Fruit Depot, St. Catharines

Receipt from N.R. MacGregor, Central Fruit Depot, St. Catharines for chickens, March 30, 1887.

Receipt from N.R. Macgregor, Central Fruit Depot, St. Catharines for groceries

Receipt from N.R. Macgregor, Central Fruit Depot, St. Catharines for groceries, July 22, 1887.

Influencia del sistema nervioso central en los mecanismos de la coagulación sanguínea en perros

Tesis (Maestría en Ciencias con Especialidad en Fisiología Médica) UANL

Perfusión de grandes dosis de insulina hacia arteria central de la retina

Tesis (Maestría en Ciencias) UANL

Desarrollo de procedimientos operativos del equipo de una central termoeléctrica y mejoras al sistema de gobierno en turbinas

Tesis (Maestría en Ciencias de la Ingeniería Mecánica con Especialidad en Térmica y Fluídos) UANL