A solar cycle lost in 1793--1800: Early sunspot observations resolve the old mystery

Because of the lack of reliable sunspot observation, the quality of sunspot number series is poor in the late 18th century, leading to the abnormally long solar cycle (1784--1799) before the Dalton minimum. Using the newly recovered solar drawings by the 18--19th century observers Staudacher and Hamilton, we construct the solar butterfly diagram, i.e. the latitudinal distribution of sunspots in the 1790's. The sudden, systematic occurrence of sunspots at high solar latitudes in 1793--1796 unambiguously shows that a new cycle started in 1793, which was lost in traditional Wolf's sunspot series. This finally confirms the existence of the lost cycle that has been proposed earlier, thus resolving an old mystery. This letter brings the attention of the scientific community to the need of revising the sunspot series in the 18th century. The presence of a new short, asymmetric cycle implies changes and constraints to sunspot cycle statistics, solar activity predictions, solar dynamo theories as well as for solar-terrestrial relations.Comment: Published by Astrophys. J. Let

A new subspecies of Orthotylus junipericola Linnavuori, 1965 (Insecta, Heteroptera) from the Azores.

Orthotylus (Parapachylops) junipericola attilioi n.ssp. is described from Terceira (Azores), based on a single male specimen collected in the Azorean endemic tree Juniperus brevifolia. O. (Parapachylops) junipericola Linnavuori, 1965 is a “Rassenkreis” with seven known geographic races with an Atlanto-mediterranean distribution. O. (Parapachylops) junipericola attilioi n.ssp. is the eighth subspecies described from this species, being the most occidental taxon. The new subspecies, O. (Parapachylops) junipericola attilioi n.ssp., was sampled in a biodiversity hotspot from the Azores, Biscoito da Ferraria Natural Forest Reserve of “climax pattern of indigenous forest”

Assessment of the Accuracy of a Multi-Beam LED Scanner Sensor for Measuring Olive Canopies

MDPI. CC BYCanopy characterization has become important when trying to optimize any kind of agricultural operation in high-growing crops, such as olive. Many sensors and techniques have reported satisfactory results in these approaches and in this work a 2D laser scanner was explored for measuring canopy trees in real-time conditions. The sensor was tested in both laboratory and field conditions to check its accuracy, its cone width, and its ability to characterize olive canopies in situ. The sensor was mounted on a mast and tested in laboratory conditions to check: (i) its accuracy at different measurement distances; (ii) its measurement cone width with different reflectivity targets; and (iii) the influence of the target’s density on its accuracy. The field tests involved both isolated and hedgerow orchards, in which the measurements were taken manually and with the sensor. The canopy volume was estimated with a methodology consisting of revolving or extruding the canopy contour. The sensor showed high accuracy in the laboratory test, except for the measurements performed at 1.0 m distance, with 60 mm error (6%). Otherwise, error remained below 20 mm (1% relative error). The cone width depended on the target reflectivity. The accuracy decreased with the target density

On the novel free porphyrins corallistin B, C, D, and E : isolation from the demosponge Corallistes sp. of the Coral Sea and reactivity of their nickel (2) complexes toward formylating reagents

Reported here are the novel free corallistin B, C, D, and E, isolated as methyl esters 2a, 3a, 4a, and 5a, respectively, from the sponge #Corallistes sp.(#Lithistida) collected at the basis of the South New Caledonian coral reef. A protocol is also established for formulation of their NiII complexes, which show a different reactivity pattern toward DMF/POCI3 from metal complexes of deuteroporphyrin IX (isolate as 6a) also present in the sponge, the new corallistins, which may be thought to derive from protoporphyrin via heme, account for an amazing 60% of the etOH extract from the sponge. (Résumé d'auteur

Sponges and ascidians control removal of particulate organic nitrogen from coral reef water

10 pages, 5 figures, 5 tables.-- This is HIMB contribution 1199 and SOEST contribution 6596We studied removal rates of plankton and total particulate organic nitrogen (PON) by benthic reef communities from the overlying water in a large experimental flume. The flume was filled with mixtures of coral and coral rubble, and biomass of plankton was measured as water was recirculated over the experimental benthic community. All planktonic particle types, picoplankton, nanoplankton, microplankton, and total PON, decreased in concentration at rates proportional to their biomass. The mean first-order rate constant for the decrease in particle concentration was 96 ± 61 × 10-6 m s-1, corresponding to PON uptake of 10 mmol N m-2 d -1. Synechococcus sp. and heterotrophic bacteria were the major sources of PON. Particulate organic nitrogen removed by rubble and live coral assemblages was directly related to sponge and ascidian biomass (number and area) on the coral and coral rubble. Uptake of PON was about the same as the previously measured uptake of dissolved inorganic nitrogen into these coral reef communities, making it an important flux of nitrogen into the reef. © 2005, by the American Society of Limnology and Oceanography, Inc.Support for this work was provided by a postdoctoral fellowship from the Ministerio de Educación y Cultura (MEC) and a Ramón y Cajal research contract to M.R. This paper was funded in part by NOAA project R/CR-1, which is sponsored by the University of Hawaii Sea Grant College Program, School of Ocean and Earth Science Technology (SOEST), under grant NA 86RG0041. Additional funding was provided by CISNet (NOAA project NA 870A0531) and TransCom (Transfer at Community level) project (REN2002-01631/MAR)Peer Reviewe

The Dynamic Formation of Prominence Condensations

We present simulations of a model for the formation of a prominence condensation in a coronal loop. The key idea behind the model is that the spatial localization of loop heating near the chromosphere leads to a catastrophic cooling in the corona (Antiochos & Klimchuk 1991). Using a new adaptive grid code, we simulate the complete growth of a condensation, and find that after approx. 5,000 s it reaches a quasi-steady state. We show that the size and the growth time of the condensation are in good agreement with data, and discuss the implications of the model for coronal heating and SOHO/TRACE observations.Comment: Astrophysical Journal latex file, 20 pages, 7 b-w figures (gif files

Agelastatin A, a new skeleton cytotoxic alkaloid of the oroidin family : isolation from the Axinellid sponge Agelas dendromorpha of the Coral Sea

Agelastatin A, isolated from the axinellid sponge #Agelas dendromorpha$ of the Coral Sea, is a new skeleton alkaloid with, unusually for the oroidin family to which it belongs, marked cytototoxicity toward tumour cells in culture. (Résumé d'auteur