Measuring the effective focal length and shape factor of a thick lens using a microscope

The optical power of a thick spherical lens and its Coddington shape factor are essential magnitudes that characterize its image quality. Here, we propose an experimental procedure and apparatus that allow accurate determination of those magnitudes for any spherical lens from geometrical measurements. The performance of the technique and the used instruments are simple since it only requires a microscope and an optical mouse. The propose overcomes the drawbacks of other devices that need of the refractive index or may damage the lens surfaces, like spherometers, and provides similar results to those from commercial lensmeters.

Endophytic colonization of barley (Hordeum vulgare) roots by the nematophagous fungus Pochonia chlamydosporia reveals plant growth promotion and a general defense and stress transcriptomic response

Plant crop yields are negatively conditioned by a large set of biotic and abiotic factors. An alternative to mitigate these adverse effects is the use of fungal biological control agents and endophytes. The egg-parasitic fungus Pochonia chlamydosporia has been traditionally studied because of its potential as a biological control agent of plant-parasitic nematodes. This fungus can also act as an endophyte in monocot and dicot plants, and has been shown to promote plant growth in different agronomic crops. An Affymetrix 22K Barley GeneChip was used in this work to analyze the barley root transcriptomic response to P. chlamydosporia root colonization. Functional gene ontology (GO) and gene set enrichment analyses showed that genes involved in stress response were enriched in the barley transcriptome under endophytism. An 87.5 % of the probesets identified within the abiotic stress response group encoded heat shock proteins. Additionally, we found in our transcriptomic analysis an up-regulation of genes implicated in the biosynthesis of plant hormones, such as auxin, ethylene and jasmonic acid. Along with these, we detected induction of brassinosteroid insensitive 1-associated receptor kinase 1 (BR1) and other genes related to effector-triggered immunity (ETI) and pattern-triggered immunity (PTI). Our study supports at the molecular level the growth-promoting effect observed in plants endophytically colonized by P. chlamydosporia, which opens the door to further studies addressing the capacity of this fungus to mitigate the negative effects of biotic and abiotic factors on plant crops.

Computing the zeros of the partial sums of the Riemann zeta function

In this paper, we introduce a formula for the exact number of zeros of every partial sum of the Riemann zeta function inside infinitely many rectangles of the critical strips where they are situated.

Avignon, France, ca. 1618 (Raster Image)

This layer is a georeferenced raster image of the historic paper map entitled: Civitatis Avenionis omni[u]mq. viarum et aedificiorum eius perfecta delineatio hoc anno MCCXVIII. It was published ca. 1618. Scale [ca. 1:1,500]. Map in Latin. Covers Avignon, France. The image inside the map neatline is georeferenced to the surface of the earth and fit to the European Datum 1950, Universal Transverse Mercator (UTM) Zone 31N projected coordinate system. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as roads, drainage, built-up areas and selected buildings, fortifications, ground cover, and more. Relief shown pictorially.This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection. These maps typically portray both natural and manmade features. The selection represents a range of originators, ground condition dates, scales, and map purposes.

Stable oxygen isotope record of planktonic foraminifera from late Quaternary sediments of the equatorial Pacific

Planktonic foraminiferal test fragmentation in three cores along a depth transect from the western equatorial Pacific (ERDC-93P, 1619 m; RC17-177, 2600 m; V28-238, 3120 m [Thompson, 1976]) were examined for the last 500 kyr at sample intervals from 2.5 to 5 kyr to study the fluctuations of dissolution in the western equatorial Pacific. The age models were constructed by correlating the delta18O records with the SPECMAP stack [Imbrie et al., 1984]. Results showed that intermediate and deep waters experienced the same patterns of dissolution through climatic cycles. Fragmentation varied with a greater amplitude, and the carbonate ion concentration changed less, in the deep than in the intermediate water. Dissolution has significant variance distributions and coherencies with delta18O over the 100, 41, and 23 kyr periods of orbital variations; dissolution maxima lag ice volume minima by 6 to 20 kyr. The dissolution variability was consistent with recent geochemical models which seek to explain the reduction of atmospheric CO2 concentration at the last glacial maximum [Broecker, 1982; Boyle, 1988].

Remarks on the life and death of the fam'd Mr. Blood : giving an account [brace]of his plot in Ireland, to surprize Dublin Castle; several transactions in his head-quarters in the city; rescue of Captain Mason at Doncaster; attempt on the person of his Grace the Duke of Ormond; seizing on the crown and scepter in the Tower; coming into favour with his Prince; concern about his Grace the Duke of Buckingham; sickness, death, and twice interment : published for publick information.

Leaf A₂ mis-signed as A₁.

Histoire littéraire de la Congrégation de Saint-Maur, ordre de S. Benoît, où l'on trouve la vie & les travaux des auteurs qu'elle a produits, depuis son origine en 1618, jusqu'à présent:

Mode of access: Internet.

The shepheardes calender : conteining twelue aeglogues proportionable to the twelue monethes : Entitled to the noble and vertuous gentleman most worthie of all titles, both of learning and chiualry, Maister Philip Sidney.

Label inside front board.

The shepheards calender : conteining twelue æglogues proportionable to the twelue monthes : entituled, to the noble and vertuous gentleman, most worthie of all titles, both of learning and chiualry, Maister Philip Sidney.

Fourth edition.

Grotte, labyrinthe, fontaines et bassins de Versailles.

This volume has been designated "sixième volume" in the Catalogue, for a collection known under the title of the repository, Cabinet du roi. The engravings were prepared between 1672 and 1689 by various engravers: Le Pautre, Le Clerc, Chauveau, Edelinck, Picart, Baudet, Silvestre, Simonneau and Chatillon. They were issued individually at the outset, collected, and in this instance issued in uniform format. The plates of the Labyrinthe, 15 x 8.5 cm., have been printed on 4 leaves of 9 and 1 leaf of 5.

Lely & the Stuart portrait painters; a study of English portraiture before & after Van Dyck:

"Of this work 375 copies (of which 350 are for sale) have been printed on pure rag paper; also (for a subscriber) 30 copies (25 for sale) on hand-made paper, with an extra set of the plates. Of the ordinary edition this is no. 21."

The bibliography of Sir Walter Ralegh, knt.

Mode of access: Internet.

Fortescutus illustratus, or a commentary on that nervous treatise De laudibus legum Angliæ, written by Sir John Fortescue ... VVhich treatise ... hee purposely wrote to consolidate his princely minde in love and approbation of the good lawes of England and of the laudable customs of this his native country. The heroique design of whole excellent judgement and loyal addiction to his Prince, is humbly endeavoured to be revived, admired, and advanced.

Mode of access: Internet.