Seixas family papers, undated, 1746-1911, 1926, 1939.

The collection contains items relating to individual members of the family as well as the Seixas family in general. Included are papers of the following persons: Isaac Mendes Seixas (1708/9-1780/1), a copy of A voyage to Hudson's--Bay, by Henry Ellis, inscribed with his name on the title page, along with additional inscriptions on the end papers (1748); and a daily prayer book printed in Amsterdam (title page missing), with an inscription on the first page indicating that the book was owned by Seixas in 1758/9, and subsequently by his grandson, Theodore J. Seixas, in 1816/17.

Judah P. Benjamin collection, undated, 1838-1942.

The collection consists of 25 letters written by Benjamin between 1838 and 1881 on a variety of subjects, four Confederate notes and two bonds bearing his picture, miscellaneous items about Benjamin (1893-1942), nine issues of the Congressional globe with speeches by Benjamin, as well as separate copies of his printed speeches, and a photostatic copy of the "Diary of Events" (400 pp.) kept by Benjamin, the original of which is in the Library of Congress (1862-1864).

Franks family papers, 1711-1821, [1965-1968].

Contains business correspondence, accounts and documents relating to Jacob Franks of New York, his two sons, Moses and David, a nephew, Isaac, and a John Franks of Halifax, possibly a member of the family.

Aaron Lopez papers, undated, 1752-1794, 1846, 1852, 1953.

Contains approximately 6800 manuscripts arranged chronologically by year for years 1752-1794. Approximately 100 are letters received or written by Lopez, his partner and father-in-law, Jacob Rodriguez Rivera, members of his family and company, and commercial agents pertaining to business activities and sailing orders for the captains of various ships. Several also refer to personal matters and acquaintances, including a series of six letters from Silas Cooke of White Hall (Middletown), R.I., to Aaron Lopez, asking his aid in returning a run-away slave (1776). The great majority of the collection consists of account records, bills of sale, orders, shipping agreements, lists of sailors on the various ships, repair records and cargo invoices. Of particular interest are a receipt for payment of a half-year's subscription to the "tzedakah" of Congregation Nefutzei Israel, Newport (1755) and several documents that reveal Lopez as a supplier of kosher meat and other religious articles to people in various parts of the colonies, Surinam, and Jamaica. Also included in this group are copies of sailing lists, documents pertaining to Lopez's naturalization which shed light upon the status of a Jew applying for citizenship in Massachusetts and a check to Lopez from the United States government for a loan made during the Revolutionary War (1779).

Descendants of Benjamin Seixas

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Petition of Benjamin Jacobs to Hayman Levy to marry a non-Jew

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Copy of letter sent to Benjamin Pereira at Jamaica engaging him as teacher in K. K. S. I.

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Letter from Isaac Seixas to Hayman Levy on proposed marriage of Benjamin Seixas to Zipporah Levy

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Notice of election of Benjamin Nathan

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Directional dominance on stature and cognition in diverse human populations

Homozygosity has long been associated with rare, often devastating, Mendelian disorders1, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness2. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power3, 4. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runs of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 × 10−300, 2.1 × 10−6, 2.5 × 10−10 and 1.8 × 10−10, respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months’ less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples5, 6, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection7, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.

"Ei kansa elä vain leivästä" : Suomen Taideyhdistys ja kuvataiteen kannattajakunnan muotoutuminen Helsingissä 1846-1865.

Tutkielma käsittelee kuvataideyleisön muotoutumista Suomen Taideyhdistyksen piirissä 1800-luvun puolivälissä sosiaalihistoriallisesta näkökulmasta. Tärkein lähdemateriaali on Suomen Taideyhdistyksen arkisto, jonka avulla tarkastellaan laajemmin yhdistyksen ideaa, sen jäsenyyttä, maanlaajuista jäsenkartuntaa ja johtokunnan taiteen kannattajiin suuntaamaa missiota toiminnan alkuvuosikymmeninä. Yhdistyksen helsinkiläinen jäsenistö vuosina 1846−1865 on luokiteltu kymmeneen luokkaan jäsenluettelossa annettujen nimikkeiden perusteella. Lähdeaineiston ja sen pohjalta tehdyn luokittelun avulla analysoidaan pääkaupungin jäsenkuntaa ja sen suhdetta koko maan jäsenistöön. Jäsenkunnasta nostetaan esille myös joitakin kiinnostavia yksilöitä. Tutkielman pääasiallinen teoreettinen viitekehys on Sosiologi Everett Rogersin malli innovaatioiden diffuusiosta. Taiteen kannattaminen uutena ideana vertautuu tutkielmassa uuteen keksintöön ja sen leviämiseen. Tutkielmassa osoitetaan, että kuvataiteen saadessa 1800-luvun kuluessa uudenlaisia merkityksiä myös taiteen yleisö määrittyi uudelleen. Vuonna 1846 perustetulla Suomen Taideyhdistyksellä oli tässä ratkaiseva ja aktiivinen rooli. Taiteen kannattajakunnan ydin oli Helsingissä, jossa vaikutti yhdistyksen lähinnä korkeista virkamiehistä ja professoreista koostunut johtokunta. Taideyhdistyksen toiminnan vakiintuessa taiteen kannattamisen idea levisi ja sitä levitettiin yhä useammille paikkakunnille sekä laajempiin kansankerroksiin. Yhdistyksen jäsenkuntaan liittyi lähinnä säätyläistöä, mutta taidenäyttelytoiminta tavoitti myös alempia yhteiskuntaluokkia. Taideyhdistyksen helsinkiläisessä jäsenkunnassa virkamiehistön rooli oli suuri. Alkuvaiheessa liittyneet yhteiskunnalliselta statukseltaan korkeat henkilöt saivat hallitsijan vakuuttumaan toiminnan luotettavuudesta. Taiteen kannattajakunta muodostui kuitenkin kasvavassa määrin alemmasta virkamiehistöstä ja elinkeinojen harjoittajista. Merkittävä osuus oli myös Keisarillisen Aleksanterinyliopiston opettajilla ja siellä tutkinnon suorittaneilla. Tärkein taiteen pääkaupunkilaista kannattajakuntaa yhdistänyt sosiaalinen viitekehys olikin yliopisto. Sen antama koulutus, sivistys ja henkinen pääoma olivat taustalla suurimmalla osalla yhdistykseen Helsingissä liittyneistä. He kuuluivat pääsääntöisesti aktivoituvaan sivistyneistöön, joka syntyi sääty-yhteiskunnan vanhojen rakenteiden hämärtyessä ja yliopistotutkintojen saadessa yhä suurempaa yhteiskunnallista merkitystä.

Faster Algorithms for Incremental Topological Ordering.Robert Tarjan

We present two online algorithms for maintaining a topological order of a directed acyclic graph as arcs are added, and detecting a cycle when one is created. Our first algorithm takes O(m 1/2) amortized time per arc and our second algorithm takes O(n 2.5/m) amortized time per arc, where n is the number of vertices and m is the total number of arcs. For sparse graphs, our O(m 1/2) bound improves the best previous bound by a factor of logn and is tight to within a constant factor for a natural class of algorithms that includes all the existing ones. Our main insight is that the two-way search method of previous algorithms does not require an ordered search, but can be more general, allowing us to avoid the use of heaps (priority queues). Instead, the deterministic version of our algorithm uses (approximate) median-finding; the randomized version of our algorithm uses uniform random sampling. For dense graphs, our O(n 2.5/m) bound improves the best previously published bound by a factor of n 1/4 and a recent bound obtained independently of our work by a factor of logn. Our main insight is that graph search is wasteful when the graph is dense and can be avoided by searching the topological order space instead. Our algorithms extend to the maintenance of strong components, in the same asymptotic time bounds.

Averting biodiversity collapse in tropical forest protected areas

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon(1-3). With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses(4-9). As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world's major tropical regions. Our analysis reveals great variation in reserve `health': about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.