Identification of the Gene Encoding the Tryptophan Synthase β-Subunit from Chlamydomonas reinhardtii1

We report the isolation of a Chlamydomonas reinhardtii cDNA that encodes the β-subunit of tryptophan synthase (TSB). This cDNA was cloned by functional complementation of a trp-operon-deleted strain of Escherichia coli. Hybridization analysis indicated that the gene exists in a single copy. The predicted amino acid sequence showed the greatest identity to TSB polypeptides from other photosynthetic organisms. With the goal of identifying mutations in the gene encoding this enzyme, we isolated 11 recessive and 1 dominant single-gene mutation that conferred resistance to 5-fluoroindole. These mutations fell into three complementation groups, MAA2, MAA7, and TAR1. In vitro assays showed that mutations at each of these loci affected TSB activity. Restriction fragment-length polymorphism analysis suggested that MAA7 encodes TSB. MAA2 and TAR1 may act to regulate the activity of MAA7 or its protein product.

Concepciones sobre las tecnologías de la información y la comunicación (TIC) y sus implicaciones educativas: un estudio exploratorio con profesorado de la provincia de Ñuble, Chile

El propósito de este estudio fue conocer las concepciones de profesores de educación primaria sobre las tecnologías educativas en dos dimensiones: a) conocimiento de las tecnologías de la información y comunicación; y b) creencias sobre el uso educativo que el profesorado da a estas herramientas. Se opta por un enfoque metodológico cuantitativo y un diseño no-experimental descriptivo del tipo encuesta. El análisis de los datos se realizó mediante paquete estadístico SPSS 14.0 y las técnicas utilizadas fueron descriptivos, frecuencias y porcentajes, técnicas de reducción de datos (análisis factorial) e inferencia estadística (comparación de medias y porcentajes). Los resultados demuestran que la mayoría de los profesores reconocen el interés que las tecnologías despiertan en el alumnado y las oportunidades de aprendizaje que ofrecen principalmente en relación con los diferentes ritmos de aprendizaje y las necesidades educativas especiales. Se identifica la b��squeda de información como una competencia fundamental, así como se evidencia que existe una relación causal entre el nivel de formación, la importancia que el profesor otorga al recurso y el uso educativo. Los resultados hacen aconsejable promover programas de formación continua en esta área y fortalecer la formación inicial docente.

The Account of Thomas B. Gannett Executor of the last will & testament of Caleb Gannett late of Cambridge Esqr. deceased, 1819 February

Four-page handwritten account statement of the estate of Caleb Gannett with the note on the verso: "This account of administration was rendered the Judge, but was declared by him to be incorrect-- Feb 1819."

Letters from Benjamin Welles to John Henry Tudor, 1799-1801

Benjamin Welles wrote these six letters to his friend and classmate, John Henry Tudor, between 1799 and 1801. Four of the letters are dated, and the dates of the other two can be deduced from their contents. Welles wrote Tudor four times in September 1799, at the onset of their senior year at Harvard, in an attempt to clear up hurt feelings and false rumors that he believed had caused a chill in their friendship. The cause of the rift is never fully explained, though Welles alludes to "a viper" and "villainous hypocrite" who apparently spread rumors and fueled discord between the two friends. In one letter, Welles asserts that "College is a rascal's Elysium - or the feeling man's hell." In another he writes: "College, Tudor, is a furnace to the phlegmatic, & a Greenland to thee feeling man; it has an atmosphere which breathes contagion to the soul [...] Villains fatten here. College is the embryo of hell." Whatever their discord, the wounds were apparently eventually healed; in a letter written June 26, 1800, Welles writes to ask Tudor about his impending speech at Commencement exercises. In an October 29, 1801 letter, Welles writes to Tudor in Philadelphia (where he appears to have traveled in attempts to recover his failing health) and expresses strong wishes for his friend's recovery and return to Boston. This letter also contains news of their classmate Washington Allston's meeting with painters Henry Fuseli and Benjamin West.

Account book of Andrew Croswell, 1794-1802

Andrew Croswell kept this account book while an undergraduate at Harvard College. It contains entries from 1794, the year he entered, until his graduation in 1798. There is also one entry on the back cover apparently made in 1802. The entries, divided by school term, are very detailed. Croswell indicates the cost of the following, among many other expenses and purchases: transportation, most often to Hingham and Plymouth; payment for "passing the bridge"; candles; hiring a horse; wood and having it cut; laundry; quills and pencils; paper and ink; razors, haircuts, hair ribbons; a trunk; clothing and cloth for trousers; furniture; tickets to the theater; door locks; a bowl and spoon; "batts and balls" and "other necessaries"; tobacco; toothbrushes; shoe and boot repair; fruit; wine, brandy and rum; cheese; coffee and tea; butter; lemons; sugar; and wafers. There are also entries for college-related costs, including the payment of quarter bills, buttery bills, Hasty Pudding Club dues, and a fee to the President of Harvard College related to Croswell's graduation. There are also entries pertaining to the cost of celebrating various special occasions, including Election Day, Christmas Eve, "Independent Day," and George Washington's birthday.

Kitāb Tuḥfat ahl al-futūḥāt wa-al-adhwāq fī ittikhādh al-sub���ah wa-jaʻlihā fī al-aʻnāq wa-baʻḍ al-ādāb al-lāʼiqah bi-al-mukarramīn bi-ṣuḥbat ahl ḥaḍrat al-iṭlāq bi-faḍl al-karīm al-khallāq

lil-Shaykh Fatḥ Allāh ibn al-Shaykh Sayyidī Ab�� Bakr al-Bannānī.

Kitāb al-tarīqah al-wāḍiḥah ilá al-bayyinah al-rājiḥah

tartīb Maḥmūd ibn Ḥamzah.

Kitāb al-Fatāwá al-naẓm

li-Maḥmūd Afandī al-Ḥamzāwī.

Hādhā kitāb Qiṣaṣ al-ʻulamāʼ

min taʼlīfāt al-ʻālim al-fāḍil al-kāmil nukhbat al-ʻulamāʼ wa-al-mujtahidīn al-Mīrzā Muḥammad ibn Sulaymān al-Tunukābunī.

Hādhā kitāb al-Farāʼid al-raḍwīyah

min taʼlīfāt Mīrzā Muḥammad ibn Sulaymān al-Tunukābunī.

Janāb-i Ba-davlatnī hikāyātlārī : manuscript, 1904 or 5

An eyewitness account of Yaqub Beg's rule in parts of Xinjiang.