Sex determination in mythology and history

The history of ideas on how the sexes became divided spans at least three thousand years. The biblical account of the origin of Eve, and the opinions of the philosophers of classical Greece, have unexpected bearings on present-day ideas. The scientific study of sex determination can be said to have begun in the 17th century with the discovery of spermatozoa, but the origin and function of the “spermatic animalcules” eluded investigators until 1841. The mammalian egg was discovered in 1827, and in the last quarter of the century fertilization was observed. The view current at that time, that sex determination was under environmental control, gave way to the idea of chromosomal determination in the first quarter of the 20th century. The study of human and other mammalian chromosomes during the third quarter of the century, and the discovery of sex-chromosome abnormalities, emphasized the importance of the Y chromosome for male sex determination. The last quarter of the century witnessed a hunt for the “testis-determining” gene, thought to be responsible for the differentiation of Sertoli cells, and culminating in the isolation of SRY (Sry in the mouse). However, an increasing number of additional genes and growth factors were found to be required for the establishment of male sex. During the same period evidence emerged that male development was accompanied by enhanced growth, both of gonads and whole embryos. An unexpected finding was the demonstration of temperature-dependent sex determination in reptiles. With the advent of the 21st century, it was shown that Sry induces cell proliferation in fetal mouse gonads, and it has been suggested that male sex differentiation in mammals requires a higher metabolic rate. These insights could lead to a better understanding and improved treatment of abnormalities of sexual development

Sex determination and sexual differentiation

In humans and other mammals, sex is determined by the presence or absence of Y chromosome. If Y chromosome is present, it will channel the genital ridge of the embryo into the pathway of testis development, while in the absence of Y chromosome ovaries develop. Once testes have formed, they secrete anti-Müllerian hormone and testosterone, which masculinize the reproductive tract. By contrast, the female reproductive tract develops in the absence of fetal gonadal hormones. Testis development is brought about through the action of the sex determining region located on the short arm of the Y chromosome (Sry gene), but correct doses of other genes on autosomes as well as the X chromosome, are also required. Sry appears to be widely expressed in human fetuses, suggesting the possibility that its influence on development is not confined to the testes. There is additional evidence of a difference in developmental rates between XY and XX cleaving embryos, in which Sry and another gene in the sex-determining region named Zfy, for the zinc finger protein it encodes, are already expressed. These findings are consistent with the possibility that Y-chromosomal genes affect somatic sex differences prior to the formation of steroid hormones.Biomedical Reviews 1997; 7: 75-83

Science of languages : (Englisch-Französische Sprach- und Conversationslehre für alle Stände)

https://www.ester.ee/record=b4001843*es

The documents in the first book of the Maccabees and the foreign policy of the Maccabees

This thesis is a re-examination of the documents in 1 Maccabees, which have been the subject of much previous comment. Section 1 is a survey of previous work followed by a discussion of methods. Section 2 deals with the historic background and Section 3 contains detailed commentaries on the texts of the documents. The conclusion is arrived at that, except for the letter of Jonathan to the Spartans, the documents are genuine, and that, when allowance is made for Hebraisms they conform to the pattern of Hellenistic documents. The Seleucid documents provide valuable information on the status of Judaea under Seleucid rule and the issues in the conflict between the Maccabees and the Seleucids. The Roman letters are shown to be designed partly to support the Maccabees1 aspirations for independence, partly to consolidate their rule among the Jewish communities of the Diaspora. The Spartan letter is of minor importance. The decree in honour of Simon illustrates the nature of the new Maccabean High Priesthood. Taken together, the letters serve as a valuable guide to the policy, especially the foreign policy of the Maccabees.<p

Numeral Modifiers and Temporal Container Adverbials

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Optional and obligatory verbal complements in English.

This thesis investigates the factors that determine whether complements marked in the subcategorization of verbs are obligatory or optional. The model used is that of Chomsky (1965). In 1.1, the notion of verbal complement is defined and is limited to direct objects, indirect objects, prepositional objects, directionals and some locatives; 1.2, consists largely of a resume of past discussions that have a bearing on the main topic of this investigation. It emerges that a distinction must be drawn between the absence of unspecified and specified complements. Chapter 2 deals with the omission of unspecified complements, 3 with the omission of specified complements that consist of simple noun phrases. Chapter 4 opens with a discussion of the status of sentential complements and the structure of sentences containing such complements; the rest of the chapter deals with the omission of the various types of sentential complements. Chapter 5 deals with the omission of reflexive and reciprocal pronouns. Chapter 6 discusses how the phenomena described in Chapters 2--5 should be handled by a grammar. The conclusion is reached that verbs that can be used without specified complements should be subcategorized as taking optional complements, so that there is no need to account for the absence of unspecified complements by a deletion transformation. Such a transformation is, however, necessary to account for the absence of specified complements. The main body of the thesis is followed by three Appendixes

The sex difference in dimensional communalities in Macaca nemestrina

Intra-individual correlations for cranial, mandibular and dental measurements made on lateral skull radiographs of Macaca nemestrina were systematically higher in 30 adult females than in 31 adult males by an average of 0.11 to 0.15, depending upon method of computation. Clearly, for the adult pig-tailed monkey as in Homo during both prenatal and postnatal life, developmental and dimensional communalities are systematically higher in the female indicating a general principle or trend.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37552/1/1330430104_ftp.pd

Low Digit Ratio Predicts Early Age at Menarche in Colombian Schoolgirls

Background:  The ratio between the lengths of the second and fourth fingers (digit ratio: 2D : 4D), a purported negative correlate of prenatal androgen exposure, has been inversely related to age at menarche. However, a recent study found high digit ratios in carriers of a single variant in the LIN28B gene, which has been linked to delayed menarche. Methods:  We investigated the association of digit ratio and age at menarche in 299 pre‐menarcheal girls aged 5–12 years who participated in a longitudinal cohort study in Bogotá, Colombia. Finger lengths were measured at baseline and the occurrence of menarche was periodically ascertained over a median 32 months of follow‐up. We used time‐to‐event analysis to estimate median ages at menarche as well as hazard ratios for menarche according to tertiles of the digit ratio for each hand. Results:  Estimated median age at menarche was lower for girls in the lowest digit ratio tertile of the right hand compared with those in the highest (12.0 vs. 12.3 years; P ‐value = 0.04). After adjustment for baseline age, height‐ and body mass index‐for‐age z ‐scores, the hazard of menarche was 86% higher in girls of the lowest digit ratio tertile (hazard ratio 1.9 [95% confidence interval 1.2, 2.9]) compared with those in the highest digit ratio tertile of the right hand. No significant associations were found with the left hand. Conclusions:  Digit ratio was positively associated with age at menarche in this longitudinal investigation, consistent with results from a recent gene‐linkage study.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93549/1/j.1365-3016.2012.01310.x.pd