Aid Of Telescope Research Articles

Laparoscopic intrauterine artificial insemination and ultrasonic pregnancy diagnosis in Arabi ewes

Laparoscopic intrauterine artificial insemination (LAI) refers to a special technique by which the operation is done through several small holes in the abdomen with the aid of telescope. These incisions are much smaller than wound required in traditional surgery. This study aimed to evaluate the efficacy of laparoscopic artificial insemination. To increase the pregnancy and twins rate by using gonadotrophic releasing hormone (GNRH) and accurate pregnancy diagnosis in ewes by using ultrasonography, the present study was carried out in the animal farm college of veterinary medicine/Basrah University. Thisstudy started in 3rd August 2009 to 12th February 2010. This study included 9 ewes aged about 8 to 10 months and 2 rams aged between (9 to 11 months) and one of them was vasectomized. The rams were kept and separated from ewes for 2 weeks; at the beginning all ewes were checked for previous pregnancy by using of laparoscope. Injection of 0.00421 mg Buserelin hormone was given to induce estrus. The estrus ewes were prepared for surgical operations and made sedation by injection of Xylazine 0.11 to 0.22 mg/kg body weight (BW); and then 1 ml/cm2 of 2% of lidocaine was injected as local anesthesia. The animal was fixed on surgical table and then prepared for aseptic technique; afterwhich the ewes were inseminated laparoscopically by intra uterine injection of 0.25 ml of fresh ram semen. The results show the possibility of laparoscope as a technique used for artificial insemination in ewes in 71.4% of pregnancy rate. The laparoscopic insemination was successfully done in ewes without complication; there was no critical effect of intra-abdominal pressure (14 mmHg) by CO2 in small ruminants and pregnancy rate in ewes was successfully diagnosed by ultrasonography. Key words: Laparoscopic surgery, artificial insemination, ultra sonic, estrus, pregnant diagnos.

The development of the Ocutech VES-autofocus telescope and a future binocular version.

Conventional optical low-vision devices are hampered by the physical constraints of magnification-shallow depth of field and narrow field of view, and for telescopes, the need to change focus for different distances. These characteristics make low-vision telescopic aids difficult to use, especially at important midrange distances. The Ocutech VES Autofocus bioptic telescope (VES-AF) funded with National Institutes of Health-Small Business Innovation Research and Ontario (Canada) Ministry of Health grants, eliminates the need to manipulate the device to maintain focus. Clinical experience with the VES-AF has shown that autofocus (AF) enhances the acceptance and utilization of telescopic devices. Difficulty ignoring the fellow eye while sighting through the device has been a complaint of users that has undermined device acceptance. Although occlusion is an option to alleviate the diplopia experienced, the development of a binocular version may further enhance the acceptance, adaptation to, and utilization of telescopic devices and may offer wider fields of view as well.

The low vision distance telescope‐‐how useful an aid?

It is axiomatic that success in the use of any low vision aid depends largely upon the user's qualities of adaptability and skill. Distance telescopic aids, in particular, produce images with characteristics that are especially demanding of these qualities. Although patients appear largely content to accept their distance telescopes, a survey of individual successes and failures has not been reported. In the low vision service at University Hospital, Nottingham, 2695 patients were examined over a nine year period (January 1987–December 1995). Of these, 142 patients (5.3%) were supplied with distance telescopes. This sample consisted of 83 males and 59 females. The age range was between 9–91 years. A total of 9 patients had returned their telescopes because they no longer needed them. The remaining 133 patients were mailed a pilot questionnaire, aimed at evaluating their use of the telescope. Respondents to this were mailed a second, more detailed questionnaire, designed to examine in greater detail the individual's use of the appliance, their satisfaction with its performance etc. A total of 74/133 patients (56%) returned detailed questionnaires completed with quantifiable information. Statistical analysis showed: 1. Patients who found the telescopes easiest to use tended to use them most frequently 2. Monocularity tended to become commoner with age But, adaptability and skill did not appear significantly compromised by: 3. Increasing age 4. Monocularity/binocularity status. Fuller details of the results of this survey will be given in the poster.

The low vision distance telescope—how useful an aid?

It is axiomatic that success in the use of any low vision aid depends largely upon the user's qualities of adaptability and skill. Distance telescopic aids, in particular, produce images with characteristics that are especially demanding of these qualities. Although patients appear largely content to accept their distance telescopes, a survey of individual successes and failures has not been reported. In the low vision service at University Hospital, Nottingham, 2695 patients were examined over a nine year period (January 1987–December 1995). Of these, 142 patients (5.3%) were supplied with distance telescopes. This sample consisted of 83 males and 59 females. The age range was between 9–91 years. A total of 9 patients had returned their telescopes because they no longer needed them. The remaining 133 patients were mailed a pilot questionnaire, aimed at evaluating their use of the telescope. Respondents to this were mailed a second, more detailed questionnaire, designed to examine in greater detail the individual's use of the appliance, their satisfaction with its performance etc. A total of 74/133 patients (56%) returned detailed questionnaires completed with quantifiable information. Statistical analysis showed: 1. Patients who found the telescopes easiest to use tended to use them most frequently 2. Monocularity tended to become commoner with age But, adaptability and skill did not appear significantly compromised by: 3. Increasing age 4. Monocularity/binocularity status. Fuller details of the results of this survey will be given in the poster.

Suboptimal vision after vitreous surgery in diabetics.

Between 1979-1985, 105 diabetic patients underwent vitreous surgery for diabetic eye disease in one or both eyes. By spring 1991, 40 patients (38%) had died, and 36 (55%) of the living 65 patients had good or moderate vision (visual acuity, VA > or = 0.3 in the better eye), 13 (20%) had low vision (VA 0.05-0.25), and 16 (25%) were blind (VA < 0.05). For 19 of the 65 patients (29%) impaired vision was the main factor that limited independent activities. Of the 29 patients with suboptimal vision, 2 were employed, and none needed institutional care. Nine (31%) participated in all household activities, and 14 (48%) were able to read. Near vision aids were used by 14 of the 19 patients (74%) with ambulatory vision (VA > or = CF), but only 2 of them (11%) had accepted telescopic aids. Eight patients (28%) had a guide dog. In spite of vitreoretinal surgery, almost half of diabetic patients may end up with suboptimal vision, emphasizing the need for active visual rehabilitation.

Use of Telescopic Aids for Vocational Purposes

The importance of preparing visually impaired people for employment is well known. Equally important is the need for the feeling of comfort on the job. Low vision telescopic aids facilitate a variety of adaptations that can comfortably increase the productivity of the individual with low vision. They may also require specialized training.

Contrast sensitivity in albinotic patients.

Vertical and horizontal grating contrast sensitivity functions (CSF) were measured on eight albinotic patients. Several of these patients also had CSF measurements performed through their telescopic aids. For all the patients, the horizontal grating CSF was more sensitive than the vertical grafting CSF. Although there are many pathological problems that could result in this sensitivity difference (high astigmatism, neural modification, etc.), we propose that in this case, the nystagmoid eye movements are the main causative factor. Through the telescopic aid, the CSF resolution acuity and peak sensitivity increased. The increase in resolution was somewhat less than would be predicted based on magnification. The increase in sensitivity is believed to be the result of stimulation of more sensitive peripheral retina. This increase in sensitivity is an added benefit to these patients corrected with low vision aids.

The Night Sky in April

THE moon is full on April 11 at 21h. and new on April 26 at 13h. U.T. A naked-eye star, o Leonis (mag. 3·8) is occulted on April 7, the disappearance, as seen from Greenwich, taking place at 21h. 43·5m. at position angle 58° from the north point of the moon's image. Jupiter and its companion, Saturn, are planets of the evening sky. Both will soon be too close to the sun for observation, but they will re-emerge as morning stars towards the end of June. Mars continues as a morning star, and is 5° above the eastern horizon about 3h. 30m. U.T. in mid-April. The distant planet, Neptune, is not far from β Virginis and comes to the southern meridian shortly after 22h. U.T. in mid-April (add 1 h. to convert to Summer Time). This planet, seen as a star of magnitude 8, requires for its detection some telescopic aid and a section of a star map for guidance such as is given in the “Handbook of the British Astronomical Association, 1941”, p. 9. In the same constellation is one of the best-known binary stars, γ Virginis. The components are of nearly equal magnitude (3·6 and 3·7 respectively) and their present separation is 5¾″ the period is about 180 years. The Lyrid meteors are most frequent about April 20, their radiant point being near 104 Herculis, that is, south-preceding the bright star, Vega.

Occultations of Mars and Venus

IF the evening sky is clear on July 17, an interesting observation can be made without a telescope (though, preferably, slight optical aid is desirable) of the occultation of the planet Mars by the moon. The disappearance of Mars, as seen from a station near Greenwich, takes place at the moon's dark limb (the age of the moon being 9·7 days) at position angle 53 ° from the north point of the disk, measured eastwards, at 21h 13m U.T. (22h 13m Summer Time). The reappearance of Mars at the moon's bright limb is at position angle 326 ° at 22h 10m U.T. or 23h 10m Summer Time. The apparent diameter of Mars is about 14" and its stellar magnitude – 0·8. A map in the B.A.A. Handbook for 1937 gives the limits on the earth's surface of the visibility of this occultation. The occultation of Venus by the moon on August 3 takes place in full daylight and cannot, in any event, be seen from southern England. The southern limit of visibility of partial occultation, as given in J. Brit. Ast. Assoc., March, p. 187, runs approximately between Hull, Bradford and a little north of Blackpool ; the southern limit of total occultation runs from just south of Bridlington, to Borough Bridge and just north of Carnforth. At Edinburgh, the disappearance of Venus is due at 8h 26m U.T. at position angle 159 ° from the north point of the moon's disk, and the reappearance at position angle 212 ° at 9h lm (add lh to convert to Summer Time). The phenomenon will require telescopic aid generally, though Venus can on occasions be 'picked up' in daylight by keen-sighted observers. The moon's age is 26·2 days, so that the crescent is a very narrow one. Venus is in its gibbous phase, the ratio of the illuminated area of the disk to that of the entire apparent disk (17"in diameter) being 0·67. Its stellar magnitude is – 3·6. The position of Venus on August 3 at 9h is R.A. 5h 53m·0; Dec. + 21 ° 20'.

The Night Sky in November

AT the beginning of the month, the duration of night (defined, as the interval from sunset to the following sunrise) is 14 4 hours, and at the end of the month 15-3 hours in the latitude of London. The moon is new on November 14d 4.11 and full on November 28d 16.2h U.T. Occupations of stars brighter than magnitude 5 occur on November 28.29, when x Tauri reappears at 17h 30.6, “and T Tauri disappears at 23h 48 14m and reappears at lh 0.2m. The planet Venus sets this month in the early evening, and at sunset is low in the south-west. Jupiter is in the same region of the sky, and on the evening of November 12 will be found about 2° above Venus. The near approach of these two bright objects factual conjunction takes place on November 13d 12h) will be well worth looking for at nightfall on November 12 and following with telescopic aid about midday on November 13. Mars is a morning star of magnitude about + 1.8. Saturn is above the horizon during the first part of the night; on November 15 it sets just before 1h. Watch may be kept on November 15–16 for a possible display of the Leonid meteors. This shower, the radiant point of which is at R.A. 10h Om, Elec 4.22°, is generally visible every November, but at epochs of every 33 years it yields, with some exceptions, an unusually brilliant display. The last great shower was due in 1932, but in Great Britain it failed to come up to expectations, though at one station in the United States as many as 240 meteors were observed in an hour. November 19-20 is the date of maximum of the Andromedids, a shower associated with the lost comet of Biela; the radiant of the shower is not far from the star y Andromedæ. (Near v Andromedæ may be seen, with the naked eye, a tiny, faint hazy patch which is the Andromeda nebula, distant 870,000 light years.) The light variations of Algol (P Persei) can be observed at about the following times: November 8d 2h, 10d 23h, 13d 19h, 28d 4h and December 1d 0h. 1m mid-November at about 22h, the constellations Cassiopeia, Perseus, Andromeda, Aries and Cetus are on or near the meridian, but the eastern half of the sky, rich in first magnitude stars and led by the Pleiades, will probably claim the observer's attention.

Astronomical Topics

Sunspot Activity during 1931.—In the annual report of the Council to the Royal Astronomical Society, a summary is included of the sunspot activity for 1931. The average daily area of sunspots measured at Greenwich was approximately 260 millionths of the sun's hemisphere. This value for 1931 is half that for 1930, and the average daily number of spots showed a decrease in about the same ratio. On about forty days during 1931 no spots were seen on the sun's disc. Large groups of spots were, however, by no means entirely absent, and the following dates are the times of central meridian passage of groups of spots of 500 millionths or larger, that is, of the order of size at which a spot is visible near the centre of the disc without telescopic aid: Jan. 12.5, Feb. 20.6, Feb. 20.7, March 15.4, May 20.5,Nov. 26.9. The largest of these groups, with central meridian passage on Feb. 20.7 and in latitude 6° north, had a maximum area of nearly 1900 millionths. A note on this group was given in NATURE, 127, 321; 1931.

PLANETARY PHENOMENA FOR MAY AND JUNE, 1923

Mercury is in good position for evening observation during the first half of May. On May 1 it does not set until one and three-quarter hours after sunset, and this interval remains larger than one hour until after the middle of the month. Greatest east elongation is reached on May 5. It is not a very large one, only 21. °7, but the planet is 8° north of the Sun, and its time of setting is considerably retarded on that account. Shortly after the middle of May the apparent distance between Sun and planet is so reduced that it can no longer be seen without telescopic aid, and inferior conjunction is reached on May 28. The planet now becomes a morning star, and will continue so until it reaches superior conjunction late in July. Greatest west elongation is reached on June 22. The apparent distance from planet to Sun is then 22°33', which is about the average for greatest elongations. During the last half of June Mercury will rise about an hour before sunrise, and may be seen if weather conditions are favorable. On June 21 Mercury is in conjunction with Venus, the latter planet being 2° 38' north. There will be another and much closer conjunction on July 4, but the planets will then be much closer to the Sun and not in good position for naked eye observation. Venus is still a morning star, rising about an hour and a quarter before sunrise. This interval remains practically constant during the two months' period ; in fact, it is only three minutes shorter at the end than it is at the beginning, although the apparent distance from planet to Sun diminishes from 32° to 21°. But the planet is also 14° south of the Sun on May 1,

The Aurora of March 22–23

I HAD a fine view of this superb display at Workington between midnight and 1 o'clock a.m., in a clear and bright starlit sky. The whole sky was filled with the light except a small area in the south-east. I could detect no colour except creamy-white, the general intensity being, to my mind, at times equal to full moonlight. Curtains of light surrounded a point just east of the zenith, which seemed to mark the “hub” of the display. The bright star (a) in Canes Venatici almost exactly marked this point, and filmy sheets of light seemed to dash upwards from the south-west and north-east horizons and merge together at this star. The only display I have ever seen to equal this was on 1907 February 14 at Motherwell, in the previous sun-spot maximum period. It was the fact that I could see the great sun-spot train on March 22 without telescopic aid that made me expect and look out for the aurora that night.

Our Astronomical Column

OLBERS' COMET OF 1815.—On March 6, 1815, Olbers discovered a small comte at Bremen, in about 49°. right ascension, and 32° north declination, or between Perseus and Musca; it had an ill-defined nucleus and was not visible without telescopic aid. The first parabolic elements were calculated by Olbers himself, and he was followed by Bessel, Gauss, Triesnecker and others in the determination of similar orbits. Ephemerides founded upon them showed that the comet would be observable for a considerable period, and as the result proved observers were not negligent of this circumstance. Gauss, writing to Bode on April 24, alludes to the long visibility of the comet, and the probability that elliptical elements would be found, but this remark apparently was merely intended to imply that the grasp which a long course of observation would afford upon the orbit, might lead to an ellipse, not that Gauss had remarked any sensible deviation from parabolic motion; indeed he mentions that he had not then reduced his April observations. The first detection of the inadequacy of the parabola to represent accurately the comet's course, is due to Bessel: he had calculated parabolic elements from observations on March 11, April 11, and May 20, which, while agreeing well with the positions employed, gave the right ascensions sensibly too small from March 11 to April 11, and between April 11 and May 20, as decidedly too great, even to as much as 4′, and on May 26, the calculation was again many minutes in defect; these differences naturally induced Bessel to relinquish the parabolic hypothesis, and after some disappointment from the failure of the first method he employed, he communicated to Olbers on June 23 the elements of an elliptical orbit, in which the period of revolution was a little over 73 years. At the end of June Gauss deduced an ellipse with a period of 77 years, and soon afterwards Nicolai, then assistant to von Lindenau at Gotha, added a further confirmation of the elliptical character of the orbit, assigning a revolution of 721/2 years. On July 22, being in possession of observations to the middle of the month, Bessel improved upon his first calculation, and now found an ellipse with a period of 73.8968 years, which was made the foundation for his subsequent investigations, of which we have presently to speak. Thus was the periodicity of the comet established, and Bessel, after remarking upon the importance of the addition to the system (at that time Halley's comet was the only one that could be considered certainly periodical) he proposed that it should bear the name of its discoverer— Olbers.

Societies and Academies

Societies and Academies

Meteorology of the Future

IT is with some satisfaction that I have read in NATURE of December 12, 1872, the very interesting paper of Mr. J. Norman Lockyer, entitled “Meteorology of the Future,” giving adhesion and the support of his name to the discovery of Mr. C Meldrum of a cycle and the support of his name to the discovery of Mr. C Meldrum, of a cycle of 11 years in the recurrence of the maximum of cyclones and rainfall in the southern hemisphere; a cycle corresponding with that already recognized in the maximum of sun-spots. But I have been somewhat surprised to see that my name has not been mentioned by Mr. Lockyer in reference to Mr. Meldrum's paper, as I hive also published a paper on the connee ion of gun-spots with rainfalls, storms, C) clones, &c, prior to the first paper of Mr. Meldram, which appeared in NATURE, October 24, 1872. Thinking that my paper has escaped your notice, and trusting that you might have some interest to see it, I take the liberty to forward it to you with this same mail. It was published in the Boston Daily Advertiser, November 2, 1871. Over a year has elapsed since its publication, and few are the days on which I had no opportunity of seeing the sun and scrutinising its spots with especial care, with the aid of telescope and spectroscope; and to-day I do not see the necessity of changing a word of the conclusions which I had come to in that paper. Only it appears that, in addition to the laws which I have drawn out, the position of the moon will have to be taken in consideration as a complicating element; as it seems that the conjunction and opposition have a tendency to increase the influence of the spots on our atmosphere, while the quadrature diminishes it in a certain measure. I could make some other remarks taken from my greater experience on the subject, but they are of secondary importance, and I will wait for another opportunity to publish them.