Neurons in the monkey midbrain with activity related to vergence eye movement and accommodation

1986 ◽  
Vol 55 (5) ◽  
pp. 915-930 ◽  
Author(s):  
S. J. Judge ◽  
B. G. Cumming

We recorded from neurons dorsal and dorsolateral to the third nerve nucleus of the monkey whose discharge rates modulated when the monkey tracked targets moving in depth but not when it tracked targets moving from side to side. The neurons' activity modulated equally well whether the target moved directly toward one eye or the other. For most neurons the amplitude of modulation was similar whether the monkey tracked monocularly (blur cue alone), binocularly with accommodation open-loop (disparity cue alone), or in normal binocular viewing. By comparing the modulation in normal binocular viewing with that when the blur and disparity cues were in conflict we were able to show that 19 neurons discharged in relation to the vergence response alone and not to accommodation. Eight neurons discharged exclusively in relation to accommodation. While the monkeys tracked targets moving in depth so that target vergence varied with a sinusoidal time course (frequency 0.1 or 0.2 Hz) the discharge modulations of identified vergence cells generally showed much more phase lead than expected of motoneurons. We examined the activity of a subset of these vergence cells in response to a range of stimulus frequencies to compare the dynamics of these neurons with motoneurons. The phase leads were larger than those expected of motoneurons over the entire frequency range tested. We speculate that vergence neurons may selectively activate (directly or indirectly) motoneurons with longer time constants than the mean.

Author(s):  
Sahib Singh Chawla

The laminar boundary layer on a magnetized plate, when the magnetic field oscillates in magnitude about a constant non-zero mean, is analysed. For low-frequency fluctuations the solution is obtained by a series expansion in terms of a frequency parameter, while for high frequencies the flow pattern is of the ‘skin-wave’ type unaffected by the mean flow. In the low-frequency range, the phase lead and the amplitude of the skin-friction oscillations increase at first and then decrease to their respective ‘skin-wave’ values. On the other hand the phase angle of the surface current decreases from 90° to 45° and its amplitude increases with frequency.


2004 ◽  
Vol 14 (27) ◽  
pp. 83-88
Author(s):  
Elton Matsushima ◽  
Paula Chiaretti ◽  
Daniel Kreling ◽  
Murilo Lima ◽  
José Aparecido Da Silva ◽  
...  

Several studies using visually directed actions as indicators of perceived distance showed that people could accurately walk toward targets far up to 22m. Those results, summed up to those related to perceptual measures of perceived distance, showed that those responses were controlled by a single internal variable, namely visually perceived location. In the present study, we compared performance in bisection tasks, performed by open-loop walking or by perceptual matching. Observers (N=20) walked toward or adjust a pointer to the mean point of an egocentric distance (5, 10 or 15m), under binocular viewing. Results indicated accuracy on both responses, with no reliable differences between them, supporting the hypothesis of a single internal variable controlling action and perception. This invariant may be determined by a weighted set of sources of information.


1989 ◽  
Vol 121 (1) ◽  
pp. 109-115 ◽  
Author(s):  
J. A. Russell ◽  
R. E. Blackburn ◽  
G. Leng

ABSTRACT The region anterior and ventral to the third ventricle (AV3V) region is a major source of excitatory afferents to the magnocellular neuroendocrine system, and is essential for the osmotically regulated release of oxytocin. We investigated whether this input has a similarly essential role in parturition. Rats were implanted with a guide cannula in the AV3V region on days 9–18 of pregnancy. Following the birth of the third pup, rats were anaesthetized briefly with ether and either given an electrolytic AV3V lesion or a sham procedure was carried out. In eight AV3V-lesioned rats the mean (± s.e.m.) median interbirth interval following the lesion was 6·3 ± 1·2 min compared with 5·2 ± 0·6 min in 11 sham-lesioned rats. All rats completed delivery of their litters. The mean plasma concentration of oxytocin was unchanged following the sham procedure (pre-sham 17·1±2·8 pmol/l, n = 8; 15 min post-sham 18·1±2·7 pmol/l, n = 8; 30 min post-sham 19·2 ± 3·5 pmol/l, n = 8). In AV3V-lesioned rats, plasma oxytocin was significantly raised following the lesion (pre-lesion 14·6±1·3 pmol/l, n = 7; post-lesion 58·3 ± 9·8 pmol/l, n = 7) and was still higher than the sham-treated group after 30 min (55·8 ± 9·9 pmol/l). Thus there was no significant difference in the time-course of parturition between AV3V-lesioned rats and sham-lesioned rats, and no evidence that the lesion impaired the release of oxytocin. Furthermore, in rats given an AV3V lesion on the morning of the expected day of delivery, parturition was neither delayed nor disrupted, suggesting that the AV3V region does not contribute to the mechanisms controlling the onset of parturition. Journal of Endocrinology (1989) 121, 109–115


2015 ◽  
Vol 8 (2) ◽  
pp. 93
Author(s):  
Juniar Siregar

This study presents a research report on improving students’ Learning results on IPA through Video. The objective was to find out whether students’ learning result improved when they are taught by using Video. It was conducted using classroom action research method. The subject of the study was the Grade IV students of SDN 187/IV Kota Jambi which is located on Jln. Adi Sucipto RT 05 Kecamatan Jambi Selatan, and the number of the students were 21 persons. The instruments used were test. In analyzing the data, the mean of the students’ score for the on fisrt sycle was 65,4 (42,85%) and the mean on cycle two was 68,5 (37,15%) and the mean of the third cycle was 81,4 (100%). Then it can be concluded that the use of video on learning IPA can improve the students’ learning result. It is suggested that teachers should use video as one of the media to improve students’ learning result on IPA.Keywords : IPA, students’ learning result, video


1973 ◽  
Vol 72 (4) ◽  
pp. 753-761 ◽  
Author(s):  
Alberto Angeli ◽  
Giuseppe Boccuzzi ◽  
Roberto Frajria ◽  
Daniela Bisbocci ◽  
Franco Ceresa

ABSTRACT 10 mg/kg of dibutyryl cyclic adenosine 3′,5′-monophosphate (Db-cAMP) was iv pulse injected into twelve healthy adult women. The plasma cortisol levels were determined as 11-OHCS at zero time and then at 2.5, 5, 7.5, 10, 15, 30, 60 and 180 min after the injection. The data were compared with those obtained at the corresponding times in two groups of eleven and seventeen healthy women after the injection of 250 ng and 250 μg of synthetic β-1-24 corticotrophin performed in the same manner as the injection of the nucleotide. The mean increments in plasma cortisol were significantly lower after Db-cAMP than after ACTH. Differences were noted by analyzing the time course of the responses. In the case of stimulation with Db-cAMP the 11-OHCS levels rose progressively to a maximum at 15–30 min. By contrast, a peak of plasma cortisol was evident in most cases within a few min after the injection of ACTH; after a fall, a later rise was then observed starting from 15 min. The differences in the plasma 11-OHCS responses after the two stimuli may also be of interest clinically for the investigation of some aspects of adrenal steroidogenesis.


Author(s):  
Hotria Manik ◽  
Elia Masa Ginting

This study attempts to improve students’ writing achievement in recount text through Think-Pair-Share Strategy. This study was conducted by using classroom action research. The subject of the research was class VIII-1 SMPN 1 Pematangsiantar. The number of the students was 32 students, consisted of 5 males and twenty seven females. The research was conducted in two cycles and consisted of six meetings. The instruments for collecting data were writing tests as the quantitative data and diary notes, observation sheet, interview sheet and questionnaire sheet as qualitative data. Based on the writing score, students’ scores kept improving in every test. In analyzing the data, the mean of the students’ score for the first test as a pre-test was 57.84, for the second test as a post test I was 73.56, for the third test as a post test II was 77.56. Based on diary notes, observation sheet and questionnaire sheet, it was found that students were actively involved in writing process. The result of the research showed that Think-Pair-Share Strategy can improve students’ achievement in writing recount text.   Keywords: Think Pair Share, Writing, Recount text, Action research


Author(s):  
Esra N.F. Hutahaean And Tjut Ernidawati

This research concerns on improving students’ writing achievement in the report text through film.  The objective was to find out the improvement of students’ writing achievement in writing the report text through film. This research was conducted by using action research method. The subject of the research was XI IPA grade students of SMA SWASWTA JOSUA Medan. The numbers of students were thirty one students. They were taught writing the report text through film. The instruments used were writing report text test, diary notes, interview sheets, questionnaire sheets and observation sheets. In analyzing data, the mean of students’ score for the first competency test was 43.1, for the second competency test was 64.8 and for the third competency test was 76.3 and the total percentage of improvement from the first competency test to the third competency test was 84.1%. The conclusion is that through watching film can improve the students’ writing achievement in the report text. It is suggested that teachers should apply watching film as one of media to improve students’ writing achievement in the report text.


2013 ◽  
Vol 20 (3) ◽  
pp. 259-265
Author(s):  
Monica Vereş ◽  
Aurel Babeş ◽  
Szidonia Lacziko

Abstract Background and aims: Gestational diabetes represents a form of diabetes diagnosed during pregnancy that is not clearly overt diabetes. In the last trimester of gestation the growth of fetoplacental unit takes place, thus maternal hyperglycemia will determine an increased transplacental passage, hyperinsulinemia and fetal macrosomia. The aim of our study was that o analyzing the effect of maternal glycemia from the last trimester of pregnancy over fetal weight. Material and method: We run an observational study on a group of 46 pregnant women taken into evidence from the first trimester of pregnancy, separated in two groups according to blood glucose determined in the third trimester (before birth): group I normoglycemic and group II with hyperglycemia (>92mg/dl). Results: The mean value of third trimester glycemia for the entire group was of 87.13±22.03. The mean value of the glycemia determined in the third trimester of pregnancy was higher in the second group (109.17 mg/dl) in comparison to the first group (74.,21 mg/dl). The ROC curve for third trimester glycemia as fetal macrosomia appreciation test has an AUC of 0.517. Conclusions: Glycemia determined in the last trimester of pregnancy cannot be used alone as the predictive factor for fetal macrosomia.


Author(s):  
Eva C. Böckmann ◽  
E. S. Debus ◽  
R. T. Grundmann

Abstract Purpose The publication activity of 38 German general/visceral surgery university departments, documented by first or last authorship from staff surgeons (chief and consultants), was evaluated. Methods The observation period extended from 2007 to 2017 and all PubMed-listed publications were considered. Impact factor (IF) was evaluated through the publishing journal’s 5-year IF in 2016, as was the IF for each individual publication. Ranking was expressed in quartiles. Results The staff surgeons of the 38 departments comprised 442 surgeons, of which only 351 (79.4%) were active as first or last authors. Four thousand six hundred and ninety-nine publications published in 702 journals were recorded. The four leading departments in publication number published as much as the last 20 departments (1330 vs. 1336 publications, respectively). The mean of the first (most active) department quartile was 19.6 publications, the second 15.4, the third 11.0, and the last quartile 7.6 per publishing surgeon. The total cumulative impact factor was 14,130. When examining the mean number of publications per publishing surgeons per the 10 year period, the mean of the first quartile was 57.9 cumulative IF, the second 45.0, the third 29.5, and the fourth quartile 17.1. With 352 (7.5%) publications, the most frequently used journal was Chirurg, followed by Langenbeck’s Archives of Surgery with 274 (5.8%) publications. Pancreas-related topics led in terms of publication number and IF generated per individual publication. Conclusion A significant difference in publication performance of individual departments was apparent that cannot be explained by staff number. This indicates that there are as yet unknown factors responsible for minor publication activity in many university departments.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Li-Xia Zhang ◽  
Ning Dong ◽  
Rui-Xia Yang ◽  
Ang Li ◽  
Xuan-Mei Luo ◽  
...  

AbstractObjectivesGestational thrombocytopenia (GT) is the most common cause of thrombocytopenia during pregnancy. However, the occurrence and severity of thrombocytopenia throughout pregnancy in Chinese women are not fully defined.MethodsWe analyzed platelet counts in Chinese women who received prenatal care and/or delivered at the First Affiliated Hospital with Nanjing Medical University between January 2, 2018 and July 19, 2018 in China. These platelet counts were compared with those of nonpregnant women in the same study period.ResultsThe platelet counts of all women continued to decrease significantly each trimester (p < 0.0001). The mean platelet counts of the 818 women who had pregnancy-related complications were lower than those of the 796 women who had uncomplicated pregnancies during the third trimester (p = 0.047). At the time of delivery, platelet counts less than 150 × 109/L were more common in women with pregnancy-related complications than in women with uncomplicated pregnancy (26.7% vs. 19.7%, p = 0.03).ConclusionsPlatelet counts decrease throughout pregnancy in Chinese women and platelet counts less than 150 × 109/L were more common in women with pregnancy-related complications than in women with uncomplicated pregnancy. The pregnant women should be paid more attention for thrombocytopenia to avoid the occurrence of bleeding events.


Sign in / Sign up

Export Citation Format

Share Document