A Description and Experimental Analysis of a Stereotyped Cheliped Flexion Behaviour in Hermit Crabs

Behaviour ◽  
1977 ◽  
Vol 61 (3-4) ◽  
pp. 147-179 ◽  
Author(s):  
Laurence H. Field

AbstractSpontaneous cheliped flexion behaviour of hermit crabs was studied using a large aquarium with a gravel substrate. The effects of chemical, visual and tactile stimuli, as well as intervals between flexions were determined using a smaller tank, which facilitated experimentation. The behaviour consists of bringing the tip of the cheliped to the mouth by flexing the four most distal joints, opening the dactyl, wiping the claw with the third maxillipeds and re-extending. Single flexions are used in feeding to pick-up substrate particles covered with diatoms. The rate of activity increases in the presence of glycine (10-3M) or fish juice. Trains of flexions comprise a cleaning behaviour which is elicited by fouling of the claw with food or petroleum jelly, or by strong concentrations of chemicals (10-1M glycine or sea water of pH<1.5 or >9.5). In addition, cleaning flexion behaviour was elicited by a variety of disturbance stimuli, including sudden shadow, reflections from a mirror, vibration, "simulated attack" by a plastic rod, handling, and fighting with conspecific hermit crabs. The implications of this response as a displacement behaviour are discussed. The mean interval between cleaning flexions does not change significantly as glycine concentration is increased from 10-4M to 10-2M, but the mean rate of flexion increases sevenfold and mean adaptation time increases threefold. The mean inter-flexion intervals for the chelipeds of individual animals are not significantly different, but the small cheliped undergoes an average of 1.61 times more flexions than the large one.

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


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.


2018 ◽  
Vol 3 (2) ◽  
pp. 38-47
Author(s):  
Muhammad Abdul Azis ◽  
Nuryake Fajaryati

This research aims to create a Reosquido desalination tool for evaporation methods using a microcontroller. This tool can control the temperature to speed up the evaporation process in producing fresh water. The method applied to Reosquido desalination uses Evaporation. The first process before evaporation is the detection of temperature in sea water that will be heated using an element heater. The second process of temperature measurement is to turn off and turn on the Arduino Uno controlled heater, when the temperature is less than 80 ° then the heater is on. The third process is evaporation during temperatures between 80 ° to 100 °, evaporation water sticks to the glass roof which is designed by pyramid. Evaporated water that flows into the reservoir is detected by its solubility TDS value. The fourth process is heater off when the temperature is more than 100 °. Based on the results of the testing, the desalination process using a microcontroller controlled heater can speed up the time up to 55% of the previous desalination process tool, namely manual desalination prsoes without using the heater element controlled by the temperature and controlled by a microcontroller which takes 9 hours. Produces fresh water as much as 30ml from 3000ml of sea water, so that it can be compared to 1: 100.


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.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Ali Pouryousef ◽  
Erfan Eslami ◽  
Sepehr Shahriarirad ◽  
Sina Zoghi ◽  
Mehdi Emami ◽  
...  

Abstract Objectives The current study aimed to evaluate the effects of Ficus carica latex on the treatment of cutaneous leishmaniasis (CL), induced by Leishmania major. A 5% topical gel with F. carica latex was prepared. BALB/c mice were infected by inoculation of amastigotes form of L. major. Thirty BALB/c mice were divided into five groups, where the first group was treated daily, the second group twice per day, and the third group every other day with the 5% topical gel, for 3 weeks. The sizes of the lesions were measured before and during the course of treatment. Results Although the mean size of lesions in the mice group treated with the 5% F. carica gel, especially in the group receiving daily treatment, was less than the mean size of the lesions in the control group, yet, the differences was not statistically significant (p > 0.05). The findings of the current study demonstrated that the 5% F. carica latex with a 3-week course of treatment had no considerable effect in recovery or control of CL induced by L. major in the murine model. Using higher concentration of F. carica latex and with longer treatment lengths may increase its efficacy in the treatment of CL.


Genetics ◽  
1986 ◽  
Vol 113 (4) ◽  
pp. 1077-1091
Author(s):  
John H Gillespie

ABSTRACT A statistical analysis of DNA sequences from four nuclear loci and five mitochondrial loci from different orders of mammals is described. A major aim of the study is to describe the variation in the rate of molecular evolution of proteins and DNA. A measure of rate variability is the statistic R, the ratio of the variance in the number of substitutions to the mean number. For proteins, R is found to be in the range 0.16 &lt; R &lt; 35.55, thus extending in both directions the values seen in previous studies. An analysis of codons shows that there is a highly significant excess of double substitutions in the first and second positions, but not in the second and third or first and third positions. The analysis of the dynamics of nucleotide evolution showed that the ergodic Markov chain models that are the basis of most published formulas for correcting for multiple substitutions are incompatible with the data. A bootstrap procedure was used to show that the evolution of the individual nucleotides, even the third positions, show the same variation in rates as seen in the proteins. It is argued that protein and silent DNA evolution are uncoupled, with the evolution at both levels showing patterns that are better explained by the action of natural selection than by neutrality. This conclusion is based primarily on a comparison of the nuclear and mitochondrial results.


1988 ◽  
Vol 119 (1) ◽  
pp. 111-116 ◽  
Author(s):  
G. J. King ◽  
R. Rajamahendran

ABSTRACT Plasma progesterone concentrations were compared in cyclic (n = 12), pregnant (n =12), oestradiol-induced pseudopregnant (n=12) and hysterectomized gilts (n=10) between days 8 and 27 after oestrus. The results were grouped into periods covering days 8–13, 14–20 and 21–27 and analysed by least-squares analysis of variance. Plasma progesterone concentrations were significantly (P<0·001) higher in hysterectomized compared with other groups between days 8 and 13. Progesterone concentrations declined rapidly after day 14 in cyclic females and gradually in the other groups. Throughout the third and fourth weeks the mean progesterone concentrations for hysterectomized animals were consistently higher than for pseudopregnant animals (P<0·05). The pregnant group means were below but not significantly different from the hysterectomized means in both of the last two periods. The greater progesterone concentrations in hysterectomized gilts indicated that secretion is high without any conceptus-produced or -mediated luteotrophin, and corpora lutea in cyclic, pregnant or pseudopregnant gilts may never reach full secretory potential. J. Endocr. (1988) 119, 111–116


Sign in / Sign up

Export Citation Format

Share Document