scholarly journals Modeling of the Dark Phase of Flight and the Impact Area for Meteorites of Real Shapes

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Karol Havrila ◽  
Juraj Tóth ◽  
Leonard Kornoš
Keyword(s):  
The Body ◽  
Particle Orientation ◽  
Symmetric Body ◽  
Spherically Symmetric ◽  
The Real ◽  
Earth’S Atmosphere ◽  
Significant Difference ◽  
Impact Area ◽  
Earth's Atmosphere ◽  
The Impact

Aims. The complex dynamics of bodies, originating from the interplanetary matter and passing through Earth’s atmosphere, defines their further position, velocity, and final location on Earth’s surface in the form of meteorites. One of the important factors that affect the movement of a body in the atmosphere is its shape and orientation. Our goal is to model the interaction of real shape meteoroids with Earth’s atmosphere and compare the results with the standard spherical body approach. Methods. In the simulation, we use 3D models of fragments of the Košice meteorite with different sizes and shapes. Using a 3D model of fragments, we consider the real shape of the body to define its resistance properties during atmospheric transition more specifically. The simulation is performed using virtual wind tunnel in the MicroCFD (Computational Fluid Dynamics) software to obtain more realistic drag coefficients and using the µ(m)-Trajectory software to model the particle trajectory in the atmosphere including the wind profile. The final outputs from these programs are the drag coefficient as a function of the altitude and the particle orientation. Using these parameters we get the more realistic body trajectory and the impact area coordinates. Comparison of the results for real and spherical model meteorite impact location is discussed. Results. Simulation showed significant differences in trajectory and the impact area for the different real body orientations compared to the spherically symmetric body. Also, an important result is a difference in the impact area of the real body with a specific orientation without rotation and the body with considered rotation. The significant difference between the modeled impact of a real shape body and its real place of finding compared to a spherically symmetric body indicates the importance of the method used.

scholarly journals The Promise of Creativity

2012 ◽  
Vol 6 (1) ◽  
pp. 389-407 ◽  
Author(s):  
Maxine E. Sprague ◽  
Jim Parsons
Keyword(s):  
Real World ◽  
Teaching And Learning ◽  
The Body ◽  
The Real ◽  
Digital World ◽  
Body Of Knowledge ◽  
Imaginative Play ◽  
A Priority ◽  
The Impact

In this paper, the authors discuss creativity and the impact it might have on teaching and learning. The authors believe that imaginative play, at all ages, helps all people (children especially) create healthy environments and spaces that expand their learning. The authors contend that teaching for imagination—which asks little more than creating and trusting an ecological space that engenders it—seldom is considered a priority. Given the emphasis on creativity in the real world and the virtual digital world, the authors believe it is important to add to the body of knowledge through continued research in this field.

scholarly journals Effect of Siguan Acupuncture on Gastrointestinal Motility: A Randomized, Sham-Controlled, Crossover Trial

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Kyung-Min Shin ◽  
Ji-Eun Park ◽  
Sanghun Lee ◽  
Sun-Mi Choi ◽  
Yo-Chan Ahn ◽  
...  
Keyword(s):  
Gastrointestinal Motility ◽  
Acupuncture Treatment ◽  
Gastrointestinal Symptoms ◽  
Sham Acupuncture ◽  
The Body ◽  
Acupuncture Group ◽  
The Real ◽  
Real Acupuncture ◽  
Significant Difference ◽  
Sham Acupuncture Group

Siguan acupoints have been used to treat gastrointestinal symptoms in acupuncture practices for a long time. This study aimed to investigate the effects of Siguan acupuncture on gastrointestinal motility under accelerated conditions using a randomized, sham-acupuncture-controlled, crossover study. Twenty-one healthy male subjects were hospitalized and randomized into either a real acupuncture group (at Siguan acupoints) or a sham acupuncture group. Subjects were administered with mosapride citrate (15 mg a day) for 2 days starting 24 hours before the first acupuncture treatment. Immediately after the administration of radio markers, acupuncture treatment was conducted 4 times at 12-hour intervals. Gastrointestinal motility was assessed using radiograph distribution of the radio-markers located in the small intestine, ascending colon, transverse colon, descending colon, rectum, and outside the body immediately after the first acupuncture treatment and at 6, 12, 24, and 48 hours. After a 2-week washout period, the real acupuncture group in the first session was treated with sham acupuncture in the second session, and vice versa. Gastrointestinal motility was generally reduced in the real acupuncture group compared with the sham acupuncture group throughout the 4 different time points. A significant difference was observed at 24 hours following the first acupuncture treatment (P<0.05).

scholarly journals Effect of intermittent versus continuous calorie restriction on body weight and cardiometabolic risk markers in subjects with overweight or obesity and mild-to-moderate hypertriglyceridemia: a randomized trial

2020 ◽  
Vol 19 (1) ◽  
Author(s):  
Mahsa Maroofi ◽  
Javad Nasrollahzadeh
Keyword(s):  
Body Weight ◽  
Calorie Restriction ◽  
Density Lipoprotein ◽  
The Body ◽  
Trial Registration ◽  
Lipoprotein Cholesterol ◽  
Short Term ◽  
Significant Difference ◽  
The Impact ◽  
Overweight Or Obesity

Abstract Background Intermittent calorie restriction (ICR) is a novel method of dietary restriction for body weight control with the potential to improve obesity-related cardiometabolic markers, but the impact of this diet on subjects with hypertriglyceridemia (HTG) remains unknown. Methods Eighty-eight subjects with overweight or obesity and mild-to-moderate HTG were randomized to the continuous calorie restriction (CCR) group, or ICR group (a very low-calorie diet during 3 days of the week) for 8 weeks (44 patients in each group). Body composition, plasma lipids, glucose, insulin, adiponectin, and liver enzymes were measured at baseline and after 8 weeks. An intention-to-treat analysis was performed. Results The body weight decreased in both groups (4.07 ± 1.83 kg in the CCR group and 4.57 ± 2.21 kg in the ICR group) with no significant difference between the groups. There was no significant difference between the two groups in the reduced amount of fat mass, fat-free mass, and waist circumference. Both groups achieved a significant reduction in plasma triglycerides after 8 weeks (by 15.6 and 6.3% in ICR and CCR groups, respectively) with no difference between treatment groups. HOMA-IR improved significantly in ICR compared to the CCR group (P = 0.03). Plasma glucose, insulin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, liver enzyme, and adiponectin were not different between the two groups. Conclusions The results of this short-term study suggest that three-days a week of the ICR is comparable to a CCR diet for the reduction of triglycerides level in patients with HTG and in the short-term it appears to be more effective than continuous dieting in improving insulin resistance. However, longer-term studies are needed to confirm these findings. Trial registration Trial registration number:NCT04143971.

scholarly journals 262 Heat stress alleviation and dynamic temperature measurement for growing beef cattle

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 192-193
Author(s):  
Sheyenne M Augenstein ◽  
Meredith A Harrison ◽  
Sarah C Klopatek ◽  
James W Oltjen
Keyword(s):  
Heat Stress ◽  
Body Temperature ◽  
Beef Cattle ◽  
Ambient Temperature ◽  
The Body ◽  
Control Group ◽  
Temperature Threshold ◽  
Sprinkler Systems ◽  
Significant Difference ◽  
The Impact

Abstract Heat stress continues to be a challenge for feedlot producers, forcing physiological adaptations in beef cattle that can have a negative impact on gain and carcass quality. Feedlots may want to incorporate systems that aid in mitigating heat stress, including sprinkler systems, which are commonly found on dairies. The objective of this study was to determine the impact of sprinkler systems on the body temperature of growing feedlot steers applied at three different temperature thresholds. Thirty-two Angus-cross beef steers (298 ± 15 SD days of age) were randomly assigned to 8 pens. Treatments were assigned to pens according to location to avoid drainage issues, with one replicate located on the eastern side of the feedlot and the other replicate located on the western side. Treatments including no sprinklers (C), high temperature threshold sprinklers (HT), moderate temperature threshold sprinklers (MT) or low temperature threshold sprinklers (LT). Sprinklers (flow rate: 5.11 L/min) were activated at 33°C (HT), 28°C (MT), and 23°C (LT) for five minutes at corresponding temperatures every thirty minutes for 57 days. Rectal temperature of steers in their pens was measured in the morning (0800 h), afternoon (1500 h), and evening (1900 h) three days each week (Monday, Wednesday, Friday) for a total of 19 experimental days. Weather measurements, including ambient temperature, windspeed, humidity and solar radiation were recorded at each measurement time along with the maximum values for each day. The change in body temperature (ΔBT) between the morning and afternoon was affected by ambient temperature (P &lt; 0.01); MT (P = 0.02) and LT (P = 0.02) – different than C. There was no significant difference between sprinkler treatments and the control group (P &gt; 0.05). Day affected (ΔBT) between the morning and afternoon (P &lt; 0.05) and the afternoon and evening (P &lt; 0.05). When averaged by day, the control group was significantly higher than MT (P = 0.04) between the morning and afternoon. The control group was also significantly higher than LT between the morning and afternoon (P = 0.03) and the afternoon and evening (P &lt; 0.01). The change in steer body temperature between afternoon and morning was affected by ambient temperature, and averaged across days, lowering the temperature threshold for sprinkling decreased in the afternoon and evening body temperature increase in steers.

Predation pressure, density-induced stress and tail regeneration: a casual-nexus situation or a bunch of independent factors?

2009 ◽  
Vol 30 (4) ◽  
pp. 471-482 ◽  
Author(s):  
Gerasimia Tsasi ◽  
Efstratios Valakos ◽  
Chrysi Simou ◽  
Panayiotis Pafilis
Keyword(s):  
Negative Impact ◽  
Predation Pressure ◽  
The Body ◽  
Defensive Strategy ◽  
Tail Regeneration ◽  
Regeneration Rate ◽  
Island Populations ◽  
Induced Stress ◽  
Significant Difference ◽  
The Impact

AbstractCaudal autotomy, the self-induced tail shedding from the body, is a common defensive strategy in lizards. Tail loss is followed rapidly by regeneration, revealing the importance of a fully functional tail. Predation pressure has been traditionally correlated with autotomy performance. However there is a lack of evidence regarding the impact of predation regime on tail regeneration. Another important factor that has been neglected is the population density. Though it is well established that crowding alters various life-history traits, the impact of density on caudal regeneration remains understudied. In this paper we compared three island populations of the Aegean Wall Lizard (Podarcis erhardii) that have evolved under different levels of predation pressure: whereas the Naxos population is exposed to numerous predators the Kopries and Daskalio islet populations experience low predation pressure. To evaluate the effect of density-induced stress on caudal regeneration, lizards were treated under two conditions of housing, in single and crowded (six individuals) terraria. Tail sheding occurred prior to this treatment following a standardised method. The length of regenerated tail was recorded weekly. Regeneration rate was higher in single terraria when compared to crowded, reflecting the negative impact of crowding. However we failed to detect any statistically significant difference between single and crowded terraria in the case of Naxos. We believe that the underlying reason must be the heavy predation pressure under which rapid tail regeneration, even under unfavourable conditions, is crucial for survival. It seems that the imperious need for regeneration counteracts density-induced stress.

Effects of Ascogregarina culicis (Eugregarinorida: Lecudinidae) on Mosquito Size and Dengue Virus Infection in Aedes aegypti (Diptera: Culicidae)

2020 ◽  
Author(s):  
Panpim Thongsripong ◽  
Dawn M Wesson
Keyword(s):  
Virus Infection ◽  
Aedes Aegypti ◽  
Dengue Virus ◽  
Infection Rate ◽  
Wing Length ◽  
The Body ◽  
Global Public Health ◽  
Dengue Virus Infection ◽  
Significant Difference ◽  
The Impact

Abstract Dengue virus infection, transmitted via mosquito bites, poses a substantial risk to global public health. Studies suggest that the mosquito’s microbial community can profoundly influence vector-borne pathogen transmissions, including dengue virus. Ascogregarina culicis (Ross) of the phylum Apicomplexa is among the most common parasites of Aedes aegypti (Linnaeus), the principal vector of dengue. Despite a high prevalence worldwide, including in the areas where dengue is endemic, the impact of A. culicis on Ae. aegypti vector competence for dengue virus is unknown. This study aimed to investigate the effects of A. culicis infection on mosquito size and fitness, as measured by wing length, and the susceptibility to dengue virus infection in Ae. aegypti. Our results showed that there was no statistically significant difference in wing lengths between Ae. aegypti infected and not infected with A. culicis. Furthermore, A. culicis infection did not significantly affect dengue virus infection or disseminated infection rate. However, there was a significant association between shorter wings and higher dengue virus infection rate, whereby a 0.1-mm increase in wing length decreased the odds of the mosquito being infected by 32%. Thus, based on our result, A. culicis infection does not influence the body size and dengue virus infection in Ae. aegypti. This study helps to shed light on a common but neglected eukaryotic mosquito parasite.

scholarly journals Relationship between body weight and leptin concentrations in mink dams and the birth parameters of kits

2016 ◽  
Vol 72 (12) ◽  
pp. 755-759 ◽  
Author(s):  
Monika Bryl ◽  
Hanna Bis-Wencel ◽  
Brygida Ślaska ◽  
Bożena Nowakowicz-Dębek ◽  
Zbigniew Bełkot ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Condition ◽  
Scoring System ◽  
The Body ◽  
The Other ◽  
Blood Samples ◽  
Serum Leptin ◽  
Significant Difference ◽  
Analysis Of Results ◽  
The Impact

The aim of this study was to assess the impact of the leptin concentration and body weight of mink females on the birth parameters of their kits. Blood samples were collected 3 times during preparation for reproduction, 7±2 days before mating. Total leptin concentration in serum was measured using commercial RIA kits (Millipore, St. Charles, Missouri USA). Research was conducted on 20 clinically healthy scanbrown female minks (Neovison Vison) aged 2-3 years. To evaluate their body condition, the females were divided into two groups based on the BCS scoring system. In the first group, referred to as BCS 2, lean females were included, and the second group (BCS 4) consisted of obese females. In mink dams belonging to BCS 2, the average leptin values were one-fourth of those in the BCS 4 group. The results obtained indicate the influence of the body mass of minks during preparation for reproduction on serum leptin concentration. The results of the Mann-Whitney U test showed a statistically significant difference between weights and leptin concentrations in groups BCS 2 and BCS 4. Among the other traits, such differences were not found. The analysis of results obtained in the two mink groups did not reveal a clear relationship between leptin in the serum of mothers before mating and the birth parameters of their kits.

scholarly journals Mixed Reality Simulation of High-Endurance Unmanned Aerial Vehicle with Dual-Head Electromagnetic Propulsion Devices for Earth and Other Planetary Explorations

2020 ◽  
Vol 10 (11) ◽  
pp. 3736
Author(s):  
Ashish Kumar ◽  
Sugjoon Yoon ◽  
V.R.Sanal Kumar
Keyword(s):  
Mixed Reality ◽  
Walking Robots ◽  
Flight Simulator ◽  
The Real ◽  
Earth’S Atmosphere ◽  
Simulation Based ◽  
Aerial Vehicle ◽  
Earth's Atmosphere ◽  
New Generation ◽  
Electromagnetic Propulsion

One of the major limitations of existing unmanned aerial vehicles is limited flight endurance. In this study, we designed an innovative uninterrupted electromagnetic propulsion device for high-endurance missions of a quadcopter drone for the lucrative exploration of earth and other planets with atmospheres. As an airborne platform, this device could achieve scientific objectives better than state-of-the-art revolving spacecraft and walking robots, without any terrain limitation. We developed a mixed reality simulation based on a quadcopter drone and an X-Plane flight simulator. A computer with the X-Plane flight simulator represented the virtual part, and a real quadcopter operating within an airfield represented the real part. In the first phase of our study, we developed a connection interface between the X-Plane flight simulator and the quadcopter ground control station in MATLAB. The experimental results generated from the Earth’s atmosphere show that the flight data from the real and the virtual quadcopters are precise and very close to the prescribed target. The proof-of-concept of the mixed reality simulation of the quadcopter at the Earth atmosphere was verified and validated through several experimental flights of the F450 spider quadcopter with a Pixhawk flight controller with the restricted endurance at the airfield location of Hangang Drone Park in Seoul, South Korea. We concluded that the new generation drones integrated with lightweight electromagnetic propulsion devices are a viable option for achieving unrestricted flight endurance with improved payload capability for Earth and other planetary explorations with the aid of mixed reality simulation to meet the mission flight path demands. This study provides insight into mixed reality simulation aiming for Mars explorations and high-endurance missions in the Earth’s atmosphere with credibility using quadcopter drones regulated by dual-head electromagnetic propulsion devices.

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