149 research outputs found
Perioperativ omvårdnad vid kejsarsnitt hos tik – förbättra utfall för tik och valpar
Dystocia, or difficult birth, is a commonly seen complication to natural birth in veterinary hospitals. Although other methods of resolving dystocia exist, 60 % of dystocias will need to undergo caesarean section. To perform a caesarean section, the bitch will have to undergo anesthesia.
The purpose of this literary study was to provide a deeper understanding regarding how the physiologic changes that occur during pregnancy influence anesthetic management in the bitch and puppies. Which anesthetic drugs and drug combinations indicated was also investigated as well as how a veterinary nurse can optimize care of the mother throughout the procedure and how resuscitation of the puppies should be carried out for best possible outcome.
This study, investigating concurrent literature on the subject, found that the bitch has an increased sensitivity to anesthetics subsequent to physiologic changes following pregnancy and have an increased sensitivity towards apnea and the hypoxia that follows. She is also more prone to regurgitation and aspiration due to physiologic changes in the GI-tract. Every drug administered to the bitch will cross the placenta and the same effect seen in the mother will be seen in the puppies.
Several anesthetic compounds was suggested for anesthesia in caesarean section in dogs, but protocols including acepromazine, alpha2-agonists and the combination ketamin-midazolam was found to be associated with increased puppy mortality and are hence not recommended. Analgesia was found to be a controversial subject in the concurrent literature.
Care to the mother must be taken throughout the procedure. The key points being that the mother should not be stressed and should be preoxygenated for 3-5 minutes prior to induction to prevent maternal and fetal hypoxia. The risk for regurgitation and aspiration should be minimized. Hypothermia must be prevented and the bitch should get proper pain relief before or during surgery to make her more comfortable postoperatively and allow the puppies to suckle soon after surgery.
Resuscitation of the puppies should focus on getting them warm, removing fetal membranes with towels and clear airways. Rubbing them dry vigorously, focusing on genital, umbilical and lumbar area will stimulate breathing and circulation. Intubation and ventilation may be required. Care must be taken so that drugs are not administered before circulation is sufficient
Directed Energy For Relativistic Propulsion and Interstellar Communications
An orbital planetary defense system that is also capable of beamed power propulsion allows mildly relativistic spacecraft speeds using existing technologies. While designed to heat the surface of potentially hazardous objects to the evaporation point to mitigate asteroid threats the system is inherently multi-functional with one mode being relativistic beamed spacecraft propulsion. The system is called DE-STAR for Directed Energy Solar Targeting of Asteroids and exploRation. DE-STAR is a proposed orbital platform that is a modular phased array of lasers, powered by the sun. Modular design allows for incremental development, test and initial deployment, lowering cost, minimizing risk and allowing for technological co-development, leading eventually to an orbiting structure that could be erected in stages. The main objective of DE-STAR would be to use the focused directed energy to raise the surface spot temperature of an asteroid to ~3,000 K, allowing direct evaporation of all known substances. The same system is also capable of propelling spacecraft to relativistic speeds, allowing rapid interplanetary travel and relativistic interstellar probes. Our baseline system is a DE-STAR 4, which is a 10 km square array that is capable of producing a 30 m diameter spot at a distance of 1 AU from the array. Such a system allows for engaging an asteroid that is beyond 1 AU from the DE-STAR 4. When used in its “photon rail gun mode”, a DE-STAR 4 would be capable of propelling a 1, 10, 102, 103, 104 kg spacecraft that is equipped with a 30 m diameter reflector to 1 AU in approximately 0.3, 1, 3, 10, 30 days, respectively, with speeds of about 4%, 1.2%, 0.4%, 0.15%, 0.05% the speed of light at 1 AU. With continued illumination to 3 AU the spacecraft, with a 30 m diameter reflector, would reach speeds √2 faster. A DE-STAR 4 could propel a 102 kg probe with 900 m diameter reflector to 2% the speed of light with continued illumination out to 30 AU, and ultimately to 3% the speed of light after which the spacecraft will coast. Such speeds far exceed the galactic escape velocity. Smaller systems are also extremely useful and can be built now. For example, a DE-STAR 1 (10 m size array) would be capable of evaporating space debris at 104 km (~diam. of Earth) while a DE-STAR 2 could divert volatile-laden asteroids 100 m in diameter by initiating engagement at ~0.01-0.5 AU. All sized systems can be used to propel varying sized systems for both testing and for interplanetary use. An extreme case is a wafe scale spacecraft (WaferSat) with a 1 m reflector that can achieve \u3e25%c in about 15 minutes. The phased array configuration is capable of creating multiple beams, so a single DE-STAR of sufficient size could engage several threats simultaneously or propelling several spacecraft. A DE-STAR could also provide power to ion propulsion systems, providing both a means of acceleration on the outbound leg, and deceleration for orbit insertion by rotating the spacecraft “ping-ponging” between two systems in either a photon rail gun mode or power ion engines. There are a number of other applications as well including SPS for down linking power to the Earth via millimeter or microwave. A larger system such as a DE-STAR 6 system could propel a 104 kg spacecraft to near the speed of light allowing for true interstellar travel. The same technology can also be used for extremely long range communications with continuous communication between Earth and the interstellar spacecraft. This technology also has direct implications for interstellar and intergalactic beaming allowing for SETI across the universe for civilizations that have mastered this technology. There are a number of other applications for the system. While decidedly futuristic in its outlook many of the core technologies now exist and small systems can be built to test the basic concepts as the technology improves. While there are enormous challenges to fully implementing this technology the opportunities enabled are truly revolutionary
Sexualitet - en del av äldreomsorgen?
The purpose of this study was to explore how nursing home managers relate to sexual needs of the elderly in the nursing homes. The empirical data consists of a vignette study followed by interviews with three nursing home managers. The aim was to involve six managers in our study but due to a major loss of respondents, we chose to complete our data collection with a review of the values which the elderly care is committed to follow by law. The major results of our empirical data suggest that sexual needs are not seen as an important issue in the daily care of the elderly. Even though the nursing home managers agreed on sexuality being an important need for the elderly, they only deal with the issue if the sexual need becomes a problem. Our results were analyzed with a perspective of new institutional organization theory. One conclusion from the analysis is that the nursing home managers way of relating to the sexual needs of the elderly, is closely linked to society norms and values surrounding their organizations. Our study also shows that the organizations are depending on legitimacy from the environment to maintain being entitled to needed society resources. To obtain this legitimacy, the nursing home managers are forced to meet the sexual needs of the elderly in accordance to how the environment expects them to work with elderly sexuality
Motivationen inom emotionen: Affekt, motivationell intensitet och dess verkan på uppmärksamhet
The purpose of the study was to investigate how attention is influenced by emotions with different Motivational Intensity (MI). Previous research found that it is the valence of an emotion that influences attention (broadens or narrows), but more recent studies have focused on Motivational Intensity (MI). In our study (n=81), we examined positive emotions with high MI, positive emotions with low MI, negative emotions with high MI and negative emotions with low MI, and neutral, which has never before been examined in the same study. We predicted that emotions with high MI would narrow the attentional scope whereas emotions with low MI would broaden the attentional scope, according to previous studies. The experiment consisted of pictures inducing different emotions and Navon’s letter task to assess attentional breadth. The result did not indicate significant interaction between affect and local vs. global attention. A possible explanation being discussed is that the pictures did not induce the affect strongly enough. Since there are only a few studies in this field, we believe that more research needs to be done with methods inducing affect more efficiently. Instead of using self-assessments, EMG could be a better and more sensitive option for the the manipulation check.Studien syftade till att undersöka hur uppmärksamheten påverkas av emotioner med olika motivationell intensitet. Tidigare forskning har visat att det är valensen hos emotionen som avgör om uppmärksamheten riktas mot delen eller helheten, men nyare studier har pekat på att det är den motivationella intensiteten (MI) som spelar en avgörande roll. I vår studie (n=81) undersöktes positiva emotioner med låg resp. hög MI, negativa emotioner med låg resp. hög MI samt neutrala emotioner, något som inte har studerats i en och samma studie tidigare. Vi förväntade oss, i linje med tidigare studier, att emotioner med hög motivationell intensitet skulle smalna av uppmärksamheten, alltså ge snabbare reaktionstid till lokala stimuli, medan emotioner med låg motivationell intensitet skulle bredda uppmärksamheten och bidra till snabbare reaktionstid för globala stimuli. Experimentet bestod av bilder för varje emotion (emotionsinduktion) samt ett uppmärksamhetstest (Navon’s test). Resultatet visade inte på signifikant interaktion mellan lokal och global uppmärksamhet och affekt. En möjlig förklaring är att bilderna inte inducerade affekterna tillräckligt effektivt, och vi anser därför att det behövs mer forskning med andra metoder som inducerar affekt på ett mer rättvisande sätt. Manipulationskontrollen skulle förslagsvis kunna utföras med hjälp av det mer sensitiva instrumentet EMG
Effect of aging on cerebral tissue oxygenation in relation to reflex syncope
Background: There is an increased susceptibility to syncope with aging attributed to age-related physiological impairments. Cerebral oxime-try non-invasively measures cerebral tissue oxygenation (SctO2) and has been shown to be valuable in syncope evaluation. SctO2 has beenfound to decrease with aging but it is unknown whether the decrease in SctO2 is related to increased susceptibility to syncope during ortho-static provocation. By measuring SctO2 during head up tilt test (HUT) we can study age-related differences in SctO2 and their impact ondeveloping reflex syncope.Purpose: To investigate the effect of age on the cerebral tissue oxygenation threshold for syncope and presyncope among patients withvasovagal syncope.Methods: Non-invasive haemodynamic monitoring and near-infrared spectroscopy (NIRS) were applied during head-up tilt (HUT) in 139vasovagal syncope patients (mean [SD] 45[17] years, 60% female), and 82 control patients with a normal response to HUT (45[18] years,61% female). Group differences in SctO2 and systolic blood pressure (SBP) during HUT in supine position, after 3 and 10 min of HUT, 30seconds prior to syncope ("presyncopal phase") and during syncope in different age groups (60 years) were comparedusing one-way ANOVA and Tukey"s multiple comparison test. Associations between age and SctO2 were studied using linear regressionmodels adjusted for sex and concurrent SBP.Results: Lower SctO2 in supine position was associated with increasing age among controls (B=-0.085, p = 0.010) but not among VVS pa-tients (B=-0.036, p = 0.114). No age-related differences in SctO2 were found after 3 and 10 minutes of HUT and during syncope. MeanSctO2 (%) during the presyncopal phase decreased over the advancing age groups (60: 62.2 ± 5.8; p = 0.009 for inter-group comparison). In contrast, mean SBP during the presyncopal phase did not differ by age groups (60: 77.6 ± 20.8 mmHg, p = 0.133). Age was associated with lower SctO2 during the presyncopal phase after adjusting for sexand SBP (B = 0.096, p = 0.001).Conclusion: Older VVS patients have lower cerebral tissue oxygenation in the presyncopal phase compared with younger patients inde-pendently of systolic blood pressure. These results suggest either that with imminent reflex syncope cerebral tissue oxygenation diminishesmore with advancing age or that cerebral deoxygenation is better tolerated by older reflex syncope patients
Simulations of Directed Energy Thrust on Rotating Asteroids
Asteroids that threaten Earth could be deflected from their orbits using directed energy to vaporize the surface, as the ejected plume creates a reaction thrust that alters the asteroid’s trajectory. In this situation, a critical issue is the rotation of the asteroid relative to the directed energy beam, as this will reduce the average thrust magnitude and modify the thrust direction. Flux levels required to evaporate surface material depend on the surface material composition, rotation rate, albedo, and thermal and bulk mechanical properties of the asteroid. The observed distribution of asteroid rotation rates is used, along with an estimated range of material and mechanical properties, as input to a 4D thermalphysical model to calculate the resultant thrust vector. The model uses a directed energy beam, striking the surface of a rotating sphere with specified material properties, beam profile, and rotation rate. The model calculates thermal changes in the sphere, including vaporization and mass ejection of the target material. The amount of vaporization integrated over the target is used to determine the thrust magnitude and the phase shift relative to the non-rotating case. As the object rotates beneath the beam, the energy spreads out, decreasing temperature and vaporization causing both a phase shift and magnitude decrease in the average thrust vector. This produces a 4D analytical model of the expected thrust profile for rotating objects
Directed Energy Active Illumination for Near-Earth Object Detection
On 15 February 2013, a previously unknown ~20 m asteroid struck Earth near Chelyabinsk, Russia, releasing kinetic energy equivalent to ~570 kt TNT. Detecting objects like the Chelyabinsk impactor that are orbiting near Earth is a difficult task, in part because such objects spend much of their own orbits in the direction of the Sun when viewed from Earth. Efforts aimed at protecting Earth from future impacts will rely heavily on continued discovery. Ground-based optical observatory networks and Earth-orbiting spacecraft with infrared sensors have dramatically increased the pace of discovery. Still, less than 5% of near-Earth objects (NEOs) 100 m/~100 Mt TNT have been identified, and the proportion of known objects decreases rapidly for smaller sizes. Low emissivity of some objects also makes detection by passive sensors difficult. A proposed orbiting laser phased array directed energy system could be used for active illumination of NEOs, enhancing discovery particularly for smaller and lower emissivity objects. Laser fiber amplifiers emit very narrow-band energy, simplifying detection. Results of simulated illumination scenarios are presented based on an orbiting emitter array with specified characteristics. Simulations indicate that return signals from small and low emissivity objects is strong enough to detect. The possibility for both directed and full sky blind surveys is discussed, and the resulting diameter and mass limits for objects in different observational scenarios. The ability to determine both position and speed of detected objects is also discussed
Directed Energy Deflection Laboratory Measurements
We report on laboratory studies of the effectiveness of directed energy planetary defense as a part of the DE-STAR (Directed Energy System for Targeting of Asteroids and exploRation) program. DE-STAR and DE-STARLITE are directed energy stand-off and stand-on programs, respectively. These systems consist of a modular array of kilowatt-class lasers powered by photovoltaics, and are capable of heating a spot on the surface of an asteroid to the point of vaporization. Mass ejection, as a plume of evaporated material, creates a reactionary thrust capable of diverting the asteroid’s orbit. In a series of papers, we have developed a theoretical basis and described numerical simulations for determining the thrust produced by material evaporating from the surface of an asteroid. In the DE-STAR concept, the asteroid itself is used as the deflection propellant . This study presents results of experiments designed to measure the thrust created by evaporation from a laser directed energy spot. We constructed a vacuum chamber to simulate space conditions, and installed a torsion balance that holds an asteroid sample. The sample is illuminated with a fiber array laser with flux levels up to 60 MW/m2 which allows us to simulate a mission level flux but on a small scale. We use a separate laser as well as a position sensitive centroid detector to readout the angular motion of the torsion balance and can thus determine the thrust. We compare the measured thrust to the models. Our theoretical models indicate a coupling coefficient well in excess of 100 μN/W optical, though we assume a more conservative value of 80 μN/W optical and then degrade this with an optical encircled energy efficiency of 0.75 to 60 μN/W optical in our deflection modeling. Our measurements discussed here yield about 45 μN/W absorbed as a reasonable lower limit to the thrust per optical watt absorbed
Optical Modeling for a Laser Phased-Array Directed Energy System
We present results of optical simulations for a laser phased array directed energy system. The laser array consists of individual optical elements in a square or hexagonal array. In a multi-element array, the far-field beam pattern depends on both mechanical pointing stability and on phase relationships between individual elements. The simulation incorporates realistic pointing and phase errors. Pointing error components include systematic offsets to simulate manufacturing and assembly variations. Pointing also includes time-varying errors that simulate structural vibrations, informed from random vibration analysis of the mechanical design. Phase errors include systematic offsets, and time-varying errors due to both mechanical vibration and temperature variation in the fibers. The optical simulation is used to determine beam pattern and pointing jitter over a range of composite error inputs. Results are also presented for a 1 m aperture array with 10 kW total power, designed as a stand-off system on a dedicated asteroid diversion/capture mission that seeks to evaporate the surface of the target at a distance of beyond 10 km. Phase stability across the array of λ/10 is shown to provide beam control that is sufficient to vaporize the surface of a target at 10 km. The model is also a useful tool for characterizing performance for phase controller design in relation to beam formation and pointing
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