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1.
BackgroundVestibular patients occasionally report aggravation or triggering of their symptoms by visual stimuli, which is called visual vestibular mismatch (VVM). These patients therefore experience discomfort, disorientation, dizziness and postural unsteadiness.ObjectiveFirstly, we aimed to get a better insight in the underlying mechanism of VVM by examining perceptual and postural symptoms. Secondly, we wanted to investigate whether roll-motion is a necessary trait to evoke these symptoms or whether a complex but stationary visual pattern equally provokes them.MethodsNine VVM patients and healthy matched control group were examined by exposing both groups to a stationary stimulus as well as an optokinetic stimulus rotating around the naso-occipital axis for a prolonged period of time. Subjective visual vertical (SVV) measurements, posturography and relevant questionnaires were assessed.ResultsNo significant differences between both groups were found for SVV measurements. Patients always swayed more and reported more symptoms than healthy controls. Prolonged exposure to roll-motion caused in patients and controls an increase in postural sway and symptoms. However, only VVM patients reported significantly more symptoms after prolonged exposure to the optokinetic stimulus compared to scores after exposure to a stationary stimulus.ConclusionsVVM patients differ from healthy controls in postural and subjective symptoms and motion is a crucial factor in provoking these symptoms. A possible explanation could be a central visual-vestibular integration deficit, which has implications for diagnostics and clinical rehabilitation purposes. Future research should focus on the underlying central mechanism of VVM and the effectiveness of optokinetic stimulation in resolving it.  相似文献   

2.

In assessing the likely demand for biotechnology products it is not sufficient just to look at what is happening in firms and their immediate market environment. There is no one 'market' for biotechnology products: there are differences between sectors and between countries. You have instead to look at the institutional contexts of the biotechnology product's development. This paper reviews work which has been carried out by social scientists, especially those using 'social shaping' approaches, on the development of new products based on advances in biotechnology and on the creation of markets to go with these products. It examines work on public attitudes to the exploitation of the technology, focusing especially on the issue of social inclusion and exclusion and how biotechnology might make exclusion more likely. It concludes by considering what current differences in public attitudes to the development of some biotechnology-based products might mean for the development of markets for those products in the UK.  相似文献   

3.
African Fractals     

This article examines the visual essay as a special verbal/visual mode of expression that is practised both by social scientists and social documentarians, although still on a very limited scale. Examining some of their commonalities and differences sheds light on the particularities of the scientific versus the social documentary approach more generally. To conclude, a photo‐essay from a social documentary photographer is discussed, as it comes close to what could be termed a sociological approach. This borderline application allows elaboration of some of the specifics of the visual essay as a mode of visual anthropology/sociology.  相似文献   

4.
BackgroundInnovative physical activity monitoring technology can be used to depict rich visual feedback that encompasses the various aspects of physical activity known to be important for health. However, it is unknown whether patients who are at risk of chronic disease would understand such sophisticated personalised feedback or whether they would find it useful and motivating. The purpose of the present study was to determine whether technology-enabled multidimensional physical activity graphics and visualisations are comprehensible and usable for patients at risk of chronic disease.MethodWe developed several iterations of graphics depicting minute-by-minute activity patterns and integrated physical activity health targets. Subsequently, patients at moderate/high risk of chronic disease (n=29) and healthcare practitioners (n=15) from South West England underwent full 7-days activity monitoring followed by individual semi-structured interviews in which they were asked to comment on their own personalised visual feedback Framework analysis was used to gauge their interpretation and of personalised feedback, graphics and visualisations.ResultsWe identified two main components focussing on (a) the interpretation of feedback designs and data and (b) the impact of personalised visual physical activity feedback on facilitation of health behaviour change. Participants demonstrated a clear ability to understand the sophisticated personal information plus an enhanced physical activity knowledge. They reported that receiving multidimensional feedback was motivating and could be usefully applied to facilitate their efforts in becoming more physically active.ConclusionMultidimensional physical activity feedback can be made comprehensible, informative and motivational by using appropriate graphics and visualisations. There is an opportunity to exploit the full potential created by technological innovation and provide sophisticated personalised physical activity feedback as an adjunct to support behaviour change.  相似文献   

5.
Abstract

I was invited to this Workshop, because I have published papers on the mechanisms of action of small molecule fluorescent probes used with living cells. The Workshop provided an opportunity to interact with some significant figures in the chemosensor and bioimaging field from across the planet; to spend time with a large, friendly and active group of local investigators and their graduate students; and to take a brief look at a vibrant modern city. Many scientific connections were made and collaborations planned for the Biological Stain Commission and for my own future work.  相似文献   

6.
ABSTRACT

Nineteenth-century anthropologists struggled to establish themselves as scientists in a cultural milieu of enthusiasm for “curiosities.” Because commercial photographers appropriated the “authenticity” of photographic realism, the need increased for ethnographic photographers to distinguish between such realism and the “scientific authority” of their own visual productions. Through a case study of anthropometric photography of the Chippewa, this article examines the tension between, on the one hand, ethnographers' exploitation of the technological and symbolic attributes of photography to promote the scientific and political goals of the discipline, and on the other hand, the influence and function of visual genres and visual allegories in conditioning and framing what viewers accepted as “real” and “true.”  相似文献   

7.
ABSTRACT

Stomatopod crustaceans have highly mobile, independently moving compound eyes that are sensitive to both linearly and circularly polarized light. They rotate their eyes to predictable angles when viewing a linearly polarized target, and they scan their eyes frequently to sample the visual field. Angles of scans are roughly perpendicular to the plane of the midband (a set of specialized parallel rows of equatorial ommatidia). We investigated scanning eye movements in one Caribbean stomatopod species (Neogonodactylus oerstedii) in uniform visual fields that were vertically polarized, horizontally polarized, or depolarized. We found that mean eye rotation and scan angles differed significantly among these different treatments. Average scan angles differed by 12°, being more horizontal in a vertically polarized field than in a horizontally polarized one, and also more horizontal in a vertically polarized field than in a depolarized field. Thus, these stomatopods adjusted visual scanning to the polarization of the visual environment.  相似文献   

8.
PurposeThe current study evaluated the effect of lens-induced high myopia (IHM) on the activity of the occipital visual cortex during two visual stimuli presentations to the subjects. This was done by measuring the Blood Oxygenation Level Dependent (BOLD) signal using functional MRI (fMRI).MethodsBOLD contrast fMRI was performed with a 1.5T MRI scanner on 12 emmetropic subjects (refractive error <±0.25Diopter) with no history of neurologic disorder. IHM conditions were applied to subjects by three convex lenses of +5D, +7D and +10D. Visual stimuli with 0.34 cpd and 1.84 cpd spatial frequencies (SF) were presented as a block paradigm to the participants in three IHM states and normal vision state during fMRI data acquisition. Resultant fMRI data were compared among different refractive states.ResultsData analysis showed that IHM did not cause a significant change in the visual cortex activity throughout the presentation of 0.34 cpd SF visual stimulus and BOLD signal intensity remained approximately constant (p = 0.17). Although, fMRI responses to visual stimuli with spatial frequency of 1.84 cpd demonstrated that visual cortex activity was significantly reduced in IHM states compared to normal vision (p = 0.01), the results showed no significant differences between three different values of IHM.ConclusionsThis study shows severe blurring caused by lens induced high myopia can decrease BOLD signal intensity depending on the visual stimulus pattern details. However in the low and moderate range of spatial frequencies, blur increment from +5D up to +10D is not associated with further reduction in the BOLD signal of the occipital visual cortex.  相似文献   

9.
BackgroundTheranostics, a fusion of two key parts of modern medicine - diagnostics and therapy of the organism's disorders, promises to bring the efficacy of medical treatment to a fundamentally new level and to become the basis of personalized medicine. Extrapolating today's progress in the field of smart materials to the long-run prospect, we can imagine future intelligent agents capable of performing complex analysis of different physiological factors inside the living organism and implementing a built-in program thereby triggering a series of therapeutic actions. These agents, by analogy with their macroscopic counterparts, can be called nanorobots. It is quite obscure what these devices are going to look like but they will be more or less based on today's achievements in nanobiotechnology.Scope of ReviewThe present Review is an attempt to systematize highly diverse nanomaterials, which may potentially serve as modules for theranostic nanorobotics, e.g., nanomotors, sensing units, and payload carriers.Major ConclusionsBiocomputing-based sensing, externally actuated or chemically “fueled” autonomous movement, swarm inter-agent communication behavior are just a few inspiring examples that nanobiotechnology can offer today for construction of truly intelligent drug delivery systems.General SignificanceThe progress of smart nanomaterials toward fully autonomous drug delivery nanorobots is an exciting prospect for disease treatment. Synergistic combination of the available approaches and their further development may produce intelligent drugs of unmatched functionality.  相似文献   

10.
11.
IntroductionHomonymous visual field defects (HVFD) are a common consequence of postchiasmatic acquired brain injury and often lead to mobility-related difficulties. Different types of compensatory scanning training have been developed, aimed at decreasing consequences of the HVFD by changing visual scanning.AimThe aim of the present study is to examine the effects of a compensatory scanning training program using horizontal scanning on mobility-related activities and participation in daily life.MethodThe main interest of this study is to assess the effectiveness of training on mobility-related activities and participation in daily life. Visual scanning tests, such as dot counting and visual search, and control measures for visual functions and reading have been included as well. First, it is examined how performance on scanning and mobility-related measures is affected in patients with HVFD by comparing scores with scores of a healthy control group (n = 25). Second, the effect of training is assessed using an RCT design, in which performance of 26 patients before and after training is compared to performance of 23 patients in a waiting list control group.ResultsSelf-reported improvements after training were found, accompanied by improvements in detecting peripheral stimuli and avoiding obstacles during walking, especially in dual task situations in which a second task limits the attentional capacity available for compensatory scanning. Training only improved mobility-related activities in which detection of peripheral stimuli is important, while no improvement was found on tests that require other visual skills, such as reading, visual counting and visual search.ConclusionThis is the first RCT to evaluate the effects of a compensatory scanning training that is based on a systematic horizontal scanning rhythm. This training improved mobility-related activities. The results suggest that different types of compensatory scanning strategies are appropriate for different types of activities.

Trial Registration

ISRCTN Registry ISRCTN16833414  相似文献   

12.
Capsule Home-range of resident pairs of Golden Eagle was usually smaller during a successful breeding season than during winter and during an unsuccessful breeding season.

Aims To examine how Golden Eagles use space around their nests with respect to season and breeding status, and to compare home-range-use between a high and a low density region.

Methods Nine adults in six mainland Argyll ranges were radiotracked between 1991 and 1996. On the island of Mull visual observations of range-use were obtained for five ranges between 1994 and 1998.

Results Overall, Mull ranges were smaller than the Argyll ranges, reflecting the much higher range density on Mull. In both regions there were significant differences between ranging distances with season and breeding status. In general, ranging distances were smallest during breeding seasons when young were fledged.

Conclusions Studies of range-use in Golden Eagles must be conducted across a 12-month period, as a minimum.  相似文献   

13.
PurposeTo propose a new tablet-enabled test for evaluation of visual performance in glaucoma, the PERformance CEntered Portable Test (PERCEPT), and to evaluate its ability to predict history of falls and motor vehicle crashes.DesignCross-sectional study.MethodsThe study involved 71 patients with glaucomatous visual field defects on standard automated perimetry (SAP) and 59 control subjects. The PERCEPT was based on the concept of increasing visual task difficulty to improve detection of central visual field losses in glaucoma patients. Subjects had to perform a foveal 8-alternative-forced-choice orientation discrimination task, while detecting a simultaneously presented peripheral stimulus within a limited presentation time. Subjects also underwent testing with the Useful Field of View (UFOV) divided attention test. The ability to predict history of motor vehicle crashes and falls was investigated by odds ratios and incident-rate ratios, respectively.ResultsWhen adjusted for age, only the PERCEPT processing speed parameter showed significantly larger values in glaucoma compared to controls (difference: 243ms; P<0.001). PERCEPT results had a stronger association with history of motor vehicle crashes and falls than UFOV. Each 1 standard deviation increase in PERCEPT processing speed was associated with an odds ratio of 2.69 (P = 0.003) for predicting history of motor vehicle crashes and with an incident-rate ratio of 1.95 (P = 0.003) for predicting history of falls.ConclusionA portable platform for testing visual function was able to detect functional deficits in glaucoma, and its results were significantly associated with history of involvement in motor vehicle crashes and history of falls.  相似文献   

14.
Abstract

After the birth of Dolly, media stories on cloning were replete with references to well-known science fiction plots. This essay criticizes the ‘imagination deficit’ of scientists and journalists, first by problematizing the uncritical adoption of attenuated science fiction plots in the media coverage of Dolly, and second, by proposing to look at more expansive science fiction novels that carefully examine issues such as uniqueness and identity in relation to the new genetics.  相似文献   

15.
目的 当动物重复某种行为以逃避危险或获取奖励而无法成功时,会产生放弃。放弃是一种常见且基本的行为,在小鼠等模式动物中已经被广泛研究,但是其部分神经机制仍未被阐明。幼年斑马鱼适合进行全脑光学成像,是神经科学领域的重要模式生物。已经有研究者通过持续电击等消极刺激诱发斑马鱼放弃行为,然而奖励刺激能否引起斑马鱼放弃尚无报道。本文对奖励刺激引起的斑马鱼放弃行为进行了探究。方法 通过给予斑马鱼虚拟的食物视觉刺激,检验斑马鱼对虚拟食物的捕食情况,比较斑马鱼捕食频率和单次捕食时长随时间的变化。结果 虚拟的食物视觉刺激可以引起斑马鱼的捕食行为,接受25 min虚拟刺激后,8日龄以上斑马鱼的捕食频率和单次捕食时长均出现显著下降。结论 此研究丰富了斑马鱼放弃行为的研究范式,实验结果表明,缺失真实奖励的虚拟食物刺激可以诱导斑马鱼放弃捕食行为,这将进一步加深对动物放弃行为的理解,推动对其神经机制的研究。  相似文献   

16.
BackgroundCandida albicans chorioretinitis is the most common cause of endogenous fungal endophthalmitis. Echinocandins are recommended as first-line therapy in the treatment of invasive candidiasis (IC), but in clinically stable patients with IC and endophthalmitis caused by Candida species susceptible to azole compounds these are the first-line treatment due to their better intraocular penetration.Case reportA 42-year-old woman admitted to hospital for duodenal perforation after gastrointestinal surgery and treated with broad-spectrum antibiotics developed C. albicans candidemia. According to protocol, an antifungal treatment with anidulafungin was given. The patient presented no visual symptoms but on routinary ophthalmoscopic examination multiple bilateral chorioretinal lesions were observed. Systemic therapy was changed to fluconazole, with good systemic and ocular results.ConclusionsAzole compounds are the first-line therapy for endophthalmitis associated with candidemia. However, clinical guidelines often propose echinocandins as the first option for IC. In some cases, C. albicans chorioretinitis will require a change in the systemic treatment to assure better intraocular penetration. According to the current evidence and our own experience, routine funduscopy is not necessary in all IC patients. However, we do recommend fundus examination in patients with visual symptoms or those unable to report them (paediatric patients and patients with an altered level of consciousness), and in those who are being treated with echinocandins in monotherapy.  相似文献   

17.
《Endocrine practice》2023,29(1):48-52
ObjectiveThis study aims to assess patients’ knowledge and identify barriers in interpreting calcium on supplement and nutrition labels and to determine whether education would be beneficial.MethodsPatients with conditions requiring calcium supplementation were included in this study. Participants were first given a 9-question pre-education survey. They were then taught how to read calcium on labels using the educational cards developed. This was followed by a 7-question posteducation survey. Endocrinologists were surveyed to assess their experience in treating patients who required calcium supplementation.ResultsBefore education, 31 (33%) and 37 (40%) of the participants felt that the supplement and nutrition labels, respectively, were confusing. After education, only 2 (2%) and 6 (6%) of the participants, respectively, still felt the same. There was a significant improvement in the interpretation of calcium citrate (Citracal) and calcium carbonate (TUMS) labels, with a trend of improvement in reading a milk label. Of the 47 endocrinologists surveyed, only 5 (11%) felt that their patients often or always knew the correct amount of calcium to be taken. Two-thirds 30 (64%) of the endocrinologists always or often explained to their patients how to interpret calcium labels. About half 23 (49%) of the endocrinologists always or often needed to take time to look up the calcium content of supplements. For most endocrinologists 29 (62%), this took at least 2 to 4 minutes.ConclusionOur patients had trouble interpreting calcium labels, and the use of educational cards was effective in improving calcium literacy.  相似文献   

18.
目的:探究前部缺血性视神经病变(AION)患者图形视觉诱发电位(P-VEP)检查结果与预后间的关系。方法:选择2016年12月-2019年12月于我院就诊并确诊的AION患者作为研究对象,入院后接受综合治疗,治疗后评估患者的视功能,评价患者的治疗效果,采用相关性分析探究患者入院后P-VEP检查结果与经治疗后患者视功能改善值间的相关性。结果:研究组15'棋盘格和60'棋盘格P100波潜伏时均高于对照组,P100波振幅均低于对照组,差异均具有统计学意义(P0.05)。治疗后3个月AION患者最佳矫正视力和视野平均敏感度(MS)高于治疗前,视野平均缺失值(MD)低于治疗前,差异均具有统计学意义(P0.05)。AION患者治疗前后视力差值与15'棋盘格P100波振幅呈正相关,视野MD差值和视野MS差值与P-VEP四项反应值不具有相关性。结论:P-VEP检查结果 15'棋盘格P100波振幅与患者视力改善差值间存在显著的正相关性,可提示患者视功能恢复程度及预后。  相似文献   

19.
PurposeTo investigate whether suppression of blue light can improve visual function in patients with short tear break up time (BUT) dry eye (DE).MethodsTwenty-two patients with short BUT DE (10 men, 12 women; mean age, 32.4 ± 6.4 years; age range, 23–43 years) and 18 healthy controls (10 men, 8 women; mean age, 30.1 ± 7.4 years; age range, 20–49 years) underwent functional visual acuity (VA) examinations with and without wearing eyeglasses with 50% blue light blocked lenses. The functional VA parameters were starting VA, functional VA, and visual maintenance ratio.ResultsThe baseline mean values (logarithm of the minimum angle of resolution, logMAR) of functional VA and the visual maintenance ratio were significantly worse in the DE patients than in the controls (P < 0.05), while no significant difference was observed in the baseline starting VA (P > 0.05). The DE patients had significant improvement in mean functional VA and visual maintenance ratio while wearing the glasses (P < 0.05), while there were no significant changes with and without the glasses in the control group (P > 0.05),ConclusionsProtecting the eyes from short-wavelength blue light may help to ameliorate visual impairment associated with tear instability in patients with DE. This finding represents a new concept, which is that the blue light exposure might be harmful to visual function in patients with short BUT DE.  相似文献   

20.
ObjectiveIt is important that assays used for insulin and C-peptide testing are metrologically traceable and meet predefined quality specifications. Realizing this is the mission statement of the Insulin Standardization Work Group and the C-Peptide Standardization Committee.Materials and methodsBoth groups adopt the traceability concept as described by the International Organization for Standardization. It is based on a higher-order reference measurement system, defining the measurand and système internationale d’unités, and comprising a primary calibrator (highly purified standard materials with certified property values in mass units of milligram), trueness-based reference measurement procedures (ReMPs) and secondary calibrators. Both groups developed already isotope dilution-mass spectrometry candidate ReMPs, investigated different options of secondary calibrators and negotiated with the World Health Organization to obtain the required certified primary calibrators. Meanwhile, the first studies have been done to look into the feasibility of using a reference measurement system for the purpose of establishing traceability of immunoassays, while judging on their quality of performance.ResultsThe studies showed that native sera, assigned with reference measurement values, are the best secondary calibrators. They also demonstrated the feasibility of establishing traceability of immunoassays from a method comparison study with a candidate ReMP and use of the relationship of the results as a recalibration basis.ConclusionBoth groups aim at completing the establishment of the reference measurement system. They intend to provide the in-vitro diagnostic manufacturers with a panel of single-donor sera assigned with ReMP values for recalibration of their assays and to follow-up this process by periodic surveillance.  相似文献   

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