A Legibility Equation for Determining Ideal Viewing Areas in Lecture Halls.

Text presented in modern lecture halls often simultaneously appears on multiple visual media (e.g., blackboard, projection screens, TV) that have different locations, geometries, orientations, and lighting conditions. An ideal viewing area inside which all text is legible to the entire audience could be calculated using equations that predict the spatial legibility of text viewed from any directions across the lecture hall. However, among the 95 legibility equations ever published in the literature, none can serve this purpose. After using ten assumptions to narrow down the research scope, this study applies a constant-solid-angle hypothesis to develop the demanded equation from the existing Howett’s equation (1983). This derived equation examines seven critical factors but the surrounding luminance of the ambient environment, which may reduce its accuracy. The hypothesis is first verified consistent with how retinal images of text activate cones in the centre fovea of an observer’s eyes, then tested in the lighting laboratory at the University of Michigan Transportation Research Institute using legibility data collected from 3 subjects in a pilot experiment and 20 subjects in a follow-up main experiment. Both experimental setups abide by the typical viewing conditions surveyed in 38 lecture halls at the University of Michigan. The outcomes show that the hypothesis holds when incident angle is 0-65.7 degree, but it does not hold when 65.7-82.8 degree (the largest angle examined). The derived equation is thus accordingly improved. Moreover, this study uses 20 human subjects with a modified setup at four different ambient light levels in the same laboratory to verify the negligible effect of ambient light on legibility. The validated equation is then improved and used as the underlying algorithm for developing a computation-program-aided design method in MatLab. This method allows architects to find an overlapped two-dimensional ideal viewing area of text viewed in modern lecture halls along any viewing plane, such as that parallel to the sloped floor at eye height level. This program-aided method is verified using a field experiment carried out in the lecture hall in the Art & Architecture building at the University of Michigan.Ph.D.ArchitectureUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/58415/1/hcai_1.pd

New definition of legibility index to examine off-axis viewing of text and graphics

IESNA Annual Conference: Light Matters 2007: Integrating Light Into Our Environments. General Lighting Topics. January 28-30, 2007. Phoenix, AZ.Reading text and graphics is a common issue in lighting design and practice. Legibility of text and graphics is often measured using the Legibility Index, conventionally defined as the distance at which material can be read with perfect accuracy (the legibility distance) divided by the character height. The ratio equals to the inverse tangent of the visual angle V. This definition assumes the material to be read is perpendicular to the viewer, which is always not true. Off-axis viewing of text and graphics is common in reality, yet rarely researched. To examine off-axis legibility, this paper has developed a new definition of the Legibility Index, defined as the inverse square root of solid angle ω subtended by the target, based on a hypothesis that the three-dimensional solid angle, rather than the two-dimensional visual angle, captures how people recognize text and graphics. This hypothesis has been verified in light of how retinal images activate cones. When viewed, text or graphics form a retinal image that activates the underlying cones in the center fovea of viewer’s eyes. Legibility is then determined by the spatial distribution of these activated cones. For linear targets, their retinal images have only one dimension. Their activated cones are linearly distributed. Thus, visual angle is sufficient to examine the legibility of linear targets. For common nonlinear targets, their retinal images usually have two significant dimensions (width and height) and activate a two-dimensional collection of cones. Solid angle should be used to examine the legibility of these real viewing targets.http://deepblue.lib.umich.edu/bitstream/2027.42/65017/1/102438.pd

Glucagon-like peptide-1 receptor agonists as a disease-modifying therapy for knee osteoarthritis mediated by weight loss:Findings from the Shanghai Osteoarthritis Cohort

Objective: Obesity is a risk factor for knee osteoarthritis (KOA) development and progression. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are indicated for type 2 diabetes mellitus (T2DM) and obesity. However, whether KOA patients can benefit from GLP-1RA therapies has not been sufficiently investigated, especially in the long term. Methods: The Shanghai Osteoarthritis Cohort study is a prospective, observational, multicentre study of &gt;40 000 adults with clinically diagnosed osteoarthritis aged &gt;45 years in Shanghai. We identified all KOA participants with comorbid T2DM enrolled from 1 January 2011 to 1 January 2017. Primary outcome was incidence of knee surgery after enrolment. Secondary outcomes included pain-relieving medication use, number of intra-articular therapies, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and medial femorotibial joint cartilage thickness. To evaluate the effects of GLP-1RA, we performed before-and-after comparison and comparison with participants who had no GLP-1RA exposure. Results: For an intergroup comparison (non-GLP-1RA vs GLP-1RA), more weight loss (adjusted mean difference in weight change from baseline-7.29 kg (95% CI-8.07 to-6.50 kg), p&lt;0.001) and lower incidence of knee surgery (93/1574 (5.9%) vs 4/233 (1.7%), adjusted p=0.014) were observed in the GLP-1RA group. Statistically significant differences in mean change from baseline for the WOMAC total and pain subscale scores were observed (adjusted mean difference in WOMAC total score-1.46 (95% CI-2.84 to-0.08), p=0.038; adjusted mean difference in WOMAC pain subscore-3.37 (95% CI-5.79 to-0.94), p=0.007). Cartilage-loss velocity of the medial femorotibial joint was significantly lower in the GLP-1RA group postadjustment for baseline characteristics (adjusted mean difference-0.02 mm (95% CI-0.03 to-0.002 mm), p=0.004). For the before-and-after comparison within the GLP-1RA group, we observed a significant decrease of symptom-relieving medication consumption and cartilage loss velocity of medial femorotibial joint (after-treatment vs before-treatment:-0.03±0.05 vs-0.05±0.07 mm/year, p&lt;0.001). The association between GLP-1RA exposure and decreased incidence of knee surgery was mediated by weight reduction (mediation proportion: 32.1%), instead of glycaemic control (too small to calculate). Conclusion: With sufficient treatment duration, GLP-1RA therapies might be disease-modifying for KOA patients with comorbid T2DM, possibly mediated by weight loss. Further investigation is needed to elucidate effects of GLP-1RA on disease process, joint structure and patient-reported outcomes of osteoarthritis.</p

Ginsenoside Rg3 treats acute radiation proctitis through the TLR4/MyD88/NF-κB pathway and regulation of intestinal flora

ObjectivesThis study aimed to investigate the protective effect of ginsenoside Rg3 (GRg3) against acute radiation proctitis (ARP) in rats.MethodsWistar rats were randomly divided into control, model, dexamethasone-positive, GRg3 low-dose, GRg3 medium-dose, and GRg3 high-dose groups. The ARP rat model was established by a single 22-Gy irradiation of 6 MV) X-rays. The distribution and function of intestinal flora were detected using 16S rRNA high-throughput sequencing, rectal tissue was observed by hematoxylin and eosin (H&amp;E) staining, the expression of interleukin 1β (IL-1β) and IL-10 inflammatory factors was detected by ELISA, and mRNA and protein expression of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) were detected by RT-qPCR and Western blotting, respectively.ResultsGRg3 improved the symptoms of ARP in rats in a dose-dependent manner. The species distribution of intestinal flora in GRg3 rats was significantly different from that in ARP rats. These differences were more significant in the high-dose group, where the numbers of Ruminococcus, Lactobacillus, and other beneficial bacteria were significantly increased, whereas those of Escherichia, Alloprevotella, and other harmful bacteria were decreased. In addition, GRg3 was closely related to amino acid metabolism. After GRg3 treatment, the mRNA and protein expression of TLR4, MyD88, and NF-κB in rectal tissue was significantly down-regulated, and the level of downstream inflammatory factor IL-1β decreased, whereas that of IL-10 increased.ConclusionOur study indicated GRg3 as a new compound for the treatment of ARP by inhibiting the TLR4/MyD88/NF-κB pathway, down-regulating the expression of proinflammatory factors, thus effectively regulating intestinal flora and reducing inflammatory reactions

Detection Methods and Clinical Applications of Circulating Tumor Cells in Breast Cancer

Circulating Tumor Cells (CTCs) are cancer cells that split away from the primary tumor and appear in the circulatory system as singular units or clusters, which was first reported by Dr. Thomas Ashworth in 1869. CTCs migrate and implantation occurs at a new site, in a process commonly known as tumor metastasis. In the case of breast cancer, the tumor cells often migrate into locations such as the lungs, brain, and bones, even during the early stages, and this is a notable characteristic of breast cancer. Survival rates have increased significantly over the past few decades because of progress made in radiology and tissue biopsy, making early detection and diagnosis of breast cancer possible. However, liquid biopsy, particularly that involving the collection of CTCs, is a non-invasive method to detect tumor cells in the circulatory system, which can be easily isolated from human plasma, serum, and other body fluids. Compared to traditional tissue biopsies, fluid sample collection has the advantages of being readily available and more acceptable to the patient. It can also detect tumor cells in blood earlier and in smaller numbers, possibly allowing for diagnosis prior to any tumor detection using imaging methods. Because of the scarcity of CTCs circulating in blood vessels (only a few CTCs among billions of erythrocytes and leukocytes), thorough but accurate detection methods are particularly important for further clinical applications