A practical analytic model for daylight

www.cs.utah.edu Figure 1: Left: A rendered image of an outdoor scene with a constant colored sky and no aerial perspective. Right: The same image with a physically-based sky model and physically-based aerial perspective. Sunlight and skylight are rarely rendered correctly in computer graphics. A major reason for this is high computational expense. Another is that precise atmospheric data is rarely available. We present an inexpensive analytic model that approximates full spectrum daylight for various atmospheric conditions. These conditions are parameterized using terms that users can either measure or estimate. We also present an inexpensive analytic model that approximates the effects of atmosphere (aerial perspective). These models are fielded in a number of conditions and intermediate results verified against standard literature from atmospheric science. These models are analytic in the sense that they are simple formulas based on fits to simulated data; no explicit simulation is required to use them. Our goal is to achieve as much accuracy as possible without sacrificing usability

Periodontitis as a Risk Factor for Preterm Low Birth Weight Infants: A Clinico-Epidemiological Evaluation

Background: There is growing evidence showing that a number of complex human diseases are caused or are at least influenced by periodontal diseases. Such diseases include cardiovascular diseases, respiratory diseases, diabetes mellitus, and osteoporosis. Aim: The aim of the present study was to evaluate periodontal diseases as a risk factor for preterm low birth weight infants. Methods: A case‑control study with a selection ratio of 1:1 was performed using 150 cases and 150 controls, who delivered their babies at Vanivilas Hospital, Bangalore, India, over a 3‑months period from January 2012–March 2012. Cases were defined as mothers delivering an infant weighing less than 2,500 gms and born before 37‑weeks gestation. Controls were mothers delivering an infant weighing more than 2,500 gms and born after 38‑weeks gestation. Patients were evaluated for age, socioeconomic status, obstetric risk, nutritional status, maternal morbidity, infections, toxic exposure, antenatal care, infant characters, through hospital records and personal questionnaire by incharge team members. Oral examination was performed using Extent and severity index, Sulcus Bleeding Index. Results: Cases and controls did not reveal any significant difference when compared for age, socioeconomic status, obstetric risk, nutrition, maternal morbidity, and antenatal care. Periodontal disease was more severe and extensive in cases when compared with control and the difference was statistically significant (P<0.001). Bleeding index scores were higher in cases as compared to control and was statistically significant (P<0.001). Conclusion: Within the limits of this study, it is concluded that a poor periodontal health status of the mother may be a potential risk factor for a preterm low birth weight.Keywords: Cytokines, preterm low birth weight, periodontitis, socioeconomic statu

Treatment of postmastectomy pain with ambulatory continuous paravertebral nerve blocks: a randomized, triple-masked, placebo-controlled study.

BackgroundWe aimed to determine with this randomized, triple-masked, placebo-controlled study if benefits are afforded by adding a multiple-day, ambulatory, continuous ropivacaine paravertebral nerve block to a single-injection ropivacaine paravertebral block after mastectomy.MethodsPreoperatively, 60 subjects undergoing unilateral (n = 24) or bilateral (n = 36) mastectomy received either unilateral or bilateral paravertebral perineural catheter(s), respectively, inserted between the third and fourth thoracic transverse process(es). All subjects received an initial bolus of ropivacaine 0.5% (15 mL) via the catheter(s). Subjects were randomized to receive either perineural ropivacaine 0.4% or normal saline using portable infusion pump(s) [5 mL/h basal; 300 mL reservoir(s)]. Subjects remained hospitalized for at least 1 night and were subsequently discharged home where the catheter(s) were removed on postoperative day (POD) 3. Subjects were contacted by telephone on PODs 1, 4, 8, and 28. The primary end point was average pain (scale, 0-10) queried on POD 1.ResultsAverage pain queried on POD 1 for subjects receiving perineural ropivacaine (n = 30) was a median (interquartile) of 2 (0-3), compared with 4 (1-5) for subjects receiving saline (n = 30; 95% confidence interval difference in medians, -4.0 to -0.3; P = 0.021]. During this same period, subjects receiving ropivacaine experienced a lower severity of breakthrough pain (5 [3-6] vs 7 [5-8]; P = 0.046) as well. As a result, subjects receiving perineural ropivacaine experienced less pain-induced physical and emotional dysfunction, as measured with the Brief Pain Inventory (lower score = less dysfunction): 14 (4-37) versus 57 (8-67) for subjects receiving perineural saline (P = 0.012). For the subscale that measures the degree of interference of pain on 7 domains, such as general activity and relationships, subjects receiving perineural saline reported a median score 10 times higher (more dysfunction) than those receiving ropivacaine (3 [0-24] vs 33 [0-44]; P = 0.035). In contrast, after infusion discontinuation, there were no statistically significant differences detected between treatment groups.ConclusionsAfter mastectomy, adding a multiple-day, ambulatory, continuous ropivacaine infusion to a single-injection ropivacaine paravertebral nerve block results in improved analgesia and less functional deficit during the infusion. However, no benefits were identified after infusion discontinuation