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Background: There are limited data in the relationship between the minimal erythema dose (MED) of 308‐nm monochromatic excimer light (MEL) and 311‐nm Narrowband UVB (NB‐UVB). Objective: To establish a predictive model of the relationship between MEDs of both wavelengths. Methods: An MED test was performed on the back of 40 healthy Thai volunteers. One side was irradiated with 308‐nm MEL, and the opposite side was irradiated with 311‐nm NB‐UVB. The correlation and a predictive model of the relationships were then analyzed. Results: There was a positive correlation in the MED of both wavelengths (r = 0.82, p < 0.001). A predicted MED of 308‐nm MEL was based on Y = 62.421 + 0.439X, where Y and X were a predicted MED of 308‐nm MEL and an actual 311‐nm NB‐UVB, respectively. This model could predict an MED of 308‐nm MEL by using an actual MED of 311‐nm NB‐UVB with a root mean square difference of 13.64%, and a mean bias difference of 0.63%. Limitation: All volunteers were Fitzpatrick's skin phototype type IV. The predictive model might not generalize to other skin phototypes. Conclusion: We established a predictive model of the relationship between MED of 308‐nm MEL and 311‐nm NB‐UVB with acceptable accuracy. [ABSTRACT FROM AUTHOR]

Background: Visualizing the ultraviolet (UV) dose on skin serve as an intuitive approach to ensure appropriate sunscreen usage and reduce the risk of erythema. UV dose is determined by a number of external factors, such as properties of sunscreens, weather, and type of outdoor activity. We propose a framework for visualizing UV doses that considers various external factors. Materials and methods: First, the skin of a three‐dimensional human model was represented using triangular meshes, and various static postures and dynamic motions were simulated to express outdoor activities. Then, we evaluated the persistency and insufficiency properties of sunscreen, which are time dependent and directly affect the effectiveness of the sunscreen skin protection factor (SPF) during UV exposure. Finally, to calculate the UV dose in real time, we tracked the trajectory of the sun and motion of the skin while considering the time‐dependent properties of sunscreen. Results: An S/W system was implemented based on the proposed framework to visualize the distribution of UV doses through dynamic color changes in exposed skin areas. The color types include true colors, which represent the minimum erythema dose (MED), and pseudo colors representing states before 1 MED is reached. We devised various examples to discuss the usability of the proposed framework. Conclusion: The system conveniently displays the MED according to an individual's skin phototype. When the properties of a wide range of commercial sunscreens are added to the system database, it is expected that the rate of appropriate sunscreen usage by customers will increase. [ABSTRACT FROM AUTHOR]

Guo et al. introduced the quantum feed‐forward control (QFFC) before the minimum‐error discrimination (MED) measurement to effectively discriminate between two nonorthogonal states via an amplitude‐damping (AD) noise. However, the discrimination is inversely proportional to the success probability. To solve the problem, we propose an improved scheme where only preweak measurement and feed‐forward operations are retained before the MED measurement. Interestingly, we find the improved scheme achieves a similar effect of discrimination as the scheme proposed by Guo et al. Most importantly, the value of success probability is constant to 1. [ABSTRACT FROM AUTHOR]

Summary: Carotenoids, a class of phytonutrients, have been well established to boost skin's innate resistance against ultraviolet (UV) B‐induced erythema (sunburn). Many of the published clinical studies thus far have focused on the measurement of erythema as the primary clinical indicator of skin protection against UVB radiation. More recent studies have shown that carotenoid supplementation provides even more skin protection than previously shown as new clinical and molecular endpoints beyond UVB‐induced erythema have been reported. These recent studies have demonstrated that carotenoids also provide photoprotection against UVA‐induced pigmentation and inhibit molecular markers of oxidative stress such as intercellular adhesion molecule 1, heme oxygenase‐1, and matrix metalloproteinases 1 and 9. This article provides a comprehensive review of the published clinical evidence on skin benefits of carotenoids in the last five decades and indicates new perspectives on the role of ingestible carotenoids in skin protection. [ABSTRACT FROM AUTHOR]

Since the detection of Bemisia tabaci Middle East‐Asia Minor 1 (MEAM1) species in Brazil in the early 1990s, this whitefly has been the predominant species and the main viral vector in the country. In this work, whiteflies were collected from commercial soybean fields near and far from greenhouses where Mediterranean (MED) species had previously been detected infesting vegetable crops. Results indicated that MEAM1 was the predominant whitefly species in soybean in most sampling sites, while MED was found colonizing soybean plants in open field conditions alone and/or with MEAM1 in several places. Among the tested insects, MED species was mostly detected harbouring the facultative endosymbiont Hamiltonella. We also detected cowpea mild mottle virus (CPMMV) infecting soybean plants. Transmission assays demonstrated that MED species was more efficient transmitting CPMMV from beans to beans and from soybean to soybean plants than MEAM1, while MEAM1 was more efficient in transmitting the virus from soybean to bean than MED. Performance assays indicated that adult emergence of both species on CPMMV‐infected soybean plants was higher when compared with the emergence on healthy plants. Moreover, nonviruliferous MED and MEAM1 adults preferred to settle more often on healthy plants, while viruliferous adults settled more often on CPMMV‐infected soybean plants. As MED has already been found in soybean open fields in São Paulo and Paraná States, Brazil, and it is a good vector of CPMMV, we anticipate problems related to whitefly management and to increase in the incidence of the virus in soybean. [ABSTRACT FROM AUTHOR]

In this article, a small broadband dual‐polarized antenna is presented. The main structure consists of the four irregular polygon patches printed on the bottom layer of the substrate, two trapezoidal coupling plates printed on the top layer of the substrate, and a box‐shaped reflector at the back of the substrate at resonance distance. Design principles are based on the rules of complementary antennas, cross dual‐polarized antennas, and aperture antennas. The proposed antenna has technical specifications such as impedance bandwidth 48% (1.7‐2.7 GHz) with lower than 15 dB return loss, port‐to‐port isolation about 32 dB, high pattern stability, and half‐power beam width about 63 ± 9°. The antenna measurement results confirm these. At the end, a comparison between the proposed antenna and the other antennas of this type is presented. The proposed antenna has smaller dimensions, high gain, high port isolation, and excellent pattern stability over the whole bandwidth. The proposed antenna can be used in the base transceiver stations (BTSs) and multi input–multi output (MIMO) systems. [ABSTRACT FROM AUTHOR]

Bemisia tabaci has had a colorful nomenclatural past and is now recognized as a species complex. This new species framework has addedmany new areas of research including adding newinsight into the virus transmission specificity of the species in the B. tabaci species complex. There is awide disparity in what is known about the transmission of plant viruses by different members of the B. tabaci species complex. In this paper,we have synthesized the transmission specificities of the plant viruses transmitted by species belonging to the complex. There are five genera of plant viruses with members that are transmitted by species of the B. tabaci species complex. The transmission of viruses belonging to two of these, Begomovirus and Crinivirus, are well studied and much is known in regards to the relationship between species and transmission and etiology. This is in contrast to viruses of the genera, Torradovirus and Carlavirus, for which very little is known inregards to their transmission. This is the first attempt to integrate viral data within the newB. tabaci species complex framework. It is clear that matching historical transmission data with the current species framework is difficult due to the lack of awareness of the underlying genetic diversity within B. tabaci. We encourage all researchers to determine which species of B. tabaci they are using to facilitate association of phenotypic traits with particular members of the complex. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bemisia tabaci, a polyphagous insect with over 900 host plants, is an effective vector of more than 100 plant viruses. Being highly fecund, B. tabaci has the potential to develop insecticide resistance rapidly, as demonstrated by reports of use failures with MEAM1 and MED cryptic species (commonly known as biotypes B and Q respectively). Insecticide resistance management is a key component of pest management practices. The research herein studied season-long rotational management programs on poinsettia and their impact on the ratio of MEAM1:MED cryptic species in the surviving treated populations. RESULTS: In all four experiments, only three of the treatments completely eliminated the adult or immature whiteflies, but all significantly reduced the populations. Out of 18 active ingredients tested, dinotefuran (applied as a soil drench) was the most efficacious against both MEAM1 and MED cryptic species compared with the other chemical or biorational insecticides evaluated. Reduced susceptibility ofMED was reported against a variety of treatment regimes. CONCLUSION: Rotations can be used to manage MEAM1 and MED cryptic species and maintain a very low population level or completely eliminate Bemisiaonpoinsettia. It is imperative to continue to emphasize the importance of rotatingamongdifferent modes of action in pest management programs in order to retain effective chemistries for as long as possible in the market place. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

BACKGROUND: The nomenclature used with in the whitefly research community for different putative species within Bemisia tabaci (sensu Russell) remains highly variable and confused. This wasevident by the many different naming schemesre searchers were using in their presentations at the 1st International Whitefly Symposium in Kolymbari, Crete, Greece (20-24 May 2013). I wanted to try to document how we, as a community, have arrived at such a state of confused nomenclature. This also included an investigation of the nomenclature used in the literature (from 2002 to 2012) by means of two online search tools (Web of Science and Scirus). RESULTS: Nomenclatural data were collected at the 1st International Whitefly Symposium, based on oral presentations and posters. There were 17 different names used for the MED species and 12 different names used for the MEAM1 species of the B. tabaci species complex. Investigation of the literature revealed limited uptake of the intermediate names. CONCLUSION: The intermediate names for the various species in the B. tabaci species complex - MED, MEAM1, New World, etc. - are not being used by the wider whitefly community. Tomove forwarrd as a community, we must work towards a formal revision of the B. tabaci complex. [ABSTRACT FROM AUTHOR]

Maximum‐eigenvalue‐detection (MED) and maximum‐eigenvalue geometric‐mean (ME‐GM) are attractive eigenvalue‐based spectrum sensing (EBSS) schemes for cognitive radio (CR). The first objective of this paper is to present an analytical probability of detection (PD) expression for MED. The evaluated expression matches the simulation results well. Many of the existing analytical results for EBSS schemes are based on the asymptotic Tracy‐Widom (TW) distribution; however, for small or moderate sample length, N and secondary users, M the distribution lacks accuracy. Recently, adjusted centring and scaling parameters have been presented to improve the accuracy of the TW distribution for this practical scenario; thus, the second objective is to present the adjusted‐TW expressions (probability of false alarm (PFA), threshold and PD) for MED and ME‐GM. The proposed results show an improved accuracy for moderate N when M is small. To improve the accuracy for small N the authors propose to use an exact cumulative distribution function of the maximum eigenvalue. Hence the third objective of the paper is to present the exact analytical expressions for MED. The exact approach is then applied to ME‐GM, where an asymptotic expression for the GM is employed. The exact analysis exhibits a higher accuracy for both MED and ME‐GM. [ABSTRACT FROM AUTHOR]

To observe the alteration ultraviolet radiation (UVR) of skin's tolerance after its exposure to the small dose of UVR under the protection of sunscreen. Eleven subjects who applied sunscreen were exposed to 0.75 dose minimal persistent pigment darkening (MPPD) and minimal erythema dose (MED) by the Phototherapy Unit for 4 weeks. Each week their MPPDs and MEDs were measured by solar simulator. Meanwhile, SPECTCOLOMETER and VISIOSCAN VC98 were used to detect the test areas and control areas. The values of MPPD and MED increased significantly after the exposure to UVR. But there were no visible changes on the surface of skin's texture. With the protection of sunscreen, the UVR tolerance of skin was greatly increased after the skin's exposure to the small dose UV. [ABSTRACT FROM AUTHOR]

Background Cocoa beans fresh from the tree are exceptionally rich in flavanols. Unfortunately, during conventional chocolate making, this high antioxidant capacity is greatly reduced due to manufacturing processes. Aim To evaluate the photoprotective potential of chocolate consumption, comparing a conventional dark chocolate to a specially produced chocolate with preserved high flavanol (HF) levels. Methods  A double-blind in vivo study in 30 healthy subjects was conducted. Fifteen subjects each were randomly assigned to either a HF or low flavanol (LF) chocolate group and consumed a 20 g portion of their allocated chocolate daily. The minimal erythema dose (MED) was assessed at baseline and after 12 weeks under standardized conditions. Results In the HF chocolate group the mean MED more than doubled after 12 weeks of chocolate consumption, while in the LF chocolate group, the MED remained without significant change. Conclusions Our study demonstrated that regular consumption of a chocolate rich in flavanols confers significant photoprotection and can thus be effective at protecting human skin from harmful UV effects. Conventional chocolate has no such effect. [ABSTRACT FROM AUTHOR]

Background/purpose: Monochromator phototesting, to measure the minimal erythemal dose (MED), is useful in investigating patients with abnormal photosensitivity at different wavelengths. It relies on access to reliable, up-to-date data on the MED in normal individuals. The purpose of this study was to determine MED in normal subjects at different wavebands and compare these with historical controls. Methods: The study group consisted of 415 normal individuals (349 males) of skin types I–III living in Scotland. Age range was 18–83 years (median 31 years). Phototesting was performed using a monochromator at prescribed wavelengths from 295 to 430 nm. All calibrations were traceable to the National Physical Laboratory. Quality systems were maintained to ISO 9001 and ISO 17025 international standards and ultraviolet (UV) measurements accredited by the United Kingdom Accreditation Service (UKAS). Results: The 95% reference interval (99% confidence interval for this) ranged from 6.8 to 27 mJ/cm2 at 295 nm to >82 000 mJ/cm2 at 430 nm. Conclusions: Results of the current investigation are broadly in agreement with values published 25 years ago by this centre. This validates the phototesting process based on the use of monochromators with attention to careful control of conditions during UV exposure and MED reading, supported by dosimetric calibration. [ABSTRACT FROM AUTHOR]

Background Ultraviolet (UV) irradiation of the skin leads to acute inflammatory reactions, such as erythema, sunburn, and chronic reactions, including premature skin aging and skin cancer. Aim In this study, the effects of a topical antioxidant mixture consisting of vitamin C, ferulic acid, and phloretin on attenuating the harmful effects of UV irradiation on normal healthy volunteers were studied using biomarkers of skin damage. Subjects/methods Ten subjects (age, 18–60 years; Fitzpatrick skin types II and III) were randomized and treated with antioxidant product or vehicle control on the lower back for four consecutive days. On day 3, the minimal erythema dose (MED) was determined for each subject at a different site on the back. On day 4, the two test sites received solar-simulated UV irradiation 1–5× MED at 1× MED intervals. On day 5, digital images were taken, and 4-mm punch biopsies were collected from the two 5× MED test sites and a control site from each subject for morphology and immunohistochemical studies. Results UV irradiation significantly increased the erythema of human skin in a linear manner from 1× to 5× MED. As early as 24 h after exposure to 5× MEDs of UV irradiation, there were significant increases in sunburn cell formation, thymine dimer formation, matrix metalloproteinase-9 expression, and p53 protein expression. All these changes were attenuated by the antioxidant composition. UV irradiation also suppressed the amount of CD1a-expressing Langerhans cells, indicating immunosuppressive effects of a single 5× MED dose of UV irradiation. Pretreatment of skin with the antioxidant composition blocked this effect. Conclusion This study confirms the protective role of a unique mixture of antioxidants containing vitamin C, ferulic acid, and phloretin on human skin from the harmful effects of UV irradiation. Phloretin, in addition to being a potent antioxidant, may stabilize and increase the skin availability of topically applied vitamin C and ferulic acid. We propose that antioxidant mixture will complement and synergize with sunscreens in providing photoprotection for human skin. [ABSTRACT FROM AUTHOR]

Background: Sun exposure and skin phototype are the most relevant risk factors for skin cancer. Colombia has high levels of ultraviolet radiation during the whole year, therefore, both, high UVI's and outdoor worker's daily activities, in our country are very important risk factors for the development of cutaneous cancer. To date no study has evaluated the usefulness of Fitzpatrick's skin phototype classification in Colombians and its correlation with the minimal erythema dose (MED) and constitutional skin color. Such information is gaining importance in other nations due to the fact that several country's population is becoming more ethnically diverse. Objectives: To determine the skin phototype, accumulated sun exposure, sun protection behavior, MED and phenotype in a Colombian school population. Methods: Last year high school students from the western Antioquia were invited to participate by phone and letter through their respective school directors. A self-questionnaire was handled to each student. A representative sample of the universe was selected for a medical examination by a dermatologist in order to validate the results of the self-questionnaire. The constitutional skin color was determined with the chromameter CR 300 Minolta®. The MED was defined as the minimal dose of UVB being able to induce erythema 24 h later. Results: Eight schools of the area agreed to participate in the study, and a total of 911 students (58% girls and 42% boys) filled-out the self-questionnaire. Sun exposure in the majority of individuals was in a level between moderate and very high. Ninety percent of students do not use any sun protection device or cream. Only a 50% of concordance between self-assessed skin phototype vs. medical skin phototype was found, and the highest concordance corresponded to skin phototype II (82%). There was a marked difference in skin photosensitivity of Colombians compared with reports in Caucasians. We observed a marked overlapping in MED's and L* values in phototypes II and III. Conclusions: The Fitzpatrick's classification was not useful in Hispanic populations such as ours. Therefore, a new skin-phototype classification system is required. In our population the constitutional color was a good predictor of the MED but it did not correlate with skin phototype. The self-assessed questionnaire method was not useful to determine skin cancer risk in our population. The majority of this population has light skin phototypes and is highly exposed to solar UV radiation without proper protection. [ABSTRACT FROM AUTHOR]

Background: Psoriasis is a common and relapsing disease, which is both physically and psychologically disabling. Narrowband UVB (NB-UVB) is used in fair-skinned population in suberythemogenic doses with good results; however, in the darker skin population (skin types III, IV, V) erythemogenic doses have not been thoroughly investigated. Aim: A left–right bilateral comparative trial was carried out to compare the suberythemogenic dose of NB-UVB vs. erythemogenic dose in the treatment of dark-skinned psoriatic patients. Patients and methods: The study was conducted on 20 patients with chronic plaque psoriasis. The left side was treated with the dose causing minimal erythema [100% of minimal erythema dose (MED)] while the right side received 70% of this MED (suberythemogenic side). Results: Our results revealed no statistically significant difference in PASI final and in the percentage of reduction of PASI score between both sides as well as the total number of sessions ( P-value>0.05), while the total cumulative UVB dose on the suberythemogenic side was significantly lower ( P-value<0.001). Conclusion: Our study recommends reducing the dose regimen of NB-UVB and consequently the cumulative UVB dose by using the suberythemogenic dosing schedule even in dark skin population. [ABSTRACT FROM AUTHOR]

Abstract: Primary hyperalgesia to mechanical and thermal stimuli are major clinical symptoms of inflammatory pain and can be induced experimentally by ultraviolet-B (UV-B) irradiation in humans. We set-up a pig model in order to have more options for pharmacological intervention on primary hyperalgesia. Pig skin was irradiated with a dose one- to threefold higher than the minimum erythema dose (MED) and investigated for mechanical and heat responsiveness 24 and 48h post UV-B treatment. C-fiber activation upon mechanical and thermal stimulation was assessed indirectly by extent of the axon reflex erythema (flare) measured by laser Doppler imaging. Mechanical stimulation with von Frey filaments (100mN) induced flare responses in UV-B treated skin at 24 and 48h, but no effect was measured in normal untreated skin. Increased mechanical stimulation (600mN) elicited a small flare response in normal skin in an area of 1.8cm2 on average that was extending about 2.5cm2 in the UV-B irradiated sites. Thermal stimuli provoked in normal pig skin flare areas of approximately 2cm2 (45°C, 10s) and 4.5cm2 (47°C, 10s) which increased to about 3.5cm2 (45°C) and 5.5cm2 (47°C) following UV-B irradiation at 24 and 48h. No significant differences of mechanically or thermally induced hypersensitivity were seen between 24 and 48h after irradiation. We conclude that UV-B induced mechanical and heat sensitization of primary afferent nociceptors can be assessed in pig skin, providing a new human-like model of primary hyperalgesia. Sensitization of primarily mechano-insensitive (silent) nociceptors, which are underlying the flare response in humans, most probably contributes to the observation presented here. [Copyright &y& Elsevier]

This article discusses soil hydrophobicity and the persistence and initial severity of soil water repellency. According to the authors, soil water repellency is commonly assessed using the Molarity of Ethanol and or Critical Surface Tension tests. The initial severity of water repellency is a thermodynamic measurement of Critical Surface Tension and the Water Droplet Penetration Time test is a kinetic measurement indicating the persistence of water repellency. The authors suggest that the surface free energy contribution to the free energy of activation of wetting is given by the difference between the cohesive energy of the wetting solution and the molecular film adsorbed on the soil grains.

Transcription regulation has been responsible for organismal complexity and diversity in the course of biological evolution and adaptation, and it is determined largely by the context-dependent behavior of cis-regulatory elements (CREs). Therefore, understanding principles underlying CRE behavior in regulating transcription constitutes a fundamental objective of quantitative biology, yet these remain poorly understood. Here we present a deterministic mathematical strategy, the motif expression decomposition (MED) method, for deriving principles of transcription regulation at the single-gene resolution level. MED operates on all genes in a genome without requiring any a priori knowledge of gene cluster membership, or manual tuning of parameters. Applying MED to Saccharomyces cerevisiae transcriptional networks, we identified four functions describing four different ways that CREs can quantitatively affect gene expression levels. These functions, three of which have extrema in different positions in the gene promoter (short-, mid-, and long-range) whereas the other depends on the motif orientation, are validated by expression data. We illustrate how nature could use these principles as an additional dimension to amplify the combinatorial power of a small set of CREs in regulating transcription. [ABSTRACT FROM AUTHOR]