bluuebunny/crossref_metadata_2025 huggingface dataset:
Suitability of LiDAR point density and derived landform curvature maps for channel network extraction
Authors: Pirotti Francesco , Tarolli Paolo
Published: February 2010

This study uses landform curvature as an approach for channel network extraction. We considered a study area located in the eastern Italian Alps where a high‐quality set of LiDAR data was available and where channel heads and related channel network were mapped in the field. In the analysis, we derived 1‐m DTMs from different ground LiDAR point densities, and we used different smoothing factors for the landscape curvature calculation in order to test the suitability of the LiDAR point density and the derived curvature maps for the recognition of channel network. This methodology is based on threshold values of the curvature calculated as multiples (1–3 times) of the standard deviation of the curvature. Our analyses suggested that (i) the window size for curvature calculations has to be a function of the size of the features to be detected, (ii) a coarse ground LiDAR point density could be as useful as a finer one for the recognition of main channel network features and (iii) rougher curvature maps are not optimal as they do not explore a sufficient range at which features occur, while smoother curvature maps overcome this problem and are more appropriate for the extraction of surveyed channels. Copyright © 2010 John Wiley & Sons, Ltd.
Sap flow of Artemisia ordosica and the influence of environmental factors in a revegetated desert area: Tengger Desert, China
Authors: Lei Huang , Zhi‐Shan Zhang , Xin‐Rong Li
Published: February 2010

Artemisia ordosica is considered as an excellent sand‐fixing plant in revegetated desert areas, which plays a pertinent role in stabilizing the mobile dunes and sustaining the desert ecosystems. Stem sap flows of about 10‐year‐old Artemisia ordosica plants were monitored continuously with heat balance method for the entire growing season in order to understand the water requirement and the effects of environmental factors on its transpiration and growth. Environment factors such as solar radiation, air temperatures, relative humidity, wind speed and precipitation were measured by the eddy covariance. Diurnal and seasonal variations of sap flow rate with different stem diameters and their correlation with meteorological factors and reference evapotranspiration were analysed. At the daily time scale, there was a significantly linear relationship between sap flow rate and reference evapotranspiration with a correlation coefficient of R2 = 0·6368. But at the hourly time scale, the relationship of measured sap flow rate and calculated reference evapotranspiration (ET0) was affected by the precipitation. A small precipitation would increase the sap flow and the ET0; however, when the precipitation is large, the sap flow and ET0 decrease. Leaf area index had a coincident variation with soil water content; both were determined by the precipitation, and meteorological factors were the most significant factors that affected the sap flow of Artemisia ordosica in the following order: solar radiation > vapour pressure deficit > relative humidity > air temperature > wind speed. The close correlation between daily sap flow rate and meteorological factors in the whole growing season would provide us an accurate estimation of the transpiration of Artemisia ordosica and rational water‐carrying capacity of sand dunes in the revegetated desert areas. Copyright © 2010 John Wiley & Sons, Ltd.
Geoelectrical structure and hydrogeological investigations of the southern Rif Cordillera (Morocco)
Authors: Zouhri Lahcen
Published: February 2010

An electrical prospecting survey is conducted in the Rharb basin, a semi‐arid region in the southern part of the Rifean Cordillera (Morocco) to delineate characteristics of the aquifer and the groundwater affected by the marine intrusion related to Atlantic Ocean. Analysis and interpretations of electrical soundings, bi‐logarithmic diagrams and the geoelectrical sections highlight a monolayer aquifer in the southern part, a multilayer system in the northern part of the Rharb basin and lenticular semi‐permeable formations. Several electrical layers have been deduced from the analysis of bi‐logarithmic diagrams: resistant superficial level (R0), conducting superficial level (C0), resistant level (R), intermediary resistant level (R′), conducting level (Cp) and intermediary layer of resistivity (AT). Spatial distribution of the resistivity deduced from the interpretation of apparent resistivity maps (AB = 400 and 1000 m) and the decreasing of resistivity values (35–10 Ωm), in particular in the coastal zone show that this heterogeneity is related to several anomalies identified in the coastal area, which result from hydraulic and geological processes: (i) heterogeneous hydraulic conductivity in particular in the southern part of the Rharb; (ii) lateral facies and synsedimentary faulting and (iii) the relationship between the electrical conductivity and chloride concentration of groundwater shows that salinity is the most important factor controlling resistivity. The distribution of fresh/salt‐water zones and their variations in space along geoelectrical sections are established through converting subsurface depth‐resistivity models. Copyright © 2010 John Wiley & Sons, Ltd.
Assessing the impact of mixing assumptions on the estimation of streamwater mean residence time
Authors: Fenicia Fabrizio , Wrede Sebastian , Kavetski Dmitri , Pfister Laurent , Hoffmann Lucien , Savenije Hubert H. G. , McDonnell Jeffrey J.
Published: February 2010

Catchment streamwater mean residence time (Tmr) is an important descriptor of hydrological systems, reflecting their storage and flow pathway properties. Tmr is typically inferred from the composition of stable water isotopes (oxygen‐18 and deuterium) in observed rainfall and discharge. Currently, lumped parameter models based on convolution and sinewave functions are usually used for tracer simulation. These traditional models are based on simplistic assumptions that are often known to be unrealistic, in particular, steady flow conditions, linearity, complete mixing and others. However, the effect of these assumptions on Tmr estimation is seldom evaluated. In this article, we build a conceptual model that overcomes several assumptions made in traditional mixing models. Using data from the experimental Maimai catchment (New Zealand), we compare a complete‐mixing (CM) model, where rainfall water is assumed to mix completely and instantaneously with the total catchment storage, with a partial‐mixing (PM) model, where the tracer input is divided between an ‘active’ and a ‘dead’ storage compartment. We show that the inferred distribution of Tmr is strongly dependent on the treatment of mixing processes and flow pathways. The CM model returns estimates of Tmr that are well identifiable and are in general agreement with previous studies of the Maimai catchment. On the other hand, the PM model—motivated by a priori catchment insights—provides Tmr estimates that appear exceedingly large and highly uncertain. This suggests that water isotope composition measurements in rainfall and discharge alone may be insufficient for inferring Tmr. Given our model hypothesis, we also analysed the effect of different controls on Tmr. It was found that Tmr is controlled primarily by the storage properties of the catchment, rather than by the speed of streamflow response. This provides guidance on the type of information necessary to improve Tmr estimation. Copyright © 2010 John Wiley & Sons, Ltd.
Comparative probabilistic assessment of the hydrological performance of reconstructed and natural watersheds
Authors: Keshta Nader , Elshorbagy Amin , Barbour Lee
Published: February 2010

The oil sands industry has committed to returning the mine sites to a productive condition. The reconstructed soil covers must have sufficient available water holding capacity (AWHC) to supply enough moisture over the growing season, to promote vegetation. In order to assess the sustainability of various soil cover alternatives, a generic, system dynamic watershed model entitled GSDW was used along with the available historical meteorological records to estimate the maximum soil moisture deficit and annual evapotranspiration fluxes. A probabilistic framework was adopted; consequently, frequency curves of the maximum annual moisture deficit values are constructed and used to assess the probability that various reconstructed and natural watersheds can provide the associated moisture demands. In general, the study showed a tendency for the reconstructed watershed to provide less moisture for evapotranspiration than natural systems. Watersheds of various soil types, layering, thicknesses and topography were studied. The gained knowledge was used to predict the possible performance of a hypothetical reclamation cover. The results indicated that the hypothetical cover performed in a similar manner to the thickest existing soil cover which confirmed a high probability of that cover to survive under the same existing climatic conditions. Moreover, this probabilistic framework was found to be useful for integrating information gained from natural watersheds (e.g. the canopy of mature natural systems and transfer the results to the reconstructed system). The results show that the canopy influenced the moisture deficit regime positively which signifies a greater possibility that reconstructed covers will adapt to vegetation type. In brief, the adopted approach enables better understanding of the response of reconstructed systems via multiple simulations of ‘what‐if’ scenarios using different soil/vegetation alternatives. Copyright © 2010 John Wiley & Sons, Ltd.
Suspended sediment and dissolved load budgets of two Amazonian rivers from the Guiana Shield: Maroni River at Langa Tabiki and Oyapock River at Saut Maripa (French Guiana)
Authors: Sondag Francis , Guyot Jean Loup , Moquet Jean Sébastien , Laraque Alain , Adele Georges , Cochonneau Gérard , Doudou Jean Claude , Lagane Christelle , Vauchel Philippe
Published: February 2010

This study presents the data collected within the framework of an Observatory of Research in Environment on the Amazonian Basin—the ORE HYBAM. It relates to the dissolved and solid loads of the two main rivers of French Guiana, the Maroni and Oyapock rivers, running on the Guiana Shield and draining respectively 64 230 and 24 630 km2. The low coefficient of variation of the average annual flows of the two rivers indicates an inter‐annual hydrological stability probably related to the immediate vicinity of the Atlantic Ocean. The sedimentary load is mainly composed of quartz and kaolinite. The total suspended solid (TSS) concentrations are among the world's lowest values; they range from 1 to 130 mg l−1 during the hydrological cycle, with averages of 22 and 12 mg l−1, for the Maroni and Oyapock rivers, respectively. The seasonal variability of these values is significantly higher than that of hydrologic flows, but without simple relationship with the discharge. Water chemical composition of the two rivers indicates a very weak mineralization, very similar to that found in the Amazonian rivers running on the Brazilian and Guianese shields, and in the Congo River and its tributaries in the Central African Shield. Seasonal variations are observed in both basins; they correspond to higher concentrations during low water stage (from October to February) and to more diluted water during the flood, from April to July. A signature enriched in Cl− is present at the Saut Maripa station on the Oyapock River indicating a more marked influence of the trade winds in this basin. The computation of atmospheric contributions to ions budget indicated a weak contribution for Ca2+ and Mg2+, which originates mainly from water‐rock interactions in both stations, while more than half of Na+ is derived from atmospheric inputs. Copyright © 2010 John Wiley & Sons, Ltd.
Sediment and solute transport on soil slope under simultaneous influence of rainfall impact and scouring flow
Authors: Guo Tailong , Wang Quanjiu , Li Dingqiang , Wu Laosheng
Published: February 2010

Soil erosion and nutrient losses with surface runoff in the loess plateau in China cause severe soil quality degradation and water pollution. It is driven by both rainfall impact and runoff flow that usually take place simultaneously during a rainfall event. However, the interactive effect of these two processes on soil erosion has received limited attention. The objectives of this study were to better understand the mechanism of soil erosion, solute transport in runoff, and hydraulic characteristics of flow under the simultaneous influence of rainfall and shallow clear‐water flow scouring. Laboratory flume experiments with three rainfall intensities (0, 60, and 120 mm h−1) and four scouring inflow rates (10, 20, 30, and 40 l min−1) were conducted to evaluate their interactive effect on runoff. Results indicate that both rainfall intensity and scouring inflow rate play important roles on runoff formation, soil erosion, and solute transport in the surface runoff. A rainfall splash and water scouring interactive effect on the transport of sediment and solute in runoff were observed at the rainfall intensity of 60 mm h−1 and scouring inflow rates of 20 l min−1. Cumulative sediment mass loss (Ms) was found to be a linear function of cumulative runoff volume (Wr) for each treatment. Solute transport was also affected by both rainfall intensity and scouring inflow rate, and the decrease in bromide concentration in the runoff with time fitted to a power function well. Reynolds number (Re) was a key hydraulic parameter to determine erodability on loess slopes. The Darcy–Weisbach friction coefficients (f) decreased with the Reynolds numbers (Re), and the average soil and water loss rate (Ml) increased with the Reynolds numbers (Re) on loess slope for both scenarios with or without rainfall impact. Copyright © 2010 John Wiley & Sons, Ltd.
Transient solution for radial two‐zone flow in unconfined aquifers under constant‐head tests
Authors: Chang Y. C. , Yeh H. D. , Chen G. Y.
Published: February 2010

The constant‐head test (CHT) is commonly employed to determine the aquifer parameters. This test is also applied to many environmental problems such as recovering light nonaqueous phase liquids (LNAPL) and controlling off‐site migration of contaminated groundwater in low‐transmissivity aquifers. A well skin near the wellbore may be produced due to the well construction or development and its formation properties are significantly different from the original ones. A more appropriate description for the skin effect on the aquifer system should treat the well skin as a different formation instead of using a skin factor. Thus, the aquifer system becomes a two‐zone formation including the skin and formation zones. This study presents a mathematical model developed for analyzing a two‐zone unconfined aquifer system and the associated solution for CHTs at partially penetrating wells under transient state. The solution of the model may be used either to identify the in situ aquifer parameters or to investigate the effects of the wellbore storage and well skin on the head changes in unconfined aquifers under constant‐head pumping. Copyright © 2010 John Wiley & Sons, Ltd.
Accelerated aging, natural aging, and small punch testing of gamma‐air sterilized polycarbonate urethane acetabular components
Authors: Kurtz S. M. , Siskey R. , Reitman M.
Published: February 2010

The objectives of this study were three‐fold: (1) to determine the applicability of the small punch test to characterize Bionate® 80A polycarbonate urethane (PCU) acetabular implants; (2) to evaluate the susceptibility of PCU acetabular implants to exhibit degradation of mechanical behavior following gamma irradiation in air and accelerated aging; and (3) to compare the oxidation of gamma‐air sterilized PCU following accelerated aging and 5 years of natural shelf aging. In addition to attenuated total reflectance‐Fourier transform infrared spectroscopy, we also adapted a miniature specimen mechanical test, the small punch test, for the deformable PCU cups. Accelerated aging was performed using ASTM F2003, a standard test that represents a severe oxidative challenge. The results of this study suggest that the small punch test is sufficiently sensitive and reproducible to discriminate slight differences in the large‐deformation mechanical behavior of Bionate 80A following accelerated aging. The gamma‐air sterilized PCU had a reduction of 9% in ultimate load after aging. Five years of shelf aging had little effect on the mechanical properties of the PCU. Overall, our findings suggest that the Bionate 80A material has greater oxidative stability than ultra‐high molecular weight polyethylene following gamma irradiation in air and exposure to a severe oxidative challenge. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Effect of calcination on microstructure and antibacterial activity of silver‐containing silica coatings
Authors: Durucan Caner , Akkopru Betul
Published: February 2010

Silver nanoparticle containing silica coatings on soda‐lime glass were prepared by the sol–gel process. The effect of thermal densification treatment at different temperatures in the range of 100–700°C on microstructure and antibacterial properties of the coatings were examined. The structural characterization of the coatings was performed by using scanning electron microscope, X‐ray diffraction, UV–visible and X‐ray photoelectron spectroscopy (XPS), and atomic force microscope (AFM). The antibacterial activity of the coatings was determined against Staphylococcus aureus by disk diffusion method. The mechanisms for formation and distribution of silver nanoparticles in the silica matrix with respect to the calcination temperature are discussed, and the correlation between the microstructural properties and antibacterial activity is described. The investigations revealed that silver nanoparticles were mainly in the metallic state during thermal treatments. AFM and XPS examinations proved that silver accumulated on the surface diffuse into glass substrate at higher calcination temperatures. A high level of antibacterial activity was observed for the coatings calcined at 300°C or lower temperatures allowing accommodation of silver on the surface of the coating. Silver diffusion into bulk via ion‐exchange with sodium and calcium ions from glass substrate during calcination at higher temperatures (500 or 700°C) resulted in apparent degradation in the antibacterial activity. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Clinical and virological effects of long‐term (over 5 years) lamivudine therapy
Authors: Hashimoto Yoshimasa , Suzuki Fumitaka , Hirakawa Miharu , Kawamura Yusuke , Yatsuji Hiromi , Sezaki Hitomi , Hosaka Tetuya , Akuta Norio , Kobayashi Masahiro , Saito Satoshi , Suzuki Yoshiyuki , Kobayashi Mariko , Arase Yasuji , Ikeda Kenji , Kumada Hiromitsu
Published: February 2010

Ideally, long‐term lamivudine therapy should not induce tyrosine–methionine–aspartate–aspartate (YMDD) mutants (reverse transcription [rt]; rt M204I/V) in patients with chronic hepatitis B. There is little or no information on the clinical features of patients who do not develop such mutants. We analyzed 368 patients who received lamivudine therapy for more than 6 months between 1995 and 2003. Among them, 98 patients were negative for YMDD mutants during 5‐year lamivudine therapy. Multivariate analysis identified hepatitis B e antigen (HBeAg) negativity, lack of cirrhosis, and high gamma glutamyltranspeptidase (GGTP) level as independent factors associated with lack of emergence of YMDD mutants during 5‐year treatment. In these 98 patients, 21 patients developed YMDD mutants in the 5‐year posttreatment follow‐up. Old age was identified as the only factor associated with the emergence of YMDD mutants during that period. For all patients, 53 showed no elevation of alanine aminotransferase (ALT) or viral load after emergence of YMDD mutants during 5 years. Short latency to emergence of YMDD mutants, mixed (tyrosine–isoleucine–aspartate–aspartate (YIDD) [rtM204I] + tyrosine–valine–aspartate–aspartate (YVDD) [rtM204V]) type, and low ALT level were identified as independent factors associated with elevation ALT or viral load. HBeAg negativity, lack of cirrhosis, and high GGTP level were associated with lack of emergence of YMDD mutants during 5‐year period. Young age protected against emergence of YMDD mutants over the 5‐year period. Moreover, after the emergence of YMDD mutants, short latency to the emergence of YMDD mutant, mixed type mutants, and low baseline ALT level were associated with elevation of ALT or viral load. J. Med. Virol. 82:684–691, 2010. © 2010 Wiley‐Liss, Inc.
Association of distinctive Epstein–Barr virus variants with gastric carcinoma in Guangzhou, southern China
Authors: Chen Jian‐Ning , Ding Yun‐Gang , Feng Zhi‐Ying , Li Hai‐Gang , He Dan , Du Hong , Wu Bin , Shao Chun‐Kui
Published: February 2010

To investigate the clinicopathologic features, Epstein–Barr virus (EBV) latency pattern and genome polymorphism of EBV‐associated gastric carcinoma (EBVaGC) in Guangzhou, an endemic area of nasopharyngeal carcinoma (NPC), an in situ hybridization assay of EBV‐encoded small RNA‐1 (EBER‐1) was used to identify the presence of EBV in 676 consecutive gastric carcinoma cases. EBV‐encoded proteins EBNA1, EBNA2, LMP1, and ZEBRA were detected by immunohistochemistry. EBV genome polymorphism was also analyzed by PCR and DNA sequencing. Of the 676 cases, 45 EBV‐positive cases (6.7%) were identified, including 37 (8.5%) male and 8 (3.3%) female cases. EBNA1 was detected in 42 cases (93.3%), while EBNA2, LMP1, and ZEBRA were all negative. In the EBV genome polymorphism analysis, type A strain, prototype F, type I, XhoI−, and del‐LMP1 variants were predominant among EBVaGC patients, accounting for 44 (97.8%), 37 (82.2%), 45 (100%), 34 (75.6%), and 42 (93.3%) cases, respectively. Moreover, a new hotspot mutation in the BamHI‐W1/I1 boundary region (148,972 T → C) was found in 39 (86.7%) of the 45 cases. The predominant EBV variants in EBVaGC in Guangzhou are prototype F, type I, and XhoI−, which are different from those in NPC in this area (predominant variant‐type “f”) and in EBVaGC in Latin American countries (predominant type “i” and XhoI+), suggesting that the EBV variants are not only geographically distributed but also disease restricted, and the pathogenic role of EBV in different EBV associated epithelial malignancies in different areas may be distinct. J. Med. Virol. 82:658–667, 2010. © 2010 Wiley‐Liss, Inc.
Human caliciviruses detected in Mexican children admitted to hospital during 1998–2000, with severe acute gastroenteritis not due to other enteropathogens
Authors: Gutiérrez‐Escolano Ana Lorena , Velázquez F. Raúl , Escobar‐Herrera Jaime , Saucedo Catalina López , Torres Javier , Estrada‐García Teresa
Published: February 2010

Few studies exist regarding the frequency of human caliciviruses as single etiologic agents in sporadic cases, or in outbreaks occurring in children hospitalized for acute gastroenteritis. In this study, a total of 1,129 children of <5 years of age and hospitalized due to acute diarrhea were enrolled from three main hospitals in Mexico City during a period of 3 years (March 1998 to December 2000). After analyzing all fecal samples for several enteropathogens, 396 stools that remained negative were further screened for human caliciviruses by RT‐PCR using a primer set specific to norovirus and sapovirus. Human caliciviruses were detected in 5.6% (22/396) of the children. The minimum incidence rate for 1999 were 5.3% (7/132) for 1999 and 7.8% (13/167) for 2000, since only fecal specimens that tested negative to other enteric pathogens were examined. Positive samples were further characterized using specific GI and GII primers and sequencing. Norovirus GII was detected in 19/22 samples, most of them were GII/4, while sapovirus GI/2 was detected in one sample. Associations between the presence of human calicivirus and clinical and epidemiological data revealed that diarrhea occurred with a seasonal pattern, and that children hospitalized due to human calicivirus disease scored an average of 13 ± 3.2 (SD) points on the Vesikari scale, which corresponded to severe episodes. These results highlight that human caliciviruses, by themselves, are enteropathogens of acute severe diarrhea among young Mexican children requiring hospitalization and that their detection is important in order to reduce the diagnosis gap. J. Med. Virol. 82:632–637, 2010. © 2010 Wiley‐Liss, Inc.
Effect of thermal treatments on phytochemicals in conventionally and organically grown berries
Authors: Sablani Shyam S , Andrews Preston K , Davies Neal M , Walters Thomas , Saez Hector , Syamaladevi Roopesh M , Mohekar Pallavi R
Published: February 2010

BACKGROUND: Consumer demand for organic foods is increasing despite a lack of conclusive evidence of nutritional superiority of organically grown produce. The objective of this investigation was to evaluate the effects of thermal treatments on phytochemicals in conventionally and organically grown berries. Two cultivars of conventionally and organically grown red raspberries and blueberries were analysed for total anthocyanins, total and specific phenolic compounds and total antioxidant activity. Fresh berries were thermally processed into cans and juice/puree with and without blanching, and the changes in phytochemicals were monitored.

RESULTS: Total anthocyanin and phenolic contents of berries were not influenced by the agricultural production system. Total antioxidant activity of berries was also not influenced by the production system, but antioxidant activity varied significantly between cultivars. After canning, total anthocyanins decreased by up to 44%, while phenolic contents and antioxidant activity of both berries generally increased by up to 50 and 53% respectively. The level of changes in phytochemicals during berry puree/juice processing was influenced by blanching and type of berries.

CONCLUSION: Phenolic contents and antioxidant activities of berries increased while total anthocyanins decreased during canning. Blanching prior to puree/juice processing improved the retention of phytochemicals in blueberries. Copyright © 2010 Society of Chemical Industry
Phototoxicity is not associated with photochemical tissue bonding of skin
Authors: Yao Min , Yaroslavsky Anna , Henry Frank P. , Redmond Robert W. , Kochevar Irene E.
Published: February 2010

Background and Objective

We have developed a light‐activated method called photochemical tissue bonding (PTB) for closing wounds using green light and a photosensitizing dye (Rose Bengal—RB) to initiate photochemical crosslinking of wound surface proteins. These studies were designed to determine whether RB causes phototoxicity during closure of skin incisions with PTB.

Study Design/Materials and Methods

RB phototoxicity was evaluated after sealing incisions in porcine skin ex vivo and rabbit skin in vivo using PTB (1 mM RB, 100 J/cm2, 532 nm, 0.3 or 0.5 W/cm2.) Dead cells were identified by pyknotic nuclei and eosinophilic cytoplasm on H&E‐stained sections. The influence on RB phototoxicity of penetration of RB into the wound wall (by confocal microscopy), RB concentration in the tissue (by extraction), and fluence of 532 nm reaching depths in skin (calculated from skin optical properties) were investigated.

Results

No significant differences were found in the percent dead cells in PTB‐treated and control incisions in porcine skin at 24 hours or in rabbit skin at 2 hours and 3 and 7 days after surgery. RB was retained in a ∼100 µm wide band next to the wound wall. The mean RB concentration within this band was 0.42±0.03 mM. Monte Carlo modeling of light distribution indicated that the fluence rate decreased from the subsurface peak to 0.5 W/cm2 in the mid‐dermis (∼350 µm.) In vitro RB phototoxicity to dermal fibroblasts yielded an LD50 of 0.50±0.09 J/cm2 when the cells contained 0.46 mM RB.

Conclusions

PTB does not cause phototoxicity when used to repair skin wounds even though the RB concentration and 532 nm fluence in the mid‐dermis during PTB are much greater than the LD50 for RB phototoxicity in vitro. These results indicate that phototoxicity is not a concern when using PTB for tissue repair. Lasers Surg. Med. 42:123–131, 2010. © 2009 Wiley‐Liss, Inc.
Ablative fractional lasers (CO2 and Er:YAG): A randomized controlled double‐blind split‐face trial of the treatment of peri‐orbital rhytides
Authors: Karsai Syrus , Czarnecka Agnieszka , Jünger Michael , Raulin Christian
Published: February 2010

Background and Objective

Ablative fractional lasers were introduced for treating facial rhytides in an attempt to achieve results comparable to traditional ablative resurfacing but with fewer side effects. However, there is conflicting evidence on how well this goal has generally been achieved as well as on the comparative value of fractional CO2 and Er:YAG lasers. The present study compares these modalities in a randomized controlled double‐blind split‐face study design.

Study Design/Materials and Methods

Twenty‐eight patients were enrolled and completed the entire study. Patients were randomly assigned to receive a single treatment on each side of the peri‐orbital region, one with a fractional CO2 and one with a fractional Er:YAG laser. The evaluation included the profilometric measurement of wrinkle depth, the Fitzpatrick wrinkle score (both before and 3 months after treatment) as well as the assessment of side effects and patient satisfaction (1, 3, 6 days and 3 months after treatment).

Results

Both modalities showed a roughly equivalent effect. Wrinkle depth and Fitzpatrick score were reduced by approximately 20% and 10%, respectively, with no appreciable difference between lasers. Side effects and discomfort were slightly more pronounced after Er:YAG treatment in the first few days, but in the later course there were more complaints following CO2 laser treatment. Patient satisfaction was fair and the majority of patients would have undergone the treatment again without a clear preference for either method.

Conclusions

According to the present study, a single ablative fractional treatment session has an appreciable yet limited effect on peri‐orbital rhytides. When fractional CO2 and Er:YAG lasers are used in such a manner that there are comparable post‐operative healing periods, comparable cosmetic improvement occurs. Multiple sessions may be required for full effect, which cancels out the proposed advantage of fractional methods, that is, fewer side effects and less down time. Lasers Surg. Med. 42:160–167, 2010. © 2009 Wiley‐Liss, Inc.
A split‐face study of intense pulsed light on photoaging skin in Chinese population
Authors: Li Yuan‐Hong , Wu Yan , Chen John Z.S. , Zhu Xia , Xu Yuan‐Yuan , Chen Jing , Dong Guang‐Hui , Gao Xing‐Hua , Chen Hong‐Duo
Published: February 2010

Background and Objectives

Intense pulsed light (IPL) is regarded as the gold standard of nonablative photorejuvenation. Yet there is still a need to observe its efficacy and safety on dark skin using a split‐face module.

Study Design/Materials and Methods

Twenty‐four Chinese women with photoaging were enrolled in this study. Patients were randomized to receive four IPL treatments at 3‐ to 4‐week intervals on one side of face, with the other side spared as control. Changes of photoaging were evaluated using a global evaluation, an overall self‐assessment, a Mexameter and a Corneometer. Skin biopsies were taken after four sessions of treatment on one side of face. The melanocyte density and the contents of melanin, collagen fibers, and elastic fibers were stained and used to evaluate the improvement on dyschromia and other signs of photoaging.

Results

The global scores of photoaging on treated side decreased significantly from 3.02 to 1.22, while it remained unchanged on the untreated side. Twenty‐one of 24 patients (87.5%) rated their improvement as excellent or good. The difference on the values of melanin index and erythema index on treated side were significantly larger than those on untreated side after the 1st session, the 4th session and at 3‐month follow‐up (P<0.05). The melanin contents were significantly decreased and the collagen fibers were obviously increased only on treated side (P<0.05). Adverse effects of treated side were limited to mild pain and transient erythema.

Conclusion

Using this split‐face module, IPL treatment is proved both clinically and histologically to be effective in treating photoaging skin in Chinese population. Adverse effects were minimal and acceptable. Lasers Surg. Med. 42:185–191, 2010. © 2010 Wiley‐Liss, Inc.
Laser‐mediated fixation of collagen‐based scaffolds to dermal wounds
Authors: Steinstraesser Lars , Wehner Martin , Trust Galina , Sorkin Michael , Bao Denxia , Hirsch Tobias , Sudhoff Holger , Daigeler Adrien , Stricker Ingo , Steinau Hans‐Ulrich , Jacobsen Frank
Published: February 2010

Background and Objective

Collagen scaffolds are popular for the reconstitution of dermal equivalents. Usually, these scaffolds are fixed with sutures or staples and in many cases these devices have to be removed in a second procedure. Laser‐mediated tissue welding in a wet environment is a potential alternative for collagen scaffold fixation and may be advantageous to suture, staple, and tissue glue fixation.

Materials and Methods

Welding was performed with a continuous‐wave diode laser system emitting radiation at a wavelength of 968 nm. Tensile strength after fixation to porcine skin and laser parameters were determined in vitro. In vivo, 24 excisional deep partial thickness wounds were created on flanks of two Goettingen mini pigs and covered with collagen scaffolds. These were randomized and fixated with either (1) staples, (2) fibrin glue, or (3) laser‐mediated welding. Tissue biopsies for histological analysis were periodically performed and analyzed for wound healing progression, epidermal thickness, and extracellular matrix formation.

Results

Biomechanical stability after laser welding was time dependent. A dwell time of up to 10 seconds led to a strong bonding with a tensile strength of more than 30 g. In vivo, the wound healing process was macroscopically comparable in all groups and showed no significant differences. Microscopic analysis determined a more progressed and quicker wound closure in both the laser and staples group compared to the fibrin glue fixated scaffold. Laser‐mediated fixation led to a significantly reduced epidermal thickness when compared with stapling or fibrin glue (P < 0.05).

Conclusions

Laser tissue welding is a feasible approach for temporary fixation of collagen scaffolds to the wound bed. It improves wound healing properties and may lead to faster wound healing and cosmetically better scarring. Laser tissue welding is thus a very interesting and promising alternative to currently established fixation methods in a single step, no touch procedure. Lasers Surg. Med. 42:141–149, 2010. © 2010 Wiley‐Liss, Inc.
Photodynamic photorejuvenation of the face with a combination of microneedling, red light, and broadband pulsed light
Authors: Clementoni Matteo Tretti , B‐Roscher Marc , Munavalli Girish S.
Published: February 2010

Background

High efficacy and safety, coupled with in‐office, short contact protocols have made photodynamic therapy (PDT) with aminolevulenic acid (ALA) for the treatment of actinic keratoses a mainstay option over the last decade. Clinical improvement in photoaged skin has also been reported to accompany PDT treatments. The study objective was to maximize epidermal penetration and subsequent activation of ALA for the treatment of photodamaged facial skin, utilizing a microneedle roller prior to incubation and combined irradiation with red light and broadband pulsed light in a single treatment.

Materials and Methods

A full‐face treatment of 21 patients was performed with 630 nm light and broadband pulsed light after multiple passes with a microneedle roller and 1‐hour ALA incubation. The primary endpoint was clinical improvement, scored during two separate live assessments by three physicians blinded to previous scores, using a 5‐point standardized photoaging scale. The secondary endpoint was evaluation of patient satisfaction based on a quartile scale comparing baseline to 6‐month post‐treatment photography.

Results

Statistically significant improvement was seen in the global photoaging scores, as well as sub‐components of the scale (fine lines, mottled pigmentation, sallowness, tactile roughness, and telangiectasias) at 3 months as compared with baseline live assessment, and at 6‐month live assessment compared with the 3 months. In addition, 90% of patients judged clinical improvement to be greater than 50% at 6 months compared to baseline photography.

Conclusion

Use of a microneedle roller to “pre‐treat” prior to application of ALA appears to be well tolerated and allows for even absorption and perhaps deeper penetration of ALA following a defined incubation period. Use of red light and broadband pulsed light allowed for deeper activation of ALA, potentially accounting for marked clinical improvement in photoaging. Lasers Surg. Med. 42:150–159, 2010. © 2010 Wiley‐Liss, Inc.
Tocopherol production in plant cell cultures
Authors: Caretto Sofia , Nisi Rossella , Paradiso Annalisa , De Gara Laura
Published: February 2010

Tocopherols, collectively known as vitamin E, are lipophilic antioxidants, essential dietary components for mammals and exclusively synthesized by photosynthetic organisms. Of the four forms (α, β, γ and δ), α‐tocopherol is the major vitamin E form present in green plant tissues, and has the highest vitamin E activity. Synthetic α‐tocopherol, being a racemic mixture of eight different stereoisomers, always results less effective than the natural form (R,R,R) α‐tocopherol. This raises interest in obtaining this molecule from natural sources, such as plant cell cultures. Plant cell and tissue cultures are able to produce and accumulate valuable metabolites that can be used as food additives, nutraceuticals and pharmaceuticals. Sunflower cell cultures, growing under heterotrophic conditions, were exploited to establish a suitable in vitro production system of natural α‐tocopherol. Optimization of culture conditions, precursor feeding and elicitor application were used to improve the tocopherol yields of these cultures. Furthermore, these cell cultures were useful to investigate the relationship between α‐tocopherol biosynthesis and photomixotrophic culture conditions, revealing the possibility to enhance tocopherol production by favouring sunflower cell photosynthetic properties. The modulation of α‐tocopherol levels in plant cell cultures can provide useful hints for a regulatory impact on tocopherol metabolism.
Effect of intermittent fasting with or without caloric restriction on prostate cancer growth and survival in SCID mice
Authors: Buschemeyer W. Cooper , Klink Joseph C. , Mavropoulos John C. , Poulton Susan H. , Demark‐Wahnefried Wendy , Hursting Stephen D. , Cohen Pinchas , Hwang David , Johnson Tracy L. , Freedland Stephen J.
Published: February 2010

INTRODUCTION

Caloric restriction (CR) delays cancer growth in animals, though translation to humans is difficult. We hypothesized intermittent fasting (i.e., intermittent extreme CR), may be better tolerated and prolong survival of prostate cancer (CaP) bearing mice.

METHODS

We conducted a pilot study by injecting 105 male individually‐housed SCID mice with LAPC‐4 cells. When tumors reached 200 mm3, 15 mice/group were randomized to one of seven diets and sacrificed when tumors reached 1,500 mm3: Group 1: ad libitum 7 days/week; Group 2: fasted 1 day/week and ad libitum 6 days/week; Group 3: fasted 1 day/week and fed 6 days/week via paired feeding to maintain isocaloric conditions to Group 1; Group 4: 14% CR 7 days/week; Group 5: fasted 2 days/week and ad libitum 5 days/week; Group 6: fasted 2 day/week and fed 5 days/week via paired feeding to maintain isocaloric conditions to Group 1; Group 7: 28% CR 7 days/week. Sera from mice at sacrifice were analyzed for IGF‐axis hormones.

RESULTS

There were no significant differences in survival among any groups. However, relative to Group 1, there were non‐significant trends for improved survival for Groups 3 (HR 0.65, P = 0.26), 5 (0.60, P = 0.18), 6 (HR 0.59, P = 0.16), and 7 (P = 0.59, P = 0.17). Relative to Group 1, body weights and IGF‐1 levels were significantly lower in Groups 6 and 7.

CONCLUSIONS

This exploratory study found non‐significant trends toward improved survival with some intermittent fasting regimens, in the absence of weight loss. Larger appropriately powered studies to detect modest, but clinically important differences are necessary to confirm these findings. Prostate 70: 1037–1043, 2010. © 2010 Wiley‐Liss, Inc.
Preparations of P‐ and N‐doped hydrogenated microcrystalline cubic silicon carbide films by VHF plasma enhanced chemical vapor deposition method for Si thin film solar cells
Authors: Yoshida Norimitsu , Terazawa Sho , Takeuchi Atsuteru , Yoneyama Nobutaka , Morino Tomo‐o , Jun Zhao , Natsuhara Hironori , Nonomura Shuichi
Published: February 2010

Nitrogen (N) and phosphorus (P) doped n‐type hydrogenated microcrystalline cubic silicon carbide (μc‐3C‐SiC:H) films have been prepared by VHF plasma enhanced chemical vapor deposition method for Si thin film solar cells. Ammonia (NH3) is employed as a N source. We show that the dark conductivity of the film reaches a value of about 10‐2 S/cm by doping N and P for a doping ratio of 0.8%. Further, it is found from x‐ray diffraction measurements that the crystalinity of N‐doped μc‐3C‐SiC:H films is better compared with that of P‐doped materials. NH3 seems to be one of useful materials for a N source of n‐type doping in μc‐3C‐SiC:H films. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of Cat‐CVD amorphous silicon film properties under high catalyzer temperature
Authors: Yen K. H. , Nishizaki S. , Ohdaira K. , Matsumura H. , Huang Y. T. , Zan H. W. , Tsai C. C.
Published: February 2010

In this study, we investigated the a‐Si films which were deposited by Cat‐CVD in the higher catalyzer temperature (Tcat) regime. We studied the influence of high Tcat on amorphous silicon (a‐Si:H) thin‐film properties. The information on a‐Si‐H bonding configuration was obtained by Fourier Transform Infrared Spectroscopy (FTIR). The film defect density was investigated by the electron spin resonance (ESR) as a function of Tcat, the distance between catalyzer and substrate (Dcs), and the deposition pressure (P). (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Image restoration for TV‐scan moving images acquired through a semiconductor backscattered electron detector
Authors: Oho Eisaku , Suzuki Kazuhiko
Published: February 2010

A semiconductor backscattered electron (BSE) detector has become popular in scanning electron microscopy session. However, detectors of semiconductor type have a serious disadvantage on the frequency characteristics. As a result, fast scan (e.g. TV‐scan) BSE image should be blurred remarkably. It is the purpose of this study to restore this degradation by using digital image processing technology. In order to improve it practically, we have to settle several problems, such as noise, undesirable processing artifacts, and ease of use. Image processing techniques in an impromptu manner like a conventional mask processing are unhelpful for this study, because a complicated degradation of output signal affects severely the phase response as well as the amplitude response of our SEM system. Hence, based on the characteristics of an SEM signal obtained from the semiconductor BSE detector, a proper inverse filter in Fourier domain is designed successfully. Finally, the inverse filter is converted to a special convolution mask, which is skillfully designed, and applied for TV‐scan moving BSE images. The improved BSE image is very effective in the work for finding important objects. SCANNING 31: 229–235, 2009. © 2010 Wiley Periodicals, Inc.
Plasma free metanephrines in healthy cats, cats with non-adrenal disease and a cat with suspected phaeochromocytoma
Authors: Wimpole Justin A. , Adagra Carl F.M. , Billson Mark F. , Pillai Dilo N. , Foster Darren J.
Published: February 2010

Phaeochromocytomas are catecholamine-secreting tumours of the adrenal glands and are rare in cats. Plasma metanephrine levels are widely considered the diagnostic test of choice for phaeochromocytoma in people but have not been investigated in cats. In this study plasma free normetanephrine and metanephrine levels were measured using high-pressure liquid chromatography in healthy cats, sick cats with non-adrenal disease and in a cat with a suspected phaeochromocytoma. Plasma normetanephrine was significantly higher in sick cats with non-adrenal disease compared to healthy cats ( P<0.05) and markedly higher in the cat with a suspected phaeochromocytoma when compared to either group. Plasma metanephrine was not significantly different in any of the groups. This study establishes a first-line guide reference range for plasma metanephrine and normetanephrine levels in healthy cats and cats with non-adrenal disease. These results provide rationale for further studies to establish the use of plasma normetanephrine levels as a potential diagnostic test for phaeochromocytoma in the cat.
V. S. Naipaul
Authors: Mustafa Fawzia
Published: February 2010

This introductory study offers a critical overview of the major works of V. S. Naipaul from 1950 to the present day. Professor Mustafa's main concern is with literary issues, but historical, political and cultural questions are also addressed, with comparative references to other postcolonial works. Paradoxically, a major segment of Naipaul's non-western, pro-decolonisation readership seized on negative elements in his thinking, while Western reaction to his ideas and themes led to set notions about Third-World society. Thus, his work has always been the object of radically divergent views, dependent on the perspective of the reader. In examining this issue, Mustafa introduces general debates about postcolonial literary production and its contemporary interrogation of narrative techniques, language, gender, race, and canon formulation.
Dynamics of the Standard Model
Authors: Donoghue John F. , Golowich Eugene , Holstein Barry R.
Published: February 2010

This book gives a detailed account of the Standard Model of particle physics, focussing on the techniques by which the model can produce information about real observed phenomena. It opens with a pedagogic account of the theory of the Standard Model. Introductions to the essential calculational techniques are included. The major part of the text is concerned with the use of the Standard Model in the calculation of physical properties of particles. Rigorous and reliable methods (radiative corrections and nonperturbative techniques based on symmetries and anomalies) are emphasized, but other useful models (such as the quark and Skyrme models) are also described. The strong and electroweak interactions are not treated as independent threads but rather are woven together into a unified phenomenological fabric. Many exercises and diagrams are included.
Topics in Varieties of Group Representations
Authors: Vovsi Samuel M.
Published: February 2010

This book is devoted to the theory of group representations, a young and promising area of modern algebra. It provides a detailed exposition of several central topics in the field, leading to the most current advances and developments. Much of the included material has never been available in book form before. It is intended for a broad audience of researchers and graduate students, working in abstract algebra and its many applications.