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A survey of corneal changes caused by daily wear silicone hydrogel contact lenses

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Journal of Innovative Optical health Sciences 2015年第6期8卷 92-100页

作者： Beata Kettesy Julianna Vardai Andras Berta Laszlo Modis jr. Adam Kemeny-Beke Department of Ophthalmology University of Debrecen Nagyerdei krt.98. H-4032 DebrecenHungary

The examination of the effects of second generation lotra filcon B silicone hydrogel(Sih)lenses on the cornea when worn for three years of daily *** and Methods:55 healthy patients were divided into two groups:current hydrogel contact lens wearers refitted with lotrafilcon B lenses(Group 1;28 patients)and neophyte contact lens wearers(Group 2;27 patients).Each patient's subjective eye comfort was measured with a self-administered *** corneas were analyzed using contact specular microscope to measure corneal thickness and the endothelium before the Sih lenses werefitted after four weeks,one month,six months,one year,two years,and three years of lens ***:Subjective complaints of patients in Group 1 were reduced;however patients in Group 2 experienced discomfort during the first two to four weeks of *** Group 1,objective examinations identified a decrease in endothelial cell *** Group 2,the endothelial cell density increased slightly in the first two years but decreased after three *** results indicate that lotra filcon B slows down the deleterious effects of contact *** coe±cient of variation significantly decreased after six months in Group 1(0.47 vs 0.44;p?0:049),whereas,in Group 2,the hexagonal cells improved significantly after one month(27.78 vs 28.25;p=0.025).Conclusion:Based on the subjects involved and the period of time under examination,it can be concluded that high-Dk Sih lenses support the physiological metabolism and functions of the cornea by improving oxygen provision.

关键词： Contact lens corneal endothelium silicone hydrogels specular microscopy cell density

Recovery of Collembola in pinus tabulaeformis plantations

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pedosphere 2017年第1期27卷 129-137页

作者： ChANG Liang WANG Baifeng LIU Xianghui Mac A.CALLAhAM jr. GE Feng State Key Laboratory of Integrated Management of pest and Rodents Institute of ZoologyChinese Academy of Sciences Northeast Institute of Geography and Agroecology Chinese Academy of Sciences USDA Forest ServiceSouthern Research StationCenter for Forest Disturbance Science

Large areas of forest plantations have been developed in China. It is important to evaluate the soil fauna in plantations and the conditions needed for their recovery in view of the large areas of plantations in China. Three pinus tabulaeformis forests, a 26-year-old plantation （p26） and a 45-year-old plantation （p45）, exposed to clear-cutting before plantation, and an 80 260-year-old natural forest （N260）, were chosen to study the effects of different forest ages/types on Collembola community in the lifter and soil layers during 2008 and 2009. Soil conditions in p26 and p45 were significantly deteriorated when compared to N260. A higher value of soil bulk density and lower values of soil organic matter, soil N, litter depth, soil ph, and soil water content were observed in p26 and p45. Totally, the same genera of Collembola tended to occur in the forests of all ages studied; however, the Collembola community structure was significantly impacted by the differences in forest age. Both in the litter and soil layers, the density and generic richness of the Collembola were the highest in N260 and the lowest in p26. Some collembolan groups were sensitive to soil conditions in particular forest ages. N260 was associated with relatively high abundance of plutomus collembolans and p45 with relatively high abundance of pseudofolsomia collembolans. The canonical correspondence analysis showed that the community structure of Collembola was mainly affected by forest age in both litter and soil layer. The ordination analysis of non-metric multidimensional scaling also found that the Collembola community did not recover to the level of natural forests in 26-year regeneration after clear-cutting. Even in 45-year regeneration after clear-cutting, the Collembola community only showed a slight recovery to the level of natural forests. Our results clearly showed that both Collembola community and soil conditions did not recover in 26- and 45-year regeneration after clear-cutting in p.

关键词： community structure forest age litter layer soil conditions soil fauna soil layer

SEN virus does not affect treatment response in hepatitis C virus coinfected patients but SEN virus response depends on SEN virus DNA concentration

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World Journal of Gastroenterology 2004年第13期10卷 1893-1897页

作者： Abdurrahman Sagin Ortwin adams OliverKirschberg AndreasErhardt Tobiasheintges Dieter hussinger Klinik fr Gastroenterologie Hepatologie und InfektiologieUniversittsklinikum DsseldorfMoorenstr 540225 DsseldorfGermany Institut fr Virologie der heinrich-heine-Universitt Dsseldorf Moorenstr 540225 DsseldorfGermany

AIM: To clarify the effect of SEN virus (SENV) infection on a combination therapy including interferon alfa (IFN-α) or pegylated-IFN with ribavirin in patients with chronic hepatitis and the effect of a combination therapy on ***: SENV DNA was determined by polymerase chain reaction in serum samples from 95 patients with chronic hepatitis C. Quantitative analysis was done for SENV h ***: Twenty-one (22%) of 95 patients were positive for SENV DNA. There was no difference in clinical and biochemical parameters between patients with hCV infection alone and coinfected patients. The sustained response rate for hCV clearance after combination therapy did not differ between patients with SENV (52%) and without SENV(50%, n.s.). SENV DNA was undetectable in 76% of the initially SENV positive patients at the end of follow-up. SENV h response to combination therapy was significantly correlated with SENV DNA level (p=-0.05).CONCLUSION: SENV infection had no influence on the hCV sustained response rate to the combination *** rate of SENV to the combination therapy depends on SENV DNA level.

关键词： Adult Antiviral Agents DNA Virus Infections DNA Viruses purification DNA, Viral Drug Therapy, Combination Female hepacivirus hepatitis C, Chronic humans Interferon Alfa-2a Interferon-alpha Male Middle Aged polyethylene Glycols prevalence RNA, Viral Ribavirin

Ocular biomechanical measurements on post- keratoplasty corneas using a Scheimpflug-based noncontact device

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International Journal of Ophthalmology(English edition) 2016年第2期9卷 235-238页

作者： Laszlo Modis jr. Ziad hassan Eszter Szalai Zsuzsanna Flasko Andras Berta Gabor Nemeth Department of Ophthalmology University of DebrecenDebrecen H-4032 Hungary Orbi-Dent health and Laser Center Debrecen H-4032Hungary

AIM： To analyse ocular biomechanical properties, central corneal thickness （CCT） and intraocular pressure （lOp） in post-keratoplasty eyes, as compared to normal subjects, with a new Scheimpflug-based technology. Moreover, biomechanical data were correlated with the size and age of the donor and recipient corneas. METhODS： Measurements were conducted on 46 eyes of 46 healthy patients without any corneal pathology （age： 53.83 ±20.8y） and 30 eyes of 28 patients after penetrating keratoplasty （age： 49.43 ±21.34y）. Ten biomechanical parameters, the CCT and lOp were recorded by corneal visualization Scheimpflug technology （CorVis ST） using high-speed Scheimpflug imaging. Keratometry values were also recorded using pentacam hR system. Scheimpflug measurements were performed after 43.41± 40.17mo （range： 11-128mo） after the keratoplasty and after 7.64±2.34mo （range： 5-14mo） of suture removal. RESULTS： Regarding the device-specific biomechanical parameters, the highest concavity time and radius values showed a significant decrease between these two groups （p=0.01 and p 〈0.001）. None of other biomechanical parameters disclosed a significant difference. The CCT showed a significant difference between post keratoplasty eyes as compared to normal subjects （p= 0.003） using the CorVis ST device. The lOp was within the normal range in both groups （p=0.84）. There were no significant relationships between the keratometric data, the size of the donor and recipient, age of the donor and recipient and biomechanical properties obtained by CorVis ST. CONCLUSION： The ocular biomechanics remain stable after penetrating keratoplasty according to the CorVis ST measurements. Only two from the ten device-specific parameters have importance in the follow-up period after penetrating keratoplasty.

关键词： corneal visualization Scheimpflugtechnology ocular biomechanics penetrating keratoplasty

Development of high-coercivity state in melt-spun Fe41pd41B8Si6p4 ribbons

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Rare Metals 2020年第1期39卷 76-83页

作者： Oksana Aleksandrovna Golovnia Nina Ivanovna Vlasova Aleksandr Gervasievich popov Vasiliy Semenovich Gaviko Vladimir Vladimirovich popov jr. Andrey Vladimirovich protasov Arti Kashyap M.N.Miheev Institute of Metal physics of Ural Branch of Russian Academy of Sciences EkaterinburgRussia620990 Institute of Natural Sciences and Mathematics Ural Federal UniversityEkaterinburgRussia620002 Israel Institute of Metals Technion R&D FoundationTechnion City3200003HaifaIsrael Indian Institute of Technology Mandi KamandMandiHP175005India

The phase transformation and magnetic hysteresis properties of melt-spun Fe41 pd41 B8 Si6 p4 ribbons subjected to the annealing at temperatures of 500-550℃were studied after holding for 0.1-60.0 h by transmission electron microscopy(TEM),X-ray diffraction(XRD)and thermomagnetic *** additions of p,B and Si to the Fepd alloy allowed us to achieve the coercivity of124 kA·m-1,which is 2.6 times higher than that of the melt-spun ribbons of the binary equiatomic Fepd *** high-coercivity Fe41pd41B8 Si6 p4 alloy is nanocrystalline and is composed of the ordered L10-phase grains approximately 40 nm in size and inclusions of the Fe2(p,B)and pd2(Si,B)*** coercivity kinetics is controlled by the phase transformation which can be divided into three stages:transformation from the bcc structure to nanosized regions of the fee and Fe2 p phases;transformation from the fee to L10 nanosized regions with somewhat different degrees of tetragonality and their ordering;and extensive growth of the weight fraction of L10 phase from the fee nanosized regions.p and B atoms occupy interstitial sites in the iron plane of L10 lattice,thus decreasing its Curie temperature(TC).

关键词： Fe-pd-p-B-Si Melt spinning L10 Nanostructured materials phase transformation Magnetic measurements

Single point and asymmetric incremental forming

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Advances in Manufacturing 2015年第4期3卷 253-262页

作者： J. Jeswiet D. adams M. Doolan T. McAnulty p. Gupta Department of Mechanical and Materials Engineering Queen's University Kingston ON Canada Faculty of Engineering and Information Technology Australian National University Canberra Australia

This paper presents an update on single point incremental forming （SpIF） of sheet metal since 2005. It includes a description of the process with new information on the maximum forming angle, Фmax, for 5052-h32. An indepth example of the successful design and production of parts is given for industry. This includes discussion on production times and surface roughness with details that will help designers. A general design guide for users of SpIF is provided. It is based upon experience gained in the last decade. In general, materials show a trend of decreasing formability with increasing initial thickness. It is shown that for thicker sheet metal, it is recommended using large spherical tools （12.7 mm or larger）, or a large fiat-ended tool. The fiat-ended tool provides the best combination of good formability and very low surface roughness. For aluminum, galvanized steel and stainless steel, it is recommended using a fiat-ended tool. Advances in multi-pass techniques and information on successful and useful numerical models which predict forming behaviour are included. Finally, there is a discussion on future work needed in SpIF.

关键词： Single point incremental forming (SpIF) Design guide for SpIF Advances in SpIF

The human malaria parasite genome is configured into thousands of coexpressed linear regulatory units

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Journal of Genetics and Genomics 2020年第9期47卷 513-521页

作者： Chengqi Wang Justin Gibbons Swamy R.Adapa Jenna Oberstaller Xiangyun Liao Min Zhang John h.adams Rays h.Y.Jiang Global and planetary health USF GenomicsCollege of Public HealthUniversity of South FloridaTampaFL 33612USA

The human malaria parasite plasmodium falciparum thrives in radically different host environments in mosquitoes and humans, with only a limited set of transcription factors. The nature of regulatory elements or their target genes in the p. falciparum genome remains elusive. here, we found that this eukaryotic parasite uses an efficient way to maximally use genetic and epigenetic regulation to form regulatory units(RUs) during blood infections. Genes located in the same RU tend to have the same pattern of expression over time and are associated with open chromatin along regulatory elements. To precisely define and quantify these RUs, a novel hidden Markov model was developed to capture the regulatory structure in a genome-wide fashion by integrating expression and epigenetic evidence. We successfully identified thousands of RUs and cross-validated with previous findings. We found more genes involved in red blood cell(RBC) invasion located in the same RU as the pf Ap2-I(Ap2-I) transcription factor, demonstrating that Ap2-I is responsible for regulating RBC invasion. Our study has provided a regulatory mechanism for a compact eukaryotic genome and offers new insights into the in vivo transcriptional regulation of the p. falciparum intraerythrocytic stage.

关键词： Gene regulation Regulatory units ATAC-Seq RNA-Seq hidden Markov Model Malaria plasmodium falciparum

Bioactivity of quaternary glass prepared from bentonite clay

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Journal of Advanced Ceramics 2016年第1期5卷 47-53页

作者： Luqman A.adams Enobong R.ESSIEN Department of Chemistry University of Lagos Nigeria Department of Chemical Sciences Bells University of Technology P.M.B 1015 Ota Ogun Nigeria

Alkoxysilane precursors are the most widely used silica source for sol–gel preparation of silicate-based bioactive glass. however, due to their high cost, alternative sources such as bentonite clay are desirable. In the present work, bentonite clay was reacted with sodium hydroxide (NaOh) to extract sodium metasilicate (Na2SiO3). The obtained Na2SiO3 was converted to gel which was then sintered at 950 ℃ for 3 h to give the bioactive glass in the quaternary composition SiO2–NaO–CaO–p2O5. The resulting glass was incubated in simulated body fluid (SBF) for 0–7 days to evaluate the bioactivity. Furthermore, glass samples were characterized before and after SBF study by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Results obtained showed the presence of Na2Ca2Si3O9 (combeite) crystal as the major crystalline phase and the formation of hydroxyapatite (hA) and hydroxycarbonated apatite (hCA) on the surface of the glass after immersion in SBF. The material showed potentials for application as scaffold in bone tissue repair.

关键词： bentonite clay bioactivity alkoxysilane hydroxyapatite (hA) bone repair

Automatic horizontal Road Design Information Extraction from Georeferenced polygonals： A Brazilian Federal highway Network Study

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Journal of Civil Engineering and Architecture 2015年第12期9卷 1513-1522页

作者： Alexandre h. Coelho Nataniel p. Borges jr. Nicolas p. Borges Marcos D. Gallo Amir M. Valente Department of Civil Engineering Federal University of Santa Catarina (UFSC) Florianopolis SC 88040-970 Brazil Transportation and Logistics Laboratory (Lab Trans) Federal University of Santa Catarina (UFSC) Florianopolis SC 88040-970Brazil

Road geometric design data are a vital input for diverse transportation studies. This information is usually obtained from the road design project. however, these are not always available and the as-built course of the road may diverge considerably from its projected one, rendering subsequent studies inaccurate or impossible. Moreover, the systematic acquisition of this data for the entire road network of a country or even a state represents a very challenging and laborious task. This study＇s goal was the extraction of geometric design data for the paved segments of the Brazilian federal highway network, containing more than 47,000 km of highways. It presents the details of the method＇s adoption process, the particularities of its application to the dataset and the obtained geometric design information. Additionally, it provides a first overview of the Brazilian federal highway network composition （curves and tangents） and geometry.

关键词： Curve identification information extraction geometric design polygonal segmentation road.