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Third Generation (third + generation)
Terms modified by Third Generation Selected AbstractsErythropoiesis-stimulating agents: development, detection and dangers,DRUG TESTING AND ANALYSIS, Issue 6 2009Stefan E. Franz Abstract Epoetin alfa, the first member of the family of erythropoiesis stimulating agents (ESAs), was introduced to the market in 1989. Since then development has progressed to epoetins of the third generation. Currently drugs that use alternative approaches to stimulate erythropoiesis are under development. Uptake of all available ESAs into doping has occurred rapidly after their introduction. A multitude of dangers to health are associated with the illicit use of these substances. Different approaches to detect ESAs in doping control have been developed to comply with the very diverse nature of the compounds used. Future developments in the field of ESA require the development of new techniques in doping analysis. This review gives an overview of the development of ESA and its detection methods as well as future developments. [Correction made here after initial online publication] Copyright © 2009 John Wiley & Sons, Ltd. [source] Seasonal population changes of five parasitoids attacking the scale insect Nipponaclerda biwakoensis on the common reed, with special reference to predation by wintering birdsENTOMOLOGICAL SCIENCE, Issue 4 2005Shuji KANEKO Abstract Seasonal changes in the abundance of five species of hymenopterous parasitoids (four species of Encyrtidae and one species of Eulophidae) attacking the scale insect Nipponaclerda biwakoensis on the common reed were investigated for 2 years in Lake Biwa, with special reference to predation by the reed bunting, Emberiza schoeniclus, during winter. The scales settled on reed shoot stems under sheath leaves, passing through three discrete generations per year. The abundance of adult female scales increased exponentially from July (first generation) to December (third generation). Adult female scales of the third generation overwintered on reed shoots. During winter, female scale abundance dramatically declined, whereas the number of predation marks made by reed buntings using their bills on reed sheath leaves increased. The generations of all five parasitoids were synchronized with the host scale generations, and the five parasitoids overwintered as larvae inside the scale bodies. The abundance of parasitized scales and parasitoid adults emerging from the scales also increased from July to December, but greatly decreased during winter. The overall parasitism rate of the female scales remained at relatively low levels (less than 40%) throughout the year, including before and after winter. A bird exclusion experiment revealed that the dramatic winter decrease of the abundance of the scale and its five parasitoids was due to intensive and non-selective predation by the buntings on unparasitized and parasitized scales. Additionally, the proportion of immature parasitoids removed by birds varied between the five parasitoid species. Thus, seasonal population changes of the five scale parasitoids are considerably affected by bird predation on overwintering immature parasitoids. [source] Toward an Integrative Model of Effective FOB SuccessionENTREPRENEURSHIP THEORY AND PRACTICE, Issue 4 2004Isabelle Le Breton-Miller Given that less than 10% of family owned businesses (FOBs) survive into the third generation, the issue of top executive succession has received a good deal of attention. Unfortunately, the literature on the topic is fragmented, as it deals with different parts of the elephant. This synthetic effort tries to put together the pieces to (1) derive a more encompassing model of what it takes for a succession to succeed, (2) determine the trends, consensus findings, as well as the gaps in our conceptual and empirical knowledge, and (3) suggest areas for further research. [source] Basal TSH levels compared with TRH-stimulated TSH levels to diagnose different degrees of TSH suppression: diagnostic and therapeutic impact of assay performanceEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2002M. Christ-Crain Abstract Background The estimated prevalence of endogenous subclinical hyperthyroidism varies from 4% to 6% and a basal thyroid stimulating hormone (TSH) level < 0·5 mU L,1 may be associated with increased mortality in subjects over 60 years of age who are not on thyroid medication. Exogenous TSH suppression is a mainstay in the treatment of thyroid cancer. Because of recent concerns about potential adverse effects, especially of endogenous TSH suppression on bone, the cardiovascular system and cognitive functions, subclinical hyperthyroidism obtained new clinical importance. We therefore re-evaluated the diagnostic value of basal and thyrotrop in TRH-stimulated serum TSH measurements using TSH assays with different sensitivities. Materials and methods A total of 805 oral and nasal TRH stimulation tests were performed on 409 ambulatory subjects with low basal serum TSH concentrations of less than 0·1 mIU L,1. Basal serum TSH was measured either using a second generation assay (functional sensitivity > 0·03 mIU L,1) or two third generation assays (functional sensitivity 0·01 mIU L,1 and 0·007 mU L,1, respectively). Serum TSH concentration was determined before and 3 h after oral administration of 40 mg of TRH and before and 30 min after nasal administration of 2 mg of TRH. Results In the oral testing group, the basal TSH levels measured by the different TSH assays were 0·06 ± 0·03, 0·04 ± 0·02 and 0·03 ± 0·02, respectively, whereas the peak TSH levels were 0·4 ± 0·6, 0·4 ± 0·6 and 0·3 ± 0·5 in the patients with subclinical hyperthyroidism. In overt hyperthyroidism, the basal TSH levels were 0·06 ± 0·02, 0·03 ± 0·02 and 0·03 ± 0·02, whereas the peak TSH levels were 0·19 ± 0·3, 0·16 ± 0·3 and 0·15 ± 0·2, respectively. Basal TSH values could discriminate between different degrees of TSH suppression if measured with a third generation assay (P < 0·001), but not with a second generation assay. There was only a weak correlation between basal TSH and peak TSH when measured by a second generation assay (n = 126; r = 0·3; P < 0·001) in contrast to the strong correlation found using the third generation assays (n = 128; r = 0·7; P < 0·001 and n = 69; r = 0·8; P < 0·001, respectively). Conclusions In view of the recent concerns about potential adverse effects in TSH suppression and based on our data, it is mandatory to select a TSH assay with a functional sensitivity of , 0·01 mIU L,1 for optimal titration of L-T4 suppressive therapy, especially in patients with thyroid cancer. If, however, only a second generation TSH assay is available, additional TRH testing allows a more careful titration of suppressive thyroxine therapy. [source] Solution-Processible Red Iridium Dendrimers based on Oligocarbazole Host Dendrons: Synthesis, Properties, and their Applications in Organic Light-Emitting Diodes,ADVANCED FUNCTIONAL MATERIALS, Issue 18 2008Junqiao Ding Abstract A series of novel red-emitting iridium dendrimers functionalized with oligocarbazole host dendrons up to the third generation (red-G3) have been synthesized by a convergent method, and their photophysical, electrochemical, and electroluminescent properties have been investigated. In addition to controlling the intermolecular interactions, oligocarbazole-based dendrons could also participate in the electrochemical and charge-transporting process. As a result, highly efficient electrophosphorescent devices can be fabricated by spin-coating from chlorobenzene solution in different device configurations. The maximum external quantum efficiency (EQE) based on the non-doped device configuration increases monotonically with increasing dendron generation. An EQE as high as 6.3% was obtained as for the third generation dendrimer red-G3, which is about 30 times higher than that of the prototype red-G0. Further optimization of the device configuration gave an EQE of 11.8% (13.0,cd A,1, 7.2,lm W,1) at 100,cd m,2 with CIE coordinates of (0.65, 0.35). The state-of-the-art performance indicated the potential of these oligocarbazole-based red iridium dendrimers as solution processible emissive materials for organic light-emitting diode applications. [source] District health systems in a neoliberal world: a review of five key policy areas,INTERNATIONAL JOURNAL OF HEALTH PLANNING AND MANAGEMENT, Issue S1 2003Malcolm Segall Abstract District health systems, comprising primary health care and first referral hospitals, are key to the delivery of basic health services in developing countries. They should be prioritized in resource allocation and in the building of management and service capacity. The relegation in the World Health Report 2000 of primary health care to a ,second generation' reform,to be superseded by third generation reforms with a market orientation,flows from an analysis that is historically flawed and ideologically biased. Primary health care has struggled against economic crisis and adjustment and a neoliberal ideology often averse to its principles. To ascribe failures of primary health care to a weakness in policy design, when the political economy has starved it of resources, is to blame the victim. Improvement in the working and living conditions of health workers is a precondition for the effective delivery of public health services. A multidimensional programme of health worker rehabilitation should be developed as the foundation for health service recovery. District health systems can and should be financed (at least mainly) from public funds. Although in certain situations user fees have improved the quality and increased the utilization of primary care services, direct charges deter health care use by the poor and can result in further impoverishment. Direct user fees should be replaced progressively by increased public finance and, where possible, by prepayment schemes based on principles of social health insurance with public subsidization. Priority setting should be driven mainly by the objective to achieve equity in health and wellbeing outcomes. Cost effectiveness should enter into the selection of treatments for people (productive efficiency), but not into the selection of people for treatment (allocative efficiency). Decentralization is likely to be advantageous in most health systems, although the exact form(s) should be selected with care and implementation should be phased in after adequate preparation. The public health service should usually play the lead provider role in district health systems, but non-government providers can be contracted if needed. There is little or no evidence to support proactive privatization, marketization or provider competition. Democratization of political and popular involvement in health enhances the benefits of decentralization and community participation. Integrated district health systems are the means by which specific health programmes can best be delivered in the context of overall health care needs. International assistance should address communicable disease control priorities in ways that strengthen local health systems and do not undermine them. The Global Fund to Fight AIDS, Tuberculosis and Malaria should not repeat the mistakes of the mass compaigns of past decades. In particular, it should not set programme targets that are driven by an international agenda and which are achievable only at the cost of an adverse impact on sustainable health systems. Above all the targets must not retard the development of the district health systems so badly needed by the rural poor. Copyright © 2003 John Wiley & Sons, Ltd. [source] Assimilation, Ethnic Competition, and Ethnic Identities of U.S.-Born Persons of Mexican OriginINTERNATIONAL MIGRATION REVIEW, Issue 3 2002Hiromi Ono Processes governing the ethnic identification of second and later generations of Mexican immigrant descendants are explored empirically using the Latino National Political Survey, 1989,1990. With multinomial logit regressions, I test hypotheses based on three contrasting perspectives, namely, that ethnic identification, or identification other than "American," arises directly from: a) cultural continuity and a lower level of assimilation; b) an experience of ethnic competition; and c) both processes. The results from the LNPS support the view that both processes are at work. For example, consistent with the presence of an assimilation process, the chance of "Mexican" identification (as opposed to "American" identification) declines to half in the third generation and to one tenth in the fourth and later generations, relative to the chance in the second generation. Consistent with the presence of an ethnic competition process, (perceived) experience of discrimination doubles the respondent's chance of "Mexican" identification. Also, a level rise in the darkness of skin color is associated with a 60 percent increase in the chance of Mexican identification. [source] Rhodium Complexed C2 -PAMAM Dendrimers Supported on Large Pore Davisil Silica as Catalysts for the Hydroformylation of OlefinsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 10 2005Abstract Polyamidoamine (PAMAM) dendrimers up to the third generation were grown for the first time on the surface of a large-pore (18,nm) Davisil silica support. The supported dendrimers of generations 0, 1, 2 and 3 were phosphinomethylated and complexed with rhodium. All the generations were found to be very active for the hydroformylation of olefins. The hydroformylation of 1-octene was accomplished with a turnover frequency of 1700,h,1 at 70,°C. The G(1) material was found to be the most active when the different generations were compared at 50% conversion at 70,°C [source] Response of multiple generations of beet armyworm, Spodoptera exigua (Hübner), feeding on transgenic Bt cottonJOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2009G. Wu Abstract Development, reproduction and food utilization of three successive generations of beet armyworm, Spodoptera exigua (Hübner), fed on transgenic and non-transgenic Bt cotton were examined. Significantly longer larval life-span and lower pupal weight were observed in three successive generations of S. exigua fed on transgenic Bt cotton compared with non-transgenic Bt cotton. Significantly higher survival rate and adult fecundity of S. exigua were found in three successive generations of S. exigua fed on transgenic Bt cotton compared with non-transgenic Bt cotton. The survival rate and adult fecundity of S. exigua were occurred significant increase in the third generation compared with the first generation after feeding on transgenic Bt cotton. Significantly lower consumption, frass and relative growth rate (RGR) were observed in three successive generations of S. exigua fed on transgenic Bt cotton compared with non-transgenic Bt cotton. Cotton variety significantly affected all indices of larval consumption and utilization in three successive generations of S. exigua, except for efficiency of conversion of ingested food. However, beet armyworm generation only significantly affected RGR of S. exigua. The results of this study indicated food quality on the diet-utilization efficiency of S. exigua was different along with beet armyworm generation. Measuring multigenerational development and food utilization of S. exigua at individual and population level in response to Bacillus thuringiensis (Bt) can provide a more meaningful evaluation of long-term population dynamics than experiments on a single generation. It is imperative to develop an appropriate multigenerational pest management tactic to monitor the field population dynamics of non-target pests (e.g., beet armyworm) in agricultural Bt cotton ecosystem. [source] Response of multiple generations of cotton bollworm Helicoverpa armigera Hübner, feeding on spring wheat, to elevated CO2JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2006G. Wu Abstract:, The growth, development and consumption of three successive generations of cotton bollworm, Helicoverpa armigera (Hübner), reared on milky grains of spring wheat grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers (OTCs) were examined. Decreases in protein, total amino acid, water and nitrogen content, and increases in total non-structure carbohydrates (TNCs) and ratio of TNC : nitrogen were found in wheat milky grains grown under elevated CO2 conditions. Changes in quality of wheat grains affected the growth, development and food utilization of H. armigera. Significantly longer larval lifespan for the third generation and lower pupal weight for all generations were observed in cotton bollworm fed on milky grains of spring wheat grown under elevated CO2 conditions. Bollworm fecundity was significantly decreased for the second and third generations under elevated CO2 levels. The consumption, frass per larva and relative consumption rate significantly increased in elevated CO2 compared with ambient CO2 conditions. However, the potential population consumption was significant reduced by elevated CO2 in the second and third generations. The results of this study indicate that elevated CO2 levels adversely affect grain quality, resulting in consistently increased consumption per larva for a longer period to produce less fecund bollworm through generations, suggesting that net damage of cotton bollworm on wheat will be less under elevated atmospheric CO2 levels because increased consumption is offset by slower development and reduced fecundity. [source] Antibacterial activity of dental composites containing zinc oxide nanoparticles,JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2010Berdan Aydin Sevinç Abstract The resin-based dental composites commonly used in restorations result in more plaque accumulation than other materials. Bacterial biofilm growth contributes to secondary caries and failure of resin-based dental composites. Methods to inhibit biofilm growth on dental composites have been sought for several decades. It is demonstrated here that zinc oxide nanoparticles (ZnO-NPs) blended at 10% (w/w) fraction into dental composites display antimicrobial activity and reduce growth of bacterial biofilms by roughly 80% for a single-species model dental biofilm. Antibacterial effectiveness of ZnO-NPs was assessed against Streptococcus sobrinus ATCC 27352 grown both planktonically and as biofilms on composites. Direct contact inhibition was observed by scanning electron microscopy and confocal laser scanning microscopy while biofilm formation was quantified by viable counts. An 80% reduction in bacterial counts was observed with 10% ZnO-NP-containing composites compared with their unmodified counterpart, indicating a statistically significant suppression of biofilm growth. Although, 20% of the bacterial population survived and could form a biofilm layer again, 10% ZnO-NP-containing composites maintained at least some inhibitory activity even after the third generation of biofilm growth. Microscopy demonstrated continuous biofilm formation for unmodified composites after 1-day growth, but only sparsely distributed biofilms formed on 10% ZnO-NP-containing composites. The minimum inhibitory concentration of ZnO-NPs suspended in S. sobrinus planktonic culture was 50 ,g mL,1. ZnO-NP-containing composites (10%) qualitatively showed less biofilm after 1-day-anaerobic growth of a three-species initial colonizer biofilm after being compared with unmodified composites, but did not significantly reduce growth after 3 days. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010. [source] Genetic variation in organisms with sexual and asexual reproductionJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2003B. O. Bengtsson Abstract The genetic variation in a partially asexual organism is investigated by two models suited for different time scales. Only selectively neutral variation is considered. Model 1 shows, by the use of a coalescence argument, that three sexually derived individuals per generation are sufficient to give a population the same pattern of allelic variation as found in fully sexually reproducing organisms. With less than one sexual event every third generation, the characteristic pattern expected for asexual organisms appear, with strong allelic divergence between the gene copies in individuals. At intermediary levels of sexuality, a complex situation reigns. The pair-wise allelic divergence under partial sexuality exceeds, however, always the corresponding value under full sexuality. These results apply to large populations with stable reproductive systems. In a more general framework, Model 2 shows that a small number of sexual individuals per generation is sufficient to make an apparently asexual population highly genotypically variable. The time scale in terms of generations needed to produce this effect is given by the population size and the inverse of the rate of sexuality. [source] Photophysical and self-assembly behavior of poly(amidoamine) dendrons with chromophore as scaffold: The effect of dendritic architectureJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 13 2008Bing-Bing Wang Abstract Two series of amphiphiles composed of hydrophilic poly(amidoamine) dendrons (from the first to the third generation) as the shell and hydrophobic aromatic chromophores (3,6-di(maleimidyl)-9-phenyl carbazole and 9-(4,-maleimidyl phenyl)-3-maleimidyl carbazole) as the central scaffold were synthesized. The effect of dendritic architecture on the photophysical properties and the self-assembly behavior of these amphiphiles were studied by UV,vis absorption spectroscopy, fluorescence spectroscopy, and transmission electron microscopy (TEM) measurements. Both the generation of dendritic shell and the location of dendrons at the chromophoric scaffold had great effect on the photophysical properties of these amphiphiles. In addition, different spherical aggregates were formed from these amphiphiles in the aqueous solution at different concentrations. Because of the combined effects of steric hindrance and architecture of dendritic shells, the amphiphiles from G2 dendron with central chromophore self-organized into ordered aggregates more readily than that from G1 and G3. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 4584,4593, 2008 [source] Population structure and paternal admixture landscape on present-day Mexican-Mestizos revealed by Y-STR haplotypesAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010J. Salazar-Flores Mestizos currently represent most of the Mexican population (>90%); they are defined as individuals born in the country having a Spanish-derived last name, with family antecedents of Mexican ancestors back at least to the third generation. Mestizos are result of 500 years of admixture mainly among Spaniards, Amerindians, and African slaves. Consequently, a complex genetic pattern has been generated throughout the country that has been scarcely studied from the paternal point of view. This fact is important, taking into account that gene flow toward the New World comprised largely males. We analyzed the population structure and paternal admixture of present-day Mexican-Mestizo populations based on Y-STRs. We genotyped at least 12 Y-STRs in DNA samples of 986 males from five states: Aguascalientes (n = 293); Jalisco (n = 185); Guanajuato (n = 168); Chiapas (n = 170); and Yucatán (n = 170). AmpF,STR Y-filer and Powerplex-Y® kits were used. Inclusion of North and Central Y-STR databases in the analyses allowed obtaining a Y-STR variability landscape from Mexico. Results confirmed the population differentiation gradient previously noted in Mestizos with SNPs and autosomal STRs throughout the Mexican territory: European ancestry increments to the Northwest and, correspondingly, Amerindian ancestry increments to the Center and Southeast. In addition, SAMOVA test and Autocorrelation Index for DNA Analysis autocorrelogram plot suggested preferential gene flow of males with neighboring populations in agreement with the isolation-by-distance model. Results are important for disease-risk studies (principally male-related) and for human identification purposes, because Y-STR databases are not available on the majority of Mexican-Mestizo populations. Am. J. Hum. Biol., 2010. © 2009 Wiley-Liss, Inc. [source] Networking as a Means to Strategy Change: The Case of Open Innovation in Mobile TelephonyTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 6 2007Koen Dittrich The purpose of this article is to investigate how innovation networks can be used to deal with a changing technological environment. This study combines different concepts related to research and development (R&D) collaboration strategies of large firms and applies these concepts to R&D alliance projects undertaken by Nokia Corporation in the period 1985,2002. The research methodology is a combination of in-depth semistructured interviews and a large-scale quantitative analysis of alliance agreements. For the empirical analysis a distinction is made between exploration and exploitation in innovation networks in terms of three different measures. As a first measure, the difference between exploration and exploitation strategies by means of the observed capabilities of the partners of the contracting firms is investigated. The second measure is related to partner turnover. The present article argues that in exploration networks partner turnover will be higher than in exploitation networks. As a third measure, the type of alliance contract will be taken; exploration networks will make use of flexible legal organizational structures, whereas exploitation alliances are associated with legal structures that enable long-term collaboration. The case of Nokia has illustrated the importance of strategic technology networks for strategic repositioning under conditions of change. Nokia followed an exploitation strategy in the development of the first two generations of mobile telephony and an exploration strategy in the development of technologies for the third generation. Such interfirm networks seem to offer flexibility, speed, innovation, and the ability to adjust smoothly to changing market conditions and new strategic opportunities. These two different strategies have led to distinctly different international innovation networks, have helped the company in becoming a world leader in the mobile phone industry, and have enabled it to sustain that position in a radically changed technological environment. This study also illustrates that Nokia effectively uses an open innovation strategy in the development of new products and services and in setting technology standards for current and future use of mobile communication applications. This article presents one of the first longitudinal studies, which describes the use of innovation networks as a means to adapt swiftly to changing market conditions and strategic change. This study contributes to the emerging, but still inconsistent, literature on explorative and exploitative learning by means of strategic technology networks. [source] Performance assessment of next-generation wireless mobile systemsBELL LABS TECHNICAL JOURNAL, Issue 4 2009Krishna Balachandran The deployment of third generation (3G) systems such as Universal Mobile Telecommunications System (UMTS) and code division multiple access (CDMA) 1X is now ubiquitous. Furthermore, several operators have already deployed evolved 3G systems such as high speed packet access (HSPA) and 1× evolution data optimized (1× EV-DO). These 3G and evolved 3G systems are based on spread spectrum technologies. Now the industry has begun to focus on next-generation wireless systems based on orthogonal frequency division multiplexing (OFDM) technology, flat-Internet Protocol (IP) architectures, and advanced multiple input-multiple output (MIMO) capabilities. These next-generation technologies, primarily are: 3rd Generation Partnership Project (3GPP)-based evolved UMTS terrestrial radio access network (EUTRAN), also called Long Term Evolution (LTE); 3rd Generation Partnership Project 2 (3GPP2)-based Ultra Mobile Broadband (UMB); and Institute of Electrical and Electronics Engineers (IEEE) 802. 16e-based Worldwide Interoperability for Microwave Access (WiMAX). These technologies are in the final specifications to initial deployment phases in selected markets. This paper provides an overview and performance analysis of these next-generation technologies based on their initial releases. Additionally, a comparative performance analysis of these technologies is also presented. © 2009 Alcatel-Lucent. [source] A Study on Modern High Effective Random Packings for Ethanol-Water RectificationCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2008S. Darakchiev Abstract Raschig Super-Ring is a modern and high-efficient packing used for intensification of absorption and distillation processes. The aim of this work is to characterize the efficiency of this packing applied to rectification of an important industrial system, ethanol-water, and to compare its efficiency to that of some random packings of the third generation as well as to the structured packing, HOLPACK, which is used in the ethanol production industry. The experiments were carried out in a column installation, 0.213,m in diameter with a packing height of 2.8,m. The column is heated by a number of electrical heaters (total power 45,kW), which can be switched gradually. Operation at total and partial reflux is possible. Eight types of random packings were studied: five types of Raschig Super-Ring, four metallic (with characteristic dimensions 0.5, 0.6, 0.7, and 1") and one of plastic material 0.6"; two types of packing IMTP and one plastic Ralu Flow. Some experiments were conducted at total reflux operation at vapor velocity, 0.253,0.936,m/s, and liquid superficial velocity, 4.44,·,10,4,1.63,·,10,3,m3/(m2s). Experiments at partial reflux were carried out at constant liquid superficial velocity and changeable vapor velocity as well as at constant vapor velocity and changeable liquid velocity. The results are presented as height of transfer unit, HTU, and height equivalent to a theoretical plate, HETP, as a function of the velocity of phases. [source] Development of lentiviral vectors for gene therapy for Usher syndrome type 1BACTA OPHTHALMOLOGICA, Issue 2007T HASHIMOTO Purpose: Usher 1B, one of the major subtypes of a combined blindness and deafness disease, is caused by mutations in the MYO7A gene, which encodes a large unconventional myosin expressed in the retinal pigment epithelium (RPE) and photoreceptor (PR) cells. This study aims at developing viral vectors expressing the wild type human MYO7A at an adequate level in order to rescue cellular phenotypes of MYO7A mutation. Methods: The full-length (7 kb) human MYO7A cDNA was cloned into the third generation, self-inactivating lentiviral vector under different promoters and enhancers. Human genomic 4-kb DNA fragment including exon 1 through 2 was cloned by PCR. Activities of different promoters and enhancers were tested by reporter assays using ARPE-19 cells. Previously identified Myo7a-null phenotypes in shaker-1 mouse were used to test the efficacy of various lentiviruses. Results: Lentiviral vectors could successfully transduce large genes (up to 7.6 kb) in vitro and in vivo for the purpose of gene therapy. Reporter assay indicated that regions with a suppressor activity and an enhancer activity existed within intron 1. The CMV promoter drove excessive MYO7A expression in the RPE, and thus caused cell death. A chimeric promoter that consists of partial CMV promoter with 160-bp MYO7A enhancer could direct moderate levels of gene expression in RPE and PR in vivo, and rescued a number of phenotypes in the mutant mice. Conclusions: These results illustrate the importance of regulating transgene expression levels in achieving therapeutic outcomes. They demonstrate the efficacy of lentivirus-mediated expression of the large MYO7A cDNA as a gene therapy strategy for correcting the MYO7A deficiency underlying Usher 1B. [source] Photo- and Redox-Active Dendritic Molecules with Soft, Layered NanostructuresCHEMISTRY - AN ASIAN JOURNAL, Issue 4 2006Yoshihiro Kikuzawa Abstract Molecules with one photoactive group (porphyrin) and multiple redox-active groups (ferrocenes) are described. The molecules are based on dendritic frameworks, with the ferrocenyl groups attached at the "internal" positions and the porphyrin attached at the focal point, leading to a characteristic layer architecture. Molecules of up to the third generation were synthesized and examined. The results of 1H,NMR spectroscopy and fluorescence quenching indicated that the ferrocenyl groups at the second layer approach the core porphyrin most closely, which is consistent with the results of molecular-dynamics simulations. The electrochemistry of the molecules was also examined in detail, and a new formula is proposed for the analysis of multiple-electron transfer in these "redox-pool" molecules. [source] Ellipsoid-shaped Carbosilane Dendrimers Modified with p -Nitroazobenzene Mesogens on the PeripheryCHINESE JOURNAL OF CHEMISTRY, Issue 2 2006Xin-De Tang Abstract Novel carbosilane liquid crystalline dendrimers based on 1,6-hexanediol were prepared. Using the precursors Gn -Cl (n=1,3) with SiCl bonds on the periphery as dendritic scaffolds and 4-[4-(6-hydroxyhexyloxy)phenylazo]-nitrobenzene as mesogenic group, a series of carbosilane liquid crystalline dendrimers from the first to the third generation were synthesized. These carbosilane liquid crystalline dendrimers showed smectic phase. [source] Dumbbell-shaped Carbosilane Dendrimers Based on 1,6-HexanediolCHINESE JOURNAL OF CHEMISTRY, Issue 1 2005Xin-De Tang Abstract Novel carbosilane dendrimers based on 1,6-hexanediol were prepared by divergent approach. Using 1,6-hexanediol-based diallyl ether as the core molecule, the dendrimers were prepared to the third generation with 54 allyl groups on the periphery by alternate hydrosilylation-allylation reactions. [source] Audit of antibiotic prescribing in two governmental teaching hospitals in IndonesiaCLINICAL MICROBIOLOGY AND INFECTION, Issue 7 2008U. Hadi Abstract This article estimates the magnitude and quality of antibiotic prescribing in Indonesian hospitals and aims to identify demographic, socio-economic, disease-related and healthcare-related determinants of use. An audit on antibiotic use of patients hospitalized for 5 days or more was conducted in two teaching hospitals (A and B) in Java. Data were collected by review of records on the day of discharge. The method was validated through concurrent data collection in Hospital A. Multivariate logistic regression analysis was performed to determine variables to explain antibiotic prescribing. Prescriptions were assessed by three reviewers using standardized criteria. A high proportion (84%) of 999 patients (499 in Hospital A and 500 in Hospital B) received an antibiotic. Prescriptions could be categorized as therapeutic (53%) or prophylactic (15%), but for 32% the indication was unclear. Aminopenicillins accounted for 54%, and cephalosporins (mostly third generation) for 17%. The average level of antibiotic use amounted to 39 DDD/100 patient-days. Validation revealed that 30% of the volume could be underestimated due to incompleteness of the records. Predictors of antibiotic use were diagnosis of infection, stay in surgical or paediatric departments, low-cost nursing care, and urban residence. Only 21% of prescriptions were considered to be definitely appropriate; 15% were inappropriate regarding choice, dosage or duration, and 42% of prescriptions, many for surgical prophylaxis and fever without diagnosis of infection, were deemed to be unnecessary. Agreement among assessors was low (kappa coefficients 0.13,0.14). Despite methodological limitations, recommendations could be made to address the need for improving diagnosis, treatment and drug delivery processes in this setting. [source] Third generation photovoltaics: Ultra-high conversion efficiency at low costPROGRESS IN PHOTOVOLTAICS: RESEARCH & APPLICATIONS, Issue 2 2001Martin A. GreenArticle first published online: 5 APR 200 Since the early days of terrestrial photovoltaics, a common perception has been that ,first generation' silicon wafer-based solar cells eventually would be replaced by a ,second generation' of lower cost thin-film technology, probably also involving a different semiconductor. Historically, cadmium sulphide, amorphous silicon, copper indium diselenide, cadmium telluride and now thin-film polycrystalline silicon have been regarded as key thin-film candidates. Any mature solar cell technology seems likely to evolve to the stage where costs are dominated by those of the constituent materials, be they silicon wafers or glass sheet. It is argued, therefore, that photovoltaics is likely to evolve, in its most mature form, to a ,third generation' of high-efficiency thin-film technology. By high efficiency, what is meant is energy conversion values double or triple the 15,20% range presently targeted, closer to the thermodynamic limit of 93%. Tandem cells are the best known of such high-efficiency approaches, where efficiency can be increased merely by adding more cells of different bandgap to a cell stack, at the expense of increased complexity and spectral sensitivity. However, a range of other more ,paralleled' approaches offer similar efficiency to an infinite stack of tandem cells. These options are reviewed together with possible approaches for practical implementation, likely to become more feasible with the evolution of materials technology over the next two decades. Copyright © 2001 John Wiley & Sons, Ltd. [source] Intergenerational acclimation in aphid overwinteringECOLOGICAL ENTOMOLOGY, Issue 1 2008S. J. POWELL Abstract 1.,When first instar nymphs and adults of the grain aphid Sitobion avenae (Fabricius) (Hemiptera: Aphidiae) were maintained in long-term cultures (>6 months) at 20 °C and 10 °C, the LT50 decreased from ,8 and ,8.8 °C to ,16.0 and ,13.5 °C, respectively. 2.,When aphids from the 20 °C culture were transferred to 10 °C, there was a progressive increase in cold tolerance through three successive generations. Transfer of newly moulted pre-reproductive adults reared at 10 °C for three generations back to 20 °C resulted in a rapid loss of cold hardiness in their nymphal offspring. 3.,In all generations reared at 10 °C, first born nymphs were more cold hardy than those born later in the birth sequence. The LT50 of nymphs produced on the first day of reproduction in the first, second and third generations maintained at 10 °C were ,14.8, ,17.0 and ,16.6 °C, respectively. Thereafter, nymphal cold hardiness decreased over the subsequent 14 days of reproduction in each generation at 10 °C with mean LT50 values of ,10.3, ,12.6 and ,14.8 °C, respectively. By contrast, the cold tolerance of first born nymphs of aphids reared continuously at 20 °C did not differ in comparison with later born siblings. The LT50 of adult aphids was also unaffected by ageing. 4.,The ecological relevance of these findings is discussed in relation to the overwintering survival of aphids such as S. avenae. [source] Response of multiple generations of cotton bollworm Helicoverpa armigera Hübner, feeding on spring wheat, to elevated CO2JOURNAL OF APPLIED ENTOMOLOGY, Issue 1 2006G. Wu Abstract:, The growth, development and consumption of three successive generations of cotton bollworm, Helicoverpa armigera (Hübner), reared on milky grains of spring wheat grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers (OTCs) were examined. Decreases in protein, total amino acid, water and nitrogen content, and increases in total non-structure carbohydrates (TNCs) and ratio of TNC : nitrogen were found in wheat milky grains grown under elevated CO2 conditions. Changes in quality of wheat grains affected the growth, development and food utilization of H. armigera. Significantly longer larval lifespan for the third generation and lower pupal weight for all generations were observed in cotton bollworm fed on milky grains of spring wheat grown under elevated CO2 conditions. Bollworm fecundity was significantly decreased for the second and third generations under elevated CO2 levels. The consumption, frass per larva and relative consumption rate significantly increased in elevated CO2 compared with ambient CO2 conditions. However, the potential population consumption was significant reduced by elevated CO2 in the second and third generations. The results of this study indicate that elevated CO2 levels adversely affect grain quality, resulting in consistently increased consumption per larva for a longer period to produce less fecund bollworm through generations, suggesting that net damage of cotton bollworm on wheat will be less under elevated atmospheric CO2 levels because increased consumption is offset by slower development and reduced fecundity. [source] A versatile preparation of azobenzene-dye functionalized colored polymer nanoparticles by surface modificationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 10 2008Caroline Cannizzo Abstract A series of stable and translucent colored nanolatex, that is, colloidal aqueous suspensions of dye-tagged polymer nanoparticles (NPs) in the 15- to 20-nm diameter range, have been prepared by covalent attachment of azobenzene chromophores to the surface of reactive NPs. Primary crosslinked NPs bearing chlorobenzyl groups were produced by microemulsion copolymerization of styrene and vinylbenzylchloride. Amine-functionalized NPs were obtained after a second functionalization step with polyamines (cyclam and polypropyleneimine dendrimers of first and third generations). Dye-doped particles were obtained by reacting pyridylazo-dimethylaminobenzene (PADA) with chlorobenzyl-NPs and by reacting amine-reactive dimethylaminoazobenzene dyes (DABsyl, DAB-ITC) as well as Disperse Red 1 acrylate with polyamine-coated NPs. Regardless the dye solubility, the grafting readily proceeded in aqueous suspensions at room temperature in the presence of a cationic surfactant without added solvent. Purple, red, and orange suspensions (maximum absorption around 550, 500, 430 nm), with dye loads ranging from 0.3 to 1.2 mmol/g, corresponding to 400,1800 azobenzene residues per NP, are obtained. The reported results indicate that functional polymer NPs, with remarkably accessible multiple anchoring sites, are useful building blocks. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3375,3386, 2008 [source] | |||||||||||||||||||||||||