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1.
Technological developments in municipal lighting are altering the spectral characteristics of artificially lit habitats. Little is yet known of the biological consequences of such changes, although a variety of animal behaviours are dependent on detecting the spectral signature of light reflected from objects. Using previously published wavelengths of peak visual pigment absorbance, we compared how four alternative street lamp technologies affect the visual abilities of 213 species of arachnid, insect, bird, reptile and mammal by producing different wavelength ranges of light to which they are visually sensitive. The proportion of the visually detectable region of the light spectrum emitted by each lamp was compared to provide an indication of how different technologies are likely to facilitate visually guided behaviours such as detecting objects in the environment. Compared to narrow spectrum lamps, broad spectrum technologies enable animals to detect objects that reflect light over more of the spectrum to which they are sensitive and, importantly, create greater disparities in this ability between major taxonomic groups. The introduction of broad spectrum street lamps could therefore alter the balance of species interactions in the artificially lit environment.  相似文献   

2.

Background

In visual psychophysics, precise display timing, particularly for brief stimulus presentations, is often required. The aim of this study was to systematically review the commonly applied methods for the computation of stimulus durations in psychophysical experiments and to contrast them with the true luminance signals of stimuli on computer displays.

Methodology/Principal Findings

In a first step, we systematically scanned the citation index Web of Science for studies with experiments with stimulus presentations for brief durations. Articles which appeared between 2003 and 2009 in three different journals were taken into account if they contained experiments with stimuli presented for less than 50 milliseconds. The 79 articles that matched these criteria were reviewed for their method of calculating stimulus durations. For those 75 studies where the method was either given or could be inferred, stimulus durations were calculated by the sum of frames (SOF) method. In a second step, we describe the luminance signal properties of the two monitor technologies which were used in the reviewed studies, namely cathode ray tube (CRT) and liquid crystal display (LCD) monitors. We show that SOF is inappropriate for brief stimulus presentations on both of these technologies. In extreme cases, SOF specifications and true stimulus durations are even unrelated. Furthermore, the luminance signals of the two monitor technologies are so fundamentally different that the duration of briefly presented stimuli cannot be calculated by a single method for both technologies. Statistics over stimulus durations given in the reviewed studies are discussed with respect to different duration calculation methods.

Conclusions/Significance

The SOF method for duration specification which was clearly dominating in the reviewed studies leads to serious misspecifications particularly for brief stimulus presentations. We strongly discourage its use for brief stimulus presentations on CRT and LCD monitors.  相似文献   

3.
Immunohistochemical analyses on local distributions of serum proteins in living mouse kidneys are usually difficult to examine with conventional preparation methods. By using our "in vivo cryotechnique" combined with freeze-substitution, we have checked immunolocalizations of the serum proteins in nephrons of bovine serum albumin (BSA)-overload mice, and compared them with those obtained by the conventional preparation methods. In two days of daily BSA-injected mice, the immunolocalization of BSA could be observed in Bowman's space and urinary tubules with their overt proteinuria, where another endogenous mouse albumin was similarly immunolocalized. The leakage of BSA and mouse albumin in Bowman's space and their reabsorption into proximal tubules were detected in 55% of nephrons, where no leakage of immunoglobulin G1 (IgG1) was detected. However, the leakage of IgG1, in addition to BSA and mouse albumin, was detected in the other nephrons. By carefully examining immunolocalizations of BSA and IgG1, they were obviously different from those obtained by the conventional preparation methods without normal blood circulation into the kidneys. The immunolocalizations of both BSA and mouse serum proteins could be directly analyzed with the "in vivo cryotechnique", suggesting that functional damage to glomerular filtration barriers are different at early stages of the BSA-overload mouse model, depending on each nephron of living mice.  相似文献   

4.
Cooke EF 《Bioethics》2003,17(1):32-58
New technologies in germ–line engineering have raised many questions about obligations to future generations. In this article, I focus on the importance of increasing freedom and the equality of freedom for present and future generations, because these two ideals are necessary for a just society and because they are most threatened by the wide–scale privatisation of GLE technologies. However, there are ambiguities in applying these ideals to the issue of genetic technologies. I argue that Amartya Sen's capability theory can be used as a framework to ensure freedom and equality in the use of GLE technology. Capability theory articulates the goal of equalising real freedom by bringing all people up to a threshold of basic human capabilities. Sen's capability theory can clarify the proper moral goal of GLE insofar as this technology could be used to bring people up to certain basic human capabilities, thereby increasing their real freedom. And by increasing the freedom of those who lack basic human capabilities, GLE can aid in decreasing the inequalities of freedom among classes of people.  相似文献   

5.
New technologies for the detection and therapy of early stage breast cancer are urgently needed. Pathological changes in breast might be reflected in proteomic patterns in serum. A proteomic tool was used to identify proteomic patterns in serum that distinguishes neoplastic from non-neoplastic disease within the breast. Preliminary results derived from the serum analysis from 54 unaffected women and 76 patients with breast cancer were analyzed by two-dimensional (2-D) electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry, HSP27 was found up-regulated while 14-3-3 sigma was down-regulated in the serum of breast cancer patients. The two protein biomarkers were then used to classify an independent set of 104 masked serum samples. The results showed that the protein pattern on 2-D gels can completely segregate the serum of breast cancer from non-cancer. The discriminatory pattern correctly identified all 69 breast cancer cases in the masked set. Of the 35 cases of non-malignant disease, 34 were recognized as non-cancer. These findings justify a prospective population-based assessment of proteomic technology as a screening or diagnostic tool for breast cancer in high-risk and general populations. These two protein biomarkers could also be used as targets for further study in drug design and breast cancer therapy.  相似文献   

6.
When droplets containing suspensions evaporate and dryout, they leave patterns which are the result of the composition of the liquid as well as the dynamics of evaporation. Exploiting these patterns for technological applications and biomedical purposes could represent a real opportunity. Patterning technologies could indeed exploit the phenomenon for a quick, simple and inexpensive technique for depositing nanolayers. For biomedical applications, the use of patterns formed from drying biological fluids as a means of disease diagnosis is an attractive idea. Indeed by studying, understanding and interpreting pattern formation from evaporating droplets this idea could lead to a simple and rapid technique for screening of various life threatening diseases. We present a review on this topic and point to the challenges that still to be overcome if this idea is to be fully exploited. In addition we present the results of an experimental investigation, presenting patterns formed by nanoparticles from evaporating droplets in different conditions.  相似文献   

7.
In recent years a fascinating evolution of different multicolor fluorescence in situ hybridization (FISH) technologies could be witnessed. The various approaches to cohybridize multiple DNA probes in different colors opened new avenues for FISH-based automated karyotyping or the simultaneous analysis of multiple defined regions within the genome. These developments had a remarkable impact on microscopy design and the usage of highly sensitive area imagers. In addition, they led to the introduction of new fluorochromes with appropriate filter combinations, refinements of hybridization protocols, novel probe sets, and innovative software for automated chromosome analysis. This paper attempts to summarize the various multicolor approaches and discusses the application of the individual technologies.  相似文献   

8.
Microalgae biomass is becoming an interesting raw material to produce biodiesel, where several approaches in the transesterification process have been applied such as different catalysts, different acyl acceptors, incorporation of co-solvents and the different operational conditions. However there are some drawbacks that must be solved before any industrial application could be intended. The main problems are related with the high water content of the biomass (over 80 %) and the several process steps involved in biodiesel production such as: drying, cell disruption, oils extraction, transesterification and biodiesel refining. In comparison to other alternatives, the use of direct transesterification could be a suitable alternative since cell disruption, lipids extraction and transesterification are carried out in one step, with a direct reaction of oil-bearing biomass to biodiesel. This process could be applied even using biomass with high water content, and its efficiency could be improved by the incorporation of promising technologies such as microwave or ultrasonication that can enhance the mass transfer rate between immiscible phases, simultaneously diminishing the reaction time. However, it is still necessary to decrease the costs of these technologies so they can be suitable alternatives in future industrial applications.  相似文献   

9.
Wang J  Wang L  Zhang D  Fan Y  Jia Z  Qin P  Yu J  Zheng S  Yang F 《Molecular biology reports》2012,39(5):5095-5104
Wilms tumor is the most common pediatric tumor of the kidney. Previous studies have identified several serum biomarkers for Wilms tumor; however, they lack sufficient specificity and may not adequately distinguish Wilms tumor from confounding conditions. To date, no specific protein biomarker has been confirmed for this pediatric tumor. To identify novel serum biomarkers for Wilms tumor, we used proteomic technologies to perform protein profiling of serum samples from pre-surgery and post-surgery patients with Wilms tumor and healthy controls. Some common systemic inflammatory factors were included to control for systemic inflammation. By comparing protein peaks among the three groups of sera, we identified two peaks (11,526 and 4,756 Da) showing significant differential expression not only between pre-surgery and control sera but also between pre-surgery and post-surgery sera. These two peaks were identified as serum amyloid A1 (SAA1) and apolipoprotein C-III (APO C-III). Western blot analysis confirmed that both proteins were expressed at higher levels in pre-surgery sera than in post-surgery and control sera. Using the method of leave-1-out for cross detection, we demonstrate that detection of these two candidate biomarkers had high sensitivity and specificity in discriminating pre-surgery sera from post-surgery and normal control sera. Taken together, these findings suggest that SAA1 and APO C-III are two potential biomarkers for Wilms tumor.  相似文献   

10.
New reproductive technologies include sexed sperm and embryo-based technologies. The technology of sperm sexing, for various reasons, is not available in New Zealand and its use has not been modelled. Embryo technologies are however already in use on a limited scale and various scenarios for their use in both the dairy and beef industries in New Zealand have been modelled. This review briefly discusses the various technologies available and some of their potential strengths and weaknesses. In the dairy industry, modelling has been used to simulate the production of breeding bulls for large breeding companies and the production of replacement heifers in dairy herds. For the beef industry, similar modelling has been carried out to determine the opportunities for more efficient beef production.All the models confirmed that at current levels of performance, embryo-based reproductive technologies are usually not profitable in New Zealand except in niche market situations where the returns from the resulting offspring are significantly greater than can be obtained from natural mating or artificial insemination (AI) reproduction systems. This is confirmed by the low uptake of these technologies in this country to date. Even if performance lifts to levels similar to AI, profitability is likely to occur only if the costs of pregnancies to embryo-based reproductive technologies can occur at prices less than two to four times greater than AI or natural mating. This break-even requirement depends on the returns that can be achieved and the advantages that can be captured by the technology over and above those available from AI or natural mating. Two new uses for reproductive technologies in dairy cattle could be the proliferation of novel or rare genotypes from gene discovery programs and improving the female reproductive rate for optimal marker assisted selection. In both these uses the technology is not at present competing with AI or natural mating. The challenge exists therefore for the biological scientists to satisfy these requirements, coupled with the ethical and human factors involved in the introduction of any new technology.Potential end users of the technologies have been surveyed. They are quite positive about the technologies provided they can use them profitably and are keen to obtain more information about them.  相似文献   

11.
Serum taken from mice a few hours after injection of endotoxin is a potent source of a stimulator of in vitro myelopoiesis. By means of dose-response studies, the biological activity of this material was compared to that of a colony stimulating factor (CSF) from pregnant mouse uteri. Postendotoxin serum appears to contain two different activities: a stimulating activity which may be identical to CSF and an activity which augments the action of CSF. The separate nature of the two activities is demonstrated by differences in the rate at which they are diluted out and by differences in the time at which they are maximally present after endotoxin administration. It is therefore concluded that the colony-stimulating properties of postendotoxin serum are not due solely to CSF present in the serum.  相似文献   

12.
Rat liver ornithine decarboxylase induced by injection of thioacetamide has been separated into at least two fractions by covalent chromatography on an activated thiol-Sepharose 4B column. The two major fractions could be distinguished by ion exchange chromatography and electrophoresis on acrylamide gels. In addition, the two forms displayed different Km values for ornithine. Although the two forms are separable, they display identical antigenic properties, pH optima, and they appear to be the same molecular size. The biological significance or the relationship between multiple forms of ornithine decarboxylase is not understood.  相似文献   

13.
In pigs, many production traits are known to vary among breeds or lines. These traits can be considered end phenotypes or external traits as they are the final results of complex biological interactions and processes whose fine biological mechanisms are still largely unknown. This study was designed to compare plasma and serum metabolomic profiles between animals of two heavy pig breeds (12 Italian Large White and 12 Italian Duroc), testing indirectly the hypothesis that different genetic backgrounds might be the determining factors of differences observed on the level of metabolites in the analyzed biofluids between breeds. We used a targeted metabolomic approach based on mass spectrometric detection of about 180 metabolites and applied a statistical validation pipeline to identify differences in the metabolomic profiles of the two heavy pig breeds. Blood samples were collected after jugulation at the slaughterhouse and prepared for metabolomics analysis that was carried out using the Biocrates AbsoluteIDQ p180 Kit, covering five different biochemical classes: glycerophospholipids, amino acids, biogenic amines, hexoses and acylcarnitines. A statistical pipeline that included the selection of the most relevant metabolites differentiating the two breeds by sparse Partial Least Squares Discriminant Analysis (sPLS-DA) was coupled with a stability test and significance test determined with leave one out and permutation procedures. sPLS-DA plots clearly separated the pigs of the two investigated breeds. A few metabolites (a total of five metabolites considering the two biofluids) involved in key metabolic pathways largely contributed to these differences between breeds. In particular, a higher level of the sphingomyelins SM (OH) C14:1 (both in plasma and serum), SM (OH) C16:1 (in serum) and SM C16:0 (in serum) were observed in Italian Duroc than in Italian Large White pigs and the inverse was for the biogenic amine kynurenine (in plasma). The level of another biogenic amine (acetylornithine) was higher in Italian Large White than in Italian Duroc pigs in both analysed biofluids. These results provided biomarkers that could be important to understand the biological differences between these two heavy pig breeds. In particular, according to the functional role played by sphingomyelins in obesity-induced inflammatory responses, it could be possible to speculate that a higher level of sphingomyelins in Italian Duroc might be related to the higher interrmuscular fat deposition of this breed compared with the Italian Large White. Additional studies will be needed to evaluate the relevance of these biomarkers for practical applications in pig breeding and nutrition.  相似文献   

14.
Levels of testosterone (T) and LH in the peripheral serum of male and female rabbits were measured and compared following coitus. Blood was collected by heart puncture from restrained, unanesthetized animals of both sexes. In male rabbits, basal serum T levels were highly variable, ranging from 131 to 12,149 pg/ml, and if low preceding coitus they tended to rise; whereas, if high, they usually dropped as they did in nonmated males subjected to repeated heart punctures. In contrast, basal serum LH levels in males were quite constant (mean +/- SE, 1993 +/- 152 pg/ml) and were not significantly altered after coitus unless blood T levels had been drastically lowered by two priming doses of estradiol benzoate. In intact does, on the other hand, copulation which resulted in ovulation induced an approximately 20-fold increase in serum LH concentration which was sustained for about 4 hr. Postcoital elevations in serum LH also occurred in estrogen-primed intact and estrogen-primed ovariectomized does. Under the conditions of our experiments, the parallel elevations in serum LH and T observed postcoitally in the female rabbit could not be demonstrated in the male.  相似文献   

15.
Xiang Y  Ma B  Yu HM  Li XJ 《Life sciences》2004,75(11):1277-1285
The aim of the present research is to analyze the proteome of neoplasm serum before and after treated with acetazolamide (20, 40, 80 mg kg(-1) d(-1) for 3 days p.o.). The Lewis lung carcinoma mice were used and carried out a comprehensive proteomic analysis by using the technologies of high-resolution two-dimensional polyacrylamide gel electrophoresis (2D PAGE) and mass spectrometry (MS). The results showed that the acetazolamide could dramatically reduce the lung metastasis and primary tumor growth. Its most potent inhibition rate on lung metastases was reach to 77.7% at the dose of 80 mg kg(-1) d(-1). The two dimension electrophoresis and software analysis reveal 393 protein spots in control gel, 385 protein spots were detected in treated gel and matched 209 protein spots with control gel, indicating that intensive changes had occurred during the process of treatment. Two obviously different spots were cut off from gel and for the peptide mass fingerprinting. Data base searching showed the two proteins' peptide much more mach with Histone H2B fragment and Ubc-like protein CROC1 fragment. The results suggest that acetazolamide has a strong anti-tumor and anti-metastasis effect on Lewis-lung-carcinoma. The mechanism may be related to its regulation on plenty of proteins, in particular, on upregulation of H2B and CROC-1 expression of postreplicational DNA repair related protein in serum.  相似文献   

16.
Chen W  Feng Y  Gong R  Zhu Z  Wang Y  Zhao Q  Dimitrov DS 《Journal of virology》2011,85(18):9395-9405
Soluble forms of the HIV-1 receptor CD4 (sCD4) have been extensively characterized for more than 2 decades as promising inhibitors and components of vaccine immunogens. However, they were mostly based on the first two CD4 domains (D1D2), and numerous attempts to develop functional, high-affinity, stable soluble one-domain sCD4 (D1) have not been successful because of the strong interactions between the two domains. We have hypothesized that combining the power of structure-based design with sequential panning of large D1 mutant libraries against different HIV-1 envelope glycoproteins (Envs) and screening for soluble mutants could not only help solve the fundamental stability problem of isolated D1, but may also allow improvement of D1 affinity while preserving its cross-reactivity. By using this strategy, we identified two stable monomeric D1 mutants, mD1.1 and mD1.2, which were significantly more soluble and bound Env gp120s more strongly (50-fold) than D1D2, neutralized a panel of HIV-1 primary isolates from different clades more potently than D1D2, induced conformational changes in gp120, and sensitized HIV-1 for neutralization by CD4-induced antibodies. mD1.1 and mD1.2 exhibited much lower binding to human blood cell lines than D1D2; moreover, they preserved a β-strand secondary structure and stability against thermally induced unfolding, trypsin digestion, and degradation by human serum. Because of their superior properties, mD1.1 and mD1.2 could be potentially useful as candidate therapeutics, components of vaccine immunogens, and research reagents for exploration of HIV-1 entry and immune responses. Our approach could be applied to other cases where soluble isolated protein domains are needed.  相似文献   

17.

Purpose

Technologies can contribute to sustainable development (e.g., improving living conditions) and at the same time cause sustainability problems (e.g., emissions). Decisions on alternative technologies should thus ideally be based on the principle to minimize the latter. Analyzing environmental, economic, and social aspects related to technologies supports decisions by identifying the “more sustainable” technology. This paper focuses on social issues. First, it discusses the applicability of the social life cycle assessment (SLCA) guidelines for a comparative technology analysis, taking the example of two case studies in developing countries. Indicating technologies as “sustainable” also means that they are indeed operated over the expected lifetime, which, in development projects, is often not guaranteed. Consequently, social aspects related to implementation conditions should be considered in an SLCA study as well. Thus, a second focus is laid on identifying appropriate indicators to address these aspects.

Methods

First, the SLCA guidelines were examined with regard to applying this product-related approach to two real case studies (analysis of technologies/plants for water supply and for decentralized fuel production) for a comparative technology analysis. Suitable indicators are proposed. To address the second focus, a literature research on technology assessment and implementation in developing countries was conducted. Moreover, socioeconomic studies in the investigation areas of the case studies were consulted. Based on this, indicators addressing implementation conditions were identified from the SLCA guidelines and additional literature.

Results and discussion

The study shows social issues and indicators found in the SLCA guidelines and considered suitable for a comparative technology analysis in the case studies. However, for a sustainability assessment of technologies, especially in developing countries, further indicators are required to address technology implementation conditions. A set of additional social indicators like reported trust in institutions or fluctuation of personnel is proposed. Though these indicators were derived based on specific case studies, they can also be suggested to other technologies and are not necessarily limited to developing countries.

Conclusions

The study pointed out that an application of the SLCA guidelines considering the whole life cycle was not (yet) feasible for the case studies considered. This is mainly due to the lack of data. Regarding technology implementation, it was examined which indicators are available in this SLCA approach and which could additionally be integrated and applied. This is relevant as a potential contribution of technologies to sustainable development can only be achieved when the technologies are successfully implemented.  相似文献   

18.
Sexual dimorphism is evident in many quantitative genetic traits, and there has been much speculation on the evolution of primate sexual dimorphism. Morphological characters have been the main focus of attention, while sexual dimorphism in physiological quantitative traits has been neglected. In either case, the genetic basis of primate sexual dimorphism has received little attention. This study characterizes genotype by sex (GxS) interactions in two physiological traits, serum apolipoprotein AI (apo AI) and high density lipoprotein cholesterol (HDL-C) concentrations, in baboons fed two different diets, a basal diet and a high cholesterol saturated fat (HCSF) diet. A GxS interaction effect on a trait indicates a heritable component of male/female differences in that trait. Using maximum likelihood methods, eight different quantitative genetic models were evaluated. Significant GxS interactions were found for serum apo AI and HDL-C concentrations on the basal diet. GxS interactions were suggested for serum apo AI and HDL-C concentrations on the HCSF diet, but they were not statistically significant. These results reveal that sexual dimorphisms in serum apo AI and HDL-C concentrations in baboons are heritable, with heritabilities that are influenced by diet. © 1992 Wiley-Liss, Inc.  相似文献   

19.
Two electrophoretically homogeneous immunoglobulins were detected in the serum of a patient with multiple myeloma. The heavy chains were of different classes (gamma 1 and gamma 2). The light chains of both were kappa, but had different electrophoretic mobilities on polyacrylamide gels. Amino acid sequence analysis, carbohydrate determinations, and biosynthetic experiments indicated that the difference seen in their electrophoretic mobility was due to the glycosylation of one but not the other kappa-chain. The primary structure of both chains demonstrated that they both used a V kappa 1 and a J kappa 2 gene segment and the same C kappa allele, Km(1,2), and that both contained the same junctional three amino acid deletion. However, they varied by 19 amino acids in the first 94 amino terminal residues encoded for by the V kappa gene, with some of the substitutions requiring two base changes in the appropriate codons. Moreover, the malignant "clones" producing the two proteins differed in their responses to chemotherapy. These data indicate that, although the two clones producing the serum proteins were different at the time of study, they may have arisen from the same precursor clone.  相似文献   

20.
The increasing production of food waste worldwide and new international regulations call for the development of new technologies to treat this biowaste. Anaerobic processes are able to treat efficiently organic wastes, producing at the same time different value-added compounds. In addition, due to the lower costs and environmental impacts associated with these processes when compared to other options, they are among the most promising technologies for food waste treatment. This article reviews the state-of-the-art dealing with treatment of food waste by anaerobic processes, with emphasis on the most recent research carried out. The different processes that are assessed are anaerobic digestion for methane production, anaerobic fermentation for hydrogen and/or volatile fatty acids production and 2-stage systems. The primary issues associated with each alternative are presented, paying special attention to accumulation of ammonia and volatile fatty acids in the reactor. In addition, the latest developments to overcome the complications of each system are also described, focusing on how they improve its stability and performance. Moreover, the relevant economic and environmental research has also been reviewed, including several life cycle analyses that compare anaerobic processes with other technologies used for food waste treatment. Different case studies are also presented. Finally, recommendations for future research for the anaerobic processes studied and options for process integration are discussed. Moving towards the idea of a circular economy, a potential biorefinery for food waste valorization is also proposed.  相似文献   

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