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41.
Decomposing road freight energy use in the United Kingdom   总被引:1,自引:0,他引:1  
Applying the techniques of decomposition analysis we estimate the relative contribution of ten variables (termed ‘key ratios’) plus GDP to the change in UK road freight energy use over the period 1989–2004 inclusive. The results are best interpreted as an estimate of the percentage growth in energy consumption that would have resulted from the change in the relevant factor (e.g. length of haul) had the other factors remained unchanged. The results demonstrate that the main factor contributing to the decoupling of UK road freight energy consumption from GDP was the decline in the value of domestically manufactured goods relative to GDP. Over the period 1989–2004 this largely offset the effect of increases in GDP on road freight energy consumption. While the decline in domestic manufacturing was to some extent displaced by increases in imports, the net effect of these supply factors, together with shifts in the commodity mix, has been to reduce UK road freight energy consumption by 30.1%. The net effect on global carbon dioxide (CO2) emissions is likely to be somewhat less beneficial, since many freight movements associated with the manufacture of imported goods have simply been displaced to other countries.  相似文献   
42.
In previous studies we demonstrated that the growth of human prostatic adenocarcinoma is associated with aberrant accumulation of transforming growth factor (TGF) beta1, a growth factor that has been shown to be a potent inhibitor of epithelial cell proliferation. We investigated the expression of TGF-beta receptor II (TGFbetaR-II) in benign prostate tissue and in prostate cancer using standard immunohistochemical techniques. Quantitation of immunopositivity for TGFbetaR-II was assessed on a visual analogue scale ranging from 0 (absence of staining) to 4+ (intensely positive staining). All of the benign glandular epithelia stained intensely, either 3+ or 4+, representative of the ubiquitous nature of TGFbetaR-II in normal tissue. Overall, staining was reduced in prostate cancer sections, and there was progressively diminished staining as the histological grade of the cancer increased (P < 0.01, Kruskal-Wallis test). This immunohistochemical study indicates that a decline in the levels of TGFbetaR-II is correlated with advancing histological aggressiveness of the cancer and suggests that aberrant TGFbetaR-II function may play a role in human prostate carcinogenesis.  相似文献   
43.
The authors propose a method for blind phase recovery based on finite alphabet properties (FAP) which can provide an accurate estimate even for a small subset of data. The phase and the data sequences are estimated simultaneously by using a maximum likelihood (ML) approach and an alternating projection technique  相似文献   
44.
In prostate cancer, mutation of the p53 tumor suppressor gene has been associated with locally advanced disease and hormone-resistant disease that is predominantly localized to bone. However, little is known regarding the status of the p53 gene in metastatic prostate cancer that has not been treated with hormonal manipulation. We evaluated formalin-fixed, paraffin-embedded malignant tissues from 86 patients with various stages of prostate cancer, including pathologically confined, locally advanced, and metastatic disease, to detect abnormal p53 nuclear protein accumulation using immunohistochemistry. No abnormal p53 immunostaining was detected in 18 patients with prostate cancer confined to the gland. Two tumors from 21 patients with locally advanced disease (extracapsular extension and/or seminal vesicle invasion) had abnormal nuclear p53 accumulation, and a mutation in exon 7 of the p53 gene was detected in tumor DNA from one patient using single-strand conformation polymorphism-direct sequencing analysis. Of the remaining 47 patients studied in whom tissues from the prostate gland and a metastatic site (44 lymph node, 2 bone, and 1 lung) were available, only 3 had received hormonal therapy prior to obtaining metastatic tissue. In four patients both primary and metastatic tumors demonstrated accumulation of p53 protein, whereas seven additional patients exhibited p53 accumulation only at the metastatic site. In three patients the metastatic tumors harbored missense single-base substitutions in exon 5, as detected using single-strand conformation polymorphism-direct sequencing. These results indicate that p53 abnormalities are associated with lymph node metastases derived from prostate cancer patients that had not undergone hormonal therapy.  相似文献   
45.
The distribution of surfactants in the different regions of the wool fibre has been studied by applying several novel fluorescent surfactants to wool under various conditions and studying sections of the treated fibres under the fluorescence microscope. The intercellular and cell remnant regions appear to be the preferred locations for these surfactants in the wool fibre, but various distributions can be obtained, depending on the length of the hydrocarbon chain of the surfactant and the conditions under which it is applied. The similarities in surface activity, sorption and extraction behaviour of the more typical surfactant sodium dodecyl sulphate and some of the fluorescent surfactants suggest that the former surfactant may have a similar distribution between the different regions of wool.  相似文献   
46.
We examined the spectrum of p53 mutations found in 40 UV-induced skin tumors of xeroderma pigmentosum group A gene (XPA)-deficient mice. p53 mutations were detected in 48% of the tumors. Nearly all of the mutations were induced at dipyrimidine sites. Ninety-three % of the mutations were G.C-->A.T transitions at dipyrimidine sites, including tandem transitions (CC-->TT), which are the hallmark of the UVB-induced mutation. Seventy-two % of the mutations at dipyrimidine sites could be ascribed to damage on the transcribed strand. In addition, no evident mutational hot spots were detected. This is in contrast to the UVB-induced skin tumors of normal mice, in which 92% of p53 mutations occurred as a result of DNA damage on the nontranscribed strand, and clear hot spots were observed. Thus, XPA-deficient mice showed significant mutation features that might be characteristic of the absence of nucleotide excision repair and may provide a good animal model for the analysis of the high incidence of skin cancer in xeroderma pigmentosum group A patients.  相似文献   
47.
Although prostatic cancer is often viewed as an androgen-dependent malignancy, a number of other hormones including 1alpha, 25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] are now recognized to modulate its growth and differentiated phenotype. Seven different continuous human prostatic carcinoma cell lines were examined for the presence of biologically active receptors for 1alpha,25(OH)2D3. All seven lines were found to contain mRNA for the vitamin D receptor using an RNase protection assay. Six of the seven cell lines were found to have high-affinity saturable binding sites for 1alpha,25(OH)2D3. The seventh line was found to contain vitamin D receptors by sucrose gradient analysis. All seven lines were found to express 24-hydroxylase activity by a HPLC assay that measures the conversion of 25-hydroxyvitamin D3 to 24,25-dihydroxyvitamin D3. 24-Hydroxylase activity was up-regulated in all seven cell lines by preincubation with 1alpha,25(OH)2D3. In the presence of fetal bovine serum, the growth of four of the seven cell lines was inhibited. In the majority of cell lines growth inhibition was related not only to the number of receptors per cell, but also in inverse proportion to the 24-hydroxylase activity of each cell line. The ubiquitous presence of vitamin D receptor and 24-hydroxylase activity in human prostatic carcinoma cells suggests new alternatives for the pharmacological treatment of advanced prostatic cancer and implies that chemoprevention strategies could also make use of this endocrine axis.  相似文献   
48.
49.
A groundwater activation model was developed for use in designing the accelerators at the Superconducting Super Collider Laboratory. This model is based on the concept of a 4-m-thick "activation zone" surrounding the accelerator enclosure, which contains over 99% of the soil activation caused by beam losses. Empirical shielding formulae based on computer simulations indicate that the soil activation in the activation zone decreases exponentially with distance from the tunnel enclosure. From this assumption, the average activation in the activation zone is derived. It is shown that the average activity concentration in the activation zone is equal to the activity concentration 1 m from the accelerator enclosure. The activation concentration in the water averaged over the volume of the activation zone is compared to the drinking water standards. The goal of this model is to meet the drinking water regulatory standards by averaging the activation in the activation zone. Groundwater activation concentrations have been calculated for the Super Collider utilizing experimental measurements of production cross sections and leachability factors. Comparison is made to the groundwater activation criterion for both routine and accidental beam losses.  相似文献   
50.

Free rides and observational advantages occur in visualizations when they reveal facts that must be inferred from an alternative representation. Understanding whether these concepts correspond to cognitive advantages is important: do they facilitate information extraction, saving the ‘deductive cost’ of making inferences? This paper presents the first evaluations of free rides and observational advantages in visualizations of sets compared to text. We found that, for Euler and linear diagrams, free rides and observational advantages yielded significant improvements in task performance. For Venn diagrams, whilst their observational advantages yielded significant performance benefits over text, this was not universally true for free rides. The consequences are two-fold: more research is needed to establish when free rides are beneficial, and the results suggest that observational advantages better explain the cognitive advantages of diagrams over text. A take-away message is that visualizations with observational advantages are likely to be cognitively advantageous over competing representations.

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