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71.
Environmental Biology of Fishes - Eel movement patterns have been frequently studied to learn about their movements within the fresh- and brackish waters of the same river before their spawning...  相似文献   
72.
Purpose

Bio-based recycling systems and agricultural production using recycled materials are often evaluated separately. This study performs an environmental and socio-economic life cycle assessment (LCA) of a food waste treatment and spinach farming system in Japan. The environmental and economic tradeoffs of introducing a recycling system and the net environmental benefit of the substitution of market fertilizer considering operation changes are also examined.

Methods

Three scenarios were developed and compared. In the conventional (CV) scenario, food waste is collected, incinerated, and disposed of in landfill, and the farmer uses market organic fertilizer. The on-site composting (OC) scenario processes food waste using an on-site garbage disposer and transports compost to a nearby spinach farmer. Food waste in the centralized composting (CC) scenario is transported to a centralized composting facility and resultant compost is sent to the farm. Primary data were obtained from field experiments and interviews. Non-greenhouse gas (GHG) emissions from the field and nitrogen leaching to water systems were simulated using the denitrification–decomposition (DNDC) model.

The environmental LCA targeted climate change, eutrophication, and waste landfill. An input–output analysis estimated socio-economic indicators, namely gross added value and employment inducement effect.

Results and discussion

The scenario with the lowest impact is the CC scenario. Climate change and eutrophication impacts are highest in the OC scenario and waste landfill impacts are most significant in the CV scenario. The weighted impact by LIME2 can be reduced by 47% in the CC scenario and 17% in the OC scenario due to the recycling of food waste instead of dumping in the landfill. The difference in socio-economic indicators between the scenarios was relatively small, although the CV scenario encouraged more employment. The substitution effect of composting, as well as the environmental impact reduction of replacing market organic fertilizer with compost, will result in 28.7% of the avoided impacts in GHG emissions.

Conclusions

Both composting scenarios are feasible from an environmental and socio-economic perspective when compared with conventional organic production, although there is a tradeoff between waste landfill and GHG emissions for the on-site composting system. However, the OC scenario needs to save electricity to improve its environmental competitiveness with the CV scenario. When considering the substitution effect of composting, it is recommended to take into account that agricultural operation also changes.

  相似文献   
73.
Photosynthetic organisms have diversified light-harvesting complexes (LHCs) to collect solar energy efficiently, leading to an acquisition of their ecological niches. Herein we report on biochemical and spectroscopic characterizations of fucoxanthin chlorophyll a/c-binding protein (FCP) complexes isolated from a marine pinguiophyte Glossomastix chrysoplasta. The pinguiophyte FCP showed one subunit band in SDS-PAGE and one protein-complex band with a molecular weight at around 66 kDa in clear-native PAGE. By HPLC analysis, the FCP possesses chlorophylls a and c, fucoxanthin, and violaxanthin. To clarify excitation-energy-relaxation processes in the FCP, we measured time-resolved fluorescence spectra at 77 K of the FCP adapted to pH 5.0, 6.5, and 8.0. Fluorescence curves measured at pH 5.0 and 8.0 showed shorter lifetime components compared with those at pH 6.5. The rapid decay components at pH 5.0 and 8.0 are unveiled by fluorescence decay-associated (FDA) spectra; fluorescence decays occur in the 270 and 160-ps FDA spectra only at pH 5.0 and 8.0, respectively. In addition, energy-transfer pathways with time constants of tens of picoseconds are altered under the basic pH condition but not the acidic pH condition. These findings provide novel insights into pH-dependent energy-transfer and energy-quenching machinery in not only FCP family but also photosynthetic LHCs.  相似文献   
74.
An assessment of the mechanical properties of trabecular bone is important in determining the fracture risk of human bones. Many uncertainty factors contribute to the dispersion of the estimated mechanical properties of trabecular bone. This study was undertaken in order to propose a computational scheme that will be able to predict the effective apparent elastic moduli of trabecular bone considering the uncertainties that are primarily caused by image-based modelling and trabecular stiffness orientation. The effect of image-based modelling which focused on the connectivity was also investigated. A stochastic multi-scale method using a first-order perturbation-based and asymptotic homogenisation theory was applied to formulate the stochastically apparent elastic properties of trabecular bone. The effective apparent elastic modulus was predicted with the introduction of a coefficient factor to represent the variation of bone characteristics due to inter-individual differences. The mean value of the predicted effective apparent Young's modulus in principal axis was found at approximately 460 MPa for respective 15.24% of bone volume fraction, and this is in good agreement with other experimental results. The proposed method may provide a reference for the reliable evaluation of the prediction of the apparent elastic properties of trabecular bone.  相似文献   
75.
Abstract

CXCR4 is both a chemokine receptor and an entry co-receptor for the T-cell line-adapted human immunodeficiency virus type 1 (HIV-1). To find a more efficacious therapeutic treatement of acquied immunodeficiency syndrome, we exmined the effects of antisense oligonucleotides on CXCR4 production. COS cells, stably expressing CXCR4 and CD4, were incubated with several kinds of oligonucleotides. Total human p24 antigen production was determined using an enzyme-linked immunosorbent assay system. An antisense phosphorothioate-modified oligonucleotide, complementary to the translation region of the CXCR4 mRNA, showed minimal inhibition of p24 antigen production at the high concentration of 2μM. On the other hand, the antisense phosphorothioate oligonucleotide, when used with transfection reagents, showed high efficiency at low concentrations, and confirmed the sequence-specific action. Interestingly, the oligonucleotide with the natual phosphodiester backbone, when used with the transfection reagents, also had high functional effects, comparable to the modified oligonucleotide. This defines the prerequisite criteria necessary for the design and the application of antisense oligonucleotides against HIV-1 in vivo.  相似文献   
76.
Abstract

A vinyl radical generated from a 6-chloro-9-(2-deoxy--d eryrhro-pent-l-enofuranosyl)-8-(2,2-dibromovinyl) purine effected cyclization either at the 1′-or at the 2′-position. The result is discussed in comparison with our previous study of the corresponding uracil derivative.  相似文献   
77.

Background

Marked accumulation of alveolar macrophages (AM) conferred by apoptosis resistance has been implicated in pathogenesis of chronic obstructive pulmonary disease (COPD). Apoptosis inhibitor of macrophage (AIM), has been shown to be produced by mature tissue macrophages and AIM demonstrates anti-apoptotic property against multiple apoptosis-inducing stimuli. Accordingly, we attempt to determine if AIM is expressed in AM and whether AIM is involved in the regulation of apoptosis in the setting of cigarette smoke extract (CSE) exposure.

Methods

Immunohistochemical evaluations of AIM were performed. Immunostaining was assessed by counting total and positively staining AM numbers in each case (n = 5 in control, n = 5 in non-COPD smoker, n = 5 in COPD). AM were isolated from bronchoalveolar lavage fluid (BALF). The changes of AIM expression levels in response to CSE exposure in AM were evaluated. Knock-down of anti-apoptotic Bcl-xL was mediated by siRNA transfection. U937 monocyte-macrophage cell line was used to explore the anti-apoptotic properties of AIM.

Results

The numbers of AM and AIM-positive AM were significantly increased in COPD lungs. AIM expression was demonstrated at both mRNA and protein levels in isolated AM, which was enhanced in response to CSE exposure. AIM significantly increased Bcl-xL expression levels in AM and Bcl-xL was involved in a part of anti-apoptotic mechanisms of AIM in U937 cells in the setting of CSE exposure.

Conclusions

These results suggest that AIM expression in association with cigarette smoking may be involved in accumulation of AM in COPD.  相似文献   
78.
Records of social interactions provide us with new sources of data for understanding how interaction patterns affect collective dynamics. Such human activity patterns are often bursty, i.e., they consist of short periods of intense activity followed by long periods of silence. This burstiness has been shown to affect spreading phenomena; it accelerates epidemic spreading in some cases and slows it down in other cases. We investigate a model of history-dependent contagion. In our model, repeated interactions between susceptible and infected individuals in a short period of time is needed for a susceptible individual to contract infection. We carry out numerical simulations on real temporal network data to find that bursty activity patterns facilitate epidemic spreading in our model.  相似文献   
79.
80.

Background/Aims

The Japanese National Hospital Organization evidence-based medicine (EBM) Study group for Adverse effects of Corticosteroid therapy (J-NHOSAC) is a Japanese hospital-based cohort study investigating the safety of the initial use of glucocorticoids (GCs) in patients with newly diagnosed autoimmune diseases. Using the J-NHOSAC registry, the purpose of this observational study is to analyse the rates, characteristics and associated risk factors of intracellular infections in patients with newly diagnosed autoimmune diseases who were initially treated with GCs.

Methodology/Principal Findings

A total 604 patients with newly diagnosed autoimmune diseases treated with GCs were enrolled in this registry between April 2007 and March 2009. Cox proportional-hazards regression was used to determine independent risk factors for serious intracellular infections with covariates including sex, age, co-morbidity, laboratory data, use of immunosuppressants and dose of GCs. Survival was analysed according to the Kaplan-Meier method and was assessed by the log-rank test. There were 127 serious infections, including 43 intracellular infections, during 1105.8 patient-years of follow-up. The 43 serious intracellular infections resulted in 8 deaths. After adjustment for covariates, diabetes (Odds ratio [OR]: 2.5, 95% confidence interval [95% CI] 1.1–5.9), lymphocytopenia (≦1000/μl, OR: 2.5, 95% CI 1.2–5.2) and use of high-dose (≧30 mg/day) GCs (OR: 2.4, 95% CI 1.1–5.3) increased the risk of intracellular infections. Survival curves showed lower intracellular infection-free survival rate in patients with diabetes, lymphocytopaenia and high-dose GCs treatments.

Conclusions/Significance

Patients with newly diagnosed autoimmune diseases were at high risk of developing intracellular infection during initial treatment with GCs. Our findings provide background data on the risk of intracellular infections of patients with autoimmune diseases. Clinicians showed remain vigilant for intracellular infections in patients with autoimmune diseases who are treated with GCs.  相似文献   
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