Enhancing forest carbon sequestration in China: toward an integration of scientific and socio-economic perspectives

This article serves as an introduction to this special issue, "China's Forest Carbon Sequestration", representing major results of a project sponsored by the Canadian International Development Agency and the Chinese Academy of Sciences. China occupies a pivotal position globally as a principle emitter of carbon dioxide, as host to some of the world's largest reforestation efforts, and as a key player in international negotiations aimed at reducing global greenhouse gas emission. The goals of this project are to develop remote sensing approaches for quantifying forest carbon balance in China in a transparent manner, and information and tools to support land-use decisions for enhanced carbon sequestration (CS) that are science based and economically and socially viable. The project consists of three components: (i) remote sensing and carbon modeling, (ii) forest and soil assessment, and (iii) integrated assessment of the socio-economic implications of CS via forest management. Articles included in this special issue are highlights of the results of each of these components.

Identification of Avai polymorphisms in the third intron of GH gene and their associations with abdominal fat in chickens

Growth hormone (GH) plays a diverse role in animals together with other hormones of somatotropic axis. In the current research, chicken GH (cGH) as a candidate gene affecting carcass traits was investigated in the chickens from 2 local chicken breeds [Mountainous Black-Bone (Wugu) and Caoke chicken] in the Sichuan province, 1 pure line of a quality chicken (Sanhuang chicken) from the Guangdong province, and commercial crossbreds. The RFLP method was used to identify polymorphisms of the cGH gene. Three restriction enzyme polymorphic sites were detected in the cGH gene. Sequence alignment from GenBank revealed 2 mutations in the third intron of the cGH gene, which were identified by the AvaI enzyme. Two novel AvaI polymorphic sites were genotyped in 240 chickens from the above-mentioned chicken populations. One EcoRV polymorphic site, the previously reported polymorphism, was also detected in these populations. Significant differences in allelic and genotypic frequencies among all the chicken populations were observed. In AvaI polymorphic sites, allele A2 and B1 had higher frequencies than allele A1 and B2, respectively. In EcoRV polymorphic sites, the frequency of allele N2 was higher than that of allele N1. Associations of polymorphisms of the cGH gene with carcass traits were analyzed by using a GLM procedure. Significant associations were found between AvaI genotypes or combined genotypes and abdominal fat weight and abdominal fat percentage (P<or=0.05). The allele A2 and B1 had a beneficial effect on increasing the live BW, breast muscle weight, and breast muscle percentage while decreasing the abdominal fat weight, abdominal fat percentage, and s.c. fat thickness. No significant associations were observed between EcoRV genotypes and carcass traits. In conclusion, the cGH gene may be a potential marker affecting the abdominal fat trait of chickens.

Transition from two-dimensional to three-dimensional quantum confinement in semiconductor quantum wires/quantum dots

We report the photoluminescence (PL) and polarization-resolved PL characteristics of a novel GaAs/AlGaAs quantum wire/dot semiconductor system, realized by metalorganic vapor-phase epitaxy of site-controlled, self-assembled nanostructures in inverted tetrahedral pyramids. By systematically changing the length of the quantum wires, we implement a continuous transition between the regimes of two-dimensional and three-dimensional quantum confinement. The two main evidences for this transition are observed experimentally and confirmed theoretically: (i) strongly blue-shifted ground-state emission, accompanied by increase separation of ground and excited transition energies; and (ii) change in the orientation of the main axis of linear polarization of the photoluminescence, from parallel to perpendicular with respect to the wire axis. This latter effect, whose origin is shown to be purely due to quantum confinement and valence band mixing, sets in at wire lengths of only approximately 30 nm.

Macrophage biospecific extraction and high performance liquid chromatography for hypothesis of immunological active components in Cordyceps sinensis

A method, namely macrophage biospecific extraction and high performance liquid chromatography for screening potential immunological active components in Cordyceps sinensis, a well-known traditional Chinese medicine, was developed. Two components, which could interact with macrophage, in aqueous extract of C. sinensis (WECS) were found by comparing the HPLC chromatograms of WECS before and after interacted with macrophage. The two compounds were identified as guanosine and adenosine. Their effects on mice macrophage were also investigated in vitro. The results showed that adenosine and guanosine could attenuate NO (p<0.01) but augment interleukin-lbeta (IL-1beta) (p<0.05) release of macrophage during the tested concentrations. In addition, guanosine (0.10 micromol/ml) also increased alpha-tumor necrosis factor (TNF-alpha) release of macrophage. The data suggest that macrophage biospecific extraction and HPLC is a useful method to screen immunological active components from Chinese medicines.

3D-CFD analysis of diffusion and emission of VOCs in a FLEC cavity

This study is performed as a part of research that examines the emission and diffusion characteristics of volatile organic compounds (VOCs) from indoor building materials. In this paper, the flow field and the emission field of VOCs from the surface of building materials in a Field and Laboratory Emission Cell (FLEC) cavity are examined by 3D Computational Fluid Dynamics (CFD) analysis. The flow field within the FLEC cavity is laminar. With a total flow of 250 ml/min, the air velocity near the test material surface ranges from 0.1 to 4.5 cm/s. Three types of emission from building materials are studied here: (i) emission phenomena controlled by internal diffusion, (ii) emission phenomena controlled by external diffusion, and (iii) emission phenomena controlled by mixed diffusion (internal + external diffusion). In the case of internal diffusion material, with respect to the concentration distribution in the cavity, the local VOC emission rate becomes uniform and the FLEC works well. However, in the case of evaporation type (external diffusion) material, or mixed type materials (internal + external diffusion) when the resistance to transporting VOCs in the material is small, the FLEC is not suitable for emission testing because of the thin FLEC cavity. In this case, the mean emission rate is restricted to a small value, since the VOC concentration in the cavity rises to the same value as the surface concentration through molecular diffusion within the thin cavity, and the concentration gradient normal to the surface becomes small. The diffusion field and emission rate depend on the cavity concentration and on the Loading Factor. That is, when the testing material surface in the cavity is partially sealed to decrease the Loading Factor, the emission rate become higher with the decrease in the exposed area of the testing material.

PRACTICAL IMPLICATIONS

The flow field and diffusion field within the FLEC cavity are investigated by CFD method. After presenting a summary of the velocity distributed over the surface of test material and the emission properties of different type materials in FLEC, the paper pointed out that there is a bias in the airflow inside the FLEC cavity but do not influence the result of test emission rate, and the FLEC method is unsuitable for evaporation type materials in which the mass transfer of the surface controls the emission rate.

Mechanisms of quantum dot energy engineering by metalorganic vapor phase epitaxy on patterned nonplanar substrates

A novel technique for tuning the strength of quantum confinement in site-controlled semiconductor quantum dots (QDs) is introduced and investigated theoretically and experimentally. The method makes use of controlled local growth rates during metalorganic vapor phase epitaxy on patterned arrays of inverted pyramids. A model accounting for precursor migration and adatom incorporation predicts the tuning in QD thickness as a function of the pattern parameters. The results are in good agreement with experimental findings. This technique offers means for designing QD photonic structures with potential applications in QD-based cavity quantum electrodynamics and quantum information processing.

The ubiquitin–proteasome system regulates p53-mediated transcription at p21waf1 promoter

The ubiquitin (Ub)-proteasome system (UPS) promotes the proteasomal degradation of target proteins by decorating them with Ub labels. Emerging evidence indicates a role of UPS in regulating gene transcription. In this study, we provided evidence for the involvement of UPS in the transcriptional activation function of tumor suppressor p53. We showed that both ubiquitylation and proteasomal functions are required for efficient transcription mediated by p53. Disruption of transcription by actinomycin D, 5,6-dichloro-1-beta-D-ribofuranosyl-benzimadazole or alpha-amanitin leads to accumulation of cellular p53 protein. Proteasome inhibition by MG132 increases the occupancy of p53 protein at p53-responsive p21(waf1) promoter. In addition, the Sug-1 component of 19S proteasome physically interacts with p53 in vitro and in vivo. Moreover, in response to ultraviolet-induced DNA damage, both the 19S proteasomal components, Sug1 and S1, are recruited to p21(waf1) promoter region in a kinetic pattern similar to that of p53. These results suggested that UPS positively regulates p53-mediated transcription at p21(waf1) promoter.

Assessment of the relative skin sensitization potency of siloranes and bis-GMA using the local lymph node assay and QSAR predicted potency

Siloranes are silicon and oxirane (epoxy) containing monomers used for new dental composite development. The siloranes 3,4-epoxycyclohexylethyl-cyclopolymethylsiloxane (Tet-Sil) and bis-3,4-epoxycyclohexylethyl-phenyl-methylsilane (Ph-Sil) have in common cycloaliphatic epoxy moieties. The epoxy group is of concern in their biocompatibility since most epoxy compounds are known skin sensitizers. The objective of this study was to determine the in vivo skin sensitization potency of the siloranes in the local lymph node assay. A comparison was made with well-known chemical allergens, bis-GMA and DNCB. Female mice (CBA/CaJ) were exposed topically (dorsum of both ears) to several doses of acetone:olive oil in the ratio of 4:1 v/v. Doses were defined by a predictive structure-activity model (QSAR) for contact sensitization. Lymph node cell (LNC) proliferation was measured on the sixth day by incorporation of radioactive thymidine into DNA of lymph node cells. The effective concentration (EC3) that produced a 3-fold stimulation in LNC proliferation relative to controls was extrapolated from dose-response curves. DNCB was a strong sensitizer (EC3 = 0.06%). The EC3 values of Ph-Sil and bis-GMA were 19% and 45%, respectively, making these weak contact sensitizers. Tet-Sil did not increase lymph node proliferation when compared with controls. In contrast to Tet-Sil, the unpolymerized monomers Ph-Sil and bis-GMA have the capacity to induce LNC proliferation, characteristic of a T-cell mediated skin contact sensitization.

Studies of collisional selection rules in thioformaldehyde (H2CS) by microwave-optical double resonance

Individual rotational levels in the A 1A2,v4=1 state of thioformaldehyde (H2CS) are excited by a cw laser and microwave transitions in the region of 8-12 GHz are measured. Some of the microwave frequencies are found to be characteristic of rotational levels other than the level being pumped. Since the microwave frequencies are characteristic of individual rotational levels in the excited state and the excited-state lifetime is approximately 170 micros, information is obtained concerning rotational selection rules during collisions. It is found that J can change by several units and Ka by 0, +/-2, +/-4, and +/-6. The latter result confirms that o-H2CS is not converted to p-H2CS by collisions. Observation of Ka doublets indicates that there are no appreciable differences between the two components.

Highly pathogenic H5N1 influenza virus infection in migratory birds

H5N1 avian influenza virus (AIV) has emerged as a pathogenic entity for a variety of species, including humans, in recent years. Here we report an outbreak among migratory birds on Lake Qinghaihu, China, in May and June 2005, in which more than a thousand birds were affected. Pancreatic necrosis and abnormal neurological symptoms were the major clinical features. Sequencing of the complete genomes of four H5N1 AIV strains revealed them to be reassortants related to a peregrine falcon isolate from Hong Kong and to have known highly pathogenic characteristics. Experimental animal infections reproduced typical highly pathogenic AIV infection symptoms and pathology.

Hypothesis of potential active components in Angelica sinensis by using biomembrane extraction and high performance liquid chromatography

The screening and analysis of bioactive components in traditional Chinese medicines (TCMs) is very important not only for the quality control of crude drugs but also for elucidating the therapeutic principle. In this study, a method for screening potential active components from TCMs was developed by using biomembrane extraction and high performance liquid chromatography. Based on the methodology, aqueous extract of Angelica sinensis (WEAS) was used, and four compounds were detected by HPLC in the desorption eluate of red cell membrane extraction for WEAS. The compounds were identified as ferulic acid, ligustilide, senkyunolide H and senkyunolide I based on their UV, MS and NMR spectra. Actually, ferulic acid and ligustilide are considered as major active components in Angelica sinensis. Therefore, this method may be applied to predict the potential bioactivities of multiple compounds in TCMs simultaneously.

Fludarabine in comparison to alkylator-based regimen as induction therapy for chronic lymphocytic leukemia: a systematic review and meta-analysis

The superiority of Fludarabine over conventional therapy as primary induction therapy for patients with chronic lymphocytic leukemia (CLL) has been shown in several studies but no studies have yet reported a pooled estimate of the treatment effect. We performed a systematic review of evidence from 5 randomized controlled trials involving approximately 1300 patients with CLL, comparing Fludarabine with several alkylator-based combination regimens in the primary treatment of CLL. Complete response rate was significantly higher for Fludarabine compared to alkylator-based chemotherapy (RR 1.87, 95% CI 1.10-3.19, P=0.02), while overall response, though superior, did not reach statistical significance (RR 1.22, 95% CI=0.88-1.69, P=0.24). Overall survival was similar for Fludarabine and alkylator-based therapy (the pooled log hazard ratio of death, HR=-0.05, 95% CI=-0.36-0.26, P=0.75). Infection rate was significantly higher (RR 1.58, 95% CI=1.10-2.27, P=0.01), but there was no significant difference in the incidence of thrombocytopenia, neutropenia and anemia. Therefore, this meta-analysis supports the findings that Fludarabine as an induction agent for patients with CLL yields a better clinical response with acceptable toxicity when compared with alkylator-based combination therapy, but without a survival benefit by 5-6 years of follow up.

Agrin becomes concentrated at neuroeffector junctions in developing rodent urinary bladder

The formation of somatic neuromuscular junctions in skeletal muscle is regulated by an extracellular matrix protein called agrin. Here, we have examined the expression and localization of agrin during development of the rodent urinary bladder, as a first step to examining its possible role at autonomic neuroeffector junctions in smooth muscle. We have found that agrin is expressed on the surface of developing smooth muscle cells and in the basement membrane underlying the urothelium. More importantly, agrin is progressively concentrated at parasympathetic varicosities during postnatal development and is present at virtually all junctions in mature muscle. Reverse transcription/polymerase chain reaction analysis has shown that pelvic ganglion neurons that innervate the bladder express LN/z8 agrin, whereas bladder smooth muscle expresses LN/z- agrin. Together, these results demonstrate that nerve and/or muscle agrin becomes localized at cholinergic parasympathetic varicosities in smooth muscle, where it could play a role in the maturation of the neuroeffector junction.

Estrogen replacement raises rat CRP without evidence of complement activation

Given current controversies regarding anti- and pro-inflammatory effects of estrogen, there is a need to explore relationships between gonadal hormones and inflammation using appropriate animal models. It has been proposed that rats are not appropriate for such research since, contrary to the effect of estrogen in humans, earlier animal studies had reported that estrogen downregulates serum C-reactive protein (rCRP) levels in the rat. With these considerations in mind, we re-examined the effects of estrogen withdrawal and replacement on CRP expression and complement activation in the rat. F-344 rats underwent bilateral ovariectomy or sham surgery at 9-10 months of age. Four months later, ovariectomized rats were treated with traditional high-dose 17beta-estradiol (Hi-E2) capsules, lower-dose (Lo-E2) 17beta-estradiol capsules, or placebo capsules for 7 days prior to sacrifice. Levels of plasma rat C-reactive protein (rCRP) were significantly lower in ovariectomized vs. sham-operated animals (415.5 +/- 10.6 vs. 626.6 +/- 23.0 mg/L, p < 0.001). Estrogen replacement significantly raised rCRP levels in ovariectomized animals (690.0 +/- 28.0 mg/L in Lo-E2 and 735.5 +/- 35.8 mg/L in Hi-E2, respectively, p < 0.001). Plasma rCRP levels correlated significantly with both hepatic rCRP (r = 0.79, p < 0.001) and serum estradiol (r = 0.70, p < 0.001) levels. However, no significant differences were observed in indices of complement activation (C4b/c) or CRP-complement complex generation (rCRP-C3 complex). In the mature female rat, ovariectomy reduces and estrogen replacement raises rCRP. Effects of estrogen on plasma rCRP induction are mediated, at least in part, through hepatic mechanisms and do not appear to require or be associated with complement activation.

Inhaled IFN-gamma for persistent nontuberculous mycobacterial pulmonary disease due to functional IFN-gamma deficiency

Pulmonary infection with nontuberculous mycobacteria (NTM) in previously healthy human immunodeficiency virus-seronegative individuals is difficult to treat. Recently, functional interferon (IFN)-gamma deficiency has been identified in individuals susceptible to this disease. Treatment with inhaled IFN-gamma for NTM pulmonary disease associated with functional IFN-gamma deficiency has not been previously described. In this study, the IFN-gamma pathway was characterised in an individual who had progressive NTM pulmonary infection, despite appropriate multidrug antibiotic therapy, and 10 healthy controls. Levels of IFN-gamma and tumour necrosis factor-alpha in whole blood were assessed before and after incubation with lipopolysaccharide, heat-killed Escherichia coli, heat-killed Staphylococcus aureus and phorbol myristate acetate/ionomycin. The coding regions of interleukin (IL)-12, IL-18 and the IL-12 receptor were sequenced using nested primers. IFN-gamma1b (100 microg.dose(-1)) was administered to the affected individual by ultrasonic nebuliser 3 days.week(-1) for 3 months. In vitro whole blood production of IFN-gamma with and without physiological stimuli was consistent with functional IFN-gamma deficiency in the affected individual. There was no evidence of mutation in the coding regions of IL-12p35, IL-12p40, IL-12Rbeta1 and IL-18 in the affected individual. Treatment with inhaled IFN-gamma resulted in rapid and sustained clearance of the organism from the airways and stabilisation of lung function. In conclusion, inhaled interferon-gamma can be effective for the treatment of nontuberculous mycobacteria pulmonary disease associated with functional interferon-gamma deficiency.