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We have demonstrated that the edge recombination effect exists in full area industrial silicon heterojunction (SHJ) solar cells, which can cause significant short-circuit current density (JSC) loss. The mechanism behind this observation was studied using different SHJ cell structures. We demonstrated further that this JSC loss effect can be suppressed effectively by simply controlling the gap between the edge of the transparent conductive oxide layer and that of the cell. Using this strategy, the average JSC of our state-of-art SHJ solar cells was enhanced by 0.36 mA/cm2, resulting in an average efficiency gain of 0.28% absolute.

Forest landowner cooperatives have emerged as a formal institution capable of fostering professional forest management. There are many reasons to motivate participation in forest cooperatives. For instance, cooperatives could ease nonindustrial family forest landowners (NIFFLs) access to financial assistance and enhance market entrance opportunities. In China, various forms of forest cooperatives supported by government agencies are developing rapidly in an effort to facilitate forest management at a large scale. However, the development of forest cooperatives is still in its early stages. An understanding of NIFFLs' attitudes towards the development of cooperatives is instrumental for crafting policies and organizational structures that motivate landowners' participation. Three hundred and ten NIFFLs from Fujian and Jiangxi provinces in Southern China were interviewed to elicit their attitudes and willingness-to-participate in forest cooperatives. Logistic regression was used to evaluate landowner, household, forest resource, and institutional factors associated with NIFFLs' stated decision to participate in a forest cooperative. Results show that NIFFLs' stated willingness-to-participate in forest cooperatives was associated with demographic characteristics like education, forest-related income, size of forestland, and attitudes toward land tenure reform and cooperatives. This paper outlines suggestions on how to further develop forest cooperatives in Southern China.

Although in vivo electroporation (EP) has been utilized to improve immunogenicity in DNA vaccines alone or in prime-boost regimens with both proteins and viral-vectors, no studies on in vivo EP in DNA-VLP prime-boost regimens against HIV-1 have been reported. Previously we developed stably transfected Drosophila S2 clones to produce HIV-1 virus-like particles (VLP) and demonstrated that priming mice twice with DNA plasmids encoding HIV-1 gp120 and gag and boosting twice with HIV-1 VLP (i.e. DDVV immunization) elicited both envelope-specific antibody and envelope and gag-specific CD8 T cell responses. However, the potency and the breadth of immunogenicity still need to be improved. In this study we tested the effect of in vivo EP during DNA priming on immunogenicity of this DNA-VLP prime-boost regimen. Here we report that although both DDVV and DDVV+EP elicited gp120-specific ELISA-binding antibody responses, average EC50 values of gp120-specific ELISA-binding total IgG, IgG2a, but not IgG1, antibody responses were significantly higher in DDVV+EP than in DDVV. Moreover, while DDVV elicited neutralizing antibody responses against autologous, but not other five, strains tested, DDVV+EP not only elicited significantly higher anti-autologous neutralizing antibody responses, but also cross-neutralizes four of five other HIV-1 strains tested, including two tier 2 strains. Finally, although CD4 and CD8 T cells from both DDVV and DDVV+EP immunizations secreted IFN-γ, IL-2, TNF-α upon HIV-1 envelope peptide stimulation, average HIV-1 envelope-specific CD8 T cells that secreted IFN-γ, IL-2 and/or TNF-α were significantly higher in DDVV+EP than in DDVV. Thus we conclude that DDVV+EP immunization preferentially increases HIV-1 envelope-specific TH1 cytokine-mediated IgG2a responses and significantly enhances the potency and the breadth of neutralizing antibody responses including tier 2 viruses. Further study on this heterologous regimen in large animals is warranted.

Decellularized liver matrix (DLM) hold great potential for reconstructing functional hepatic-like tissue (HLT) based on reseeding of hepatocytes or stem cells, but the shortage of liver donors is still an obstacle for potential application. Therefore, an appropriate alternative scaffold is needed to expand the donor pool. In this study, we explored the effectiveness of decellularized spleen matrix (DSM) for culturing of bone marrow mesenchymal stem cells (BMSCs), and promoting differentiation into hepatic-like cells.Rats' spleen were harvested for DSM preparation by freezing/thawing and perfusion procedure. Then the mesenchymal stem cells derived from rat bone marrow were reseeded into DSM for dynamic culture and hepatic differentiation by a defined induction protocol.The research found that DSM preserved a 3-dimensional porous architecture, with native extracellular matrix and vascular network which was similar to DLM. The reseeded BMSCs in DSM differentiated into functional hepatocyte-like cells, evidenced by cytomorphology change, expression of hepatic-associated genes and protein markers, glycogen storage, and indocyanine green uptake. The albumin production (2.74±0.42 vs. 2.07±0.28 pg/cell/day) and urea concentration (75.92±15.64 vs. 52.07±11.46 pg/cell/day) in DSM group were remarkably higher than tissue culture flasks (TCF) group over the same differentiation period, P0.05.This present study demonstrated that DSM might have considerable potential in fabricating hepatic-like tissue, particularly because it can facilitate hepatic differentiation of BMSCs which exhibited higher level and more stable functions.

The energy band diagram of the HIT solar cell obtained using AFORS-HET simulations reveals that a p-type inversion layer is induced in the n-type c-Si near the front hetero-interface. The HIT solar cell actually behaves like a "pseudo" p-n homojunction solar cell, in which the p-type inversion layer acts as the cell emitter and controls the performance of the solar cell. The formation of the inversion layer is controlled by the Fermi level of the p-Si:H layer, which is adjustable by varying its doping level. The study also suggests that the work function of the front TCO layer should be keep as high as possible for achieving high conversion efficiency.

A pot culture experiment of nitrogen forms [nitrate (NO− 3 ): ammonium (NH + 4 )] with four ratios (100:0, 75:25, 50:50, and 25:75) in nutrient solutions was conducted to examine the effect of nitrogen forms on the growth and polyamine contents of developing seeds of vegetable soybean [Glycine max (L.) Merr. cv. ‘Li-xiang 95-1′]. Results showed that the best plant growth vigor was observed in (75%), and then in (50%). However, the fresh and dry weight of biomass decreased when a high concentration of either (100%) or (75%) was the primary nitrogen source in the nutrient solution. The numbers of flowers and pods in (75%) were significantly decreased compared with other ammonium-nitrate ratios in which the numbers of flowers and pods were not influenced by nitrogen forms. During the development of seeds, levels of free Put and Spd decreased, and the decrease extents were more marked in 100:0 and 25:75 (:), but the change of free Spm was opposite. Levels of conjugated and bound polyamines in all nitrogen for...

We present industrialized bifacial solar cells on large area (149 cm2) 2 cm CZ monocrystalline silicon wafers processed with industrially relevant techniques such as liquid source BBr3 and POCl3 open-tube furnace diffusions, plasma enhanced chemical vapor deposition (PECVD) SiNx deposition, and screen printed contacts. The fundamental analysis of the paste using at boron-diffused surface and the bifacial solar cell firing cycle has been investigated. The resulting solar cells have front and rear efficiencies of 16.6 and 12.8%, respectively. The ratio of the rear JSC to front JSC is 76.8%. It increases the bifacial power by 15.4% over a conventional solar cell at 20% of 1-sun rear illumination, which equals to the power of a conventional solar cell with 19.2% efficiency. We also present a bifacial glass–glass photovoltaic (PV) module with 30 bifacial cells with the electrical characteristics. Copyright © 2010 John Wiley & Sons, Ltd.

The purpose of this work is to improve the precision of the elemental analysis of coal using laser-induced breakdown spectroscopy (LIBS). The LIBS technique has the ability to allow simultaneous elemental analysis and on-line determination, so it could be used in the elemental analysis of coal. Organic components such as C, H, O, N and inorganic components such as Ca, Mg, Fe, Al, Si, Ti, Na, and K of coal have been identified. The precision of the LIBS technique depends strongly on the experimental conditions, and the choice of experimental parameters should be aimed at optimizing the repeatability of the measurements. The dependences of the relative standard deviation (RSD) of the LIBS measurements on the experimental parameters including the sample preparation parameters, lens-to-sample distance, sample operation mode, and ambient gas have been investigated. The results indicate that the precision of LIBS measurements for the coal sample can be improved by using the optimum experimental parameters.

The Na-doped p-type ZnO thin films were prepared by DC reactive magnetron sputtering. Two types of substrates were used for separate testing purposes: silicon wafers for crystallinity measurements and glass slides for electrical and optical transmittance measurements. The lowest room-temperature resistivity under the optimal condition was 59.9 Ω cm, with a Hall mobility of 0.406 cm2 V−1s−1 and a carrier concentration of 2.57 × 1017 cm−3. The Na-doped ZnO thin films possessed a good crystallinity with c-axis orientation and a high transmittance (∼85%) in the visible region. The effects of the substrate temperature on the crystallinity and the electrical properties were discussed.

We report measurements of the physical properties and electronic structure of the hexagonal compounds Yb2Ni12Pn7 (Pn = P, As) by measuring the electrical resistivity, magnetization, specific heat and partial fluorescence yield x-ray absorption spectroscopy (PFY-XAS). These demonstrate a crossover upon reducing the unit cell volume, from an intermediate valence state in Yb2Ni12As7 to a heavy-fermion paramagnetic state in Yb2Ni12P7, where the Yb is nearly trivalent. Application of pressure to Yb2Ni12P7 suppresses T_FL, the temperature below which Fermi liquid behavior is recovered, suggesting the presence of a quantum critical point (QCP) under pressure. However, while there is little change in the Yb valence of Yb2Ni12P7 up to 30 GPa, there is a strong increase for Yb2Ni12As7 under pressure, before a near constant value is reached. These results indicate that any magnetic QCP in this system is well separated from strong valence fluctuations. The pressure dependence of the valence and lattice parameters of Yb2Ni12As7 are compared and at 1 GPa, there is an anomaly in the unit cell volume as well as a change in the slope of the Yb valence, indicating a correlation between structural and electronic changes., Comment: 11 pages, 9 figures

Organic/silicon nanowires (SiNWs) hybrid solar cells have recently been recognized as one of potentially low-cost candidates for photovoltaic application. Here, we have controllably prepared a series of uniform silicon nanowires (SiNWs) with various diameters on silicon substrate by metal-assisted chemical etching followed by thermal oxidization and then fabricated the organic/SiNWs hybrid solar cells with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS). It is found that the reflective index of SiNWs layer for sunlight depends on the filling ratio of SiNWs. Compared to the SiNWs with the lowest reflectivity (LR-SiNWs), the solar cell based on the SiNWs with low filling ratio (LF-SiNWs) has a higher open-circuit voltage and fill factor. The capacitance-voltage measurements have clarified that the built-in potential barrier at the LF-SiNWs/PEDOT:PSS interface is much larger than that at the LR-SiNWs/PEDOT one, which yields a strong inversion layer generating near the silicon surface. The formation of inversion layer can effectively suppress the carrier recombination, reducing the leakage current of solar cell and meanwhile transfer the LF-SiNWs/PEDOT:PSS device into a p-n junction. As a result, a highest efficiency of 13.11% is achieved for the LF-SiNWs/PEDOT:PSS solar cell. These results pave a way to the fabrication of high efficiency organic/SiNWs hybrid solar cells.

To optimize the protocols for isolation, in vitro culture, identification and induction of hepatic differentiation of rat bone marrow mesenchymal stem cells (BMSCs).Rat BMSCs were separated and purified by differential adherent culture for 1.5 h with the first medium change at 12 h. The surface markers of BMSCs were detected by flow cytometry. The cells were induced to differentiate into adipogenic, osteogenic, and chondrogenesis lineages. A 3-step protocol including sequential addition of growth factors, cytokines and hormones was used to induce the BMSCs to differentiate into hepatocyte-like cells.The cells isolated using this protocol were positive for CD29, CD44, and CD90 and negative for CD29 and CD45. The adipogenic, osteogenic, and chondrogenic differentiation of the BMSCs were verified by Oil red, Alizarin red, and toluidine blue staining. The BMSCs induced with the 3-step protocol differentiated into hepatic-like cells that expressed hepatocyte-specific proteins (ALB and AFP) and genes.The optimized protocol allows simple and efficient isolation of highly purified populations of BMSCs, which can be induced into hepatic lineages in specific microenvironment.

Graphene-silicon (Gr-Si) heterojunction solar cells have been recognized as one of the most low-cost candidates in photovoltaics due to its simple fabrication process. However, the high sheet resistance of chemical vapor deposited (CVD) Gr films is still the most important limiting factor for the improvement of the power conversion efficiency of Gr-Si solar cells, especially in the case of large device-active area. In this work, we have fabricated a novel transparent conductive film by hybriding a monolayer Gr film with silver nanowires (AgNWs) network soldered by the graphene oxide (GO) flakes. This Gr-AgNWs hybrid film exhibits low sheet resistance and larger direct-current to optical conductivity ratio, quite suitable for solar cell fabrication. An efficiency of 8.68% has been achieved for the Gr-AgNWs-Si solar cell, in which the AgNWs network acts as buried contacts. Meanwhile, the Gr-AgNWs-Si solar cells have much better stability than the chemically doped Gr-Si solar cells. These results show a new route for the fabrication of high efficient and stable Gr-Si solar cells.

Graphene-silicon (Gr-Si) Schottky solar cell has attracted much attention recently as promising candidate for low-cost photovoltaic application. For the fabrication of Gr-Si solar cell, the Gr film is usually transferred onto the Si substrate by wet transfer process. However, the impurities induced by this process at the graphene/silicon (Gr/Si) interface, such as H2O and O2, degrade the photovoltaic performance of the Gr-Si solar cell. We found that the thermal annealing process can effectively improve the photovoltaic performance of the Gr-Si solar cell by removing these impurities at the Gr/Si interface. More interestingly, the photovoltaic performance of the Gr-Si solar cell can be improved, furthermore, when exposed to air environment after the thermal annealing process. Through investigating the characteristics of the Gr-Si solar cell and the properties of the Gr film (carrier density and sheet resistance), we point out that this phenomenon is caused by the natural doping effect of the Gr film.

We study the superconducting properties of the polycrystalline LaNiC2 by means of measuring the electrical resistivity ρ(T), magnetization M(T) and London penetration depth Δλ(T). The superconducting order parameter is analyzed in terms of the low temperature penetration depth Δλ(T) and the corresponding superfluid density ρs(T), and the results show strong evidence of two-gap Bardeen-Cooper-Schrieffer (BCS) superconductivity for LaNiC2.

PG9 and PG16 are two quaternary-structure-specific broadly neutralizing antibodies with unique HCDR3 subdomains. Previously, we showed that glycosylphosphatidylinositol (GPI)-anchored HCDR3 subdomains (GPI-HCDR3) can be targeted to lipid rafts of the plasma membrane, bind to the epitope recognized by HCDR3 of PG16, and neutralize diverse HIV-1 isolates. In this study, we further developed trimeric GPI-HCDR3s and demonstrated that trimeric GPI-HCDR3 (PG16) dramatically improves anti-HIV-1 neutralization, suggesting that a stoichiometry of recognition of 3 or 2 HCDR3 molecules (PG16) to 1 viral spike is possible.

The development of a successful vaccine against human immunodeficiency virus type 1 (HIV-1) likely requires immunogens that elicit both broadly neutralizing antibodies against envelope spikes and T cell responses that recognize multiple viral proteins. HIV-1 virus-like particles (VLP), because they display authentic envelope spikes on the particle surface, may be developed into such immunogens. However, in one way or the other current systems for HIV-1 VLP production have many limitations. To overcome these, in the present study we developed a novel strategy to produce HIV-1 VLP using stably transfected Drosophila S2 cells. We cotransfected S2 cells with plasmids encoding HIV-1 envelope, Gag, and Rev proteins and a selection marker. After stably transfected S2 clones were established, HIV-1 VLP and their immunogenicity in mice were carefully evaluated. Here, we report that HIV-1 envelope proteins are properly cleaved, glycosylated, and incorporated into VLP with Gag. The amount of VLP released into culture supernatants is comparable to those produced by insect cells infected with recombinant baculoviruses. Moreover, cryo-electron microscopy tomography revealed average 17 spikes per purified VLP, and antigenic epitopes on the spikes were recognized by the broadly neutralizing antibodies 2G12, b12, VRC01, and 4E10 but not by PG16. Finally, mice primed with DNA and boosted with VLP in the presence of CpG exhibited anti-envelope antibody responses, including ELISA-binding, neutralizing, antibody-dependent cell-mediated cytotoxicity and antibody-dependent cell-mediated viral inhibition, as well as envelope and Gag-specific CD8 T cell responses. Thus, we conclude that HIV-1 VLP produced by the S2 expression system has many desirable features to be developed into a vaccine component against HIV-1.

With the development of stage lighting technology, people have increasing demands for the lighting control, such as real-time and portable, However, existing LED dimming control equipments usually have large size and complicated functions, so they are not easy to move and operate. In order to improve these problems, this paper proposes a portable LED stage lighting control system and designed its software and hardware. Its hardware is composed of three parts: stage lighting manipulator, the communication lines based on DMX512 protocol and LED dimming control circuit. ATmega16 is the core of the control system. Data transmission follows the DMX512 protocol. The test results showed this system had stable performance and high reliability, which can completely met the requirement of stage lighting control. Its simple structure and convenient operation made it easy to carry and use. Meanwhile, using LED lamps instead of traditional ones can effectively save energy.

With the rapid development of stage equipment in recent years, the traditional SCR Dimming control technology is difficult to complete the performance requirements of stage lighting. In this paper, we proposed and researched the stage lighting dimming control technology based on sine wave, which used Atmega16 microcontroller, IXDP610 chip and IGBT as the main hardware. We could receive the DMX512 data sent from lighting console, and control IXDP610 chip to generate PWM signal with adjustable duty cycle and dead time by the microcontroller. This PWM signal can control the IGBT through driving circuit to achieve the purpose of dimming. According to the simulation and experimental results, this technology has a good dimming performance and it can effectively avoid the generation of harmonics. The research has theoretical significance and practical value to the development of stage lighting dimming control technology.

PG9 and PG16 are two recently isolated quaternary-specific human monoclonal antibodies that neutralize 70 to 80% of circulating HIV-1 isolates. The crystal structure of PG16 shows that it contains an exceptionally long CDR H3 that forms a unique stable subdomain that towers above the antibody surface to confer fine specificity. To determine whether this unique architecture of CDR H3 itself is sufficient for epitope recognition and neutralization, we cloned CDR H3 subdomains derived from human monoclonal antibodies PG16, PG9, b12, E51, and AVF and genetically linked them to a glycosyl-phosphatidylinositol (GPI) attachment signal. Each fusion gene construct is expressed and targeted to lipid rafts of plasma membranes through a GPI anchor. Moreover, GPI-CDR H3(PG16, PG9, and E51), but not GPI-CDR H3(b12 and AVF), specifically neutralized multiple clades of HIV-1 isolates with a great degree of potency when expressed on the surface of transduced TZM-bl cells. Furthermore, GPI-anchored CDR H3(PG16), but not GPI-anchored CDR H3(AVF), specifically confers resistance to HIV-1 infection when expressed on the surface of transduced human CD4 + T cells. Finally, the CDR H3 mutations (Y100HF, D100IA, and G7) that were previously shown to compromise the neutralization activity of antibody PG16 also abolished the neutralization activity of GPI-CDR H3(PG16). Thus, we conclude that the CDR H3 subdomain of PG16 neutralizes HIV-1 when targeted to the lipid raft of the plasma membrane of HIV-1-susceptible cells and that GPI-CDR H3 can be an alternative approach for determining whether the CDR H3 of certain antibodies alone can exert epitope recognition and neutralization.

It is well-known that RCM is an advanced and effective maintenance strategy in practice. With the development of the automation and mechanization in modern industry, RCM method turns to be complex and consumes more resources in real production. However, the development and application of the Streamline RCM (SRCM) has injected new vitality for the new situation, especially in the nuclear power plants. This paper firstly introduces the background, the characteristics of the SRCM and the differences from RCM, and then shows the process in detail as well as the application status of the SRCM in country and abroad. It is proved that SRCM is a unique available method which saves the time and resource consumed, ensuring the integrity and correctness of the classical RCM. Finally, the weak points and the prospect are reviewed and prospected.Copyright © 2010 by ASME