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Energy generation and consumption have always been an important component of social development. Interests in this field are beginning to shift to indoor photovoltaics (IPV) which can serve as power sources under low light conditions to meet the energy needs of rapidly growing fields, such as intelligence gathering and information processing which usually operate via the Internet‐of‐things (IoT). Since the power requirements for this purpose continue to decrease, IPV systems under low light may facilitate the realization of self‐powered high‐tech electronic devices connected through the IoT. This review discusses and compares the characteristics of different types of IPV devices such as those based on silicon, dye, III‐V semiconductors, organic compounds, and halide perovskites. Among them, specific attention is paid to perovskite photovoltaics which may potentially become a high performing IPV system due to the fascinating photophysics of the halide perovskite active layer. The limitations of such indoor application as they relate to the toxicity, stability, and electronic structure of halide perovskites are also discussed. Finally, strategies which could produce highly functional, nontoxic, and stable perovskite photovoltaics devices for indoor applications are proposed. 相似文献
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Objective
To investigate the effect of surgical decompression on painful diabetic peripheral neuropathy (DPN) patients and discuss the role which pain distribution and characterization play in the management of painful DPN as well as the underlying mechanism involved.Methods
A total of 306 patients with painful diabetic lower-extremity neuropathy were treated with Dellon surgical nerve decompression in our department. Clinical evaluation including Visual analogue scale (VAS), Brief Pain Inventory Short Form for diabetic peripheral neuropathy (BPI-DPN) questionnaire, two-point discrimination (2-PD), nerve conduction velocity (NCV) and high-resolution ultrasonography (cross-sectional area, CSA) were performed in all cases preoperatively, and at 6 month intervals for 2 years post-decompression. The patients who underwent surgery were retrospectively assigned into two subgroups (focal and diffuse pain) according to the distribution of the diabetic neuropathic pain. The control group included 92 painful DPN patients without surgery.Results
The levels of VAS, scores in BPI-DPN, 2-PD, NCV results and CSA were all improved in surgical group when compared to the control group (P<0.05). More improvement of VAS, scores in BPI-DPN and CSA was observed in focal pain group than that in diffuse group (P<0.05).Conclusions
Efficacy of decompression of multiple lower-extremity peripheral nerves in patients with painful diabetic neuropathy was confirmed in this study. While both focal and diffuse group could benefit from surgical decompression, pain relief and morphological restoration could be better achieved in focal group. 相似文献27.
Cobalt-rich crusts are important metallic mineral resources with great economic potential, usually distributed on seamounts located in the Pacific Ocean. Microorganisms are believed to play a role in the formation of crusts as well as in metal cycling. To explore the microbial diversity related to cobalt-rich crusts, 16S ribosomal RNA gene clone libraries were constructed from three consecutive sediment layers. In total, 417 bacterial clones were obtained from three bacterial clone libraries, representing 17 distinct phylogenetic groups. Proteobacteria dominated in the bacterial communities, followed by Acidobacteria and Planctomycetes. Compared with high bacterial diversity, archaea showed a remarkably low diversity, with all 137 clones belonging to marine archaeal group I except one novel euryarchaeotal clone. The microbial communities were potentially involved in sulfur, nitrogen and metal cycling in the area of cobalt-rich crusts. Sulfur oxidation and metal oxidation were potentially major sources of energy for this ecosystem. This is the first reported investigation of microbial diversity in sediments associated with cobalt-rich crusts, and it casts fresh light on the microbial ecology of these important ecosystems. 相似文献
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Multiple evidence shows that metformin serves as a potential agent for Colorectal Cancer (CRC) treatment, while its molecular mechanisms still require detailed investigation. Here, we revealed that metformin specifically suppressed the proliferation of CRC cells by causing G1/S arrest, and INHBA is a potential target for metformin to play an anti-proliferation effect in CRC. We verified the oncogene role of INHBA by knocking down and overexpressing INHBA in CRC cells. Silencing INHBA abrogated the cell growth, while overexpression INHBA promotes the proliferation of CRC cells. As an oncogene, INHBA was aberrant overexpression in CRC tissues and closely related to the poor prognosis of CRC patients. In mechanism, INHBA is an important ligand of TGF-β signaling and metformin blocked the activation of TGF-β signaling by targeting INHBA, and then down-regulated the activity of PI3K/Akt pathway, leading to the reduction of cyclinD1 and cell cycle arrest. Together, these findings indicate that metformin down-regulates the expression of INHBA, then attenuating TGF-β/PI3K/Akt signaling transduction, thus inhibiting the proliferation of CRC. Our study elucidated a novel molecular mechanism for the anti-proliferation effect of metformin, providing a theoretical basis for the application of metformin in CRC therapy.Subject terms: Colorectal cancer, Cell growth, Target identification 相似文献
29.
The present paper reports the chromosome numbers and karyotypes of 5 species
in Ranunculus from Jiangxi. The result is shown in Table 1-2. The chromosome numbers of
R. ternatus Thunb. (2n=4x=32; 2n=2x=16=8m+2sm+6st) , R. polii Franch.
(2n = 2x = 16 = 8m+2sm+6st) and R. sieboldii Miq. (2n = 8x-1 = 63 = 15m+18sm+22st+8t) are
first reported. The essential points are as follows:
(1) The karyotypes of R. ternatus Thunb. and R. polii Franch. are rather similar, which
shows a close relationship between the two species.
(2) Polyploid complexes are common in Ranunculus.
(3) According to the taxonomical system of Wang Wen-cai, the karyotypes of the two
species investigated in Sect. Auricomus belong to “2A” of Stebbins; that of the only species in
Sect. Hecatonia belong to “2B'; the karyotypes of the two species investigated in Sect.
Ranunculus belong to “3A” or “3B”. The relationships among the three sections from thekaryotype are basically consistent with those based on morphology. 相似文献
30.
The technical feasibility of adopting the fixed-film reactor concept for biogas production from screened dairy manure was investigated. The methane production capability of laboratory-scale 4-L anaerobic reactors (conventional and fixed-film) receiving screened dairy manure and operated at 35 degrees C was compared. Dairy manure filtrate with 4.4% total solids (TS) and 3.4% volatile solids (VS) (average value) was prepared from 1:1 manure-water slurry. The feed material was added intermittently at loading rates ranging from 2.34 to 25 and 2.25 to 785 g VS/L d, respectively, for the conventional and fixed-film reactors. Maximum methane production rate (L CH(4)/L d) for the conventional reactor was 0.63 L CH(4)/L d achieved at a 6-day hydraulic retention time (HRT). For the fixed-film reactor the maximum production rate was 3.53 L CH(4)/L d when operated at a loading rate of 262 g VS/L d (3 h HRT). The fixed-film reactor was capable of sustaining a loading of 785 g VS/L d (1 h HRT). The fixed-film reactor performed much better than the conventional reactors. These results indicate that a large reduction of required reactor volume is possible through application of a fixed-film concept combined with a liquid-solid separation pretreatment of dairy manure. 相似文献