Influence of Reaction Temperature on Optical Property of Mn-Doped ZnS Nanoparticles

The reaction temperature has essential effect on quality of the product synthesized by hydrothermal method. We report here the variation of the optical characteristics of Mn-doped ZnS nanocrystallites prepared by mean of the stated method from Zn(CH$_{3}$COO)$_{2}$.2H$_{2}$O, Mn(CH$_{3}$COO)$_{2}$.4H$_{2}$O and Na$_{2}$S$_{2}$O$_{3}$.5H$_{2}$O as the precursors. The reaction temperature was set to vary from 120\r{}C to 240\r{}C at a constant reaction time of 15 hours. The XRD patterns showed that, for the reaction temperature range from 120 to 160\r{}C, the obtained products possessed a cubic $T_d^2 - F\overline 4 3m$ and a wurtzite $C_{6v}^4 - P6_3 mc$structure, in which the cubic phase was dominant. At the temperature range from 180 to 240\r{}C, the structures exhibited a cubic phase with the lattice constant increased from 5.41 to 5.43 {\AA}. The photoluminescence spectra showed that with the increase of reaction temperature from 120 to 240\r{}C the intensity of a blue band around 425 - 500 nm (attributed to both Zn, S vacancies) gradually decreased while the intensity of a yellow-orange band at 585 nm (attributed to the $^{4}$T$_{1}(^{4}$G) - $^{6}$A$_{1}(^{6}$S) transition of Mn$^{2 + }$ ions) was enhanced and reached maximum at 220\r{}C. The excitation spectra of the 585 nm band recorded at 160\r{}C showed a band at 335 nm which should be assigned to the near band-edge absorption. With increasing temperature to 200-240\r{}C the new bands appeared at 390, 430, 467, 494 nm. The intensity of these bands increased with temperature and achieved the maxima at 220\r{}C. They should be attributed to the absorption transitions of electrons from ground state $^{6}$A$_{1}(^{6}$S) to excited states$^{ 4}$E($^{4}$D); $^{4}$T$_{2}(^{4}$D); $^{4}$A$_{1}(^{4}$G) - $^{4}$E($^{4}$G); $^{4}$T$_{2}(^{4}$G) of Mn$^{2 + }$(3d$^{5})$ ions, respectively. The bands at 467, 494 nm only exposed clearly in the absorption spectra at 220\r{}C and 240\r{}C

A Comprehensive Lighting Configuration for Efficient Indoor Visible Light Communication Networks

Design of an efficient indoor visible light communication (VLC) system requires careful considerations on both illumination and communication aspects. Besides fundamental factors such as received power and signal-to-noise ratio (SNR) level, studies on mobility scenarios and link switching process must be done in order to achieve good communication link quality in such systems. In this paper, a comprehensive lighting configuration for efficient indoor VLC systems for supporting mobility and link switching with constraint on illumination, received power, and SNR is proposed. Full connectivity in mobility scenarios is required to make the system more practical. However, different from other literatures, our work highlights the significance of recognizing the main influences of field of view angle on the connectivity performance in the practical indoor scenarios. A flexible link switching initiation algorithm based on the consideration of relative received power with adaptive hysteresis margin is demonstrated. In this regard, we investigate the effect of the overlap area between two light sources with respect to the point view of the receiver on the link switching performance. The simulation results show that an indoor VLC system with sufficient illumination level and high communication link quality as well as full mobility and support link switching can be achieved using our approach

Functional Complementation Studies and Analysis of Downstream Regulatory Gene Expression Networks of Trichome Trimeric Complex

In Arabidopsis, previous genetic analysis has revealed that trichome initiation is positively mediated by a trimeric activation complex comprised of an R2R3-MYB protein GLABRA1 (GL1), a basic helix-loop-helix (bHLH) GLABRA3 (GL3) which acts redundantly with its close homolog ENHANCER OF GLABRA3 (EGL3), and a WD40 protein TRANSPARENT TESTA GLABRA1 (TTG1). We studied the functionality of four individual cotton genes MYB2, TTG3, DEL65 and DEL61 from diploid cotton A and D genomes, which show high similarity in sequence with GL1, TTG1, GL3 and EGL3, respectively, in their respective Arabidopsis glabrous mutants. Our complementation assays proved that transgenic lines with MYB2, TTG3 from diploid genomes A and D could rescue the trichomeless phenotype of gl1-1 and ttg1-1, respectively. However, DEL61 from both the species could not rescue this phenotype of gl3-1 egl3-77439 double mutant. Interestingly, the DEL65 from A species rescued gl3-1 egl3-77439 double mutant but not from D diploid species. Comparative quantitative PCR analysis of the downstream regulatory network genes showed a similar pattern for MYB, TTG3 complemented lines from A- and D- diploid species. Comparative analysis of the DEL65 from A- (rescued the trichomeless phenotype) and D- (did not rescued the trichomeless phenotype) showed differential expression of regulatory network genes between these two lines. These results suggested that MYB2, TTG3 and DEL65, when expressed in Arabidopsis, regulated the regulatory network genes during the trichome initiation process

A Large-Scale Study of a Sleep Tracking and Improving Device with Closed-loop and Personalized Real-time Acoustic Stimulation

Various intervention therapies ranging from pharmaceutical to hi-tech tailored solutions have been available to treat difficulty in falling asleep commonly caused by insomnia in modern life. However, current techniques largely remain ill-suited, ineffective, and unreliable due to their lack of precise real-time sleep tracking, in-time feedback on the therapies, an ability to keep people asleep during the night, and a large-scale effectiveness evaluation. Here, we introduce a novel sleep aid system, called Earable, that can continuously sense multiple head-based physiological signals and simultaneously enable closed-loop auditory stimulation to entrain brain activities in time for effective sleep promotion. We develop the system in a lightweight, comfortable, and user-friendly headband with a comprehensive set of algorithms and dedicated own-designed audio stimuli. We conducted multiple protocols from 883 sleep studies on 377 subjects (241 women, 119 men) wearing either a gold-standard device (PSG), Earable, or both concurrently. We demonstrate that our system achieves (1) a strong correlation (0.89 +/- 0.03) between the physiological signals acquired by Earable and those from the gold-standard PSG, (2) an 87.8 +/- 5.3% agreement on sleep scoring using our automatic real-time sleep staging algorithm with the consensus scored by three sleep technicians, and (3) a successful non-pharmacological stimulation alternative to effectively shorten the duration of sleep falling by 24.1 +/- 0.1 minutes. These results show that the efficacy of Earable exceeds existing techniques in intentions to promote fast falling asleep, track sleep state accurately, and achieve high social acceptance for real-time closed-loop personalized neuromodulation-based home sleep care.Comment: 33 pages, 8 figure

Targeting effect of folate on cancer cell through curcumin carrier nano-system

Folate receptor (FR) is well known for its overexpression on surface of various cancer cell lines, which is identical to normal tissue. Folic-based targeting drug delivery systems, therefore, are one of the most effective targeting carriers that effectively bind to FR up-regulated cancer cells. Curcumin was used both for labeling and chemotherapy. The materials were characterized and structurally confirmed by FT-IR spectra, fluorescent images and FE-SEM images. Bioassays were conducted on HeLa and HT29 cancer cell lines after 4 and 12 hours. Results show that folic acid significantly enhanced both targeting efficiency and internalization of curcumin to FR-expressing cancer cells

A comprehensive study on the efficacy of a wearable sleep aid device featuring closed-loop real-time acoustic stimulation

Difficulty falling asleep is one of the typical insomnia symptoms. However, intervention therapies available nowadays, ranging from pharmaceutical to hi-tech tailored solutions, remain ineffective due to their lack of precise real-time sleep tracking, in-time feedback on the therapies, and an ability to keep people asleep during the night. This paper aims to enhance the efficacy of such an intervention by proposing a novel sleep aid system that can sense multiple physiological signals continuously and simultaneously control auditory stimulation to evoke appropriate brain responses for fast sleep promotion. The system, a lightweight, comfortable, and user-friendly headband, employs a comprehensive set of algorithms and dedicated own-designed audio stimuli. Compared to the gold-standard device in 883 sleep studies on 377 subjects, the proposed system achieves (1) a strong correlation (0.89 ± 0.03) between the physiological signals acquired by ours and those from the gold-standard PSG, (2) an 87.8% agreement on automatic sleep scoring with the consensus scored by sleep technicians, and (3) a successful non-pharmacological real-time stimulation to shorten the duration of sleep falling by 24.1 min. Conclusively, our solution exceeds existing ones in promoting fast falling asleep, tracking sleep state accurately, and achieving high social acceptance through a reliable large-scale evaluation

Chemical composition and antibacterial property of Eclipta prostrata (L.) L.

Eclipta prostrata (L.) L. belonging to the Astearaceae family has been long used worldwide by various communities as a traditional medicine. We studied the antibacterial activity of different extracts from Eclipta prostrata (L.) L. against Aeromonas hydrophila, Aeromonas dhakensis, and Vibrio parahaemolyticus . The processing of this extract using repeated column and thin layer chromatographic techniques resulted in the isolation of three compounds including luteolin (1), kaempferol (2), and kaempferol-3-O-α-L-rhamnopyranoside (3), which were identified by NMR. Among them, kaempfreol-3-O-α-L-rhamnopyranoside was isolated for the first time and shows good antibacterial activity against Aeromonas hydrophila which is major pathogen for the aquaculture industry. The results demonstrate the beneficial effects of E. prostrata as an antimicrobial and bioactive compound for medicinal usages.

Targeting effect of folate on cancer cell through curcumin carrier nano-system

Folate receptor (FR) is well known for its overexpression on surface of various cancer cell lines, which is identical to normal tissue. Folic-based targeting drug delivery systems, therefore, are one of the most effective targeting carriers that effectively bind to FR up-regulated cancer cells. Curcumin was used both for labeling and chemotherapy. The materials were characterized and structurally confirmed by FT-IR spectra, fluorescent images and FE-SEM images. Bioassays were conducted on HeLa and HT29 cancer cell lines after 4 and 12 hours. Results show that folic acid significantly enhanced both targeting efficiency and internalization of curcumin to FR-expressing cancer cells