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Bioremediation with photosynthetic bacteria (PSB) is thought to be a promising removal method for hexavalent chromium [Cr(VI)]-containing wastewater. In the present study, Rhodobacter sphaeroides (R. sphaeroides) SC01 was used for the investigation of Cr(VI) removal in Cr(VI)-contaminated solution in the presence of melatonin. It was found that exogenous melatonin alleviated oxidative damage to R. sphaeroides SC01, increased Cr (VI) absorption capacity of cell membrane, and improved the reduction efficiency of Cr(VI) via the activation of chromate reductants. The results showed that melatonin could further promote the increase in Cr(VI) removal efficiency, reaching up to 97.8%. Furthermore, melatonin application resulted in 296.9%, 44.4%, and 69.7% upregulation of ascorbic acid (AsA), glutathione (GSH), and cysteine (Cys) relative to non-melatioin treated R. sphaeroides SC01 at 48 h. In addition, the resting cells, cell-free supernatants (CFS), and cell-free extracts (CFE) with melatonin had a higher Cr(VI) removal rate of 18.6%, 82.0%, and 15.2% compared with non-melatonin treated R. sphaeroides SC01. Fourier transform infrared spectroscopy (FTIR) revealed that melatonin increased the binding of Cr(III) with PO4

With the increasing demand of achieving comprehensive perception in every aspect of life, optical fibers have shown great potential in various applications due to their highly-sensitive, highly-integrated, flexible and real-time sensing capabilities. Among various sensing mechanisms, plasmonics based fiber-optic sensors provide remarkable sensitivity benefiting from their outstanding plasmon-matter interaction. Therefore, surface plasmon resonance (SPR) and localized SPR (LSPR)-based hybrid fiber-optic sensors have captured intensive research attention. Conventionally, SPR- or LSPR-based hybrid fiber-optic sensors rely on the resonant electron oscillations of thin metallic films or metallic nanoparticles functionalized on fiber surfaces. Coupled with the new advances in functional nanomaterials as well as fiber structure design and fabrication in recent years, new solutions continue to emerge to further improve the fiber-optic plasmonic sensors' performances in terms of sensitivity, specificity and biocompatibility. For instance, 2D materials like graphene can enhance the surface plasmon intensity at the metallic film surface due to the plasmon-matter interaction. Two-dimensional (2D) morphology of transition metal oxides can be doped with abundant free electrons to facilitate intrinsic plasmonics in visible or near-infrared frequencies, realizing exceptional field confinement and high sensitivity detection of analyte molecules. Gold nanoparticles capped with macrocyclic supramolecules show excellent selectivity to target biomolecules and ultralow limits of detection. Moreover, specially designed microstructured optical fibers are able to achieve high birefringence that can suppress the output inaccuracy induced by polarization crosstalk and meanwhile deliver promising sensitivity. This review aims to reveal and explore the frontiers of such hybrid plasmonic fiber-optic platforms in various sensing applications. Ministry of Education (MOE) National Research Foundation (NRF) Published version This work was supported in part by the Singapore Ministry of Education Academic Research Fund Tier 2 (MOE2019-T2-2-127), the Singapore Ministry of Education Academic Research Fund Tier 1 (MOE2019-T1-001-103 and MOE2019-T1-001-111) and the Singapore National Research Foundation Competitive Research Program (NRF-CRP18-2017-02). This work was also supported in part by Nanyang Technological University

With the increasing demand of achieving comprehensive perception in every aspect of life, optical fibers have shown great potential in various applications due to their highly sensitive, highly integrated, flexible and real-time sensing capabilities. Among various sensing mechanisms, plasmonics-based fiber-optic sensors provide remarkable sensitivity benefited from their outstanding plasmon–matter interaction. Therefore, surface plasmon resonance (SPR) and localized SPR (LSPR)-based fiber-optic sensors have captured intensive research efforts. Conventionally, SPR or LSPR-based fiber-optic sensors rely on the resonant electron oscillations of thin metallic films or metallic nanoparticles functionalized on fiber surface. Coupled with the new advances in functional nanomaterials as well as fiber structure design and fabrication in recent years, new solutions continue to emerge to further improve the fiber-optic plasmonic sensors performance in terms of sensitivity, specificity and biocompatibility. For instances, 2D materials like graphene can enhance the surface plasmon intensity at metallic film surface so as the plasmon–matter interaction. 2D morphology of transition metal oxides can be doped with abundant free electrons to facilitate intrinsic plasmonics in visible or near-infrared frequencies, realizing exceptional field confinement and highly sensitivity detection of analyte molecules. Gold nanoparticles capped with macrocyclic supramolecules show excellent selectivity to target biomolecules and ultralow limit of detection. Moreover, specially designed microstructured optical fibers are able to achieve high birefringence that can suppress the output inaccuracy induced by polarization crosstalk meanwhile deliver promising sensitivity. This chapter aims to reveal and explore the frontiers of such hybrid plasmonic fiber-optic platforms in various sensing applications.

Rhodiola rosea L., a worldwide botanical adaptogen, has been confirmed to possess protective effects of inflammatory injury for many diseases, including cardiovascular diseases, neurodegenerative diseases, diabetes, sepsis, and cancer. This paper is to review the recent clinical and experimental researches about the anti-inflammatory effects and the related mechanisms of Rhodiola rosea L. extracts, preparations, and the active compounds. From the collected information reviewed, this paper will provide the theoretical basis for its clinical application, and provide the evidences or guidance for future studies and medicinal exploitations of Rhodiola rosea L.

Two-dimensional (2D) plasmonic materials facilitate exceptional light–matter interaction and enable in situ plasmon resonance tunability. However, surface plasmons of these materials mainly locate intrinsically at the long wavelength range that are not accessible for practical applications. To address this fundamental challenge, transition metal oxides with atomically layered structure as well as free carriers doping capability have been considered as an alternative class of 2D plasmonic material for achieving tunable plasmonic properties in the visible and near-infrared range. Here, we synthesize few-layer α-MoO3 nanoflakes that are heavily doped with free electrons via H+ intercalation. The resultant substoichiometric MoO3–x nanoflakes provide strong plasmon resonance located at ∼735 nm. Moreover, the MoO3–x nanoflakes carrying positive charges show stable attachment to polyanions functionalized microfiber and good affinity to negatively charged biomolecules. Our experimental demonstration of fiber-optic biosensing platform provides a detection limit of bovine serum albumin as low as 1 pg/mL, and proves the feasibility and prospects of employing 2D MoO3–x plasmonic nanoflakes in highly integrated devices compliant with frequently used and cost-effective optical system. MOE (Min. of Education, S’pore) Accepted version

Plasmonics in conjunction with supramolecular chemistry brings new opportunities for biosensing. Modified with macrocyclic supramolecules, noble metal nanoparticles possess improved biocompatibility and highly efficient biomolecule immobilization and recognition via host-guest interaction. In this work, we synthesize high-quality and monodisperse β-cyclodextrin-capped gold nanoparticles (β-CD-capped AuNPs) in one-step facile and eco-friendly process, where β-CD functions as both reducing and capping agent. Integrated with a microfiber, the β-CD-capped AuNPs deliver promising localized surface plasmon resonance properties and ultralow detection limit of cholesterol molecules of 5 aM. The selective recognition of our proposed biosensor to cholesterol is further verified by interference study and analysis of real human serum samples. This study shows the bright prospects of supramolecular chemistry assisted plasmonics in achieving highly integrated and highly sensitive biosensing with extremely low consumption of clinical samples and small footprint. Ministry of Education (MOE) Nanyang Technological University Accepted version This work was supported in part by the Singapore Ministry of Education Academic Research Fund Tier 2 (MOE2015-T2-1-066 andMOE2015-T2-2-010), Singapore Ministry of Education Academic Research Fund Tier 1 (RG85/16), and Nanyang Technological University (Start-up grant M4081515: Lei Wei). We would like to acknowledge the FACTS (Facility for Analysis, Characterization, Testing and Simulations), Nanyang Technological University, Singapore, for the use of X-ray photoelectron spectroscopy.

Acute pancreatitis (AP) is a common acute abdominal disease with local or systemic inflammatory response, caused by abnormal activation of digestive enzymes. Baicalein has been shown to exert anti-inflammatory effects and to attenuate the pathological changes of AP. The aim of the research was to investigate the effects of baicalein on caerulein induced pancreatitis, and to elucidate the putative underlying mechanism. In this study, the therapeutic potential of baicalein and its mechanism were investigated in a caerulein-induced AP in vivo and in vitro model. The results indicate that baicalein treatment alleviates the caerulein-induced pathological damage in the pancreas. Baicalein decreased the expression level of pro-inflammatory cytokines and chemokines of the pancreas in caerulein treated mice and of isolated pancreatic acinar cells. Moreover, baicalein inhibited the expression of NF-κB p65 and the phosphorylation of p38 MAPK, ERK (extracellular signal-regulated kinase) as well as STAT 3, which indicates that baicalein exerts its anti-inflammatory effects via dampening the NF-κB, MAPK and STAT 3 signaling pathways. Together, this study provides experimental evidence for the clinical application of Scutellaria baicalensis Georgi or baicalein and indicates that baicalein may be a promising candidate for treatment of AP patients in the future.

Based on an input–output model, this paper calculates carbon emissions from household energy consumption in 2002, 2005, 2007, and 2010 between China and the USA. By a comparative analysis of the two countries, the results indicate the following: (1) In terms of the total household indirect carbon emissions, the USA has always been at a higher level than China. However, in recent years, China has presented a rapidly rising trend. In contrast, the USA appears to be experiencing a downward trend. (2) Indirect carbon emissions from USA household consumption mainly focus on Residence; Education, Culture, and Recreation; and Transport and Communications. By comparison, residence accounts for 50 % of China’s household indirect carbon emissions, and seven other sectors are much less than the USA (3) Although the number of China’s household facilities is growing rapidly, the carbon emissions remain at a relatively steady level. (4) In terms of the absolute value of the indirect carbon emissions from housing, the USA maintains a steady 400 million ton, while China increased from 150 to 500 million ton over 2002–2010.

We report an ultrasensitive gas refractive index (RI) sensor based on optical nanofiber couplers (ONCs). Theoretical analysis reveals that a dispersion turning point (DTP) exists when the diameter of the coupler is below 1000 nm. Leveraging this DTP, the gas RI sensitivity can be significantly improved to infinity. Then we experimentally demonstrate a DTP and achieve ultrahigh sensitivities of 46,470 nm/refractive index unit (RIU) and −45,550 nm/RIU around the DTP using an ONC with a diameter of 700 nm. More importantly, the unique twin dips/peaks interference characteristics around the DTP offers further enhancement on the sensitivity to 92,020 nm/RIU. The demonstrated sensor not only shows vast potential in ultrasensitive pressure sensing, acoustic sensing, gas sensing, and gas phase biomarker detection, but also provides a new tool for nonlinear optics, ultrafast optics, quantum optics, and ultracold atom optics. MOE (Min. of Education, S’pore) Accepted version

We report a simple and effective method to improve the sensitivities of fiber-optic modal interferometers with birefringence induced Vernier effect. Taking optical microfiber coupler as an example, we study the sensitivity enhancement of a microfiber coupler for refractive index (RI) sensing both theoretically and experimentally in the RI range of 1.33–1.35 where bioassays are typically carried out. Numerical results show that by tracing the wavelength shifts of dips in the envelope formed by the Vernier effect, RI sensitivities can be improved by almost one order of magnitude compared to the sensors without the Vernier effect. Then we experimentally achieve an ultra-high sensitivity of 35,823.3 nm/RIU using a microfiber coupler with a width of 3.2 μm. More importantly, we apply this ultra-sensitive sensor to detect human cardiac troponin, and a limit of detection of 1 ng/mL is achieved. This sensor is simple in configuration andcan serve as a bio-photonic platform for clinical diagnostics environmental monitoring and food safety. MOE (Min. of Education, S’pore) Accepted version

We present a systematic study on the spectral characteristics and ultrahigh sensitivity near the dispersion turning point (DTP) of optical microfiber couplers. Numerical simulations reveal that a DTP exists when the group effective refractive index (RI) difference between the even mode and the odd mode equals zero, where both ultrahigh positive RI sensitivities and negative RI sensitivities can be achieved. The position of the DTP is dependent on the coupler width, and it always exists over the surrounding RI (SRI) range of 1.333-1.41, which enables the ultrasensitive RI sensing in this wide RI range. Then, we studied the interference spectra characteristics around the DTP both theoretically and experimentally. We further experimentally demonstrate ultrahigh sensitivities of 59624 nm/refractive index unit (RIU) and -58470 nm/RIU around the SRI of 1.333 and 26999 nm/RIU and -29267 nm/RIU around the SRI of 1.35, respectively. High figure of merits of 4192 and 5280 are also achieved around the SRI of 1.333 and 1.35, respectively. Finally, utilizing the exceptional RI sensitivity, we demonstrate an ultrasensitive temperature sensor with a negative sensitivity of -15.23 nm/°C and a positive sensitivity of +16.78 nm/°C. MOE (Min. of Education, S’pore)

The structures with all real frequencies and static first hyperpolarizabilities ( β tot ) of a series of Li n @indeno[1,2- b ]fluorene ( n = 1–6) salts have been calculated by the second-order Moller–Plesset (MP2) theory. The results show that the Li-substituted effect can significantly enhance the β tot values of Li n @indeno[1,2- b ]fluorene compared with that of non-substituted molecule indeno[1,2- b ]fluorene. Especially, the β tot value (18640 a.u.) for Li 3 @indeno[1,2- b ]fluorene is the largest among all systems. According to the two-level model, the calculated f Δ μ /Δ E 3 values further explain the large second-order nonlinear optical (NLO) responses of Li n @indeno[1,2- b ]fluorene. In addition, the investigations on frequency-dependent first hyperpolarizabilities ( β ( ω )) show that the dispersion has less influence on the β ( ω ) values at low frequency area of all studied systems. It is our expectation that this work will be beneficial for further theoretical and experimental studies on the NLO properties of the lithium salts.

Density functional theory (DFT) calculations have been carried out to investigate the substituent effects and redox switching of the second-order nonlinear optical (NLO) properties of a series of the two-dimensional (2D) diaryl-substituted benzenes/carboranes. The calculated static first hyperpolarizabilities ( β tot ) of the neutral compounds increase with replacing the central benzene with carborane, extending the π-conjugated bridge, and introducing an electron donor into carbazole moiety. Particularly, a dramatic enhancement of the β tot values for the oxidized/reduced species is observed. The β tot values of one-electron oxidized/reduced species for compound 3 are 14 times and 32 times as large as that of its neutral counterpart, respectively. Furthermore, the electronic structure analysis shows that the carbazole performs as an oxidized center and the benzene/carborane performs as a reduced center. Interestingly, the second-order NLO responses are two-dimensional in characteristic with the large off-diagonal tensor values. This work not only provides more penetrating insight into the second-order NLO properties of 2D benzene/carborane-based compounds, but also obtains an efficient approach for devising redox-switchable NLO materials.

In this paper, a SOI-MEMS (silicon on insulator- micro electro mechanical system) pizeoresistive atmosphere pressure sensor is presented using anodic bonding. Differently from the prevailing fabrication process of silicon piezoresistive pressure sensor: the device layer monocrystalline of SOI silicon wafer is used as the strain gauge with a simple deep etching process; and the SiO2 layer of SOI silicon wafer as the insulator between strain gauge and substrate. The whole fabrication processes of the designed sensor are very simple, and can reduce the cost of sensor. The Pressure-Voltage characteristic test results suggest a precision within 0.14% in linear fitting. It is shown that the temperature coefficient is 2718ppm/°C from the Typical temperature curve of the pressure sensors.

The third-order nonlinear optical (NLO) properties of aromatic diimide molecules have been studied for the first time using density functional theory (DFT) with a finite field (FF). This study shows that the size of the aromatic core can affect the static second hyperpolarizability ( γ ). Increasing the number of benzenes along the longitudinal axis can effectively improve the γ values because the degree of charge transfer along the longitudinal direction increases, whereas an increase in the number of benzenes along the perpendicular axis does not enhance the γ values. Furthermore, the NLO responses of the reduced form radical anions 1 − , 5 − and 6 − , which were obtained by a reversible redox process, are discussed. The results show that the γ values of the radical anions are changed by the redox process. For the reduced form radical anion 6 − , the γ value is −1906.71 × 10 −36 esu, and its absolute value is ∼7.3 times larger than that of its neutral parent. An analysis of the BLA values demonstrates that the γ value is closely related to the conjugation of the aromatic core used in the redox process.

Men who have sex with men (MSM) are at risk for contracting hu- man immunodeficiency virus (HIV) infection. The objective of this study was to explore the characteristics and factors influencing unprotected anal intercourse (UAI) among MSM in Fuyang, China in order to develop an intervention program to prevent the spread of HIV infection among MSM. We conducted this cross sectional study among 413 MSM in 2013. Participants completed an interviewer- administered questionnaire and were tested for HIV and syphilis infections. Three hundred fifty of 413 subjects reported sexual activity with a male partner during the previous 6 months; of these 27(7.7%) had unprotected sex. Forty-four subjects had sex with a female partner during the previous 6 months; of these 25 (58.1%) had unprotected sex. The frequency of having unprotected sex with a female was significantly greater than with a male (χ2 = 84.52, p0.001). Multivariate logistic analysis showed education level (OR = 0.45, p = 0.003), length of time of current residence (OR = 0.47, p = 0.014), knowledge about HIV infection (OR = 0.09, p = 0.022) and integrated interventions (OR = 0.32, p0.001) were all significantly associated with UAI. High-risk sex behavior was common among the study population. A targeted interventions needs to be developed urgently.

We demonstrate an all-in-fiber optofluidic refractive index sensor based on a long-period grating in a side-channel photonic crystal fiber. We achieve fast liquid circulation and a sensitivity of ∼1042 nm/RIU over the range of 1.33∼1.36.

We experimentally demonstrate a side-polished optical fiber based graphene-on-gold biosensor. Single layer of graphene is deposited to improve the sensitivity in single-stranded DNA detection. Our proposed biosensor provides a detection limit lower than 1 pM.

We design a high-birefringent microstructured optical fiber for surface plasmon resonance sensor. Our proposed sensor provides birefringence as large as 4.2×10−4, which effectively reduces the measurement offset induced by polarization crosstalk.

An in-line optofluidic refractive index (RI) sensing platform is constructed by splicing a side-channel photonic crystal fiber (SC-PCF) with side-polished single mode fibers. A long-period grating (LPG) combined with an intermodal interference between LP01 and LP11 core modes is used for sensing the RI of the liquid in the side channel. The resonant dip shows a nonlinear wavelength shift with increasing RI over the measured range from 1.3330 to 1.3961. The RI response of this sensing platform for a low RI range of 1.3330-1.3780 is approximately linear, and exhibits a sensitivity of 1145 nm/RIU. Besides, the detection limit of our sensing scheme is improved by around one order of magnitude by introducing the intermodal interference. MOE (Min. of Education, S’pore)

A 2D material/metal hybrid plasmonic sensor is demonstrated by direct integration of graphene layer on gold-coated optical fiber. Both linear response to wide range ssDNA concentration from 1 × 10−12 to 10 × 10−6m and low detection limit of 1 × 10−12m are achieved. The resulting hybrid plasmonic sensor shows prospects of highly sensitive, highly integrated, and flexible sensing at fiber-optic length scale. MOE (Min. of Education, S’pore) Accepted version

Optical fiber based surface plasmon resonance (SPR) sensors are favored by their high sensitivity, compactness, remote and in situ sensing capabilities. Microstructured optical fibers (MOFs) possess microfluidic channels extended along the entire length right next to the fiber core, thereby enabling the infiltrated biochemical analyte to access the evanescent field of guided light. Since SPR can only be excited by the polarization vertical to metal surface, external perturbation could induce the polarization crosstalk in fiber core, thus leading to the instability of sensor output. Therefore for the first time we analyze how the large birefringence suppresses the impact of polarization crosstalk. We propose a high-birefringent MOF based SPR sensor with birefringence larger than 4 × 10−4 as well as easy infiltration of microfluidic analyte, while maintaining sensitivity as high as 3100 nm/RIU. MOE (Min. of Education, S’pore) Accepted version

The static first hyperpolarizabilities ( β vec ) of ligand L (N,N′-bis(4-methoxyphenyl)ethylenediimine) and its Pt(II) chelated complexes have been calculated by density functional theory (DFT) method. The results show that the β vec values of Pt(II) diimine complexes range from ∼4.2 to ∼198.8 times larger than that of ligand L , and the β vec values of Pt(II) complexes with coordinated atom O are larger than those of the corresponding complexes with S. Notably, the bimetallic complex 3a possesses the largest β vec value in the studied systems, ∼1498.86 × 10 −30 esu, which is ∼46.6, ∼30.5, and ∼3.6 times as large as those of complexes 1a , 2a and 3b , respectively. In addition, the dynamic first hyperpolarizabilities ( β vec ( ω )) of complex 1a are also calculated at the input photon energy from 0.1 to 1.8 eV. Our present work would be beneficial for further theoretical and experimental studies on large second-order nonlinear optical (NLO) responses of metal complexes.

Rhizoma coptidis, a broadly used traditional Chinese medicine, derives from the dried rhizomes of Coptis chinensis Franch, Coptis deltoidea C.Y. Cheng et Hsiao and Coptis teeta Wall. Quantitative determination of protoberberine alkaloids in R. coptidis is critical for controlling its quality. In this study, a rapid, simple and accurate quantitative (1)H NMR (qNMR) method was developed for simultaneous determination of berberine, jatrorrhizine, epiberberine, coptisine, palmatine and columbamine in R. coptidis from the three species. Method validation was performed in terms of selectivity, precision, repeatability, stability, accuracy, robustness and linearity. The average recoveries obtained were in the range of 96.9-102.4% for all the six alkaloids. In addition, the qNMR data were analyzed with analysis of variance (ANOVA), hierarchical clustering analysis (HCA) and principal component analysis (PCA), and the results showed that the contents of the active alkaloids have significant difference among the three species. Compared with the conventional HPLC approach, the proposed qNMR method was demonstrated to be a powerful tool for quantifying the six alkaloids due to its unique advantages of high robustness, rapid analysis time and no need of standard compounds for calibration curves preparation. These findings indicate that this method has potential as a reliable method for quality evaluation of herb medicines, especially for protoberberine alkaloid-containing ones.

In most fiber-optic gas sensing applications where the interested refractive index (RI) is ~1.0, the sensitivities are greatly constrained by the large mismatch between the effective RI of the guided mode and the RI of the surrounding gaseous medium. This fundamental challenge necessitates the development of a promising fiber-optic sensing mechanism with the outstanding RI sensitivity to achieve reliable remote gas sensors. In this work, we report a highly sensitive gas refractometer based on a tapered optical microfiber modal interferometer working at the dispersion turning point (DTP). First, we theoretically analyze the essential conditions to achieve the DTP, the spectral characteristics, and the sensing performance at the DTP. Results show that nonadiabatic tapered optical microfibers with diameters of 1.8-2.4 µm possess the DTPs in the near-infrared range and the RI sensitivities can be improved significantly around the DTPs. Second, we experimentally verify the ultrahigh RI sensitivity around the DTP using a nonadiabatic tapered optical microfiber with a waist diameter of ~2 μm. The experimental observations match well with the simulation results and our proposed gas refractometer provides an exceptional sensitivity as high as −69984.3 ± 2363.3 nm/RIU. MOE (Min. of Education, S’pore) Published version

Summary Neuroligins (NLs) are critical for synapse formation and function. NL3 R451C is an autism-associated mutation. NL3 R451C knockin (KI) mice exhibit autistic behavioral abnormalities, including social novelty deficits. However, neither the brain regions involved in social novelty nor the underlying mechanisms are clearly understood. Here, we found decreased excitability of fast-spiking interneurons and dysfunction of gamma oscillation in the medial prefrontal cortex (mPFC), which contributed to the social novelty deficit in the KI mice. Neuronal firing rates and phase-coding abnormalities were also detected in the KI mice during social interactions. Interestingly, optogenetic stimulation of parvalbumin interneurons in the mPFC at 40 Hz nested at 8 Hz positively modulated the social behaviors of mice and rescued the social novelty deficit in the KI mice. Our findings suggest that gamma oscillation dysfunction in the mPFC leads to social deficits in autism, and manipulating mPFC PV interneurons may reverse the deficits in adulthood.

This paper addresses the determination of aldehyde group (% of dialdehyde units) in dialdehyde cellulose (DACs) oxidized from bacterial cellulose (BC). With 4 determination methods, the oxidation degrees of DACs were studied: Automatic potential titration method through Schiff base reaction, Acid-base titration in Cannizzaro reaction, Metaperiodate consumption determination, and Measurement of amino nitrogen content in DAC derivatives. By comparing determination results of these methods, we found out the proper way suitable for this metaperiodate oxidation system of BC to measure the dialdehyde unit content of the DACs.

We experimentally demonstrate a magnetic field sensor based on long-period fiber grating (LPG) and magnetic fluid. Our proposed sensor possesses a high sensitivity of ∼0.154 dB/Gauss and a low measurement threshold of ∼7.4 Gauss.

The purpose of this study was retrospectively to analyze the peripheral blood lymphocyte subset distribution in patients with low or intermediate risk myelodysplastic syndromes (IPSS ≤ 1.0) and chronic aplastic anemia (CAA), and their hematological changes of peripheral blood after treatment, so as to understand differences and their relation with early treatment response. The lymphocyte subsets in peripheral blood of 67 patient with low or intermediate risk MDS (IPSS ≤ 1.0), 54 patients with CAA and 73 healthy individuals were analyzed by flow cytometry. The results showed that Th cells, Th/Ts ratio in peripheral blood of low or intermediate risk MDS were 42.94% ± 10.80% and 1.80% ± 0.99% respectively, and were significantly higher than those in control group; the CD16(+) CD56(+) cell ratio was 11.22% ± 7.97%, and was significantly lower than that in control group, the difference was statistically significant (P0.05); Ts cells and CD19(+) cell ratio in peripheral blood of CAA patients were 30.87% ± 9.11% and 16.98% ± 7.40% respectively, and were significantly higher than those in control group; CD16(+) CD56(+) cell ratio was 9.81% ± 7.00%, and was significantly lower than that in normal control group, and the difference was statistically significant (P0.05); while the Th cells and Th/Ts ratio in low or intermediate risk MDS group were significantly higher than those in CAA group, and the difference was statistically significant (P0.05). After treatment for 6 mouths, the HI-E and HI-N rates in CD19(+) cell normal group of low or intermediate risk MDS patients were 18.2% (4/22) and 13.6% (3/22), and were significantly lower than that in the increased group and decreased group. In Ts cell increased group HI-N rate was 15.4% (2/13), and was significantly lower than that in normal group and decreased group. In Th/Ts ratio decreased group HI-N rate was 14.3% (2/14), and was significantly lower than that in the increase group and normal group, the difference was statistically significant (P0.05). After treatment of CAA for 6 months, the effective rate for CD3(+) cells, Th cells, Th/Ts ratio in decreased group was 71.4% (5/7), 56.3% (9/16), 50.0% (10/20), and were significantly higher than those in increased and normal group, and the difference was statistically significant (P0.05). It is concluded that the peripheral blood lymphocyte subsets of low or intermediate risk MDS(IPSS score ≤ 1.0) and CAA are abnormal, and these lymphocyte subsets are related with hematologic changes after early response to treatment.

To explore the autophagy expression and examine its significance in chondrocytes in a degenerate model of human cervical vertebrae endplate.Cartilage endplates were obtained from 48 hospitalized patients with cervical vertebral fracture or dislocation at our hospital between February 2012 to August 2012. They were divided into cervical spondylosis group with cervical spondylotic myelopathy (n = 31) and control group (n = 17).Endplate chondrocytes were isolated by enzyme digestion and cultured in vitro. The cells were stained with toluidine blue and hematoxylin and eosin; laser scanning confocal microscope and monodansylcadaverine (MDC) were used to observe autophagy in endplate chondrocytes; reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of typeIIcollagen and aggrecan and Western blot for the protein of LC3.A degenerative cell model of human cervical endplate chondrocytes was established successfully in vitro. Compared with the common group, the cellular morphologies of degenerative group showed spindle changes. Autophagic body was stained with MDC.Intracellular and perinuclear LC3 protein was detected by laser confocal microscopy. Compared with the control group, the mRNA expressions of aggrecan (0.715 ± 0.194) and typeII collagen (0.628 ± 0.254) markedly decreased (0.845 ± 0.186,0.913 ± 0.254, P0.05) and LC3-II/LC3-I declined in cervical spondylosis group.Autophagy plays an important pathogenic role in the process of human cervical disc degeneration. And regulating its expression may improve disc degeneration in endplate cartilage cells.

The second-order nonlinear optical (NLO) properties of a series of Pt(II) dithienylethene (DTE) complexes possessing the reversible photochromic behavior have been investigated by density functional theory (DFT) combined with the analytic derivatives method. The results show that the calculated static first hyperpolarizabilities (βtot) of the open-ring and closed-ring systems significantly increase in the range of 2.1-4.5 times through strengthening of the electron-withdrawing ability of the substituent R (R = H, CF3, NO2) and an increase of the number of thiophene rings. Moreover, there is a large enhancement of the βtot values from the open-ring systems to the corresponding closed-ring systems. This efficient enhancement is attributed to the better delocalization of the π-electron system, the more obvious degree of charge transfer, and the larger f(os)/E(gm)(3) (f(os) is the oscillator strength, and E(gm) is the transition energy between the ground and the excited states) values in the closed forms according to the bond length alternation (BLA) and time-dependent density functional theory (TDDFT) calculations. In addition, the dispersion has less influence on the frequency-dependent first hyperpolarizabilities (βtot(ω)) of the studied systems at the low-frequency area ω (0.000-0.040 au). Our present work would be beneficial for further theoretical and experimental studies on large second-order NLO responses of metal complexes.

The unusual properties of Li-doped boron nitride nanomaterials have been paid further attention due to their wide applications in many promising fields. Here, density functional theory (DFT) calculations have been carried out to investigate the second-order nonlinear optical (NLO) properties of boron nitride nanocone (BNNC) and its Li-doped BNNC derivatives. The natural bond orbital charge, electron location function, localized orbital locator and frontier molecular orbital analysis offer further insights into the electron density of the Li-doped BNNC derivatives. The electron density is effectively bounded by the Li atom and its neighboring B atoms. The Li-doped BNNC molecules exhibit large static first hyperpolarizabilities (βtot) up to 1.19 × 103 a.u. for Li@2N-BNNC, 5.05 × 103 a.u. for Li@2B-BNNC, and 1.08 × 103 a.u. for Li@BN-BNNC, which are significantly larger than that of the non-doped BNNC (1.07 × 102 a.u.). The further investigations show that there are clearly dependencies of the first hyperpolarizabilities on the transition energies and oscillator strengths. Moreover, time-dependent DFT results show that the charge transfer from BNNC to Li atom becomes more pronounced as doping the Li atom to BNNC. It is also found that the frequency-dependent effect on the first hyperpolarizabilities is weak, which may be beneficial to experimentalists for designing Li-doped BNNC molecules with large NLO responses.

To investigate the expression and clinical significance of miR-155 in the peripheral blood CD4(+);T cells of patients with allergic asthma.The expression of pre-mature BIC transcript and its processed microRNA miR-155 in the CD4(+); T cells from 50 patients with allergic asthma and 20 healthy individuals were measured using real-time PCR. The correlation of miR-155 expression and the disease severity of asthma was analyzed. The ability of miR-155 to influence Th1/Th2 differentiation was examined in vitro.The expression of pre-mature BIC and miR-155 in the CD4(+); T cells of asthma patients significantly decreased compared to those in normal controls (P0.01). Furthermore, the expression of BIC in moderate and severe asthma patients was lower than that in normal controls (P0.05). Among mild, moderate, severe asthma patients, BIC expression showed no statistical significance, but miR-155 expression of severe asthma patients was lower than that in mild asthma patients (P0.05). The expression level of miR-155 was positively correlated to FEV1/pred(%) (P0.01). miR-155 over-expression was found to promote CD4(+); T cells to Th1 differentiation, while of miR-155 was found to induce CD4(+); T cells to Th2 differentiation.The decreased expression level of miR-155 is correlated to asthma disease severity. It is suggested miR-155 plays an important role in development of asthma.

To investigate the suppressive effect of gypenosides (Gyp) on murine leukemia L1210 cells.The growth inhabitation of murine leukemia L1210 cell was detected by MT assay. The production of reactive oxygen species and the change of mitochondrial membrane potential were detected by flow cytometry. The change of nuclear and DNA damage of murine leukemia L1210 cells were detected by DAPI staining and single cell gel electrophoresis.Gyp (100-500 microg/mL) inhibited the growth of murine leukemia L1210 cells. The concentration of Gyp (350 microg/mL) treated murine leukemia L1210 cells at different time points, the mitochondrial membrane potential decrease obviously. L1210 cells were treated with Gyp (350 microg/mL) for 4 h, the highest production of reactive oxygen species was induced. DNA damage were detected after Gyp (350 microg/mL) treated for 4, 12, 24 h. The change of nuclear was treated by Gyp (350 microg/mL) with time-dependent.Gypenosides has effects on cell viability, induce reactive oxygen species and decreases mitochondrial membrane potential, and can induce morphological changes and DNA damage.