Comparison of immune responses and intestinal flora in epicutaneously sensitized BALB/c or C57BL/6 mouse models of food allergy

Cutaneous exposure to food allergens through a disrupted skin barrier is recognized as an important cause of food allergy,and the cutaneous sensitized mouse model has been established to investigate relevant allergic disorders.However,the role of different genetic backgrounds of mice on immune responses to food allergens upon epicutaneous sensitization is largely unknown.In this study,two strains of mice,i.e.,the BALB/c and C57BL/6 mice,were epicutaneously sensitized with ovalbumin on atopic dermatitis(AD)-like skin lesions,followed by intragastric challenge to induce IgE-mediated food allergy.Allergic outcomes were measured as clinical signs,specific antibodies and cytokines,and immune cell subpopulations,as well as changes in intestinal barrier function and gut microbiota.Results showed that both strains of mice exhibited typical food-allergic symptoms with a Th2-skewed response.The C57BL/6 mice,rather than the BALB/c mice,were fitter for establishing an epicutaneously sensitized model of food allergy since a stronger Th2-biased response and severer disruptions in the intestinal barrier and gut homeostasis were observed.This study provides knowledge for selecting an appropriate mouse model to study food-allergic responses associated with AD-like skin lesions and highlights the role of genetic variations in the immune mechanism underlying pathogenesis of food allergy.

Antarctic red algae in dye-sensitized photoelectrochemical cells for water splitting

Phycoerythrin extracted from Antarctic red seaweeds shows promising characteristics to be applied as an anode sensitizer in water-splitting photoelectrochemical cells.Under light irradiation and using an LED lamp,the red-colored protein shows an interesting ability to profit the incident light,as confirmed by the presence of oxygen bubbles next to the electrode surface without applying any external potential.Our results showed that the addition of iodide is helpful to allow the regeneration of the dye;nevertheless,oxygen evolution is not favored.Thermodynamics analysis of the involved semi-reactions is also helpful to understand the observed results.The exploration of Antarctic resources offers then an alternative for the development of green energies,with a particular focus on their use as sensitizers to profit from the sunlight in water-splitting as well as in photovoltaic devices.

Effects of acupuncture on serotonin,histamine,substance P,and tryptase levels at sensitized points in model rats with knee osteoarthritis

Objective:To elucidate the differences in manual acupuncture effectiveness at sensitized points by investigating the mechanisms of local skin action at different sensitization points in rats with knee osteoarthritis(KOA).Methods:Forty SpragueeDawley rats were equally divided into control,model(1 mg of mono-iodoacetate into the right knee joint cavity),sham operation,manual acupuncture at right Tianjing acupoint(MAR-SJ 10),and left SJ 10 groups.Safranine-O and fast green staining were used to assess the modeling.The morphological and functional changes in mast cells(MCs)were assessed during acupoint sensitization using toluidine blue and immunofluorescence staining.The levels of serotonin,histamine,substance P(SP),and tryptase at skin acupoints and serum levels of IL-β,IL-6,and TNF-αwere detected using ELISA.Results:After 14 days of treatment,the number of MCs and their degranulation rates were statistically higher in the model group than in the control group(both P<0.001).After applying acupuncture,the levels of 5-HT,HA,and SP at skin acupoints were lower than those in the model group(all P<0.05),and tryptase level was higher(both P<0.05).Tryptase level was higher on the skin at the MAL-SJ 10 acupoint than that on the MAR-SJ 10 acupoint(P=0.004).Compared with the model group,the serum levels of IL-1β,IL-6,and TNF-αin the MAR-SJ 10 and MAL-SJ 10 groups were lower(all P<0.05).Conclusion:Acupuncture at KOA-sensitized acupoints mitigates joint injury in KOA rats and may bidi-rectionally regulate local MCs of these acupoints.This finding not only enhances the reference value of sensitizing points in clinical diagnosis and treatment,but also contributes to the understanding of the biological mechanisms underlying acupuncture intervention at sensitizing points.

Ultra‑High Sensitivity Anisotropic Piezoelectric Sensors for Structural Health Monitoring and Robotic Perception

Monitoring minuscule mechanical signals,both in magnitude and direction,is imperative in many application scenarios,e.g.,structural health monitoring and robotic sensing systems.However,the piezoelectric sensor struggles to satisfy the requirements for directional recognition due to the limited piezoelectric coefficient matrix,and achieving sensitivity for detecting micrometer-scale deformations is also challenging.Herein,we develop a vector sensor composed of lead zirconate titanate-electronic grade glass fiber composite filaments with oriented arrangement,capable of detecting minute anisotropic deformations.The as-prepared vector sensor can identify the deformation directions even when subjected to an unprecedented nominal strain of 0.06%,thereby enabling its utility in accurately discerning the 5μm-height wrinkles in thin films and in monitoring human pulse waves.The ultra-high sensitivity is attributed to the formation of porous ferroelectret and the efficient load transfer efficiency of continuous lead zirconate titanate phase.Additionally,when integrated with machine learning techniques,the sensor’s capability to recognize multi-signals enables it to differentiate between 10 types of fine textures with 100%accuracy.The structural design in piezoelectric devices enables a more comprehensive perception of mechanical stimuli,offering a novel perspective for enhancing recognition accuracy.

Low-concentration atropine(0.01%)on quantitative contrast sensitivity function in Chinese children with myopia

AIM:To investigate the effect of 0.01%low-concentration atropine(LA)on quantitative contrast sensitivity function(qCSF)in children with myopia.METHODS:This paired case-control study included 90 eyes of 58 children who were sex-,age-,and refractionmatched and equally divided into two groups:the 0.01%LA group had undergone 6mo use of daily 0.01%atropine and control group was naïve to LA.Routine ophthalmic examinations and qCSF test without refractive correction were performed.Two groups were compared in monocular and binocular qCSF parameters,including the area under logCSF,CSF acuity,and contrast sensitivity(CS)at 1.0-18.0 cycle per degree(cpd).RESULTS:In the monocular comparison,the CSF acuity of the LA group was significantly higher than that of the control group(7.58±5.51 vs 6.37±4.22 cpd,P<0.05).The subgroup analysis showed that in the 6-9y group,CSF acuity was significantly higher in the LA group than the control group(8.76±6.19 vs 6.54±4.25 cpd,P<0.05),and in the Female group,low refraction sphere group,and high refraction cylinder group,the CS at high spatial frequencies(12.0 and 18.0 cpd)were significantly higher in the LA group than in the control group(all P<0.05).In the binocular test,CSF acuity and CS at 12.0 cpd were significantly higher in the LA group than in the control group(10.95±7.00 vs 8.65±5.12 cpd;0.17±0.33 vs 0.06±0.16,respectively;both P<0.05).CONCLUSION:Use of LA may result in improved CS in children with early onset myopia.

Cumulative effects of stress-sensitivity factors on depressive symptoms and suicide risk:A prospective study

BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity variables affect MDD.We hypothesize that high-level trait-and state-related stress-sensitivity factors may have different cumulative effects on the clinical symptoms and follow-up outcomes of MDD.AIM To investigate how stress-sensitivity factors added up and affected MDD clinical symptoms and follow-up results.METHODS In this prospective study,281 MDD patients were enrolled from a tertiary care setting.High-level stress-sensitivity factors were classified as trait anxiety,state anxiety,perceived stress,and neuroticism,with a total score in the top quartile of the research cohort.The cumulative effects of stress-sensitivity factors on cognitive dysfunction,disability and functional impairment,suicide risk,and depressive and anxiety symptoms were examined using an analysis of variance with linear trend analysis.Correlations were investigated further using multiple regression analysis.RESULTS Regarding high-level stress-sensitivity factors,53.40%of patients had at least one at baseline,and 29.61%had two or more.Four high-level stress-sensitivity components had significant cumulative impacts on MDD symptoms at baseline(all P<0.001).Perceived stress predicted the greatest effect sizes of state-related factors on depressive symptoms(partialη^(2)=0.153;standardizedβ=0.195;P<0.05).The follow-up outcomes were significantly impacted only by the high-level trait-related components,mainly when it came to depressive symptoms and suicide risk,which were predicted by trait anxiety and neuroticism,respectively(partialη^(2)=0.204 and 0.156;standardizedβ=0.247 and 0.392;P<0.05).CONCLUSION To enhance outcomes of MDD and lower the suicide risk,screening for stress-sensitivity factors and considering multifaceted measures,mainly focusing on trait-related ones,should be addressed clinically.

Spatiotemporal variation and influencing factors of desertification sensitivity on the Qinghai-Xizang Plateau,China

Due to irrational human activities and extreme climate,the Qinghai-Xizang Plateau,China,faces a serious threat of desertification.Desertification has a detrimental effect on the ecological environment and socioeconomic development.In this study,the desertification sensitivity index(DSI)model was established by integrating the spatial distance model and environmentally sensitive area index evaluation method,and then the model was used to quantitatively analyze the spatial and temporal characteristics of desertification sensitivity of the Qinghai-Xizang Plateau from 1990 to 2020.The results revealed that:(1)a general increasing tendency from southeast to northwest was identified in the spatial distribution of desertification sensitivity.The low-sensitivity areas were mostly concentrated in the Hengduan and Nyaingqêntanglha mountains and surrounding forest and meadow areas.The high-sensitivity areas were located mainly in the Kunlun and Altun mountains and surrounding decertified areas.The center of gravity of all types of desertification-sensitive areas moved to the northwest,and the desertification sensitivity showed a decreasing trend as a whole;(2)the area of highly sensitive desertification areas decreased by 8.37%,with extreme sensitivity being the largest change among the sensitivity types.The desertification sensitivity transfer was characterized by a greater shift to lower sensitivity levels(24.56%)than to higher levels(2.03%),which demonstrated a declining trend;(3)since 1990,the change in desertification sensitivity has been dominated by the stabilizing type Ⅰ(29.30%),with the area of continuously increasing desertification sensitivity accounting for only 1.10%,indicating that the management of desertification has achieved positive results in recent years;and(4)natural factors have had a more significant impact on desertification sensitivity on the Xizang Plateau,whereas socioeconomic factors affected only localized areas.The main factors influencing desertification sensitivity were vegetation drought tolerance and aridity index.Studying spatiotemporal variations in desertification sensitivity and its influencing factors can provide a scientific foundation for developing strategies to control desertification on the Qinghai-Xizang Plateau.Dividing different desertification-sensitive areas on the basis of these patterns of change can facilitate the formulation of more targeted management and protection measures,contributing to ecological construction and sustainable economic development in the area.

Role of octamer transcription factor 4 in proliferation,migration,drug sensitivity,and stemness maintenance of pancreatic cancer cells

BACKGROUND Pancreatic cancer(PC)is one of the most aggressive malignancies characterized by rapid progression and poor prognosis.The involvement of cancer stem cells(CSCs)and Octamer transcription factor 4(OCT4)in PC pathobiology is being increasingly recognized.AIM To investigate the role of OCT4 in pancreatic CSCs and its effect on PC cell prolif-eration,migration,drug sensitivity,and stemness maintenance.METHODS We analyzed OCT4 and CD133 expression in PC tissues and cell lines.BxPC-3 cells were used to assess the effects of OCT4 modulation on cellular behavior.Proliferation,migration,and stemness of BxPC-3 cells were evaluated,and the PI3K/AKT/mTOR pathway was examined to gain mechanistic insights.RESULTS OCT4 and CD133 were significantly overexpressed in PC tissues.OCT4 mo-dulation altered BxPC-3 cell proliferation,invasion,and stemness,with OCT4 overexpression(OV-OCT4)enhancing these properties and OCT4 interference decreasing them.OV-OCT4 activated the PI3K/AKT/mTOR pathway,which correlated with an increase in PC stem cells(PCSC).CONCLUSION OCT4 plays a crucial role in PCSCs by influencing the aggressiveness and drug resistance of PC cells,thus presenting itself as a potential therapeutic target.

Sensitivity Analysis of Structural Dynamic Behavior Based on the Sparse Polynomial Chaos Expansion and Material Point Method

This paper presents a framework for constructing surrogate models for sensitivity analysis of structural dynamics behavior.Physical models involving deformation,such as collisions,vibrations,and penetration,are devel-oped using the material point method.To reduce the computational cost of Monte Carlo simulations,response surface models are created as surrogate models for the material point system to approximate its dynamic behavior.An adaptive randomized greedy algorithm is employed to construct a sparse polynomial chaos expansion model with a fixed order,effectively balancing the accuracy and computational efficiency of the surrogate model.Based on the sparse polynomial chaos expansion,sensitivity analysis is conducted using the global finite difference and Sobol methods.Several examples of structural dynamics are provided to demonstrate the effectiveness of the proposed method in addressing structural dynamics problems.

Correlation between diabetic peripheral neuropathy and thyroid hormone sensitivity in elderly patients with type 2 diabetes mellitus

BACKGROUND Diabetic peripheral neuropathy(DPN)is a common complication of type 2 diabetes mellitus(T2DM),significantly affecting patients’quality of life and imposing a substantial economic burden.Recent studies have highlighted the role of thyroid hormones in diabetes complications,particularly in elderly patients with T2DM.However,the relationship between thyroid hormone sensitivity and DPN remains unclear.AIM To investigate the correlation between thyroid hormone sensitivity and DPN in elderly patients with T2DM.METHODS In a cohort of 256 elderly patients with T2DM,propensity score matching was used to balance age,sex,and diabetes duration.Clinical data were collected to calculate thyroid hormone sensitivity and analyze its correlation with DPN.A random forest model was used to evaluate the diagnostic value of free triiodothyronine/free thyroxine(FT_(3)/FT_(4))for DPN.RESULTS Patients with DPN had a lower FT_(3)/FT_(4) ratio[(0.302±0.053)vs(0.316±0.049),P=0.040].Quartile stratification showed decreasing DPN prevalence with higher FT_(3)/FT_(4) ratios.Spearman’s correlation analysis showed that a lower FT_(3)/FT_(4) ratio was associated with higher glycated hemoglobin,fasting blood glucose,reduced nerve conduction velocity,and electrical skin conductance.Logistic regression indicated a positive relationship between the median FT_(3)/FT_(4) ratio and bilateral foot electrochemical skin conductance[odds ratio(OR):1.019;95%CI:1.005-1.034;P=0.007]and sural nerve sensory amplitude(OR:1.310;95%CI:1.008-1.703;P=0.043).Receiver operating characteristic analysis using a random forest model showed that incorporating FT_(3)/FT_(4) improved predictive performance for DPN,with an area under the curve of 0.74,sensitivity of 0.79,specificity of 0.64,and accuracy of 0.77.CONCLUSION In elderly patients with T2DM with euthyroidism,a lower FT_(3)/FT_(4) ratio is correlated with increased DPN incidence,affecting both large and small nerve fibers.FT_(3)/FT_(4) is an effective predictor of DPN.

Synthesis and Characterization of Novel Schiff Base for Enhanced Dye-Sensitized Solar Cell Photo-Response Mechanism

The efficient photo-response mechanism is one of the key factors in the commercialization of dye-sensitized solar cells in a bid to satisfy renewable energy demands. Progress in green technology has put solar energy on the front burner as a provider of clean and affordable energy for a sustainable society. We report the synthesis of a novel Schiff base with optical transparency in the visible and near IR region of the solar spectrum that can find application in the DSSCs photo-response mechanism. The synthesized crystal exhibited features that could handle some of the shortcomings of dye-sensitized solar cells which include wide band solar spectrum absorption and capability for swift charge transfer within the photoelectrodes. The synthesized Schiff base was characterized using x-ray diffractometer, UV/Visible spectrometer, Frontier transmission infrared spectrometer and conductometer. XRD data revealed the grown crystal to have an average crystallite size of 2.08 nm with average microstrain value of about 269.43. The FT-IR recorded transmission wave ѵ (CO) at 1207.7 cm−1 while dominant wave occurred at ѵ1654.9 and ѵ1592.3 cm−1 relating to ѵ (CN) stretching and ѵ (NH) bending respectively were observed. The IR spectrum revealed the bonding species and a probable molecular structure of 2,6-bis(benzyloxy)pyridine. The UV/Visible spectra convoluted to maximum peak within the near IR region suggesting that 2,6-bis(benzyloxy)pyridine can absorb both the visible and near IR region while its electrical conductivity was determined to be 4.58 µS/cm. The obtained result of the present study revealed promising characteristics of a photosensitizer that can find application in the photo-response mechanism of DSSCs.

近红外无创血糖浓度的Label Sensitivity算法和支持向量机回归

近红外光谱分析技术在生物医学工程领域具有广阔应用前景。无创且持续性地测量能实时监控人体血糖水平,给糖尿病患者带来极大便利性、提高生存质量、降低糖尿病并发症发生率具有很大的社会效益。无创血糖监测的想法提出较早,但仍然存在预测精度低、预测值与标签值相关性不高等难点,至今没有达到临床要求。近年来,光谱检测技术发展迅猛且机器学习技术在智能信息处理方面具有明显优势,两者结合可以有效提高人体无创血糖医学监测模型的精度和普适性。提出了一种标签敏感度算法(LS),并结合支持向量机方法建立了人体血糖含量预测模型。使用近红外光谱仪采集了4名志愿者食指处动态血液光谱数据(每名志愿者28组数据),并使用多元散射矫正(MSC)方法消除了部分光散射的影响。考虑血糖对不同波长光的吸收有差异,提出了基于血糖浓度标签差的特征波长挑选方法,并构建了标签敏感度支持向量机(LSSVR)预测模型。设计实验,对比该模型与偏最小二乘回归(PLSR)和区分度支持向量机(FSSVR)算法。结果表明,LS算法的最佳特征波长数为32,经特征波长选择后的LSSVR表现最佳,其均方误差降低至0.02 mmol·L^(-1),明显优于全谱段PLSR模型,血糖浓度的预测值与标签值的相关系数提升至99.8%,预测值全部位于可容许误差的克拉克网格A区内。LSSVR模型的优异表现为早日实现血糖的无创监测提供了新思路。

Photodegradation of methyl orange by BiOI-sensitized TiO_2

BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The photocatalytic activities of the catalysts were evaluated for the degradation of methyl orange (MO) solution under UV and visible light irradiation. The effects of catalyst amount, initial pH value, initial concentration of MO, as well as KI amount were investigated. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst was also tested. It is shown that BiOI sensitization enhances the photocatalytic activities of TiO2. With BiOI content increasing, the photocatalytic activities of BiOI/TiO2 under UV and visible light irradiation first increase, reaching a maximum around BiOI content of 1.7%, and then decrease with further increasing BiOI content. The 1.7% BiOI/TiO2 catalyst obviously exhibits much higher visible light photocatalytic activity than P25, and its UV light photocatalytic activity is slightly higher than that of P25. Under the conditions of a catalytic dose of 1.5 g.L-1, initial pH of 3.0, initial MO concentration of 20 mg.L-1, UV power of 300 W, and air flow rate of 0.8 L.min-1, complete degradatio is achieved within 60 min. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst is highly reliable.

Characterization of Passive Films Formed on As-received and Sensitized AISI 304 Stainless Steel

The current research of corrosion resistance of stainless steels mainly focuses on characterization of the passive films by point defect mode and mixed-conduction model. The corrosion resistance of the passive films formed on asreceived and sensitized AISI304 stainless steel in borate bu er solution were evaluated in this paper. The degree of sensitization and corrosion resistance of AISI304 stainless steels was evaluated by double loop electrochemical potentiodynamic reactivation and electrochemical impedance spectroscopy. The passive films formed on the stainless steels were studied by XPS technique. It was found that as-received specimen had higher pitting corrosion potential and corrosion resistance than sensitized one. The Mott-Schottky results showed that sensitized stainless steel had more defects in the passive film than as-received one. The compositions of the passive films were mainly Cr and Fe oxides according to XPS results.

A Dye-sensitized Nanocrystalline Solid State Photovoltaic Cell

A new type of dye-sensitized nanocrystalline solid state photovoltaic cell based on the wide band gap n-TiO2/p-CuI heterojunction was fabricated. Tetra-carboxyphenyl porphyrine (TPP-(COOH)(4)), squarylium cyanine derivative (SQ-(CH2),(SO3Py+)-Py-.) and ruthenium bipyridyl complex (RuL2(NCS)(2)) were used as photosensitizers. Larger photocurrents and photovoltages were shown in the cell sensitized by ruthenium bipyridyl complex and can be further increased by intercalation of a TiO2 thin underlayer.

Titania Nanostructures for Dye-sensitized Solar Cells

Titania is one kind of important materials, which has been extensively investigated because of its unique electronic and optical properties. Research efforts have largely focused on the optimization of the dye,but recently the titania nanostructures electrode itself has attracted more attention. It has been shown that particle size, shape, crystallinity, surface morphology, and chemistry of the TiO_2 material are key parameters which should be controlled for optimized performance of the solar cell. Titania can be found in different shape of nanostructures including mesoporous, nanotube, nanowire, and nanorod structures. The present article reviews the structural, synthesis, electronic, and optical properties of TiO_2 nanostructures for dye sensitized solar cells.

Kinetics study of ultrafast electron transfer from sensitized dyes to silver halide microcrystals

Spectral sensitization micromechanism of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr microcrystals with different dye concentrations is studied by using picosecond time-resolved fluorescence spectroscopy, and the dependences of electron transfer and spectral efficiency sensitization on different conditions are analysed in detail, With the steady spectroscopy, the wavelengths of absorption and fluorescence of J-aggregate adsorbed on AgBr microcrystals are found to shift to red relative to dye monomer. The spectrum of fluorescence has a red shift relative to the absorption peak. With the time-resolved fluorescence spectroscopy, the fluorescence decay curves of cyanine dyes J-aggregate adsorbed on the tabular and cubic AgBr grains are found to be fitted well by a double-exponential decay function. The fitting curves consist of a fast and a slow component. Because of the large amplitude of the fast component, this fast decay should be attributable mainly to the electron transfer from J-aggregate of dye to a conduction band of AgBr.

Role of steroid maintenance in sensitized kidney transplant recipients

AIM: To evaluate whether there is a threshold sensitization level beyond which benefits of chronic steroid maintenance(CSM) emerge. METHODS: Using Organ Procurement and Transplant Network/United Network of Organ Sharing database, we compared the adjusted graft and patient survivals for CSM vs early steroid withdrawal(ESW) among patients who underwent deceased-donor kidney(DDK) transplantation from 2000 to 2008 who were stratified by peak-panel reactive antibody(peak-PRA) titers(0%-30%, 31%-60% and > 60%). All patients received perioperative induction therapy and maintenance immunosuppression based on calcineurin inhibitor(CNI) and mycophenolate mofetil(MMF).RESULTS: The study included 42851 patients. In the 0%-30% peak-PRA class, adjusted over-all graft-failure(HR 1.11, 95%CI: 1.03-1.20, P = 0.009) and patientdeath(HR 1.29, 95%CI: 1.16-1.43, P < 0.001) risks were higher and death-censored graft-failure risk(HR 1.06, 95%CI: 0.98-1.14, P = 0.16) similar for CSM(n = 25218) vs ESW(n = 7399). Over-all(HR 1.04, 95%CI: 0.85-1.28, P = 0.70) and death-censored(HR 0.97, 95%CI: 0.78-1.21, P = 0.81) graft-failure risks were similar and patient-death risk(HR 1.39, 95%CI: 1.03-1.87, P = 0.03) higher for CSM(n = 3495) vs ESW(n = 850) groups for 31%-60% peak-PRA class. In the > 60% peak-PRA class, adjusted overall graft-failure(HR 0.90, 95%CI: 0.76-1.08, P = 0.25) and patientdeath(HR 0.92, 95%CI: 0.71-1.17, P = 0.47) risks were similar and death-censored graft-failure risk lower(HR 0.84, 95%CI: 0.71-0.99, P = 0.04) for CSM(n = 4966)vs ESW(n = 923).CONCLUSION: In DDK transplant recipients who underwent perioperative induction and CNI/MMF maintenance, CSM appears to be associated with increased risk for death with functioning graft in minimally-sensitized patients and improved death-censored graft survival in highly-sensitized patients.

200-nm long TiO_2 nanorod arrays for efficient solid-state Pb S quantum dot-sensitized solar cellsR

To ensure the infiltration of spiro-OMeTAD into the quantum dot-sensitized photoanode and to consider the limit of the hole diffusion length in the spiro-OMeTAD layer, a rutile TiO2 nanorod array with a length of 200 nm, a diameter of 20 nm and an areal density of 720 ram 2 was successfully prepared using a hydrothermal method with an aqueous-grown solution of 38 mM titanium isopropoxide and 6 M hydrochloric acid at 170 ℃ for 75 min. PbS quantum dots were deposited by a spin coating-assisted successive ionic layer adsorption and reaction （spin-SILAR）, and all solid-state PbS quantum dot-sensitized TiO2 nanorod array solar cells were fabricated using spiro-OMeTAD as electrolytes. The results revealed that the average crystal size of PbS quantum dots was -78 nm using Pb（NO3）2 as the lead source and remain unchanged with the increase of the number of spin-SILAR cycles. The all solid-state PbS quantum dot-sensitized TiO2 nanorod array solar cells with spin-SILAR cycle numbers of 20, 30 and 40 achieved the photoelectric conversion efficiencies of 3.74%, 4.12% and 3.11%, respectively, under AM 1.5 G illumination （100 mW/cm2）.

CdS Quantum Dots-sensitized TiO_2 Nanotube Arrays for Solar Cells

CdS quantum dots（QDs） sensitized TiO2 nanotube arrays photoelectrodes were investigated for their photovoltaic performance of quantum dots-sensitized solar cells. The highly ordered TiO2 nanotube arrays（TNAs） were synthesized on Ti foils by anodic oxidation method. Then CdS quantum dots were deposited onto the TiO2 nanotube arrays by successive ionic layer absorption and reaction（SILAR） method to serve as the sensitizers. Cd（NO3）2 and Na2S were used as the precursor materials of Cd＋ and S2- ions, respectively. It is found that the CdS QDs sensitizer may significantly increase the light response of TiO2 nanotube arrays. With increasing CdS QDs deposition cycles, the visible light response increases. Maximum photocurrent was obtained for the QDs that have an absorption peak at about 500 nm. Under AM 1.5 G illuminations（100 mW cm^-2）, a 4.85 mA/cm^2 short circuit current density was achieved, and the maximium energy conversion efficiency of the asprepared CdS QDs-sensitized TNAs solar cells was obtained as high as 0.81% at five SILAR cycles.