Conventional Lamp Research Articles

Low-cost photolithography system for cell biology labs

Abstract Soft lithography, a tool widely applied in biology and life sciences with numerous applications, uses the soft molding of photolithography-generated master structures by polymers. The central part of a photolithography set-up is a mask-aligner mostly based on a high-pressure mercury lamp as an ultraviolet (UV) light source. This type of light source requires a high level of maintenance and shows a decreasing intensity over its lifetime, influencing the lithography outcome. In this paper, we present a low-cost, bench-top photolithography tool based on ninety-eight 375 nm light-emitting diodes (LEDs). With approx. 10 W, our presented lithography set-up requires only a fraction of the energy of a conventional lamp, the LEDs have a guaranteed lifetime of 1000 h, which becomes noticeable by at least 2.5 to 15 times more exposure cycles compared to a standard light source and with costs less than 850 C it is very affordable. Such a set-up is not only attractive to small academic and industrial fabrication facilities who want to enable work with the technology of photolithography and cannot afford a conventional set-up, but also microfluidic teaching laboratories and microfluidic research and development laboratories, in general, could benefit from this cost-effective alternative. With our self-built photolithography system, we were able to produce structures from 6 μm to 50 μm in height and 10 μm to 200 μm in width. As an optional feature, we present a scaled-down laminar flow hood to enable a dust-free working environment for the photolithography process.

LAMP-CRISPR-Cas12-based diagnostic platform for detection of Mycobacterium tuberculosis complex using real-time fluorescence or lateral flow test.

ACRISPR-based nucleic acid detection platform, termed LACD (loop-mediated isothermal amplification coupled with CRISPR-Cas12a-mediated diagnostic)has been developed. In the LACD system, the core primer used in conventional LAMP (forward inner primer or backward inner primer) was engineered to contain a PAM (protospacer adjacent motif) site (TTTT) at the linker region. As a result, the LAMP amplicons contained a specific PAM site for CRISPR-Cas12a recognition. At the CRISPR-mediated detection stage, the resulting LAMP products can activate the corresponding CRISPR-Cas12a effector upon the formation of the CRISPR-Cas12a/gRNA/target DNA complex. The single-strand DNA (ssDNA) reporter molecules are then rapidly cleaved due to the CRISPR-Cas12a's trans-enzyme activity. The ssDNA degradation can then be visualized on a lateral flow biosensor or measured by a real-time fluorescence instrument. Our LACD assay allows any target sequence to be detected (even targets which do not contain any PAM sites) as long as they met the design requirement for LAMP. The feasibility of the LACD methodology for nucleic acid detection was validated on the Mycobacterium tuberculosis complex (MTC). This proof-of-concept assay can be reconfigured to detect a variety of target sequences by redesigning the engineered LAMP primers.

Energy efficient photocatalytic activation of peroxymonosulfate by g-C3N4 under 400 nm LED irradiation for degradation of Acid Orange 7

Photocatalytic activation of peroxymonosulfate (PMS) by graphitic carbon nitride (g-C3N4) is emerging as a sulfate radical anion based advanced oxidation process (S-AOP) for degradation of organic pollutants. Importantly, photocatalytic activation of PMS by g-C3N4 is energy intensive as light irradiation requires high electrical energy. Here, we studied activation of PMS by g-C3N4 under 400 nm light emitting diode (LED) irradiation (g-C3N4/PMS/400-LED system) for degradation of Acid Orange 7 (AO7). LED array having optical emission maximum around 400 nm (FWHM = 16 nm), with electrical input power of 1.54 W (14 V and 110 mA) was used for irradiation. Pseudo-first order rate constant (kobs) value for degradation of AO7 by g-C3N4/PMS/400-LED system was determined to be 0.094 min−1. O2·-, SO4·- were revealed by radical scavenging and ESR investigations. kobs value in simulated ground and real tap water were determined to be 0.068 min−1 and 0.063 min−1, respectively. g-C3N4 was stable, and reused four times without any significant loss in its photocatalytic activity. Importantly, electrical energy per order (EEO) for degradation of AO7 by g-C3N4/PMS/400-LED system was determined to be 24.51 kWh m−3 order−1. In contrast, the EEO value for the degradation of AO7 by g-C3N4 activated PMS under visible light irradiation (>400 nm), using conventional xenon lamp, (g-C3N4/PMS/Vis-Xe system) was found to be very high as 2702 kWh m−3 order−1. Thus, the study highlights, LED irradiation source is promising for the development of energy efficient g-C3N4 photocatalytic activation of PMS for removal of organic pollutants.

UV Light Application as a Mean for Disinfection Applied in the Dairy Industry

Thermal treatment is the most popular decontamination technique used in the dairy industry to ensure food protection and prolong shelf life. But it also causes nutrient and aroma degradation, non-enzymatic browning, and organoleptic changes of dairy products. Non-thermal solutions, on the other hand, have been extensively explored in a response to rising market demand for more sustainable and safe goods. For a long time, the use of ultraviolet (UV) light in the food industry has held great promise. Irradiation with shortwave UV light has excellent germicidal properties, which can destroy a variety of microbial pathogens (for example bacteria, fungi, molds, yeasts, and viruses), at low maintenance and installation costs with minimal use of energy to preserve food without undesirable effects of heat treatment. The purpose of this review is to update the studies made on the possibilities of UV-C radiation while also addressing the essential processing factors involved in the disinfection. It also sheds light on the promise of UV light-emitting diodes (UV-LEDs) as a microbial inactivation alternative to conventional UV lamps.

GHG Emission Reduction Opportunities for Road Projects in the Emirate of Abu Dhabi: A Scenario Approach

The transportation sector is considered one of the driving forces behind the increased release of greenhouse gases (GHGs), with road transport being this sector’s main emissions contributor. In turn, efforts should be devoted to reducing emitted GHGs from this sector, and many such opportunities lie in the road transport life cycle. This paper investigated fourteen emission reduction scenarios based on the green initiatives issued by the Abu Dhabi Government. The explored measures are either related to road works and road municipal services or to traffic movement. The proposed measures were evaluated with reference to a baseline study previously reported by the authors for three different road projects in Abu Dhabi city. Findings reveal that normalized GHG emission reduction could be significantly reduced by (i) replacing 30% of internal combustion engine passenger cars with battery electric vehicles where the power demand is covered almost equally from nuclear and liquified natural gas (LNG) sources, (ii) reducing the number of passenger cars by 10%, and (iii) having one-fifth of passenger cars powered by LNG. A lesser significant reduction could be achieved by replacing conventional lamps with light-emitting diode (LED) lamps or by having one-fourth of lighting powered by solar energy. Even lesser reduction could be achieved by (i) replacing a portion of Portland cement with ground granulated blast furnace slag in concrete structures, (ii) fully utilizing treated sewage effluent for roadside-plant irrigation, (iii) reducing desalinated water used for roadside-plant irrigation by 20%, and (iv) increasing the number of higher efficiency passenger cars by 10%. Replacing hot-mix asphalt with warm-mix asphalt and using asphalt with a high stiffness modulus in the base layer results in low emission reduction. The use of 15% recycled asphalt or the use of 50% recycled aggregate in road construction has the least impact on emission reduction. When all explored scenarios were combined, an overall normalized GHG emissions reduction of 9–17% during the road project life cycle could be achieved.

UVA-LED Technology’s Treatment Efficiency and Cost in a Competitive Trial Applied to the Photo-Fenton Treatment of Landfill Leachate

The objective of this trial was to assess the application of UVA-LED technology as an alternative source of irradiation for photo-Fenton processes, aiming to reduce treatment costs and provide a feasible treatment for landfill leachate. An optimized combination of coagulation with ferric chloride followed by photo-Fenton treatment of landfill leachate was optimized. Three different radiation sources were tested, namely, two conventional high-pressure mercury-vapor immersion lamps (100 W and 450 W) and a custom-designed 8 W 365 nm UVA-LED lamp. The proposed treatment combination resulted in very efficient degradation of landfill leachate (COD removal = 90%). The coagulation pre-treatment removed about 70% of the COD and provided the necessary amount of iron for the subsequent photo-Fenton treatment, and it further favored this process by acidifying the solution to an optimum initial pH of 2.8. The 90% removal of color improved the penetration of radiation into the medium and by extension improved treatment efficiency. The faster the Fenton reactions were, as determined by the stoichiometric optimum set-up reaction condition of [H2O2]0/COD0 = 2.125, the better were the treatment results in terms of COD removal and biodegradability enhancement because the chances to scavenge oxidant agents were limited. The 100 W lamp was the least efficient one in terms of final effluent quality and operational cost figures. UVA-LED technology, assessed as the application of an 8 W 365 nm lamp, provided competitive results in terms of COD removal, biodegradability enhancement, and operational costs (35–55%) when compared to the performance of the 450 W conventional lamp.

DEVELOPMENT OF A MODEL LAMP BASED ON LED MATRIX

The work is devoted to the development of a lamp based on an LED matrix with varying chromaticity and illumination level. The following main components are used in the work: an addressable LED matrix WS2812b 1616 LED, Arduino Nano, a TTP223 touch button, a 5V 2A power supply. The basis for the lamp is a plumbing pipe with a diameter of 50 mm and a part of a pipe with a diameter of 40 mm; for the manufacture of a prototype, a matte shade from a conventional lamp was used. The working temperature of the matrix is from –25° to + 80° Celsius. Working at temperatures below – 25°, the tape may work poorly or not execute controller commands at all. For lighting effects and, in general, for the operation of the lamp, the code was written on the Arduino, and flashed into the Arduino Nano. The proposed lamp design can be used as decorative lighting for residential buildings.

Wireless UV-A LEDs-driven AOP in the treatment of agro-industrial wastewaters

A wireless UV-A LEDs lab-scale reactor powered by a resonant inductive coupling (RLC) system was built to maximize the UV photon absorption of agro-industrial wastewaters. The UV-A LEDs (λ = 365 nm) energy was supplied through a magnetic field generated inside of the photoreactor by induction coils placed on the external wall made of polyvinyl chloride. Immersing the light sources in the wastewater increases the photon transfer efficiency and the reaction rate. Maximum magnetic field and optical irradiance were obtained at 26.8 and 27.0 kHz, respectively.As proof-of-concept, elderberry wastewater (EW), olive washing wastewater (OWW) and white and red winery wastewaters (WWW and RWW) were treated combining the wireless UV-A LEDs with the Advanced Oxidation Process (AOP) - Fenton reagent.Fenton experiments were performed using [Fe2+] = 10 mg L−1, [H2O2] = 500 mg L−1, pH = 3 and a reaction time of 4 h. With EW a DOC removal of 35% (k = 0.0696 h−1) was achieved, whereas adding the wireless UV-A LEDs (f = 26.8 kHz) 53% was attained (k = 0.1722 h−1). The Electric Energy per Order (EEO) for the wireless UV-A LEDs consumption was calculated (EEO LEDs = 48.7 kWh m−3 order−1) and for all the remain equipment (air pump, RC box and power amplifier), EEO total = 495 kWh m−3 order−1. Experiments with OWW presented a DOC removal of 62% and a EEO LEDs = 40.5 kWh m−3 order−1; RWW shown 40% of DOC removal and a EEO LEDs = 68.4 kWh m−3 order−1, while with WWW 35% of DOC removal and a EEO LEDs = 79.8 kWh m−3 order−1 were obtained. This work shows that wireless UV-A LEDs can be a promising alternative to conventional UV lamps and wired LEDs in the treatment of real wastewaters. However, optimization of the induction system is still needed, as well as the number and wavelength of the LEDs (e.g. UV-C LEDs) to reduce the overall treatment costs.

Resident Perspectives 56–3

Resident Perspectives 56–3

Digital Loop-Mediated Isothermal Amplification-Based Absolute Methylation Quantification Revealed Hypermethylated DAPK1 in Cervical Cancer Patients.

The aberrant methylation of many genes has been reported to be associated with various carcinomas. Accurate detection of the methylation level could provide critical insights into the diagnostic analysis of diseases. Here, a sensitive HpaII-edited absolute droplet loop-mediated isothermal amplification (HEADLAMP) method based on methylation-sensitive restriction enzyme (MSRE) HpaII was developed for the digital quantification of DNA methylation. Methylation levels of the death-associated protein kinase 1 (DAPK1) gene that is associated with many cancers were studied using β-actin as an internal reference. DAPK1 (2.5 pM) with 0.01% methylation (250 aM) can be detected with the conventional HpaII-edited LAMP assay. Using HEADLAMP, as low as 1% methylation level can be distinguished with an estimated limit of detection of 5 aM (ca. 3 copies/μL). Moreover, HEADLAMP can detect low levels of methylated DAPK1 in normal L-02 cells, while the conventional assay cannot. Finally, HEADLAMP was applied to the detection of DAPK1 methylation in 20 clinical tissue samples, which revealed hypermethylated DAPK1 in cervical cancer patients. We envisage potential applications of this robust, specific, and sensitive HEADLAMP assay in epigenetic studies and early clinical diagnosis.

89 Effects of a Novel Heat Lamp Compared to Conventional Heat Lamps on Litter Performance

Abstract The objectives were to evaluate differences in productivity (mortality, number of pigs weaned and litter weights) and electricity usage between farrowing crates equipped with the HAVEN device or standard heat lamps. The HAVEN is a heat element designed to create a microclimate for newborn pigs. A total of 314 sows (Camborough; PIC, Hendersonville, TN) were initially allotted to the study in a randomized complete block design (RCBD) based on parity (P1, P2, P3+). Treatments consisted of control group (standard heat lamps) and treatment group (HAVEN device). Around d112 of gestation the sows were moved to the farrowing house and randomly allotted to the treatment. After farrow, litters were cross-fostered within treatment until 24-h after farrowing to equalize litter number to teat count. Litter size and weight were collected at the time of cross-fostering and at weaning. Sows had an ad libitum access to feed and water during lactation. Data were analyzed as an RCBD using the GLIMMIX procedure of SAS with litter as the experimental unit and block as a random effect. There was no significant difference (P > 0.05) between treatments on litter growth performance. However, there were significant differences (P < 0.05) between the Control and Haven groups on piglets mortality and removals (%). The Control group had a higher incidence of mortality when compared to the Haven group (11.42% vs. 9.06%, respectively). In addition, the Control group had a higher (P < 0.05) percentage of pigs removed compared to the Haven group (18.41% vs. 15.55%, respectively). Regarding electricity usage, on average the HAVEN device consumed 1.55 Wh/day compared to 2.41 Wh/day from the heat lamp. In conclusion, under the conditions of this trial the HAVEN provided production benefits reducing mortality and removals (%), and also potential savings in electricity.

Close-spaced evaporation of CaGe[formula omitted] films for scalable GeH film formation

Germanane (GeH) is an attractive layered material with potential applications in channel of field-effect transistors and can be topochemically synthesized from CaGe2. So far, the film growth method of CaGe2 has been limited to molecular beam epitaxy. In this study, we demonstrate CaGe2 epitaxial film growth on Ge(111) substrates at 675–800 °C by a scalable close-spaced evaporation method using a conventional lamp annealing furnace. Detailed investigation of the film structure by X-ray diffraction reveals that the CaGe2 films consist mainly of the metastable 2H polytype and of a minor amount of the stable 6R polytype. The CaGe2 film deposited at 800 °C is converted to GeH by low temperature HCl treatment while the other CaGe2 films transform to crystalline and nanocrystalline Ge. The reasons why only the CaGe2 film synthesized at 800 °C is converted to GeH is discussed in terms of the film microstructure observed by scanning electron microscopy. The absence of GeH in low-temperature deposited films after HCl treatment is attributed to the exfoliation of island crystals during HCl treatment. We thus show that close-spaced evaporation is a rapid and scalable method to prepare CaGe2 epitaxial films as a precursor of GeH films and that the roughness of CaGe2 should be improved for efficient conversion to GeH.

Prioritization of the effective factors in reducing energy consumption in a residential building using computer simulation

BACKGROUND AND OBJECTIVES: According to the latest energy balance sheets, the average energy consumption in the residential sector of Iran is about 41% of the total energy consumption in the country. Increasing the energy efficiency of buildings can decrease the annual energy consumption in the residential sector and, thereby, the energy costs of families. The objectives of this study were to evaluate and prioritize the effective factors in reducing the energy consumption in residential buildings in the north of Iran using the climatic conditions analysis.METHODS: In the first step, the amount of energy consumption in the cooling and heating section was estimated in the base conditions, and in the next step, the amount of energy consumption was calculated. The obtained results were compared with each other with the help of optimization strategies for energy consumption using the Design Builder software. Finally, a set of effective factors were determined to be involved in decreasing the energy consumption.FINDING: The results showed that application of the LED lamps instead of the conventional fluorescent lamps could decrease the energy consumption by 980.4 kWh. Moreover, changing the materials of the walls and ceiling, using the polyurethane foam insulation with the thickness of 20 mm, and using the double-glazed UPVC windows reduced the energy consumption by 770 kWh. Energy reduction of about 101.5 kWh was also obtained after external movable awning and internal blind.CONCLUSION: The most commonly used materials were analyzed by the Design Builder software. The analysis was done by integrating building architecture engineering (the best form of orientation and facade) based on the reasonable costs of consuming common materials in the area. The obtained results can be used for both evaluating the energy efficiency in residential buildings and producing a comfortable living environment in a moderate and humid climate.

Degradation of N-nitrosamines and 1,4-dioxane using vacuum ultraviolet irradiation (UV254+185 nm or UV172 nm)

Advanced oxidation processes (AOPs) play a vital role in attenuating contaminants of emerging concern (CECs) during potable water reuse. AOPs are conventionally performed by irradiating with a 254-nm low-pressure (LP) mercury-vapor (Hg) ultraviolet (UV) lamp along with chemical treatment. Compared with UV-C light treatment (200–280 nm), vacuum-UV (V-UV) light treatment (100–200 nm) is advantageous in terms of hydroxyl radical generation without the requirement for chemical treatment. This study assessed the potential of V-UV (172-nm Xe2 excimer or 185 + 254-nm LP-Hg) lamps on the destruction of two major CECs in potable water reuse, namely N-nitrosodimethylamine (NDMA) and 1,4-dioxane. Direct irradiation using UV254 nm or UV185+254 nm lamps achieved ≥94% removal of N-nitrosamines, including NDMA, at a UV dose of 900 mJ/cm2. In contrast, the Xe2 excimer lamp (UV172 nm) was less effective for N-nitrosamine removal, achieving up to 82% removal of NDMA. The removal of 1,4-dioxane by V-UV lamps at a UV dose of 900 mJ/cm2 reached 51% (UV172 nm) and 28% (UV185+254 nm), both of which results were superior to that obtained using a conventional UV254 nm lamp (10%). The addition of hydrogen peroxide during UV254 nm or UV185+254 nm irradiation was found to enhance the removal of 1,4-dioxane, while UV172 nm irradiation without hydrogen peroxide addition still exhibited greater efficiencies than those UV254 nm lamps-based AOPs. Overall, this study demonstrated that the removal of both NDMA and 1,4-dioxane can be successfully achieved using either a UV254+185 nm lamp with hydrogen peroxide or a UV172 nm Xe2 excimer lamp without hydrogen peroxide.

Novel supplemental heat source evaluation for swine farrowing stalls

The objectives of this study were to compare the production impact and energy usage between of a novel supplemental heat source (NSHS) and a conventional heat lamp (HL) in swine farrowing stalls. The NSHS evaluated has a parabolic shaped cover (provides heat to two creep areas) with clear curtains and an infrared heat source with proportional heat output control. Six farrowing turns in two farrowing rooms (24 farrowing stalls per room) were utilized in this study. The six NSHS (12 stall coverage) were randomly assigned to a farrowing stall for the duration of the study and HL assigned to the other 12 stalls. Piglets were weighed at 3 days and at 18 days of lactation using a litter scale and pre-weaning mortality was tracked using farm records. Energy usage was monitored using current sensors on each NSHS and HL energy was verified using a power meter. Data were collected on 113 NSHS and 101 HL litters and analyzed using a Mixed model in JMP 14. There was no statistical difference between the two treatments on ADG P>0.10, there was a tendency for significance for pre-wean mortality P=0.08; NSHS 9.67% (SE=0.82) and HL 12.04% (SE 0.87); and a significant difference was noted in the laid-on mortalities P< 0.05; NSHS 4.05% and HL 6.04%. There was a significant difference, P< 0.01, in the energy usage (NSHS 3.25 kWh d-1, HL6 kWh d-1). Overall the NSHS had a tendency to reduce pre-wean mortality with a significant reduction in laid-on mortalities and reduce energy usage, though no impact was noted on ADG of the piglets. 

Sunlight-induced C[sbnd]C bond formation reaction: Radical addition of alcohols/ethers/acetals to olefins

A sunlight-induced CC bond formation reactions upon the addition of alcohols/ethers/acetals to olefins proceeded efficiently using di-tert-butyl peroxide (DTBP). The reactions proceeded faster than many of the previously reported sunlight and many conventional lamp photolyses, typically in 3–4 h under irradiation with sunlight, in excellent yield using olefins bearing two electron withdrawing groups (EWGs) (product yield > 95 %) and in good to fair yield with olefins bearing one EWG. The yields observed for some products were ∼20 % higher than those obtained using a conventional Xe lamp as the light source, which was confirmed to be due to a light intensity effect. Gram-scale experiments showed similar yields to those observed in their corresponding small-scale experiments.

Photoluminescence studies and synthesis of KSrPO4:Ce3+, Eu3+ blue and orange-red emitting phosphor

The growing need for leftover fuels and the ecological effects of their use was intended to give life to the traditionally extended global superpower infrastructure. Conventional, reliable fluorescent and incandescent lamps emit energy in the form of either heat or gas discharge. Both principles are strongly owing to the greater energy fluctuations that arise related to higher temperatures with the greater shifts of Stokes concerned. Within this work, we recorded sulphate-based blue & Orange-red emitting phosphors for lamp industry applications prepared using updated wet chemical synthesis methods, because the production of superb materials with high and stable fluorescent and luminescent properties is necessary to achieve high emission and fine clarity in the innovation of display systems. Morphological and structural tests and validation of phase and quality were conducted using XRD and SEM. The photoluminescent emission spectra of KSrPO4:Ce3+, Eu3+ phosphors show a blue emission band centered at 440 nm and a orange-red emission band centered at 593 nm and 618 nm. Typically, the structure of the Ce3+ ion in the ground state is split into two levels such as 2F5/2 and 2F7/2, while the5d1 excited configuration is divided by the crystal playing field into 2 and 5 elements.

A phosphor converted RED light for automotive LED rear lamp and compliance with ECE light regulation

In conventional red color lighting LED lamp for vehicles are composed of red color lighting LED and additional transparent or red lenses. Generally red color lighting LED is based on the semiconductor materials as AlGaInP, AlGaAs or GaAsP. Such RED LEDs are mostly affected by temperature. As the temperature increases, the luminous flux droops sharply and lighting efficiency decreases accordingly. In addition, the light color changes due to the wavelength shift phenomenon. This makes the design for automotive ECE regulation for red light very demanding. In this study, it is intended to develop a high-efficiency RED LED light for automobile rear lamps with the phosphor-converted LEDs technology used the characteristics of blue light LED. The luminous flux droop affected by temperature change which is the most important parameter in vehicle lamp performance, is measured, and the compliance with the red light ECE regulation for automobiles is compared and evaluated. For measuring the optical properties, it was performed using the T3Ster TeraLED system. The PC RED LED chips for new development used blue LED based on InGaN (455 nm) and conventional RED LED chips are AllnGaP LEDs (614 nm, 620 nm). To optimize optical properties of PC RED LED, phosphor was applied in 5 grades according to concentration. The best optical properties of PC RED LED shows at the phosphor concentration of 40 %. The results have important implications for improving the performance of automotive red lamps.

Non-Invasive Colorimetric Magneto Loop-Mediated Isothermal Amplification (CM-LAMP) Method for Helicobacter pylori Detection.

More than half the world's population is thought to be infected with Helicobacter pylori. Although the majority of infected people are asymptomatic, H. pylori infection may cause gastric ulcers and deadly gastric cancer. Owing to the difficulty and invasiveness of current routine culture and diagnostic methods, a highly sensitive and specific noninvasive assay for H. pylori is of interest. This study highlighted the design and performance of a colorimetric magneto loop-mediated isothermal amplification (CM-LAMP) assay to detect H. pylori in spiked saliva samples. LF primers were coated on magnetic nanoparticles by carbodiimide-induced immobilization and functionally used for solidphase amplification. During the LAMP reaction at 66°C, biotin-tagged FIPs were incorporated into LAMP amplicons. The colorimetric signal developed after the addition of NeutrAvidin horseradish peroxidase conjugate (NA-HRP) and ABTS. None of the tested microorganisms, including closely related bacteria, was shown positive by the CM-LAMP assay except H. pylori isolates. This novel platform was highly specific and 100-fold more sensitive (40 CFU/ml or 0.2 CFU per reaction) than the PCR and conventional LAMP assays for the detection of H. pylori in spiked saliva. Our results demonstrated the feasibility of using this noninvasive molecular diagnostic test to detect H. pylori in saliva samples.

Design of Metal@Titanium Oxide Nano-heterodimers by Laser-Driven Photodeposition: Growth Mechanism and Modeling.

In order to circumvent the usual nucleation of randomly distributed tiny metallic dots photodeposited on TiO2 nanoparticles (NPs) induced by conventional UV lamps, we propose to synthesize well-controlled nanoheterodimers (NHDs) using lasers focused inside microfluidic reactors to strongly photoactivate redox reactions of active ions flowing along with nanoparticles in water solution. Since the flux of photons issued from a focused laser may be orders of magnitude higher than that reachable with classical lamps, the production of electron-hole pairs is tremendously increased, ensuring a large availability of carriers for the deposition and favoring the growth of a single metallic dot as compared to secondary nucleation events. We show that the growth of single silver or gold nanodots can be controlled by varying the beam intensity, the concentration of the metallic salt, and the flow velocity inside the microreactor. The confrontation to a build-in model of the metallic nanodot light-induced growth onto the surface of TiO2 NPs shows the emergence of a predictable "master behavior" on which individual growths obtained from various tested conditions do collapse. We also characterized the associated quantum yield. Eventually, we successfully confronted our model to growth data from the literature in the case of silver on TiO2 and gold on II-VI semiconducting NPs triggered by UV lamps. It shows that for the photosynthesis of NHDs the efficiency of the electron-hole pair production rate matters much more than the number of pairs produced and that the use of laser light can provide a photodeposition-based synthesis at the nanoscale.