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Seed analysis is a cornerstone in advancing agriculture, with vigor tests playing a critical role in evaluating the physiological quality of seeds. However, monitoring seed vigor over time poses a significant challenge for the seed industry, as traditional methods are time-consuming and heavily reliant on subjective human judgment. Concerning these limitations, optical-based techniques have emerged as promising alternatives. Among them, the biological laser speckle phenomenon, rooted in optical interferometry, has proven effective in sensitively detecting and monitoring activity levels in living tissues. Known as the biospeckle laser (BSL) technique, this approach offers reliable results in assessing seed vigor. The BSL technique stands out due to its simplicity, rapid analysis, objectivity, and potential for automation, making it a valuable tool for seed analysis. This paper explores the state-of-the-art application of the BSL technique for evaluating seed vigor, highlighting successful approaches, identifying current challenges, and outlining areas for future research. It delves into the experimental setup for seed illumination and discusses the associated image processing methods. Furthermore, the paper examines the numerical and graphical outcomes, underscoring the BSL technique's ability to carry out seed analysis by addressing the limitations of traditional methods and enhancing efficiency in the agricultural sector. [ABSTRACT FROM AUTHOR]

Copyright of Renewable Energy & Sustainable Development is the property of Arab Academy for Science, Technology & Maritime Transport and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The fungi Rhodotorula species are widespread airborne contaminants and are thought to be natural occupants of human skin, lungs, urine, and feces. Rhodotorula mucilaginosa, R. minuta, and R. glutinis are the three most prevalent species. Aim: The purpose of this study is to isolate Rhodotorula mucilaginosa from cow rumen fluid in the province of Mosul, as well as to determine how laser light irradiation affects the growth and morphological traits of this organism. Methods: From the fluid rumen of AL-restaki and AL-karadi cows, the Rhodotorula mucilaginosa was isolated. Using a traditional approach and the ID-Yst card system Vitek 2, isolated colonies were purified, recognized, and described. A semiconductor laser system with a power of 50 mW and a wavelength of 450 nm was used in the experiment to evaluate the light laser irradiation effects on the direct culture growth of Rhodotorula mucilaginosa under two light irradiation conditions of 30 and 60 minutes. Results: According to traditional methods and the ID-Yst card system Vitek 2, Rhodotorula mucilaginosa predominated 7/30 (23.3%), and these strains effectively thrived on medium containing dextrose agar as evidenced by the carotenoid pigments that gave their colonies a salmon-pink to coral-red hue. When compared to a control group where no laser was used, the impact of light laser irradiation was assessed 24 hours after the irradiation using a biomass (dry weight measuring yeast cell content in suspension) and microscopic analysis using Gram stain. The irregular shape of the cells and their link to one another were shown by macroscopic and microscopic examinations. The irradiated culture subculture on sabouraued dextrose agar and incubation at 37 C for 3 days demonstrated inhibited growth in 4/7 (57.1%) isolates. Also, there was no discernible difference between the control group and the Rhodotorula mucilaginosa biomass concentration under light irradiation circumstances (30 and 60 min). Conclusion: This was the first study identifying Rhodotorula mucilaginosa in Iraqi cow rumen fluid. [Open Vet J 2023; 13(6.000): 765-771]

Background: The fungi Rhodotorula species are widespread airborne contaminants and are thought to be natural occupants of human skin, lungs, urine, and feces. Therefore, Rhodotorula mucilaginosa, Rhodotorula minuta, and Rhodotorula glutinis are three of the most prevalent species. Aim: This study aims to isolate R. mucilaginosa from the rumen fluid of cows in the province of Mosul and to determine how laser light irradiation affects the growth and morphological traits of these Fungi. Methods: From the rumen fluid of AL-Restaki and AL-Karadi of cows, the R. mucilaginosa was isolated. Using the traditional approach and the ID-Yst card system Vitek 2. A semiconductor laser system with a power of 50 mW and a wavelength of 450 nm was used in the experiment to evaluate the light laser irradiation effects on the culture growth of R. mucilaginosa directly under two light irradiation conditions of 30 and 60 minutes. Results: According to traditional methods and the ID-Yst card system Vitek 2, R. mucilaginosa predominated 7/30 (23.3%), and these strains effectively grow on medium sabouraued dextrose agar as evidenced by the carotenoid pigments that gave their colonies a salmon-pink to coral-red. Compared with a control group where no laser was used, the impact of light laser irradiation was assessed 24 hours after the irradiation using biomass (dry weight measuring yeast cell content in suspension) and microscopic analysis using Gram stain. Microscopic examinations showed the irregular shape of the cells linked to one another. The irradiated subculture of on Sabouraued dextrose agar and incubation at 37°C for 3 days demonstrated inhibited growth in 4/7 (57.1%) isolates. In addition, there was no discernible difference vertically at p < 0.05 between the control group and the R. mucilaginosa biomass concentration under light irradiation circumstances (30 and 60 minutes). Conclusion: This study proved that R. mucilaginosa is found in the rumen fluid of cows. Also, the isolated R. mucilaginosa displayed sensitivity to laser irradiation lights, revealing the more significant topographical alterations of the cell structure that had happened, the irregular shape of the cells, and how they were connected as a result of evolution. [ABSTRACT FROM AUTHOR]

We demonstrate an innovative beam stabilization concept consisting of complementary metal-oxide semiconductor cameras and piezo actuators for a six-axis articulated ultrashort pulsed laser robot system. The beam stabilization system is fixed on robot axes 4 and 5. Moving robot axis 5 in an angular range between 0° and 90°, the laser beam position coupled to the actual robot position is monitored by two cameras integrated on robot axis 5 and used for laser beam characterization and model generation. A mathematical description and models generated with machine learning methods, namely, linear regression and neural network, are compared for predicting the beam position drift as a function of robot axis motion, where the neural network model shows a low prediction tolerance of about 7 pixels. In addition, a stand-alone time-triggered beam correction algorithm is developed and implemented on the system, which shows an excellent correction performance for large beam position drifts (below 500 pixels). [ABSTRACT FROM AUTHOR]

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

• 1-inch Yb x Sm 1-x OCa 4 (BO 3) 3 (Yb:SmCOB, x = 0.1, 0.2) crystals were grown by Bridgman method for the first time. Yb:SmCOB crystals have frequency doubling properties. The energy band and density of states of SmOCa 4 (BO 3) 3 (SmCOB) crystal were calculated by first-principles. Yb x Sm 1-x COB (x = 0.1, 0.2) crystals were grown by the Bridgman method for the first time. The purpose of this paper is to evaluate the application prospect of Yb:SmCOB crystal in quasi-parametric chirped pulse amplification (QPCPA) and frequency-doubling laser. The phase structure, thermal properties and optical properties of Yb:SmCOB were studied, and the density of states of SmCOB crystal was calculated by first-principles. The effective segregation coefficient K eff of Yb 0.1 Sm 0.9 COB and Yb 0.2 Sm 0.8 COB crystals are 0.89 and 0.88, respectively. The thermal diffusivity and thermal conductivity of Yb:SmCOB decrease with increasing temperature. The specific heat increases with the increase of temperature and eventually tends to be constant. The specific heat of Yb:SmCOB crystal is greater than 0.70 J/(g·K) at room temperature. The transmittance of Yb:SmCOB crystal reaches 87 % in the range of 500 ∼ 900 nm. With the increase of Yb3+ doping concentration, the UV absorption cut-off edge is red shifted. The frequency doubling emission peak of Yb:SmCOB crystal at 490 nm was measured by 980 nm laser. Yb:SmCOB has the characteristics of high transmittance and high specific heat, and has application potential in laser frequency doubling and QPCPA. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells isolated from the bone marrow have a great differentiation potential, being able to produce many cell lines, including osteoblasts. Osteoblasts have an important role in bone remodeling by actively participating in the maturation and mineralization of the extracellular matrix. The aim of this study was to determine the effect of laser application on the viability and proliferation of osteoblasts. Methods: Alveolar bone was harvested from 8 patients and placed into a culture medium to induce proliferation of mesenchymal stem cells. These were differentiated into osteoblasts in special conditions. The cells from each patient were split into two groups, one was treated using a 980 nm laser (1W output power, pulsed mode, 20 s, 50 mm distance) (laser "+") and the other one did not receive laser stimulation (laser "-"). Results: Using the confocal microscope, we determined that the cells from the laser "+" group were more active when compared to the laser "-" group. The number of cells in the laser "+" group was significantly greater compared to the laser "-" group as the ImageJ-NIH software showed (p = 0.0072). Conclusions: Laser application increases the proliferation rate of osteoblasts and intensifies their cellular activity. [ABSTRACT FROM AUTHOR]

Carbon-based materials such as graphene oxide are known as attractive candidate to improve the current optoelectronic and laser devices. In this work, neodymium nanoparticles doped zinc-tellurite glass coated with graphene oxide (GO) denoted as ZBTNd (NPs)-GO was prepared via low-cost melt-quenching method and simple spray coating method. The structural properties of the glass system had been carried out by using X-ray diffraction (XRD) and confirmed its amorphous structural arrangement with non-existence of crystalline structure. The TeO3 and BO3 structural units were found dominant in tellurite glass network as determined by Fourier transforms infrared spectrometer (FTIR). High number of oxygen functional groups and stacked of graphene layers on the glass surface were revealed by field scanning electron microscopy (FESEM) and Raman spectroscopy. The optical band gap energy values were found to decrease in the range of 2.665–2.405 eV along with dopant concentration. In the meantime, the refractive index values were found more than n > 2.00 and fall in the range of 2.12 to 2.20. The electronic polarization was calculated by using Lorentz-Lorentz equation and found in the range of 6.516 to 7.211 Å 3. Based on these results, the improvements on optical properties of tellurite glass have been made to be used in laser application. [ABSTRACT FROM AUTHOR]

The transmission characteristics of electromagnetic (EM) waves in a semicircular plasma filament layer generated by a femtosecond laser were studied in a wide frequency band including radar waves. We have focussed on the influence of plasma parameters and filament arrangement based on the diffraction and superposition theory of EM waves on the transmittance. A numerical simulation model using the current density convolution finite-difference time-domain method was constructed in a semicircularmultilayer filament structure, and the transmission characteristics of spherical EM waves were examined. The simulation results showed that in this semicircular structure, the transmittance was periodically changed at a frequency interval corresponding to the thickness of the filament channel. This phenomenon was more pronounced as the number of the filament layers increased. In the lower band (<30 GHz), there was little change in the transmittance according to layer-to-layer distance, but in the higher band (>30 GHz), it changed irregularly. On the contrary, for the electron number density, it changed regularly in the lower frequency and hardly changed in the higher frequency. When the number of layers was 3 or more, the transmittance became 0 at the centre of the channel, and a discontinuous interference pattern appeared more clearly as the frequency increased. [ABSTRACT FROM AUTHOR]

A novel concept for asteroid orbit control by restructuring asteroid surfaces to manipulate albedo and respective radiation pressure effects is introduced. The method itself is propellant-less allowing for prolonged operation and permitting the adaption and even reversing reflection changes. Microscopic restructuring of asteroid surface material allows further for asymmetric manipulation of reflective properties, which can be exploited for influencing orbit and attitude parameters. Asymmetric radiation pressures are well known for their ability to change the orbit of an asteroid through the Yarkovsky effect or rotational parameters by the YORP effect. It is shown that in the simplest form albedo manipulation of a solid surface asteroid can be achieved with a single spacecraft mission. A spacecraft will locally focus energy from a very low (pseudo-)orbit onto the asteroids surface. One technology candidate are CO2 laser systems, while other options exist. First, CO2 laser are used as conventional laser engravers to brighten mineralic and metallic surfaces. Second, CO2 laser cleaning systems are often used to remove silicate residue of industrial processes. It is calculated that an asteroid with a high albedo will experience significantly less Yarkovsky forces, resulting in reduced orbit drift and improved future predictability. Laser technology can further be exploited to create surface structures that represent an asymmetric saw tooth pattern (i.e. repeating sharp right triangles) by using femto second laser pulses or by an angled focal point. This asymmetric surface pattern leads to an angular dependent reflectivity, which can be exploited to create radiation pressure differences. When properly applied, countering spin-rate changes and rotation axis drift of the YORP effect is possible. A preliminary analysis indicates feasibility for a medium size probe equipped for laser treatment of Near Earth Object surfaces. • A novel method to manipulate asteroid albedo and radiation pressure is presented. • Laser use allows for quasi indefinite, flexible, repeatable albedo manipulation. • The list of laser treatable minerals includes silicates and natural dark stone. • A relative reduction of Yarkovsky forces of 60% is achieved reducing orbital drift. • Asteroid Bennu could be laser treated within 3 years by a conventional mission. [ABSTRACT FROM AUTHOR]

In this study, a system for measuring small-sized holes with a 17–21 mm diameter and 1000 mm length was constructed. The system comprises a laser interferometer to detect hole accuracy, a probe connected to a measurement bar, and an optical apparatus for detecting the probe attitude (position and inclination). The probe was supported by supporting pads. A steel workpiece with 18 -mm diameter and 800 mm length was used for the performance test. During the experiment, errors were found in terms of hole deviation and roundness profile. Further experiments, using new experimental apparatus and analysis, revealed the causes of errors: electrical noise that increased with time, two periodic stylus swings in the longitudinal direction of the hole per rotation of the measurement unit, and the excessive spring force pushing the tip of the stylus, causing a large frictional force with the hole wall, etc. If these errors are corrected, high accuracy in the measurement of hole deviation and roundness can be achieved. • A system for measuring deep holes is constructed: 18 mm diameter, 1000 mm length. • System comprises: laser interferometer, probe with corner cube prism, photo sensor. • Hole accuracy is measured: hole shape, hole deviation, roundness, and roughness. • Better measurement is performed with workpiece rotation than with probe rotation. [ABSTRACT FROM AUTHOR]

Aim: The aim of the study was to assess the awareness of laser dentistry among dentists in Chennai. Materials and Methods: This cross-sectional and descriptive study was carried out among dentists in Chennai. A questionnaire was designed and administered to dentists in Chennai. The questionnaire contained items related to use of laser in five different dental specialties: Oral surgery (8 items), endodontics (4 items), periodontics (4 items), operative dentistry (10 items), and pediatric dentistry/orthodontics (4 items), in addition to sometimes in laser production (4 items). (Advantage of laser, effect of laser on dental tissues, expenditure of laser treatment, biggest deterrent in practicing laser dentistry, types of laser to have in practice). The data were entered and analyzed statistically significant. Results: Dental lasers were introduced to dentistry in the mid-1960s. However, still, lasers are not being used to their full potential. The results of this survey clearly indicate that dental practitioners and students are interested in using laser technology. However, still, lasers are not being used to their full potential. The results of this survey clearly indicate that dental practitioners and students are interested in using laser technology. Furthermore, growing number of patients seeks out for the clinics where laser dentistry is practiced. There is a need for proper training regarding both theoretical and practical aspects of lasers. Conclusion: To conclude, this study education should be given during their college study programs on laser to increase its implementation in the field of dentistry. [ABSTRACT FROM AUTHOR]

• Nd3+ doped Bi 2 ZnB 2 O 7 crystals with different doping concentrations were grown using the Kyropoulos method. • The crystal structure and lattice parameters of Nd x Bi 2-x ZnB 2 O 7 were evaluated through powder X-ray diffraction. • The cw laser performance for the 2 at.% Nd: BZBO crystals was investigated for potential laser applications. Nd3+ doped Bi 2 ZnB 2 O 7 crystals (Nd x Bi 2-x ZnB 2 O 7) with varying doping concentrations were grown using the Kyropoulos method. The crystal structure of Nd x Bi 2-x ZnB 2 O 7 were evaluated through powder X-ray diffraction. The segregation coefficients of Nd3+ were determined by XRF to be 0.82 and 0.79 for 2 at.% and 5 at.% Nd: BZBO crystals, respectively. The full-width at half-maximum (FWHM) of the 2 at.% and 5 at.% Nd: BZBO crystals were 55.8 and 37.7 arcsec, respectively. The transmission, absorption and fluorescence spectra were measured. Moreover, the continuous-wave (CW) laser performance was investigated for the 2 at.% Nd: BZBO crystals. All the results indicated that the Nd:BZBO crystal chould potentially serve as a laser matrix. [ABSTRACT FROM AUTHOR]

This paper presents the results of the laser cleaning effects on textile samples with corroded metallic threads. In many museum collections, there are textile exhibits like uniforms, national costumes, flags and home textile, embroidered with metallic threads. Corrosion of metal threads is one of the most common problems that damage embroidered items. In the practice, the application of conventional cleaning methods rarely gives the expected results, and the implementation of laser technology was the next step for corrosion products cleaning. The Nd: YAG laser was used to clean the corrosion of embroidered items from a museum study collection. The effects on the laser irradiated zones were investigated by optical and SEM microscopy and the EDX analysis. The laser irradiation process parameters of the metal threads corrosion.

A table-top coherent diffractive imaging experiment on a sample with biological-like characteristics using a focused narrow-bandwidth high harmonic source around 30 nm is performed. An approach involving a beam stop and a new reconstruction algorithm to enhance the quality of reconstructed the image is described. [ABSTRACT FROM AUTHOR]

Glass frit encapsulation for laser-base sealing of the complex interiors results challenges for the electronics manufacturing process. The conventional frit packaging method relies on elevating thermal process by furnace where the package is heated to required temperature, hence limiting the use of temperature-sensitive materials and also creating problems in different packaging processes or multi-stage sealing products. In this paper, the benefits of combining novel laser-assist hermetical sealing and low temperature glass frit packaging are demonstrated and the technique offers a suitable and feasible solution. This frit of absorbent at specific laser wavelength is selected and applied as excellent contact with both large CTE range substrates. Glass frit composites consisting of a PbTiO ceramic and the rare earth NdO are evaluated for thermal properties and electrical characteristics. This developed glass frit hermetical sealing method achieves moisture durability, satisfying the enculturation of electronics-level. In this paper, we demonstrate successfully using laser to seal organic light emitting diode (OLED) via low melting temperature glass frit. [ABSTRACT FROM AUTHOR]

An addition of Eu3+ ions in Borate glasses (7TiO 2 + 3Al 2 O 3 + (60−x)B 2 O 3 + xEu 2 O 3 + 5LiCO 3 + 25SrCO 3) (where x = 0.05, 0.10, 0.15, and 0.20 mol%) and Boro-phosphate glasses (40B 2 O 3 + 3Al 2 O 3 + (10−x)P 2 O 5 + xEu 2 O 3 + 7ZnO + 5LiCO 3 + 10H 6 NO 4 P + 25SrCO 3) (where x = 0.10 and 0.20 mol%) containing heavy metals, alkali, and alkaline were prepared using a conventional melt quenching technique. The complementary study of the FT-IR and FT-Raman spectroscopic studies proposed the conversion of BO 3 ⇔ BO 4 in the borate glass network, and the exchange of the PO 3 ⇔ PO 2 in the boro-phosphate glass network by increasing the Eu3+ ion concentration. The optical characteristics including absorption, linear refractive index (n), Urbach energy (E u), direct and indirect band gap energies of the prepared glasses were examined and discussed. Judd-Ofelt (JO) theory was used to determine radiative spectroscopic properties such as radiative transition probability (A R), luminescence branching ratio (β R) and stimulated emission cross-section (σ P E). Theoretically, the optical gain parameter and gain bandwidth were calculated, which shows their vital role in laser applications. Using CIE chromaticity coordinates, the reddish orange light emission was observed as a proportion of the increase in Eu3+ ions concentration in both glass networks. The measured colour coordinates were utilised to evaluate the correlated colour temperature (CCT), colour purity (P c), and excitation purity (P e) of the studied glasses. [Display omitted] • Eu3+ ions in the range of 0.05–0.20 mol% are successfully doped in borate and boro-phosphate glass matrices and studied. • The η of BPEu(0.10) is 87.8% and σ p E of BEu (0.20) is 11 × 10−22 cm2 is higher than other prepared glasses. • All the spectroscopic studies confirm the prepared glasses could be suitable for optoelectronic device applications. [ABSTRACT FROM AUTHOR]

This contribution discusses technical and growth relevant aspects of using laser techniques for weed control. The research on thermal weed control via laser first focused on the interaction of laser beams and weed plants. Due to preliminary studies, a CO2-laser was selected for further studies with regard to the process factors laser energy, laser spot area, coverage of the weeds meristem, weed species (Amaranthus retroflexus), and weed growth stage. Thereby, the laser damage was modeled in order to control the necessary laser output power online. Furthermore, the beam positioning leading to an effective damaging of the weeds was investigated and a test device was designed. With the aid of contemporary image processing algorithms for weed recognition and meristem determination, a laser and servo-motor control was developed. Most of the studies presented in this paper were part of the project “Investigations on laser light affected weed control of juvenile plants with the aid of image processing” funded by the Deutsche Forschungsgemeinschaft.

This paper describes a relative localization system used to achieve the navigation of a convoy of robotic units in indoor environments. This positioning system is carried out fusing two sensorial sources: (a) an odometric system and (b) a laser scanner together with artificial landmarks located on top of the units. The laser source allows one to compensate the cumulative error inherent to dead-reckoning; whereas the odometry source provides less pose uncertainty in short trajectories. A discrete Extended Kalman Filter, customized for this application, is used in order to accomplish this aim under real time constraints. Different experimental results with a convoy of Pioneer P3-DX units tracking non-linear trajectories are shown. The paper shows that a simple setup based on low cost laser range systems and robot built-in odometry sensors is able to give a high degree of robustness and accuracy to the relative localization problem of convoy units for indoor applications.

Summary Interferometry was used together with the conventional microplate resazurin assay to evaluate the antimycobacterial properties of essential oil (EO) from fruits of Pterodon emarginatus and also of rifampicin against Mycobacterium bovis. The aim of this work is not only to investigate the potential antimycobacterial activity of this EO, but also to test the interferometric method in comparison with the conventional one. The Minimum Inhibitory Concentration (MIC) values of EO (625 μg/mL) and rifampicin (4 ng/mL) were firstly identified with the microplate method. These values were used as parameters in Drug Susceptibility Tests (DST) with interferometry. The interferometry confirmed the MIC value of EO identified with microplate and revealed a bacteriostatic behavior for this concentration. At 2500 μg/mL interferometry revealed bactericidal activity of the EO. Mycobacterial growth was detected with interferometry at 4 ng/mL of rifampicin and even at higher concentrations. One important difference is that the interferometric method preserves the sample, so that after weeks of quantitative observation, the sample can be used to evaluate the bactericidal activity of the tested drug. [ABSTRACT FROM AUTHOR]

The quality inspection process is usually carried out after first processing of the raw materials such as cutting and milling. This is because the parts of the materials to be used are unidentified until they have been trimmed. If the quality of the material is assessed before the laser process, then the energy and efforts wasted on defected materials can be saved. We proposed a new production scheme that can achieve quantitative quality inspection prior to primitive laser cutting by means of three-dimensional (3-D) vision measurement. First, the 3-D model of the object is reconstructed by the stereo cameras, from which the spatial cutting path is derived. Second, collaborating with another rear camera, the 3-D cutting path is reprojected to both the frontal and rear views of the object and thus generates the regions-of-interest (ROIs) for surface defect analysis. An accurate visual guided laser process and reprojection-based ROI segmentation are enabled by a global-optimization--based trinocular calibration method. The prototype system was built and tested with the processing of raw duck feathers for high-quality badminton shuttle manufacture. Incorporating with a two-dimensional wavelet-decomposition--based defect analysis algorithm, both the geometrical and appearance features of the raw feathers are quantified before they are cut into small patches, which result in fully automatic feather cutting and sorting. [ABSTRACT FROM AUTHOR]

A modified spatial-temporal speckle correlation technique for operational assessment of structural changes in muscle tissues after slaughtering is considered. Coefficient of biological activity as a quantitative indicator of structural changes of biochemical processes in biological tissues is proposed. The experimental results have shown that this coefficient properly evaluates the biological activity of pig and chicken muscle tissue samples. Studying the degradation processes in muscle tissue during long-time storage in a refrigerator by measuring the spatial-temporal dynamics of biospeckle patterns is carried out. The reduction of the bioactivity level of refrigerated muscle tissue samples connected with the initiation of muscle fiber cracks and ruptures, reduction of sarcomeres, nuclei deformation, nuclear chromatin diminishing, and destruction of mitochondria is analyzed. [ABSTRACT FROM AUTHOR]

The article presents the possibility to diagnose a machine – physical object – in particular diesel engine. Studies were organized to demonstrate the possibility to use LDV (Laser Doppler Vibrometry) in the fundamental (diagnostic) studies. The object tested is a common model of modern diesel engine, frequently used in currently available vehicles. This paper describes the results of researches performed based on the displacement and the velocity, which indicates usefulness of each of these variables. In addition, the article presents older type of vibration detection system uses in vehicles (based on accelerometers) and conditioning path of the received vibroacoustic signal to become complete and fully useful diagnostic information. [ABSTRACT FROM AUTHOR]

We experimentally study the pressure dependent high-order harmonic generation in a semi-infinite gas cell with different absorbing gaseous media in order to reveal the influence of absorption in the high harmonic generation (HHG) process. Theoretical fits to the experimental results allow us to measure the absorption cross-section of the harmonics and to investigate the pressure independent phase mismatches. Our findings provide a better understanding about HHG in absorbing media and show that a sharp and intense harmonic spectrum can be generated as phase-matched and absorption-limited in a long interaction length geometry. [ABSTRACT FROM AUTHOR]

Double-exposure holographic interferometry is used to investigate the response of the human femur, with and without fracture, subjected to mechanical forces. The femur without fracture experienced uniform tension in the lateral side and uniform compression in the medial side. Fractured femurs stabilized by different internal fixators were investigated and significant differences in the dynamics were observed. The fractured femur stabilized by a plate and screws experienced greater bending in the upper portion than in the lower portion of the fracture. In the fractured femur stabilized by an intramedullary nail, the load was absorbed completely by the lower portion of the fracture.

Microscopic deformations on the surface of a circular diaphragm were measured using double exposure holographic interferometry and Fourier transform method (FTM). The three-dimensional surface deformations were successfully visualized by applying FTM to holographic interferogram analysis. The minimum surface displacement measured was 0.317 µm. This was calibrated via the Michelson interferometry technique.

Impulsive noise is a major problem that seriously degrades the performance of self-mixing interferometry (SMI). A new method to rectify this issue is proposed. First, an outlier detection approach is employed to detect the data samples corrupted by the impulsive noise, and then the SMI signal waveform is rectified by means of least square (LS) curve fitting. The results show that the proposed method can effectively remove the impulsive noise without introducing distortion to the original waveform and thus lead to improvement in the performance of an SMI system. [ABSTRACT FROM AUTHOR]

Optoelectronics, area which enjoys global strategy for the coming decades, covers an extremely wide field, with vague borders. It comprises everything and anything related to the instrumentation that emits, modulates, detects and transmits the light. Optoelectronics and photonics encompass multiple technologies underpinning numerous applications from consumer, entertainment and computing, homeland security, industrial markets and to defence. Among the research activities dedicated to developing new materials for optoelectronics and optoelectronic devices for nurturing them through different applications, in INOE we are focused on using lasers beam in the various fields of optoelectronics. Our research targets many areas related to the quality and improvement of human life: from ground to air, human to environmental health, economics to cultural heritage, we develop laser-oriented applications. [ABSTRACT FROM AUTHOR]

Abstract: Reactive sintering of YAG based ceramics is generally performed under high vacuum in graphite-free furnaces in order to guarantee the elimination of pores and absence of any contamination. An alternative densification technique is the field assisted process such as spark plasma sintering and microwave sintering. Both of these methods are characterized by very fast heating rates, low sintering temperatures and short sintering times. The microwave sintering process is different from electric resistance heating since heat is generated in the bulk of the powder compact through electromagnetic radiation absorption and creates within its body uniform temperature distribution. Microwave sintering of laser ceramics is advantageously distinguished by the absence of any elements having high temperature such as electric heaters or dies which materials can contaminate the sintered parts. In addition, the inverse temperature distribution that exists within the body under volumetric microwave heating is favorable for elimination of porosity. Microwave sintering of Yb:YAG samples were tested and the obtained results are presented. The samples were sintered on a gyrotron-based system operating at a frequency of 24GHz with microwave power up to 6kW. Reactive sintering of YAG doped with 1.0, 5.0, and 9.8at.% Yb2O3 was performed in different temperature–time regimes. The microstructure and the optical transmittance of the obtained samples were compared to those of samples obtained by conventional high vacuum sintering. [Copyright &y& Elsevier]

Abstract: Thin material laser perforation improves the flexibility and quality of materials such as tipping paper, medicated sticking plaster and breathable plastic film for storage. Perforation processing requires reliable, high speed, robust and adaptable optoelectronic systems to provide controllable permeability and flexibility in thin materials. This article provides descriptions on the design and performance of a new laser perforation system developed to meet such stringent requirements. This system is applicable for on-line thin material perforation. The optoelectronics include a continuous wave CO2 laser whose beam can be modulated into sequences of pulsed laser beams by a mechanical chopper. The focusing characteristics of a real laser beam in the perforation system have been investigated. This allowed laser beams to be focused on the moving thin material to be perforated and adaptable software control to provide the desired pattern distribution of the circular holes perforated on this material. A galvanometer scanner system allows sequential scanning of pulsed laser beams. This unique optoelectronic, mechanical and dedicated embedded control system has been designed and implemented to synchronize the actions of mechanical choppers, galvanometer scanners and the movement characteristics of the thin material. A practical implementation of the sticking plaster and tipping paper laser perforation system has been completed and successfully tested. Results show for example that circular holes with two geometrical distribution patterns are achievable, and unique patterns of perforation can be designed to discourage counterfeiting. [Copyright &y& Elsevier]