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Diabetes mellitus (DM) and its associated complications, including diabetic kidney disease, neuropathy, and retinopathy, impose significant challenges on healthcare systems due to their high morbidity, mortality, and associated costs. Existing treatments often yield unsatisfactory clinical outcomes, underscoring the need for innovative approaches to mitigate debilitating effects on patients' health-related quality of life. Photobiomodulation (PBM) is a non-invasive treatment that utilizes specific wavelengths of light in the treatment of various medical complications associated with DM. The specific wavelength used during PBM is critical in determining the therapeutic outcomes for managing diabetic complications. This paper aimed to explore the therapeutic potential of PBM in the management of diabetic complications, focusing on blue, red, and near-infrared (NIR) wavelengths. Relevant literature from Google Scholar, PubMed and ClinicalTrials databases from inception to date was searched using the keywords 'photobiomodulation', 'diabetes', 'diabetic complications', 'wound healing', 'neuropathy', 'retinopathy', and 'chronic wounds'. Red and NIR wavelengths are commonly used for a range of complications, while blue light has primarily been explored for treating diabetic wounds due to its antimicrobial nature. PBM treatment parameters for the same diabetic complication vary across clinical trials and preclinical research, with minimal clinical trials conducted on most diabetic complications. This inconsistency hinders the establishment of standardized PBM parameters, particularly concerning the optimal application setting.

Artificial Light at Night (ALAN) threatens to disrupt most natural habitats and species, including those in coastal settings, where a growing number of studies have identified ALAN impacts. A careful examination of the light properties behind those impacts is important to better understand and manage the effects of this stressor. This study focused on ALAN monochromatic wavelengths and examined which types of light spectra altered the natural activity of two prominent coastal species from the Pacific southeast: the talitroid amphipod Orchestoidea tuberculata and the oniscoid isopod Tylos spinulosus. We compared the natural daylight/night activity of these organisms with the one they exhibit when exposed to five different ALAN wavelengths: lights in the violet, blue, green, amber, and red spectra. Our working hypothesis was that ALAN alters these species' activity at night, but the magnitude of such impact differs depending on light wavelengths. Measurements of activity over 24 h cycles for five consecutive days and in three separate experiments confirmed a natural circadian activity pattern in both species, with strong activity at night (∼90% of probability) and barely any activity during daylight. However, when exposed to ALAN, activity declined significantly in both species under all light wavelengths. Interestingly, amphipods exhibited moderate activity (∼40% of probability) when exposed to red lights at night, whereas isopods shifted some of their activity to daylight hours in two of the experiments when exposed to blue or amber lights, suggesting a possible alteration in this species circadian rhythm. Altogether, our results were consistent with our working hypothesis, and suggest that ALAN reduces night activity, and some wavelengths have differential effects on each species. Differences between amphipods and isopods are likely related to their distinct adaptations to natural low-light habitat conditions, and therefore distinct sensitivity to ALAN., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The ability to analyze blunt-force trauma is crucial for deciphering valuable clues concerning mechanisms of injury and as evidence for medico-legal investigations. The use of alternate light sources (ALS) has been studied over the past decade, and is proposed to outperform conventional white light (CWL) during bruise assessments. In response to the growing interest of the technology worldwide, a systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to address the ability of ALS to detect and visualize bruising. From an initial 4055 records identified, ten studies met the eligibly criteria and were selected for this review. Evaluation also included a novel framework, referred to as SPICOT, to further systematically assess both scientific evidence and risk of bias in forensic literature. Analysis reveals that narrowband wavelengths within in the infrared or ultraviolet spectral ranges do not significantly outperform CWL in visualizing or detecting bruising. However, wavelengths within the visible spectrum, particularly 415 nm combined with longpass or bandpass yellow filters, are more effective. However, the majority of selected studies only address the sensitivity of ALS, and therefore, results may only be considered valid when the location of a bruise is known. Further investigation is required to understand the specificity of ALS, in particular how the use of topical cosmetic products, previous wounds/scar-tissue, tattoos, moles and freckles may affect detection. The ethical concern regarding the interpretation of enhanced visualized trauma should also be considered in prospect discussions prior to implementing ALS into routine practice. Nevertheless, this review finds that narrowband ALS within the visible spectrum demonstrates potential for improved injury documentation, outperforming CWL in the detection and visualization of bruising., (© 2024. The Author(s).)

Light is one of the main signals detected by plants that influence plant growth, development, and function. The light features that influence plants are the photoperiod, light intensity, and spectral composition. Manipulating light intensity and spectrum to obtain better plant growth and quality has become a popular research object in recent years. Here we describe the usage of the spectrometer Lighting Passport Pro to determine the impact of light intensity and share of individual waves in its spectrum in environment-controlled plant production systems on the growth, development, and soluble carbohydrate and phenolic synthesis of common buckwheat., (© 2024. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

Reflectance hyperspectroscopy is recognised for its potential to elucidate biochemical changes, thereby enhancing the understanding of plant biochemistry. This study used the UV-VIS-NIR-SWIR spectral range to identify the different biochemical constituents in Hibiscus and Geranium plants. Hyperspectral vegetation indices (HVIs), principal component analysis (PCA), and correlation matrices provided in-depth insights into spectral differences. Through the application of advanced algorithms-such as PLS, VIP, i PLS-VIP, GA, RF, and CARS-the most responsive wavelengths were discerned. PLSR models consistently achieved R 2 values above 0.75, presenting noteworthy predictions of 0.86 for DPPH and 0.89 for lignin. The red-edge and SWIR bands displayed strong associations with pivotal plant pigments and structural molecules, thus expanding the perspectives on leaf spectral dynamics. These findings highlight the efficacy of spectroscopy coupled with multivariate analysis in evaluating the management of biochemical compounds. A technique was introduced to measure the photosynthetic pigments and structural compounds via hyperspectroscopy across UV-VIS-NIR-SWIR, underpinned by rapid multivariate PLSR. Collectively, our results underscore the burgeoning potential of hyperspectroscopy in precision agriculture. This indicates a promising paradigm shift in plant phenotyping and biochemical evaluation.

Tectona grandis Linn., also known as teak, is a highly valued species with adaptability to a wide range of climatic conditions and high tolerance to soil variations, making it an attractive option for both commercial and conservation purposes. In this sense, the classification of cultivated teak genotypes is crucial for both breeding programs and conservation efforts. This study examined the relationship between traits related to damage in the stem of teak plants caused by Ceratocystis fimbriata (a soil-borne pathogen that negatively impacts the productivity of teak plantations) and the spectral reflectance of 110 diverse clones, using near-infrared spectroscopy (NIRS) data and partial least squares regression (PLSR) analysis. Cross-validation models had R 2 = 0.894 (ratio of standard error of prediction to standard deviation: RPD = 3.1), R 2 = 0.883 (RPD = 2.7), and R 2 = 0.893 (RPD = 2.8) for predicting stem lesion area, lesion length, and severity of infection, respectively. Teak genotypes (clones) can benefit from the creation of a calibration model utilizing NIRS-generated data paired with PLSR, which can effectively screen the magnitude of damage caused by the fungus. Overall, while the study provides valuable information for teak breeding and conservation efforts, a long-term perspective would be essential to evaluate the sustainability of teak genotypes over various growth stages and under continuous pathogen pressure.

Hyperspectral technology offers significant potential for non-invasive monitoring and prediction of morphological parameters in plants. In this study, UV-VIS-NIR-SWIR reflectance hyperspectral data were collected from Nicotiana tabacum L. plants using a spectroradiometer. These plants were grown under different light and gibberellic acid (GA 3 ) concentrations. Through spectroscopy and multivariate analyses, key growth parameters, such as height, leaf area, energy yield, and biomass, were effectively evaluated based on the interaction of light with leaf structures. The shortwave infrared (SWIR) bands, specifically SWIR1 and SWIR2, showed the strongest correlations with these growth parameters. When classifying tobacco plants grown under different GA 3 concentrations in greenhouses, artificial intelligence (AI) and machine learning (ML) algorithms were employed, achieving an average accuracy of over 99.1% using neural network (NN) and gradient boosting (GB) algorithms. Among the 34 tested vegetation indices, the photochemical reflectance index (PRI) demonstrated the strongest correlations with all evaluated plant phenotypes. Partial least squares regression (PLSR) models effectively predicted morphological attributes, with R 2 CV values exceeding 2.09 for all parameters. Based on Pearson's coefficient XYZ interpolations and HVI algorithms, the NIR-SWIR band combination proved the most effective for predicting height and leaf area, while VIS-NIR was optimal for optimal energy yield, and VIS-VIS was best for predicting biomass. To further corroborate these findings, the SWIR bands for certain morphological characteristic wavelengths selected with P values exceeding 2.09 for all parameters. Based on Pearson's coefficient XYZ interpolations and HVI algorithms, the NIR-SWIR band combination proved the most effective for predicting height and leaf area, while VIS-NIR was optimal for optimal energy yield, and VIS-VIS was best for predicting biomass. To further corroborate these findings, the SWIR bands for certain morphological characteristic wavelengths selected with s -PLS were most significant for SWIR1 and SWIR2, while i -PLS showed a more uniform distribution in VIS-NIR-SWIR bands. Therefore, SWIR hyperspectral bands provide valuable insights into developing alternative bands for remote sensing measurements to estimate plant morphological parameters. These findings underscore the potential of remote sensing technology for rapid, accurate, and non-invasive monitoring within stationary high-throughput phenotyping systems in greenhouses. These insights align with advancements in digital and precision technology, indicating a promising future for research and innovation in this field.

Background: Rotator cuff tendinopathy is a common diagnosis among patients with shoulder pain and dysfunction. Laser therapy is recommended for the treatment of this tendon disease due to the possibility of increasing tissue biostimulation. The aim of this study was to investigate the effects of HELT (high-energy laser therapy) in relation to the wavelengths of 650 nm, 810 nm, 980 nm, and 1064 nm administered., Methods: The study design was prospective and observational. Thirty patients with shoulder tendinopathy were recruited and treated in one of two high-energy laser therapy groups (5 Watt/cm 2 , 450 Joule, super-pulsed mode). Group A received a high-energy laser therapy protocol with a single wavelength (1064 nm); group B received a high-energy laser therapy program with four wavelengths (650 nm, 810 nm, 980 nm, and 1064 nm). Pain (VAS), function (ASES), and disability (DASH) were monitored at the time of recruitment (T0), 1 month later (T1), and 6 months later (T2). Roles and Maudsley scores were also evaluated at T1 and T2., Results: Both protocols resulted in improvement of pain and in functional and disability recovery at the two times of assessment, without statistically significant differences. In group B, treated with the four wavelengths, a trend emerged, bordering on statistical significance, for a greater reduction in pain., Conclusions: The high-energy laser proved to be an effective therapy for the treatment of rotator cuff tendinopathy. The possibility of modulating the choice of wavelengths could allow the customization of the protocol in relation to the patient's clinical condition.

In this study, we investigated the use of artificial intelligence algorithms (AIAs) in combination with VIS-NIR-SWIR hyperspectroscopy for the classification of eleven lettuce plant varieties. For this purpose, a spectroradiometer was utilized to collect hyperspectral data in the VIS-NIR-SWIR range, and 17 AIAs were applied to classify lettuce plants. The results showed that the highest accuracy and precision were achieved using the full hyperspectral curves or the specific spectral ranges of 400-700 nm, 700-1300 nm, and 1300-2400 nm. Four models, AdB, CN2, G-Boo, and NN, demonstrated exceptional R 2 and ROC values, exceeding 0.99, when compared between all models and confirming the hypothesis and highlighting the potential of AIAs and hyperspectral fingerprints for efficient, precise classification and pigment phenotyping in agriculture. The findings of this study have important implications for the development of efficient methods for phenotyping and classification in agriculture and the potential of AIAs in combination with hyperspectral technology. To advance our understanding of the capabilities of hyperspectroscopy and AIs in precision agriculture and contribute to the development of more effective and sustainable agriculture practices, further research is needed to explore the full potential of these technologies in different crop species and environments.

Simultaneous removal of chlorite (ClO 2 - ) and organic micro-pollutants (OMPs) by the irradiation of UV is a novel process. In this study we used UV light emitting diode (UV-LED) as a new UV source to systematically investigate the effect of UV wavelength (255, 285, 365 nm) on the simultaneous removal of carbamazepine (CBZ) and ClO 2 - . Removal of both CBZ and ClO 2 - followed the order of 255, 285, and 365 nm. Formation of hydroxyl radical and reactive chlorine species (RCS) were confirmed during the photolysis of ClO 2 - using probe compounds. RCS were always the predominant contributor to the degradation of CBZ in UV-LED/ClO 2 - system. The impacts of ClO 2 - dosage, pH, bicarbonate/carbonate (HCO 3 - /CO 3 2- ), and the effect of natural organic matter (NOM) on CBZ degradation were also evaluated. This study identified the products produced by CBZ through possible degradation pathways during the transformation process. Further, the amount of ClO 2 - may affect the amount of chlorate produced in UV/ClO 2 - system. Overall, our research provides an in-depth analysis of the effects of UV wavelength on the simultaneous removal of ClO 2 - and OMPs in water., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Non-destructive estimation of the internal properties of fruits and vegetables is very important, because better management can be provided for subsequent operations. Researchers and scientists around the world are focusing on non-destructive methods because if they are developed and commercialized, there will be an impressive change in the food industry. In this regard, this paper aims to present a non-destructive method based on Vis-NIR spectral data. The different stages of the proposed algorithm are: (1) Collection of samples of Gala apples, (2) Spectral data extraction by spectroscopy, (3) Pre-processing of spectral data, (4) Measurement of chemical properties of titratable acidity (TA) and taste index, (5) Selection of key wavelengths using hybrid artificial neural network-firefly algorithm (ANN-FA), (6) Non-destructive estimation of the properties using two methods of hybrid ANN- Particle swarm optimization algorithm and partial least squares regression. For considering the reliability of methods for estimating the chemical properties, the prediction operation was executed in 300 iterations. The results represented that the mean and standard deviation of the correlation coefficient and the root mean square error of hybrid ANN-PSO and PLSR for TA were 0.9095 ± 0.0175, 0.0598 ± 0.0064, 0.834 ± 0.0313 and 0.0761 ± 0.0061 respectively. These values for taste index were 0.918 ± 0.02, 3.2 ± 0.39, 0.836 ± 0.033 and 4.09 ± 0.403, respectively. Therefore, it can be concluded that the hybrid ANN-PSO has a better performance for non-destructive prediction of the two mentioned chemical properties than the PLSR method. In general, the proposed method can predict the chemical properties of TA and taste index non-destructively, which is very useful for mechanized harvesting and management of post-harvest operation.

The aim of the study is to test the application of different laser wavelengths, with and without different photosensitizing dyes on different types of cultures. Laser irradiation was realized on Streptococcus mutans in both solid and liquid culture media in continuous mode at three different fluences (10, 20, and 30 J/cm 2 ) with a red diode (650 nm) with toluidine blue dye, a blue-violet diode (405 nm) with curcumin dye, and a green diode (532 nm) with erythrosine dye. Without a photosensitizer, no growth inhibition was obtained with the red diode at any fluence value. Inhibition rates of 40.7% and 40.2% were obtained with the blue diode and green diode. The blue diode laser used with curcumin obtained results in terms of growth inhibition up to 99.26% at a fluence of 30 J/cm 2 . The red diode laser used with toluidine blue obtained results in terms of growth inhibition up to 100% at fluences of 20 and 30 J/cm 2 . The KTP (potassium-titanyl-phosphate) laser used with erythrosine was able to determine a complete growth inhibition (100%) at the different fluence values. The combination of a laser and its proper color may dramatically change the results in terms of bactericidal effect. It will be interesting to confirm these data by further in vivo studies.

Objectives: To assess the impact of irradiation on Martens hardness parameters of different PEEK qualities filled with titanium dioxide (TiO 2 ), namely PEEK/0%, PEEK/20%, and PEEK/>30%., Methods: For Martens hardness (HM) measurements, 40 specimens of each PEEK quality were fabricated and air-abraded with 50μm Al 2 O 3 . HM parameters of PEEK specimens were measured initially and stepwise after irradiating for 5, 10, 20, 30, 40, 60, 80, 100, 180, 360 and 540s using light units with different wavelength: Elipar S10 (430-480nm), EyeVolutionMAX (385-390nm+465-470nm), Translux CL (380-500nm) and bre.Lux Power Unit (370-500nm). HM parameters of 10 human teeth were measured initially on enamel and dentin. Data was analysed using 3-way ANOVA with partial eta-squared (η P 2 ) and post-hoc Tuckey-HSD-test (p<0.05)., Results: PEEK qualities followed by the wavelength showed the highest effect on Martens hardness (p<0.013). PEEK/>30% (197.35±19.9N/mm 2 ), followed by PEEK/20% (191.45±15.49 N/mm 2 ) showed significantly higher values for HM than PEEK/0% (189.55±16.89N/mm 2 ). PEEK/>30% (5.49±0.4kN/mm) and PEEK/20% (5.38±0.26kN/mm 2 ) presented higher indentation modulus (E IT ) than PEEK/0% (4.77±0.36kN/mm 2 ). Irradiated with wavelength of 430-480nm (PEEK/0%: 193.28N/mm 2 , PEEK20%: 198.83N/mm 2 , PEEK/>30%: 200.5N/mm 2 ) indicated higher HM compared to specimens irradiated with 380-500nm (PEEK/0%: 186.63N/mm 2 , PEEK20%: 191.05N/mm 2 , PEEK/>30%: 196.13N/mm 2 ). Irradiation using 430-480nm (PEEK/0%: 4.95kN/mm 2 , PEEK20%: 5.52kN/mm 2 , PEEK/>30%: 5.59kN/mm 2 ) and 370-500nm (PEEK/0%: 4.92kN/mm 2 , PEEK20%: 5.43kN/mm 2 , PEEK/>30%: 5.53kN/mm 2 ) indicated higher E IT values compared to specimens irradiated with 380-500nm (PEEK/0%: 4.72kN/mm 2 , PEEK20%: 5.34kN/mm 2 , PEEK/>30%: 5.47kN/mm 2 ). Duration of irradiation presented no impact on results. Enamel (HM: 2263.6±405.16, E IT : 63.16±19.24) and dentin (HM: 468.2±30.77N/mm 2 , E IT : 14.14±4.59kN/mm 2 ) presented significantly higher HM and E IT than the tested PEEK qualities (p<0.001)., Significance: Irradiation with different wavelength impacted HM parameter. The increase of TiO 2 percentage in PEEK matrix improved the HM parameter. However, PEEK showed significantly lower HM parameter than human teeth., (Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Exposure of the chick embryo to different wavelengths of light of the same intensity has shown that only certain wavelengths may be important in generating visual asymmetries. This study aimed to detect the possible influence of different wavelengths of light on development of asymmetry of social recognition in zebrafish larvae, tested using the fish's mirror image as the stimulus. From fertilization until day 10 post-hatching zebrafish were kept in five different lighting conditions: natural light/dark (LD) cycle, complete darkness (DD), and artificial LD cycles with 14 h of monochromatic light (red, green, or violet light) and 10 h of darkness (rLD 14:10, gLD 14:10, vLD 14:10, respectively). On day 10 after hatching, the zebrafish larvae were subjected to a mirror test. A preference for using the left eye to scrutinize their mirror image was apparent only in zebrafish larvae exposed to and reared under a natural LD cycle, and not following exposure to any of other lighting conditions. These results are discussed with reference to other evidence of brain lateralization., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The quality and regulation of the incident light is crucial in microalgae cultivation processes. Depending on wavelength, spectrum, and intensity, growth characteristics and biochemical composition of these organisms vary. With mainly fluorescent lamps (FL) used previously for illumination, such variabilities could not be studied adequately due to their broad emission spectrum. In contrast, light-emitting diodes (LEDs) emit a very narrow wavelength band and enable flexible photobioreactor designs due to their small size. This review provides a condensed overview on the application of LEDs in microalgal cultivation processes. It summarizes the current availability and applicability of LED technologies as an illumination source for research-focused photobioreactor systems. A particular focus is the use of narrow-wavelength LEDs to address fundamental as well as applied aspects of light color on algae biomass and value-added compound formation. In this respect, the application of internal and external illumination systems is reviewed together with trends in the industrial use of LED systems to intensify algae process efficiency.

In this article, the authors review basic fundamental principles of light characteristics and their interaction with the target tissue. It is imperative for the practitioner to understand these concepts to deliver appropriate, efficacious, and safe phototherapeutic treatment for their patients. Once a diagnosis is made and a laser is chosen as a treatment tool, a basic knowledge and understanding of the physics and properties of light/tissue interaction is essential to allow practitioners to provide their patients with optimal results.

All available experimental measurements of the spectrum of the Ag(+) ion are critically reviewed. Systematic shifts are removed from the measured wavelengths. The compiled list of critically evaluated wavelengths is used to derive a comprehensive list of energy levels with well-defined uncertainties. Eigenvector compositions and level designations are found in two alternate coupling schemes. Some of the older work is found to be incorrect. A revised value of the ionization energy, 173283(7) cm(-1), equivalent to 21.4844(8) eV, is derived from the new energy levels. A set of critically evaluated transition probabilities is given.

Recent observations at the National Institute of Standards and Technology indicate that the Ar I wavenumbers reported by Whaling et al. [J. Res. Natl. Inst. Stand. Technol. 107, 149 (2002)] are systematically too large. To investigate the source of this problem, selected lines of Ar I and Ar II were remeasured in the same spectra used by Whaling et al. The measurements show that the Ar I wavenumbers of Whaling et al. are systematically shifted with respect to the Ar II wavenumbers previously reported by Whaling et al. [J. Quant. Spectrosc. Radiat. Transfer 53, 1 (1995)] based on the same spectra. The Ar I wavenumbers can be corrected by a constant multiplicative correction of 0.999 999 933.

We have observed the spectrum of neutral neon (Ne I) emitted by a microwave-excited electrodeless discharge lamp with the National Institute of Standards and Technology 2 m Fourier transform spectrometer. The spectra cover the regions 6929 Å to 11 000 Å with a resolution of 0.01 cm(-1) and 11 000 Å to 47 589 Å with a resolution of 0.007 cm(-1). We present a line list that includes more than 650 classified lines and provides an accurate and comprehensive description of the infrared spectrum. The response of the Fourier transform spectrometer was determined by using a radiometrically calibrated tungsten strip lamp, providing relative intensities that for moderate to strong lines are accurate to approximately 10 % over the entire range of the observations. The identities of many lines that were previously multiply classified are unambiguously resolved.

We report precision measurements by Fourier transform spectroscopy of the vacuum wavenumber, line width, and relative signal strength of 928 lines in the Ar I spectrum. Wavelength in air and classification of the transition are supplied for each line. A comparison of our results with other precision measurements illustrates the sensitivity of Ar I wavelengths to conditions in the light source.

New measurements of Ar III wavelengths between 508 Å and 4183 Å are combined with measurements from the literature to find improved values for the energy of most of the known levels in Ar III. Parameters derived from fitting the new level energies to an LS -coupling model are presented along with eigenvector compositions of the levels. On the basis of this analysis new designations are recommended for several levels.

Interferometrically-measured wavelengths of 109 lines of neutral Kr 84 are compared with those of Kr 86 . Sixty energy levels of neutral Kr 84 derived from those wavelengths and 25 Kr 86 -Kr 84 isotope shifts previously measured are given along with their shifts from the energy levels of Kr 86 . Twenty levels of each of Kr 82 , Kr 80 , and Kr 78 are also evaluated using isotope-shift information in the literature. The differences between the experimentally observed shifts and the normal mass shift leave large negative residuals which are accounted for by ionization energy differences and by the specific mass shift. It appears that the volume effect causes only a very small, if any, energy level shift.

The spectrum of doubly ionized molybdenum (Mo III) was produced in a sliding spark discharge and recorded photographically on the NIST 10.7-m normal incidence spectrograph in the 800-3250 Å spectral region. The analysis has led to the establishment of 76 levels of the interacting 4 d 4 , 4 d 3 5 s and 4 d 2 5 s 2 even configurations, 73 levels of the interacting 4 d 3 5 d and 4 d 3 6 s even configurations, and 181 levels of the interacting 4 d 3 5 p and 4 d 2 5 s 5 p odd configurations. Approximately 3100 lines have been classified as transitions between these experimentally determined levels. Comparison between the observed levels and those calculated from matrix diagonalizations with least-squares fitted parameters shows standard deviations of 44, 33, and 183 cm -1 , respectively, for the levels of the three sets of configurations.

An analysis of Cu iii based on observations from 500 to 6900 Å is presented. The low structures 3 d 9 and 3 d 8 4 s are complete, including the rarely, if ever before, found 3 d 8 ( 1 S)4 s 2 S. The 3 d 7 4 s 2 includes 4 F, 2 F, 2 G, and 2 H but the 4 P, 2 P, a 2 D, b 2 D have eluded all attempts to find them. The ionization potential calculated from 4 s , 5 s , 6 s 4 4 F 4 1 / 2 is 296 980 cm -1 but by a comparison with Ni II which has a longer series an approximate value of 297 140 can be estimated. The 3 d 8 4 d group is complete, except for one level, as is 5 d based on 3 F and 1 G, the other 5 d groups being incomplete. 3 d 8 ( 3 F)4 f is complete and 26 levels based on 1 D, 3 P, 1 G are known. 3 d 8 ( 3 F)5 g is incomplete and a few levels based on 1 D and 1 G have been found. A discussion of the validity of the analysis of Cu iv by J. F. Schröder and Th. A. M. Van Kleef is given.

A list of about 9500 classified lines of Th I in the range 2345-29 662 Å is given. Lines in the range 2345-9239 A were observed and measured at NBS. Zeeman effect data for 2281 lines are listed. Lists of 254 even and 322 odd levels including their g values are presented. Among them there are 72 new levels, which were not contained in earlier publications.

The spectrum of doubly ionized tungsten (W III) was produced in a sliding-spark discharge and recorded photographically on the NIST 10.7-m normal-incidence vacuum spectrograph in the 600-2680 Å spectral region. The analysis has led to the establishment of 71 levels of the interacting 5 d 4 , 5 d 3 6 s and 5 d 2 6 s 2 even configurations and 164 levels of the interacting 5 d 3 6 p and 5 d 2 6 s 6 p odd ones. A total of 2636 lines have been classified as transitions between the 235 experimentally determined levels. Comparison between the observed levels and those calculated from matrix diagonalizations with least-squares fitted parameters shows an rms deviation of ±87 cm -1 for the even configurations and ±450 cm -1 for the odd ones.

A new set of measurements of the spectrum of neutral thulium covering the range of 2513 Å to 11750 Å is given. The light source utilized for the observations was a microwave-excited thuliumiodide lamp. Second spectrum lines were recognized by comparing the output of this lamp with that of a 6A sliding spark. The results of Zeeman effect studies of these lines are included. Analysis of these new data led to the discovery of 348 new energy levels and provided revised values for the 142 already published. Measured Landé g factors are given for most of the levels.

Measurements of the spectrum of doubly ionized praseodymium from 821 to 2103 Å are given. One hundred fifty-three energy levels deduced from these wavelengths and an earlier line-list of longer wavelengths are presented. These levels are identified with the configurations 4f 2 6s, 4f 2 7s, 4f 2 8s, 4f 2 6p, 4f 2 6d, 4f 2 5f, 5d 2 4f, and 4f5d6s and are given term designations. Radial energy integrals belonging to these configurations are parametrically deduced from the known levels. A value of 21.625 eV (174420 cm -1 ) for the ionization energy of Pr iii, with an estimated uncertainty of 0.016 eV (130 cm -1 ), is derived from the 4f 2 ns series (n = 6, 7, 8).

The cerium spectrum emitted by an electrodeless lamp has been observed with a SISAM spectrometer in the region from 0.82 to 2.42 μ m. Of the 2076 lines observed, about 1100 lines have been classified as transitions in the energy level system of Ce I and 400 lines in Ce II. The average deviation between the observed wave numbers and those calculated from the two energy levels is ±0.023 cm -1 .

The first spectrum of tungsten (W i) has been observed in the region between 2000 Å and 10500 Å. Of the 6800 spectral lines reported here, about 5500 have been classified as transitions between 91 even and 365 odd levels.

The second spectrum of cerium (Ce ii) has been compiled in the wavelength region between 2500 Å and 24 000 Å. Of the 11 000 lines in the list, about 7500 are now classified as transitions between 192 odd levels and 288 even levels. The odd levels arise from 5 configurations (4 f 5 d 2 , 4 f 5 d 6 s , 4 f 6 s 2 , 4 f 2 6 p , and 4 f 3 ) and the even levels from 7 configurations (4 f 2 6 s , 4 f 2 5 d , 4 f 5 d 6 p , 4 f 6 s 6 p , 5 d 3 , 5 d 2 6 s , and 5 d 6 s 2 ). The known levels extend up to only 52 000 cm -1 although the ionization potential is known to be 35 000 cm -1 higher.