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Two new surfactant sensors were developed by synthesizing Pt-doped acid-activated multi-walled carbon nanotubes (Pt@MWCNTs). Two different ionophores using Pt@MWCNTs, a new plasticizer, and (a) cationic surfactant 1,3-dihexadecyl-1H-benzo[d]imidazol-3-ium-DHBI (Pt@MWCNT-DHBI ionophore) and (b) anionic surfactant dodecylbenzenesulfonate-DBS (Pt@MWCNT-DBS ionophore) composites were successfully synthesized and characterized. Both surfactant sensors showed a response to anionic surfactants (dodecylsulfate (SDS) and DBS) and cationic surfactants (cetylpyridinium chloride (CPC) and hexadecyltrimethylammonium bromide (CTAB)). The Pt@MWCNT-DBS sensor showed lower sensitivity than expected with the sub-Nernstian response of ≈23 mV/decade of activity for CPC and CTAB and ≈33 mV/decade of activity for SDS and DBS. The Pt@MWCNT-DHBI surfactant sensor had superior response properties, including a Nernstian response to SDS (59.1 mV/decade) and a near-Nernstian response to DBS (57.5 mV/decade), with linear response regions for both anionic surfactants down to ≈2 × 10 -6 M. The Pt@MWCNT-DHBI was also useful in critical micellar concentration (CMC) detection. Common anions showed very low interferences with the sensor. The sensor was successfully employed for the potentiometric titration of a technical grade cationic surfactant with good recoveries. The content of cationic surfactants was measured in six samples of complex commercial detergents. The Pt@MWCNT-DHBI surfactant sensor showed good agreement with the ISE surfactant sensor and classical two-phase titration and could be used as an analytical tool in quality control.

A laser absorption spectroscopy diagnostic integrated within a hardened optical probe was used to measure temperature and water mole fraction at 500 kHz in post-detonation fireballs of explosives. In the experiments, an exploding-bridgewire detonator initiated a 25 g hemisphere of explosive (N5 or PETN). This produced a hemispherical fireball that traveled radially towards a hardened measurement probe. The probe contained a pressure transducer and optical equipment to pitch fiber-coupled laser light across a 12.6 cm gap onto a detector. Tunable diode lasers emitting near 7185.6 and 6806 c m -1 were used to measure the absorbance spectrum of H 2 O utilizing peak-picking scanned-wavelength-modulation spectroscopy with a scan frequency of 500 kHz and modulation frequencies of 35 and 45.5 MHz, respectively. This enabled measurements of temperature and X H 2 O in the shock-heated air and trailing fireball at 500 kHz. Time histories of pressure, temperature, and H 2 O mole fraction were acquired at different standoff distances to quantify how the fireball evolved in space and time as well as to compare measured quantities between PETN and N5 fireballs. The standard deviation of temperature and X H 2 O during one representative test were found to be 17 K (1.3%) and 0.011 (5%), respectively. These measurements demonstrate this diagnostic's ability to provide rapid and reliable measurements in harsh, highly transient post-detonation environments produced by solid explosives.

Detailed spectroscopic measurements of high explosive detonation breakout in the ultraviolet region are presented. Molecular features associated with CN, NH, OH, and N 2 are observed and analyzed. Spectra indicate extreme temperatures well in excess of 5000 K in the first few microseconds after breakout. Molecular bands are found to originate from the detonation products, as opposed to the ambient air, and are strongly attenuated in the presence of oxygen. Implications for forensic analysis of source explosive are discussed.

Spectroscopic signatures of cased high-explosive charge denotations are examined using emission spectroscopy with sub nanometer resolution. Eleven distinct case materials are investigated for atomic features of their major alloying elements. Molecular features of case material combustion products are also investigated for five case materials. Emission is monitored within the 275-425 nm range for atomic features and in the 310-755 nm range for molecular features. Major alloying elements with concentrations greater than 5% are generally detected through atomic emission. Al, Cu, Fe, Mg, Cr, Mn, Pb, and Ni are all detected in concentrations less than 5%. Undetected elements include Zn, Nb, Ta, and V. Molecular emission from aluminum monoxide, titanium monoxide, and CN is measured for aluminum alloy, titanium alloy, and carbon fiber cases, respectively.

Purpose: Electrochemotherapy is increasingly entering into national and international guidelines, requiring formal evaluation of treatment costs and cost-effectiveness to ensure that its uptake provides value to budget-constrained health care systems. This study analyzed the early cost-effectiveness of electrochemotherapy in patients with Stage IIIc/IV skin melanoma in clinical practice in Slovenia. The costs of electrochemotherapy were compared to those of the standard of care, consisting of palliative treatment and therapy for symptoms., Methods: wThe study enrolled 23 patients treated with electrochemotherapy at the Institute of Oncology (Ljubljana, Slovenia). The mean cost of electrochemotherapy was estimated using patient-specific cost data on electrochemotherapy procedures and subsequent follow-up. Quality-adjusted life-years (QALYs) were estimated by collecting EQ-5D-3L questionnaires at baseline, after complete or partial response following the treatment, and after a relapse of skin lesions. A discrete-time Markov model was built to estimate the lifetime costs and consequences of using electrochemotherapy compared to standard of care, from the perspective of the Slovenian health care system. The analysis was conducted separately in the whole patient sample and in the subset of patients with bleeding lesions. Deterministic and probabilistic sensitivity analyses were conducted to test model assumptions and to characterize the uncertainty around model parameters., Findings: In the whole patient population, electrochemotherapy for skin melanoma Stage IIIc/IV was expected to increase QALYs by 0.29 (95% credible interval [CrI], 0.10-0.50), at the higher cost of 6568 EUR (95% CrI, 4593-8928) in comparison to the standard of care. At the cost-effectiveness threshold of 20,000 EUR/QALY, the estimated probabilities of electrochemotherapy being cost-effective compared to standard of care were 0.30 and 0.91 in the whole patient sample and in patients with bleeding lesions, respectively. In the whole sample population, a 50% reduction in the price of the electrodes was expected to increase the probability of electrochemotherapy being cost-effective from 0.30 to ~0.64., Implications: The findings from this cost-effectiveness analysis of data from clinical practice were based on a small sample size (ie, 23 patents), which made the subgroup of patients with bleeding lesions very small. Therefore, the findings in this patient population should be carefully interpreted., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Climate change and the increased demand for food amplified the global problem with water supply for irrigation. This work deals with the reclamation of municipal wastewater (MWW) for irrigation by a membrane bioreactor (MBR), nanofiltration (NF), and reverse osmosis (RO). The emphasis was on the comparison of physico-chemical and microbiological parameters with the World Health Organization (WHO) and the European Union (EU) guidelines. In addition, the detection and removal of contaminants of emerging concern (CEC) from the Watch List (EU Decision 2015/495) were examined. Firstly, the MWW was monitored (physico-chemical and microbiological parameters, trace elements, and occurrence of CECs) for six months. Thereafter, the MWW was treated with MBR, NF, and RO. The reclaimed water satisfied the physico-chemical and microbiological quality requirements only after additional NF/RO treatment. Membrane bioreactor efficiently removed methiocarb (>99.9%), tri-allate (>99.9%), clothianidin (88.0%), and clarithromycin (71.9-74.2%), while the removal of azithromycin, acetamiprid, and oxadiazon was around 30%. The low and even negative removal during MBR treatment was observed for diclofenac (15%), clothianidin (-14%), imidacloprid (-18%), and diclofenac (-157%). Additional treatment of MBR effluent with NF90 and XLE membranes resulted in complete rejection of detected CECs, while NF270 membrane achieved results between 75% and 91%., 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 © 2020 Elsevier B.V. All rights reserved.)

Uranium, because of its pyrophoricity, oxidizes rapidly in an oxygen-containing high-temperature environment. However, so far, the identification of uranium oxide (UO) emission from a laser-produced plasma system is limited to a spectral feature around 593.55 nm. The aim of this study is to elucidate UO emission features in the visible spectral regime from uranium plasmas generated in an environment with varying oxygen concentrations. The plasmas are produced by focusing nanosecond laser pulses on a uranium metal target in a controlled ambient environment. Space- and time-resolved optical emission spectroscopic investigations are used for isolating UO molecular emission structures from crowded U atomic line emission. Our studies highlight that the emission from a U plasma, even in the presence of trace oxygen is accompanied by a strong background-like emission with partially resolved bands from uranium monoxide and higher oxides. We also report several UO spectral emission bands in the visible spectral region.

A dual framing camera system was coupled with custom-designed ultrafast imaging spectrometer optics to yield simultaneous imaging and imaging spectroscopy of extremely short detonation interaction events in reactive materials. For short exposures of 100 ns or less, spectral resolutions of 2.4 Å are achievable, allowing for time-resolved identification of key intermediate species evolving from prompt reaction. Under some circumstances, emission can be fit to a local emission temperature, assuming the optically thin limit. Applications to reactive metal systems involving aluminum, magnesium, titanium, boron, and silicon are demonstrated.

Broadband frequency doubling of a modeless dye laser pulse is used to enable single-shot absorption spectroscopy in the ultraviolet for optically dense, energetic-materials fireball applications. Band widths of approximately 1-3 nm are generated in the 226 and 268 nm regions using a doubling crystal. Strong focusing of the fundamental beam onto the crystal is found to be sufficient to achieve 1-5% conversion efficiency with a pulse intensity sufficient to saturate the array detector even after 75% attenuation through the fireball. The technique is demonstrated with nitric oxide (NO) absorption in a gas cell and is then used to perform the first detection and temperature fitting of aluminum monofluoride (AlF) and magnesium monofluoride (MgF) in a fireball environment.

Background: The aim of the study was to determine whether the presence of inguinal sentinel lymph node (SLN) metastases smaller than 2 mm (micrometastases) subdivided according to the number of micrometastases predicts additional, non-sentinel inguinal, iliac or obturator lymph node involvement in completion lymph node dissection (CLND). PATIENTS AND METHODS.: Positive inguinal SLN was detected in 58 patients (32 female, 26 male, median age 55 years) from 743 consecutive and prospectively enrolled patients with primary cutaneous melanoma stage I and II who were treated with SLN biopsy between 2001 and 2007., Results: Micrometastases in inguinal SLN were detected in 32 patients, 14 were single, 2 were double, and 16 were multiple. Twenty-six patients had macrometastases., Conclusions: No patient with any micrometastases or a single SLN macrometastasis in the inguinal region had any iliac/obturator non-sentinel metastases after CLND in our series. Furthermore, no patient with single SLN micrometastasis in the inguinal region had any non-sentinel metastases at all after CLND in our series. In these cases respective CLND might be omitted.

A modeless broadband dye laser is applied to probe inside optically dense fireballs generated by high explosives using single-shot, high resolution absorption spectroscopy. Despite attenuation of the main beam by 98%, high signal-to-noise ratio absorption spectra of Al, Ti, and AlO are readily obtained at resolutions of 0.007 nm, and luminosity from the fireball is strongly rejected. Detection limits for atomic species are less than 200 ppb. The method offers good time resolution of chemistry within the fireball, and scaling laws suggest that this technique should be valid in explosives tests at least up to the gram scale.

Background and Objectives: Cutaneous melanoma patients with positive sentinel lymph node biopsy (SLNB) are being treated with completion lymph node dissection (CLND). The aim of our study was to determine the predictive value of sentinel lymph node (SLN) micrometastases (metastases less than 2 mm in diameter) in assessing further lymph node involvement in CLND., Methods: Between 2001 and 2005, we performed 476 SLNB in patients with stages I and II melanoma; 74 had metastases in SLN. We evaluated retrospectively the metastases in SLN according to their size and number. The presence of additional metastases in non-sentinel lymph nodes after CLND was evaluated., Results: Thirty-nine patients had micrometastases, 22 of them were solitary, 3 were double, and 14 patients had multiple micrometastases in SLN. Out of 22 solitary micrometastases, no patient had additional metastases in non-sentinel lymph nodes. From 3 patients with double micrometastases, 1 patient had further metastases in non-sentinel lymph nodes after CLND. Out of 14 patients with multiple micrometastases, 2 had additional metastases in CLND., Conclusions: No patient with a single SLN micrometastasis had further metastases after CLND in our series. CLND may not be beneficial after detecting a single micrometastasis in SLN.

The aim of this study was to evaluate the role of tyrosinase mRNA appearance in blood of malignant melanoma (MM) patients, especially with advanced stages, for predicting the disease progression, and consequently the survival. The tyrosinase mRNA was measured by nested RT-PCR in peripheral venous blood samples obtained from 86 patients (53 male and 33 female) with mainly stage III and IV MM. The data were analyzed using standard methods for survival analysis and logistic regression. Tyrosinase was negative in the MM patients with the disease stage I or II, positive tyrosinase was in 11/50 patients with stage III and in 5/22 patients with stage IV. Systemic metastases developed in 14/16 patients with positive tyrosinase and in 41/70 with negative tyrosinase. The 3-year survival was 8% and 28% among the patients with positive and the patients with negative tyrosinase, respectively. The log rank test showed statistically significant better survival of tyrosinase negative patients when compared to tyrosinase positive patients (p=0.039). Multivariate analysis using logistic regression indicated tyrosinase to be a statistically significant prognostic factor for the survival of MM patients after controlling for Breslow and ulceration values (p=0.006). Positive tyrosinase in peripheral venous blood is statistically significant, and more importantly independent negative predictor of survival.

Twenty-nine isolates of Malassezia pachydermatis were recovered from a single farm of 100 pigs in Croatia. In contrast, 290 farm pigs from other locations (northern parts of Croatia and Slovenia) yielded only two non-lipid dependent isolates of M. pachydermatis using the same swabbing procedure. Ten of the 29 isolates from a single farm had their identity confirmed by karyotyping, and were typed by restriction fragment length polymorphism (RFLP) analysis. All but one of these isolates sub-typed were indistinguishable, one isolate produced a slightly different RFLP profile. Control isolates recovered from dog skin gave RFLP profiles that were easily distinguished from those produced by the pig isolates. These results suggest that a single strain of M. pachydermatis had colonised this pig herd.

Malignant melanoma (MM) has a high metastatic potential even in small primary lesions, and an early distinction between localized and regionally/distally advanced disease is of major importance for the patients' treatment and, consequently, for their survival. Exploiting the fact that tyrosinase is a tissue specific enzyme which is only expressed in normal skin melanocytes and MM cells that invade the blood during metastasizing, the objective of our study was to optimise the nested RT-PCR assay for the detection of tyrosinase mRNA and, hence, to detect circulating melanoma cells (CMC) in whole venous blood of MM patients. Eighteen MM patients (stage III and IV, according to AJCC) and 8 healthy subjects were included in our study. Following optimisation of the procedure, the lowest detection limit of 10 MM cells per 1 ml of the blood was achieved. Tyrosinase mRNA was detected in 27.8% (5/18) of blood samples from MM patients and in none of the healthy volunteers. Preliminary results of this study suggest that the method is sensitive and specific to the CMC detection in the peripheral blood and may thus be helpful in determining the disease stage and, consequently, in planning treatment.