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Identifying the fibres in historical textiles presents a complex challenge due to the wide variety of plant, animal and early synthetic materials that have been used. Traditionally, this identification process involves sampling followed by either microscopic examination or ATR-FTIR spectroscopy. However, there are instances when sampling is restricted due to the good condition or significant value of the object under analysis. Additionally, the presence of leather components alongside textiles can further complicate the identification. This paper proposes a novel non-invasive method for fibre identification based on External Reflection (ER) FTIR spectroscopy, which has been rarely applied to textiles or leather. The current research demonstrates that ER-FTIR spectrum is a viable tool for fibre identification on both recent and historical textiles. The non-invasiveness of the analytical approach enables a comprehensive investigation without compromising the number or position of samples. Respect to ATR-FTIR spectra, the ER-FTIR spectra frequently exhibit an amplification of certain diagnostic bands, facilitating the identification of the various fibres examined in this study (cotton, hemp, viscose, silk, wool, leather, polyamide, acrylic, polyester). The extended spectral range (7500-375 cm -1 ) which is provided by ER-FTIR spectrometry also contains extra bands in the near infrared region, which can provide key information for the discrimination due to the lack of distortion phenomena. The technique was applied to the characterisation of textile materials coming from a collection of 10 traditional Japanese samurai armours spanning from the 16th to the 20th century (Museo delle Culture, Lugano, Switzerland). For the first time, the results provided a comprehensive overview of the textiles utilized in Japanese armours across various historical periods. Overall, the appearance of materials in samurai armours reflects the evolution of armour-making techniques and the influence of socio-cultural factors throughout Japanese history. Synthetic and semi-synthetic materials were easily detected, revealing the occurrence of a past conservation treatment or the early adoption of modern man-made materials in the manufacturing of traditional armours. The approach outlined in this case study can be applied to textile collections of various kinds, offering a reliable mean to discern the yarn composition and detect non-original components. The method also appears as a valuable prescreening tool for designing a less intrusive yet more informative sampling strategy, should additional details about fibre type and dyeing be necessary., 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 The Author(s). Published by Elsevier B.V. All rights reserved.)

Mercury is a pervasive and concerning pollutant due to its toxicity, mobility, and tendency to biomagnify in aquatic and terrestrial ecosystems. Speciation analysis is crucial to assess exposure and risks associated with mercury, as different mercury species exhibit varying properties and toxicities. This study aimed at developing a selective detection method for organic mercury species in a non-invasive biomonitoring matrix like human hair. The method is based on frontal chromatography (FC) in combination with inductively coupled plasma mass spectrometry (ICP-MS), using a low pressure, homemade, anion exchange column inserted in a standard ICP-MS introduction system, without requiring high-performance liquid chromatography (HPLC) hyphenation. In addition to the extreme simplification and cost reduction of the chromatographic equipment, the proposed protocol involves a fast, streamlined and fully integrated sample preparation process (in contrast to existing methods): the optimized procedure features a 15-min ultrasonic assisted extraction procedure and 5 min analysis time. Consequently, up to 100 samples could be analyzed daily, making the method highly productive and suitable for large-scale screening programs in public and environmental health. Moreover, the optimized procedure enables a limit of detection (LOD) of 5.5 μg/kg for a 10 mg hair microsample. All these features undeniably demonstrate a significant advancement in routine biomonitoring practices. To provide additional evidence, the method was applied to forty-nine human hair samples from individuals with varying dietary habits successfully finding a clear correlation between methylmercury levels (ranging from 0.02 to 3.2 mg/kg) in hair and fish consumption, in line with previous literature data., 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 © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

A fast and cost-effective procedure based on Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) for the selective determination of methylmercury (MeHg) is proposed and validated for fish tissue analysis. Selectivity for MeHg is achieved by simply inserting a strong anion exchange resin to block inorganic mercury as negatively charged chloride species, leaving MeHg unretained. The procedure features a 15 min extraction time followed by a 100 s analysis time achieving a limit of detection of 1.6 μg kg -1 on solid samples. The effect of the solution composition and inorganic mercury concentration were extensively studied to fully assess the selectivity of the procedure: Hg(II):MeHg ratios up to 50 are tolerated and cause systematic errors lower than 15%. The entire procedure was successfully validated by standard reference material from the marine food web, namely fish muscle and liver plus zooplankton. The method was finally applied to the detection of MeHg in the marine trophic web of Djibouti (Gulf of Aden): a trophic magnification factor of 13.5 proved the high risk associated with the biomagnification of methylmercury., 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 © 2022 Elsevier B.V. All rights reserved.)

An analytical method derived from the coupling of frontal chromatography (FC) with Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) is proposed for the fast determination of Cr(VI) ultra-traces. The insertion of a short, homemade column filled with a strong cationic exchange resin in the flow-path of a commercial ICP-MS allows on-line trapping of cationic Cr(III) and elution of anionic Cr(VI). As a result, only the Cr(VI) front reaches the detector. This separation mechanism enables the highly selective quantification of Cr(VI) ultra-traces (LOD = 0.026 µg/kg - defined as 3 s of 10 replicated measurements of a 0.050 µg/kg solution) over a wide linearity range (tested up to 1024 µg/kg), even in the presence of Cr(III) concentration as high as 50 mg/kg. Key advantages of the proposed method are the extremely short analysis time (one minute), together with the simplicity and cost-effectiveness of the modifications applied over a commercial ICP-MS instrumental configuration. No time- or chemical-consuming pretreatments are needed: it is only necessary to acidify the sample prior Cr(VI) determination, as normally performed for common ICP-MS analysis. The applicability of the method was demonstrated over mineral water samples and toy migration solutions., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) is a powerful method to determine the elemental composition of solid-state samples as it combines the high sensitivity and isotope selectivity of ICP-MS detection and the simplicity of laser ablation sampling. This technique enables rapid multiple sampling of the analysed material, such as needed for mapping or in-depth profiling applications. However, the duration of these measurements is practically restricted by the time taken for the particle to be transported from the sampling point to the ICP torch. The ablation cell, i.e. the sample holder, should combine high removal rate, high efficiency (i.e. complete transport of the ablated material) and reduced memory effects. These goals may be achieved by carefully designing the geometry of the cell and its gas flow patterns. A new cell design which enables a homogeneous wahout time of around 210 ms from a cylindrical chamber with 70 mm diameter is introduced in this paper. Washout time was determined as the time for the transient signal of 238U from a NIST610 glass standard to fall to 10% of its peak value. This result is achieved by combining a diffused, cylindrical flow pattern with an extraction tube coaxial with the laser beam and fixed to the laser assembly which enables the sampling point to be constantly positioned on the ablation spot. The lower part of the cell is mounted on the x,y stage for sample movement: the cell sealing is warranted by a viscous film junction between the lower and upper cell parts. Optimisation and performances of the apparatus are discussed in detail and performances are compared to existing designs., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Microwaves are widely used to assist digestion, general sample treatment and synthesis. The use of aqua regia is extensively adopted for the closed vessel mineralization of samples prior to trace element detection, leading to the contamination of microwave vessels by chlorine containing species. The latter are entrapped in the polymeric matrix of the vessels, leading to memory effects that are difficult to remove, among which the risk of silver incomplete recoveries by removal of the sparingly soluble chloride is the predominant one. In the present paper, we determined by mass spectrometry that hydrogen chloride is the species entrapped in the polymeric matrix and responsible for vessel contamination. Moreover, several decontamination treatments were considered to assess their efficiency, demonstrating that several cleaning cycles with water, nitric acid or silver nitrate in nitric acid were inefficient in removing chloride contamination (contamination reduction around 90%). Better results (≈95% decrease) were achieved by a single decontamination step in alkaline environment (sodium hydroxide or ammonia). Finally, a thermal treatment in a common laboratory oven (i.e. without vacuum and ventilation) was tested: a one hour heating at 150°C leads to a 98.5% decontamination, a figure higher than the ones obtained by wet treatments which requires comparable time. The latter treatment is a major advancement with respect to existing treatments as it avoids the need of a vacuum oven for at least 17h as presently proposed in the literature., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: To review current practice and update guidelines for the methodology of shortening composite measurement scales (CMSs)., Study Design and Setting: A literature review gathered data on 91 shortening processes from 1995 to 2009. The validity of the initial CMS, the shortening methods, and the validity of the derived short-form scales were examined. The results were compared with those from a previous literature review (articles from 1985 to 1995) to develop updated guidelines for CMS shortening., Results: The literature review revealed a persisting lack of use of rigorous methodology for CMS shortening. Of the 91 cases of CMS shortening, 36 combined a content approach and a statistical approach; 45 used only a statistical approach and 10 (11%) only a content approach. The updated guidelines deal with the validity and conceptual model of the initial CMS, the preservation of content and psychometric properties during shortening, the selection of items, and the validation of the short form., Conclusion: Item reduction based on a rigorous methodology is necessary if the short-form instrument aims to maintain the validity and other measurement properties of the parent instrument, which in turn supports application in research and clinical practice., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Cecal intubation is one of the targets of colon endoscopic evaluation, however even under experienced hands 5-10% of colonoscopies are incomplete., Aims: The aim of the study is to evaluate the usefulness of single balloon enteroscope (SBE) without employing overtube-balloon equipment in patients with incomplete colonoscopy., Methods: Between January 2009 and July 2010, patients with an incomplete standard colonscopy were prospectively enrolled to perform a colonoscopy with a single balloon enteroscope. Examinations were performed by the same expert operator during the same session., Results: Enteroscopy was performed on 79 patients, cecal intubation were obtained in 93.6% of the cases (74/79). It provided a new diagnosis in 43% of cases (34/79). Procedure was safe and well tolerated. Overall the additional use of single balloon enteroscope allowed to obtain the cecal intubation in up to 99.2% cases (898/905)., Conclusions: The use of the enteroscope without overtube-balloon equipment may be an effective method to increase the cecal intubation rate after failure of a standard colonoscopy., (Copyright © 2011 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

A number of patients with Parkinson's Disease (PD) complain of painful sensations that might be related not only to peripheral factors (muscle spasms, postural abnormalities) but also to an abnormal processing of nociceptive inputs in the Central Nervous System (CNS). To test this hypothesis, we recorded scalp CO(2) laser evoked potentials (LEPs) to foot skin stimulation in 11 pain-free treated PD patients affected by hemiparkinson (during the off state), in 6 pain-free drug-naïve hemiparkinsonian patients and in 11 healthy subjects. After each LEP recording, both patients and controls were asked to rate pain due to laser stimuli. In all subjects, CO(2) laser stimulation gave rise to a main negative N2 potential followed by a positive P2 response at vertex peaking at a latency of about 250 and 350 ms respectively which are thought to originate from several brain structures devoted to nociceptive input processing, including the cingulate gyrus and insula. ANOVA showed that the N2/P2 amplitude was significantly lower and pain rating significantly increased in treated PD patients than in controls in both the affected and unaffected sides, while in drug-naïve PD patients the reduction of the N2/P2 amplitude and the increase in pain rating were observed only in the affected side. These results suggest that in pain-free PD patients there is an abnormal nociceptive input processing that may be independent of the clinical expression of parkinsonian motor signs.

Poor recoveries are obtained if the BCR three-step sequential extraction is applied to 100 mg specimens rather than to 1 g. It is observed that analytes are lost during each phase separation which is carried out via centrifugation and can be hardly quantitatively performed on 100 mg sediment specimens. An alternative procedure, which is carried out on a single empty SPE column and involves separation by filtration, is developed to solve this problem. The proposed method is validated on 100 mg samples of certified sediment (BCR-701), but could be potentially used for even lower sediment specimens. Problems related to pH stability during step 2 and its influence on recoveries is also reported.

The development and validation of a method for the determination of mercury in sediments using a sector field inductively coupled plasma mass spectrometer (SF-ICP-MS) for detection is described. The utilization of isotope dilution (ID) calibration is shown to solve analytical problems related to matrix composition. Mass bias is corrected using an internal mass bias correction technique, validated against the traditional standard bracketing method. The overall analytical protocol is validated against NRCC PACS-2 marine sediment CRM. The estimated limit of detection is 12ng/g. The proposed procedure was applied to the analysis of a real sediment core sampled to a depth of 160m in Lake Como, where Hg concentrations ranged from 66 to 750ng/g.

A prototype DRIFTS flow reaction chamber was designed and developed in order to find analytical application in the study of heterogeneous catalysts operating at high temperatures under fast transient gas feed conditions. Minimisation of dead-volumes allows gas replacement in 8-10s at 10mLmin(-1) total flow. To overcome problems related to the reactivity of the cell walls under alternating oxidizing/reducing gases, the cell was built with Inconel 600trade mark, which was tested to be very inert even at high temperatures. The sample holder, which was developed to closely resemble a micro plug-flow reactor, poses some problems in terms of heat transfer to the outer body of the cell (limiting then the maximum reachable temperature) and of the correct measurement of the actual sample temperature. These problems were solved with a careful re-design of the upper part of the cell. The second prototype thus derived is able to reach temperatures up to 803K and allows gas replacement in less than 4s at 10mLmin(-1). The cell is inserted in a MCT-FT-IR, which allows to collect high quality spectra with a 1s time-resolution. The downstream flow can be analysed by a quadrupole mass spectrometer equipped with an enclosed source and by a commercial GC. The performances of this prototype cell are presented showing some tests carried out with ceria-zirconia (Ce(x)Zr(1-x)O(2)) catalysts for CO abatement under real operando conditions.

A sensitive, reproducible and easily performed enzyme immunoassay (EIA) based on a sandwich technique is described for serological detection of HBeAg and anti-HBe. EIA appears to be 600 times more sensitive than immunodiffusion and counterimmunoelectrophoresis and its performance compares well with available radioimmunoassays.