Instrumental Techniques Research Articles

Advancements in hyperpigmentation management: exploring conventional methods, phytoconstituents, novel approaches, and instrumental techniques

ABSTRACT Hyperpigmentation is a common dermatological condition characterized by the darkening of patches of skin compared to the surrounding areas. It can occur in individuals of all skin types and ethnicities, and is caused by an overproduction or accumulation of melanin, the pigment responsible for the color of our skin, hair, and eyes. This comprehensive overview aims to delve into the various types, causes, risk factors, clinical manifestations, diagnosis, and treatment options for hyperpigmentation. Additionally, it explores the global and national prevalence of hyperpigmentation, its etiology, pathophysiology and diagnosis and treatment strategies. Furthermore, examines the formulations and dosage forms used to treat hyperpigmentation, including their side effects. It also discusses combination drugs and their associated side effects, as well as novel drug delivery systems and nanocarriers employed in the treatment of hyperpigmentation, providing insight into future prospects in this field.

Microplastics influencing aquatic environment and human health: A review of source, determination, distribution, removal, degradation, management strategy and future perspective.

Microplastics (MPs) are produced from various primary and secondary sources and pose multifaceted environmental problems. They are of non-biodegradable nature and may stay in aquatic environments for a long time period. The present review has covered novel aspects pertaining to MPs that were not covered in earlier studies. It has been observed that several methods are being employed for samples collection, extraction and identification of MPs and polymer types using various equipment, chemicals and instrumental techniques. Aquatic species mistakenly ingest MPs, considering them prey and through food-chain, and then suffer from various metabolic disorders. The consumption of seafood and fish may consequently cause health implications in humans. Certain plasticizers are added during manufacturing to provide colour, durability, flexibility, and strength to plastics, but they leach out during usage, storage, and transport, as well as after entering the bodies of aquatic species and human beings. The leached chemicals (bisphenol-A, triclosan, phthalates, etc.) act as endocrine disrupting chemicals (EDCs), which effect on homeostasis; thereby causing neurotoxicity, cytotoxicity, reproductive problems, adverse behaviour and autism. Negative influence of MPs on carbon sequestration potential of water bodies is also observed, however more studies are required to understand it with a detail mechanism under natural conditions. The wastewater treatment plants are found to remove a large amount of MPs, but in turn, also act as significant sources of their release in sludge and effluents. Further, it is covered that how advanced oxidation processes, thermal- and photo-oxidation, fungi, algae and microbes degrade the plastics and increase their numbers in the surrounding environment. The management strategy comprising recovery of energy and other valuable by-products from plastic wastes, recycling and regulatory framework; are also described in detail. The future perspectives can be of paramount importance to control MPs generation and their abundance in the aquatic and other types of environments. The studies in future need to focus on advanced filtration techniques, advanced oxidation processes, energy recovery from plastic wastes and influences of MPs on carbon sequestration in aquatic environment and human health.

Green Investing and Corporate Environmental Violations: Do CEO Ability and Female Directors Matter?

ABSTRACTBuilding on the notion that organizations are congruence seeking systems, this study investigates the impact of green investing on corporate environmental violations (CEVs). The research sample consists of China's A‐share‐listed companies for the period 2009–2020. The study employs a robust analytical framework that integrates least squares dummy variable approach, different proxies for regressors and moderators, and instrumental variable technique. Based on the rigorous methods, empirical analysis reveals that green investing helps mitigate CEVs, aligning with the theoretical premise of environmental strategic congruence. The moderating results indicate that elevated CEO ability and a higher proportion of female directors on boards enhances strategic congruence and amplifies the alleviating effects of green investing on CEVs. Furthermore, cross‐sectional analysis suggests that the mitigating effect of green investing on CEVs is more pronounced for firms in sensitive sectors, state‐owned, and lacking internal controls for environmental, health, and safety. This research contributes nuanced insights on the role of strategic congruence in sustainable finance and governance and presents practical implications for policymakers, managers, and corporate leaders navigating the intricate landscape of environmental responsibility within an emerging market.

Development of Innovative Techniques for the Instrumentation of Composite and Wet on Wet Pavement Sections at MnROAD

Composite and wet on wet concrete pavements are a promising solution for the economical, sustainable and durable construction and renewal of highways. Wet-onwet pavements consist of Portland cement concrete (PCC)-over-PCC, with a relatively thin PCC layer placed wet on a wet thicker layer made of a less expensive PCC mixture. A composite pavement here will be referred to as, a relatively thin hot mix asphalt (HMA) layer placed over a less expensive PCC mixture. In order to acquire knowledge on the performance of these pavements, three heavily instrumented pavement sections were constructed at the Minnesota Road Research Facility (MnROAD) in May 2010. The purpose of the instrumentation is to establish the magnitude of the environmental loads that develop within these pavements and the response of the pavement to both these environmental loads as we as traffic loads. Without this, the development of a rational mechanistic-empirical design process is not possible. The instrumentation of PCC pavements constructed in two lifts has never been performed before and presents a surmountable challenge. Discussed below are novel instrumentation techniques that were developed to overcome these challenges.

Design of an efficient magnetic brush solid acid and its catalytic use in organic reactions

In this research, with the Green Chemistry approach, to load more sulfonic acid active sites on catalyst surfaces, a nanocomposite material based on core-shell magnetite coated with vinyl silane and a sulfonated polymeric brush-like structure is designed and synthesized as a new class of efficient solid acid catalysts, referred to as Fe3O4@VS-APS brush solid acid. The synthesized catalyst was comprehensively characterized by a range of instrumental techniques, including XRD, SEM, TEM, FT-IR, EDX, TGA, and VSM. The activity of the catalyst was evaluated in Biginelli, Strecker, and esterification reactions. The Fe3O4@VS-APS brush solid acid has special features, such as easy reusability when a simple magnet is used for four reaction runs, an appropriate balance between hydrophobic and hydrophilic properties on the catalyst surface, and effective catalytic performance in the production of 3,4-dihydropyrimidin-2-one(thione) derivatives, 2-phenyl-2-(phenylamino)acetonitrile and octyl acetate.

A Comprehensive Review of Solid Lipid Nanoparticles

Liposomes, polymeric nanoparticles, and emulsions are alternatives to other popular colloidal carriers. Because of its advantages, solid lipid nanoparticles were developed in the early 1990s, including controlled drug release, focused drug delivery, and outstanding durability. The many methods utilized to manufacture solid lipid nanoparticles and excipients, including the membrane contractor technique, are summarised in this article, along with their possible benefits and drawbacks. Solid lipid nanoparticle (SLN) stability relies on maintaining particle size, drug encapsulation, and integrity over time. Excipients like surfactants and lipids influence stability, preventing aggregation and oxidation. Drying techniques, such as spray drying and lyophilization, enhance stability by converting SLNs to solid forms, while lipid composition and drug-lipid compatibility are crucial factors. So, the instrumental techniques employed and the difficulties associated with SLN manufacturing are thoroughly examined. Particular focus is placed on the SLN release pattern and drug integration models in SLN. The main uses of SLNs, including targeted drug delivery, and the analytical approaches used in SLN assessments, are covered in detail. The main objective of this work is a thorough overview of solid lipid nanoparticles, including production methods, characterization, and routes of administration. A discussion of the components of the SLN delivery mechanism and the in vivo destiny of the carriers are also included.

Comparison of different characterization approaches for monoelemental calibration solutions at two national metrology institutes.

Monoelemental calibration solutions are the most common reference in elemental analysis, linking measurement results to the International System of Units (SI). National Metrology Institutes (NMI) prepare these solutions as certified reference materials (CRM) and determine their elemental mass fraction with high accuracy. Characterization with high accuracy is one of the most critical steps in CRM production. This report compares the approaches taken by the NMIs of Türkiye (TÜBİTAK-UME) and Colombia (INM(CO)) in preparing and characterizing cadmium calibration solutions with a nominal value of 1 g kg-1. Each NMI produced CRMs using an independent batch of cadmium calibration solution and assigned mass fraction values to both their own solutions and those of the other NMIs. TÜBİTAK-UME employed a primary difference method (PDM) to assess the purity of a cadmium metal standard, quantifying all possible impurities using a combination of instrumental analytical techniques. The defined purity standard was used for both the gravimetric preparation of the CRM and the calibration of high-performance inductively coupled plasma optical emission spectrometry (ICP-OES) measurements. On the other hand, INM(CO) used gravimetric titration with EDTA to assay cadmium in the CRM solutions. The EDTA salt was previously characterized by titrimetry. Despite the fundamentally different measurement methods and independent metrological traceability paths to the SI, the measurement results exhibited excellent agreement within the stated uncertainties. This comparative analysis demonstrates the effectiveness of varied characterization approaches and underscores the reliability of the cadmium calibration solutions prepared by TÜBİTAK-UME and INM(CO). This collaborative effort highlights the reliability and adaptability of various measurement techniques in fulfilling rigorous metrological standards for elemental calibration solutions. Furthermore, this approach enhances the robustness of the measurements in the field of elemental analysis and contributes traceability to the SI.

Navigated instrumentation and ligament tensioning device enhances initial gap acquisition during total knee arthroplasty procedure: A cadaveric study.

Gap-balanced total knee arthroplasty (TKA) technique relies on initial ligament evaluation, particularly in patient-specific implantation using computer-assisted technologies. This cadaveric study aimed to compare the reproducibility and reliability of medial and lateral gap measurements between manual stress testing and dynamic ligament balancer. Initial gap acquisitions were assessed from eight cadaveric knees (four specimens) during the same navigated TKA procedure by five differently skilled surgeons (three seniors and two juniors). Medial and lateral gaps were sequentially acquired from extension to maximum knee flexion, applying manual stress prior to any bone cuts (conventional technique), and using intra-articular tensioning device placed between the tibial cut and the native femur (instrumented technique). Reproducibility was assessed using intraclass correlation coefficient (ICC), stratified by the measurement technique, the type of gaps and the operator experience. Differences in gaps (mm) between techniques were assessed using the Bland and Altmann method. The instrumented technique showed higher ICCs than the conventional technique for medial and lateral gaps (0.87 vs. 0.60, P = 0.002, and 0.92 vs. 0.25, p < 0.0001, respectively), and showed no difference in ICCs between medial and lateral gap acquisitions (0.87 vs. 0.92, p = 0.8). Senior surgeons achieved higher ICCs than juniors, while non-significant with both techniques. Differences in gaps between techniques increased with knee flexion angle (0.8, 2.8 and 3.5 mm at 10°, 45° and 90° of flexion angle, respectively) and decreased with the operator experience (p = 0.003). The instrumented balancing technique offered better reproducibility than using manual valgus and varus stress, when measuring medial and lateral gaps. Tensioning devices may play a significant role in enhancing initial gap acquisition, disregarding the flexion angle and the operator experience. Level IV (observational study involving cadaveric specimens).

Cicatricial Tracheal Stenosis — A Long-Life Journey

Introduction. Since ancient times tracheostomy is known as a surgical procedure that ensures airway patency. According to current views, a non-idiopathic cicatricial tracheal stenosis develops within six weeks following the initiation of mechanical ventilation. When a patient presents with a characteristic history and complaints, the diagnosis of cicatricial tracheal stenosis poses no challenges.Aim. To present a series of observations of patients who underwent tracheostomy in childhood, whereas the cicatricial tracheal stenosis was diagnosed only in over 35 years after the onset of airway obstruction symptoms.Materials and methods. The study involved five patients (two men and three women) aged between 43 and 63 years. All patients had undergone tracheostomy in childhood, followed by subsequent decannulation. For over 35 years, the patients were monitored under the diagnosis of bronchial asthma. When a tracheal stenosis was identified, all patients underwent circular tracheal resection.Results and discussion. The duration of the surgical procedure ranged from 110 to 240 minutes. No complications that required re-surgery were recorded. All patients achieved healing of the tracheal anastomosis. The postoperative hospitalization period ranged from 10 to 15 days. The incidence of tracheal complications remains 0.2%–25%. The clinical onset of tracheal stenosis typically occurs within the first few months following decannulation. Functional diagnostic methods reveal a pattern of bronchial obstruction, which necessitates the administration of inhalation therapy using various groups of bronchodilator and anti-inflammatory medications. The most informative instrumental diagnostic techniques for tracheal diseases include laryngotracheoscopy and computed tomography.Conclusion. A history of tracheostomy or mechanical ventilation in patients presenting with complaints of dyspnea requires meticulous attention due to the risk of the development of cicatricial tracheal stenosis.

Paper-Based Device for Phenolic Content Determination in Tea Extracts.

Phenolic compounds garner interest in developing medicines, nutraceuticals, and cosmeceuticals based on natural products. The quantity of phenolic compounds in a sample is commonly determined via spectrophotometry; however, this instrumented technique is relatively laborious and time consuming and requires a large amount of reagents. This work aimed to develop a simple, point-of-need colorimetric sensor to rapidly determine total phenolic content (TPC) in tea extracts. We developed a radial paper-based analytical device (PAD) for TPC determination based on the established colorimetric reaction between the Folin-Ciocâlteu reagent and phenols. The PAD was designed to enable quantitative (with image capturing device and color processing software) and semiquantitative (using a color palette reference card) determinations. Analytical performance and stability of the PAD were evaluated based on the color responses. The PAD was successfully applied for the determination of phenolics in tea extracts obtained using several polar protic solvents, including water, methanol, and ethanol, with satisfactory accuracy (recovery of 95.5%-104%, 110%-116%, and 104%-110%, respectively) and precision (RSD < 9%). The obtained TPC values also agreed with those from visible spectrophotometry. Semiquantitative determination using the color reference card with three categories of TPC level (i.e., 0-100, 100-500, and 500-1000 mg gallic acid equivalent/L) provided > 95% accuracy. The devices were the most stable when stored at 4°C in a light-protected, vacuum-sealed container. The proposed PAD is promising for simple, rapid (~10-20 min), and accurate estimation of TPC in plant extracts.

Self-Reported Oral Hygiene Performance of Patients in Albania: A Questionnaire-Based Survey.

Background/Objectives: Oral hygiene is a key factor for dental and periodontal diseases and the prognosis of any treatment to restore their consequences. The present survey aimed to evaluate how well informed patients in Albania are on oral hygiene, given the scarce evidence on this topic. Methods: This survey was performed using a Google Forms questionnaire on oral hygiene habits, type and technique of instruments used, and frequency of dental recall visits. Results: A total of 1006 questionnaires were filled in a one-month time period (January 2020) from a population of 75.2% females and 24.8% males, 32.7 ± 11.3 years of age, from whom 94.6% reported a lack of systemic diseases and 80% were non-smokers. All of the population brushed their teeth at least once daily. The most used type of toothbrush was a manual one (91.1%) with medium-bristle hardness in 71% of cases. The most prevalent way of using the toothbrush was through circular movements (36.7%) with a duration of 2-3 min in 72% of the population. Only 77.1% of the population used interdental instruments, mainly interdental floss. Conclusions: Within the limits of this study, it could be concluded that the present population seemed to be mostly appropriately informed, but the information needs further revision and promotion by dentists.

The age-productivity profile: long-run evidence from Italian regions

Abstract This paper investigates the effects of demographic shifts on labor productivity by leveraging variation in the age structure of Italian regions. These effects are analyzed along a first channel – the direct relation between population age and productivity – and a second channel capturing the productivity implications of a more or less dispersed age distribution. We propose an estimation framework that relates regional productivity to the entire age distribution of the working-age population and use instrumental variable techniques to address endogeneity issues. The estimates yield a hump-shaped age-productivity profile peaking between 35 and 40 years. We also document non-linear effects of regional age dispersion on productivity.

Extraction of E171 or E172 food additives from sugar-based or lipid-based complex matrices for primary particles identification by electron microscopy

Measurement of primary particle size distributions is fundamental to determining if a material should be classified as a nanomaterial according to the European Commission recommended definition. This is of particular relevance to alimentary products, where current regulation requires that any additives containing nanoforms be explicitly declared as such in the ingredients’ list. Currently, Electron Microscopy is the only instrumental technique able to reliably classify materials as nanomaterials. To verify the nanostatus of a material using this technique, it is essential to firstly extract the additives from the matrix in which they are dispersed, and then measure a wide size distribution while avoiding artefacts from the food matrix. In this operating procedure, extraction protocols, developed and applied for sugar-based or lipid-based food, are described. In particular, case studies for titanium dioxide E171 and iron oxide/iron hydroxide based materials such as E172 are considered. The protocols are based on gentle extraction of the additive materials and could, in principle, be used for other nanomaterials provided they are not soluble in water or ethanol and are resistant to enzymatic reactions. The size distribution of the extracted material can then be determined from images acquired using scanning and/or transmission electron microscopy.

Thiol-Functionalized Cobalt Ferrite (CoFe2O4@MPTS) Nanoparticles as Cutting-Edge Adsorbents for Bovine Serum Albumin.

This paper describes the synthesis of CoFe₂O₄ nanoparticles via a simple ultrasonic-assisted co-precipitation method and their functionalization with thiol groups using (3-Mercaptopropyl)trimethoxysilane (MPTS) as the functionalizing agent. The use of ultrasonic energy not only serves as a green energy source but also reduces the reaction time fivefold compared to conventional methods. The synthesized CoFe₂O₄ nanoparticles were characterized for their surface and internal properties using instrumental techniques such as Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Vibrating Sample Magnetometer (VSM). The functionalized nanoparticles were applied for the effective adsorption of bovine serum albumin (BSA) from a buffered aqueous medium. To enhance the adsorption performance, the influence of pH, amount of solid adsorbent, initial BSA concentration, shaking time, and temperature on protein adsorption was investigated. Lagergren pseudo-second-order adsorption kinetics fitted the BSA adsorption data well, with an acceptable R² value of 0.976. Additionally, the BSA adsorption data were analyzed using Langmuir and Freundlich isotherm models, and it was concluded that the experimental data followed the Langmuir equation more closely than the Freundlich equation. At an initial pH of 5.57 (acetate buffer), the adsorption capacity (Q₀) for BSA protein was found to be 200mg/g. The thermodynamic study revealed ΔS° and ΔH° values of 17.40J/mol·K and - 45.37kJ/mol, respectively.

A Newly Developed Compressed Air Cannon Test Bench Designed for Multi-Impact Analysis of Composite Structures

Understanding the response and damage evolution of structures subjected to multiple impact events is essential for designing resilient structures capable of withstanding complex loading scenarios, such as impacts from hail, gravel or foreign object debris. This article presents the development and characterization of a novel test bench, the “Compressed air multi-cannon”, designed specifically for studying the multi-impact behavior of composite materials. This test bench offers advantages over traditional impact testing methods by enabling controlled and adjustable impact parameters, including number of impacts, spatial and temporal lag, energy, angle and impactor dimensions. The primary objective of this work is to provide a detailed description of the test bench design, construction, and validation procedures. Key components such as the pressurized air system, projectile launch mechanism, target mounting arrangement, and data acquisition system are discussed. Experimental methodologies for assessing multi-impact response, specimen preparation, instrumentation, and data analysis techniques are outlined. Through a series of single-impact and multi-impact tests, distinctive damage mechanisms and energy absorption characteristics were observed in composite structures, revealing significant differences in how composites respond under single- and multi-impact conditions. It was found that the single-impact configuration remains particularly critical compared to multi-impact configurations with a high number of impacts. However, further testing is required to determine whether this result holds true under varying impact parameters, highlighting the unique value of this machine for exploring new, realistic questions in the literature.

Alfred Kirstein-A pioneer of direct laryngoscopy

On 23 April 1895, the Berlin ENT medical specialist Alfred Kirstein performed the first direct examination of the larynx using a Casper esophagoscope equipped with electric lighting, which he called an "autoscope". The examination of the larynx, which had previously only been possible indirectly using mirror systems, was named by him "autoscopy". The development of the device enabled a more precise observation than before and laryngeal or tracheal foreign bodies could be removed better and more easily. The new instrumental development and examination technique he described met with rapid approval and great interest in specialist circles. Shortly afterwards the first publications on orotracheal intubation for anesthesia appeared in scientific journals, that should also be possible with the aid of Kirstein's autoscope. Although he never propagated this himself, it was also possible to perform these under visualization using atongue depressor equipped with alight, which he had developed ashort time later. Both developments are already very close to today's laryngoscopes. Kirstein's contribution in this respect has so far hardly been appreciated, especially in German-speaking countries.

Can Informal Care Be a Substitute for Formal Care? Evidence from Older People with Disabilities in Beijing, China

Background: The demand for long-term care is increasing as the elderly population continues to grow, prompting a critical examination of care modalities. Methods: This study employs data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) to assess the relationship between informal and formal care for older people with disabilities in Beijing. The analysis employs the Probit model and incorporates the application of instrumental variable techniques and propensity score matching to ensure robustness in the results. Results: The findings highlight the important role of informal care. Conclusions: Policymakers should incorporate support policies for informal care into the overall design of the system, provide support to informal caregivers, and reduce their burden. Our research conclusions provide empirical reference for cities with similar characteristics to Beijing.

The Reveal of Chinese Musical Technique “Run Qiang” in Bright Sheng’s Piano Works “My Song” and “My Other Song”

Bright Sheng (born. 1955), one of the representatives of the “New Wave” composers, has been trying to make a breakthrough in the fusion of Chinese and Western cultures in his works due to his childhood experiences and absorption of both Chinese and Western educational systems. “My Song” (1989) and “My Other Song” (2007) are two works for solo piano composed 18 years apart, in which the traditional Chinese instrumental or vocal technique “Run Qiang”润腔 is involved in both works. This paper emphasizes Sheng’s compositional style and the concept of “fusion” of Chinese and Western cultures in his musical works by analyzing how the elements of traditional Chinese “Run Qiang” in these two works that are fused with Western compositional techniques.

Navigated versus conventionally instrumented total knee arthroplasty techniques: No difference in functional alignment or balance.

Much debate exists about the superiority of navigated versus conventional instrumentation for achieving optimal balance and alignment during total knee arthroplasty (TKA). Recent registry data indicate no long-term survivorship benefit for TKAs performed using technology assistance, despite the added resource and financial costs. However, outcome comparisons are confounded by varying surgeon techniques and targets for ideal balance and alignment. This study aimed to investigate alignment or balance outcome differences between navigated and conventionally instrumented TKAs performed using an identical operative sequence and alignment strategy. Fifty navigated and 50 conventionally instrumented primary TKAs, using an identical inverse kinematic alignment strategy, were included. Navigation equipment was used intraoperatively to 'post-cut' record the conventionally instrumented TKAs. Intraoperative balance, range, and alignment; and post-operative radiographic accuracy for restoration of constitutional alignment were compared. Forty-nine navigated and 49 conventionally instrumented TKAs were compared (n = 2 excluded due to inadequate radiographs). No preoperative demographic or deformity severity differences existed. No intraoperative balance, range or alignment difference existed. Neither technique was more accurate for restoration of constitutional alignment. Whilst large registry data may be confounded by uncaptured variables such as surgeon balancing techniques or surgeon alignment strategy preferences, this study found no alignment or balance differences between navigated versus conventionally instrumented TKA techniques for a surgeon and technique-controlled study. Although the increased resources necessary for technology assistance are not justified by this study, further studies may identify significance using larger samples or comparison of alternative outcomes. Level II.

Effect of nutritional supplements on the physico-structural and sensory characteristics of low-fat camel milk yogurt.

This study aimed to elucidate the effects of various nutritional supplements on the physical, structural and sensory attributes of low-fat yogurt derived from camel milk, with the longer-term objective of enhancing its appeal and suitability for elderly consumers. Fresh camel milk was obtained from an Australian farm. Two yogurt variants were created: plain yogurt (CMY) and yogurt with added fructooligosaccharides, microbial transglutaminase (a ubiquitous food additive with potential health risks), apple pectin and linseed oil (CMYWA). The syneresis index of these yogurts was quantified through centrifugation, colour changes due to additives were assessed via colorimetric methods and both viscosity and granulometry were determined using precise instrumental techniques. After 7 d refrigerated storage, syneresis was 50% in CMY vs. 30% in CMYWA. Viscosity on day 7 was 205 mPa.s for CMYWA vs. 110 mPa.s for CMY. The CMYWA granule size increased from 2.1 μm on day 0 to 2.8 μm on day 14, while CMY granule size remained stable around 1.9 μm. Lactobacilli counts were higher in CMYWA at 2.8 × 107 CFU/g vs. 2.3 × 106 CFU/g in CMY. In a paired preference test with 37 consumers aged 18-65, CMYWA was significantly preferred over CMY. Sensory evaluations further substantiated that the yogurts with added supplements were more appealing to the palate. The results demonstrate the supplements improved camel milk yogurt properties.