Indirect Technique Research Articles

Constraining gravitational-wave backgrounds from conversions into photons in the Galactic magnetic field

High-frequency gravitational waves (f≳1 MHz) may provide a unique signature for the existence of exotic physics. The lack of current and future gravitational-wave experiments sensitive at those frequencies leads to the need of employing different indirect techniques. Notably, one of the most promising ones is constituted by graviton-photon conversions in magnetic fields. In this work, we focus on conversions of a gravitational-wave background into photons inside the Milky Way magnetic field, taking into account the state-of-the-art models for both regular and turbulent components. We discuss how graviton-to-photon conversions may lead to imprints in the cosmic photon background spectrum in the range of frequencies f∼109–1026 Hz, where the observed photon flux is widely explained by astrophysics emission models. Hence, the absence of any significant evidence for a diffuse photon flux induced by graviton-photon conversions allows us to set stringent constraints on the gravitational-wave strain hc, strengthening current astrophysical bounds by ∼1–2 orders of magnitude in the whole range of frequencies considered. Published by the American Physical Society 2024

MODERNIZING CLASSICAL OPTIMAL CONTROL: HARNESSING DIRECT AND INDIRECT OPTIMIZATION

An introduction to optimal control, a fundamental concept in engineering and science disciplines, is a process of finding ways of controlling dynamic systems in such a way that they achieve certain goals while being subjected to given state limitations. The conventional approaches developed in the past have been integral to solving optimal control problems, including the maximum principle belonging to Pontryagin and the dynamic programming method. While relatively straightforward, these methods are not always amenable to higher-dimensional scenarios, interacting forces, or other non-trivial constraints. This paper presents a new methodology to extend classical optimal control, considering both direct and indirect optimization techniques. The direct methods, Euler and Runge-Kutta, Trapezoidal, and Hermite-Simpson, do not require the explicit derivation of the analytical control laws to execute control trajectories. Semi-analytical techniques, such as the shooting method, are based the control laws on proposed adjoint differential equations. This paper presents the basic outline of the classical optimal control problem and discusses the direct and indirect optimization methods. It is illustrated by referencing various examples, like the fixed-rate royalty payment approach. After outlining each framework, we identify the positive and negative aspects of the approach in questions of consistency and performance. Finally, the problems on the synergy of direct and indirect methods are considered further, and areas of further development of the presented methods and their integration with the more sophisticated tools, such as machine learning are identified. It can be concluded that the approach of using both direct and indirect optimization methods presents great potential in modernizing the classical optimal control, which challenges the conventional techniques and indicates potential for further development of the control system optimization.

Evidence of renal tubular injury in canine patients after elective desexing.

To investigate the frequency of perioperative acute kidney injury (AKI) in American Society of Anesthesiologists (SA) Grade I canine patients undergoing elective desexing using urine microscopy techniques and assess if pre- and intraoperative factors affect risk of developing AKI. Prospective observational clinical study conducted between September 2020 and October 2020. University teaching hospital. Thirty-two female and four male dogs between 5 months and 5 years of age classified as ASA I undergoing elective desexing surgery. Urinalysis was performed preoperatively and 20-24 h postoperatively to identify markers of renal tubular injury (RTI), particularly the presence of granular and renal tubular epithelial cell (RTEC) casts on sediment analysis. Dogs underwent a full physical examination and a preoperative assessment including measurement of urine specific gravity (USG), packed cell volume (PCV), total plasma protein and serum creatinine (sCr) was conducted as a part of the desexing programme. Anaesthetic records were examined for any evidence of intraoperative hypotension, defined as a mean arterial pressure (MAP) of <60 mmHg for any duration of time. MAP was measured using an indirect oscillometric technique. For analysis, animals were subdivided into affected and nonaffected groups, with affected animals those that hadpostoperative increases in granular and RTEC casts. Categorical and comparative analyses were then performed between groups to identify associations of increased casts with pre-, intra- and postoperative variables. A frequency of RTI of 5.6% was identified. This was accompanied by a significant association between increases in casts with total duration (p = 0.027) and number (p = 0.016) of hypotensive episodes. RTI is an anaesthetic consideration in ASA I veterinary patients undergoing elective desexing surgery. The identification of an association between the total duration and number of hypotensive episodes and the frequency of RTI highlights the importance of early detection of hypotension along with prompt and effective intervention in veterinary patients.

Using Illustrated Children’s Book to Strength Fracted / Cracks Identity of (the Israeli) Children

Illustrations in children&amp;apos;s books serve as powerful aesthetic devices to address complex emotions and ideologies, particularly in war-torn regions. These visual narratives act as catalysts for moral, value-based, and political discussions, offering a wordless medium that invites diverse interpretations based on the observer&amp;apos;s perspective. This approach creates an open dialogue where there are no absolute right or wrong answers. Children&amp;apos;s literature, through its illustrations, becomes a significant agent of socialization. These books impart cultural values, ideological concepts, and political behavior patterns, functioning as tools for establishing culturally responsive pedagogy. The images discussed, while originating from Israeli children&amp;apos;s books predating the 2023 conflict, possess a timeless and universal quality that transcends their immediate context. Illustrations in children&amp;apos;s books can either complement or diverge from the accompanying text, offering varying degrees of precision or poetic license. They carry cultural connotations that encompass symbols, traditions, beliefs, behaviors, and values unique to a particular society, conveying information beyond the apparent narrative. The inherent power of illustration lies in its ability to communicate directly with young children, often without the need for adult mediation. In preschool literature, illustrations serve multiple functions: they parallel written words, demonstrate abstract concepts, provide concrete representations of characters and settings, emphasize or contradict textual elements, and expand the narrative through visual elements not present in the text. Moreover, illustrations possess a psychological-therapeutic function, contributing to indirect treatment techniques. Like all visual representations, they embody simplified messages and shape recognition, conveyed formally and tangibly, with each element having both conscious and unconscious effects on the Therapeutic visual qualities in illustrated books aim to capture emotional nuances, intensify expressions of feeling, and convey concepts that may be challenging to express verbally. This is achieved through original solutions such as symbolism and creative visual metaphors. In conclusion, illustrations in children&amp;apos;s books, particularly those addressing complex themes like war and fear, offer a unique and powerful medium for fostering understanding, encouraging dialogue, and providing emotional support. Their ability to transcend linguistic and cultural barriers makes them invaluable tools in shaping young minds and addressing challenging societal issues.

Tuning of modern speed drives using IFOC: A case study for a five-phase induction machine

Electric machines have existed since the beginning of the 19th century. Although variable-speed drive technology has evolved considerably during the last years, the indirect field-oriented control technique has been in use as a standard control method since the 1960s, using an outer speed loop and an inner current loop. This paper deals with the non-trivial problem of tuning the outer speed controller of modern variable-speed drives, where experimental results are provided to show the need for new tuning methods. The influence of non-modeled effects on the performance of the drive is illustrated considering the dynamical effect of the mechanical speed sensing procedure using optical devices. This effect has not been generally considered. However, it is shown that it has a notable effect on tuning for high performance drives. This is especially true when considering some figures of merits of relevance for drives, such as the torque ripple. A Pareto analysis is proposed to reveal trade-offs between typical figures of merit to establish new tuning methods. To focus our contribution, a five-phase induction drive is considered as the case study, using a finite-state model predictive controller for the stator current control and PI regulators for the outer speed control loop.

Increasing LNAPL density and viscosity are indicators of Natural Source Zone Depletion

Natural source zone depletion (NSZD) acts to reduce the mass and/or toxicity of light non-aqueous phase liquids (LNAPL) in the shallow subsurface. Several indirect measurement techniques are commonly used to estimate LNAPL mass depletion based on CO 2 generation by hydrocarbon mineralisation, heat production by exothermic biodegradation processes, and sub-surface gas concentration gradients. This paper presents data on LNAPL density and viscosity and shows changes that result from NSZD processes. Increasing trends in LNAPL density and viscosity were observed that provided a qualitative line-of-evidence for NSZD. When LNAPL density and viscosity were combined with contemporaneous LNAPL chemistry analysis it was possible to correlate changes in the physical properties to depletion of alkanes from the LNAPL in a manner that would inform a quantitative NSZD assessment. LNAPL density and viscosity measurements are relatively cheap and reproducible, and increasing trends in LNAPL density and viscosity provide additional lines-of-evidence for NSZD.

Tailored MXene-derived nano-heterostructure oxides for peroxymonosulfate activation in the treatment of municipal wastewaters.

Nowadays, in the field of environmental protection, a huge effort is focused on efficient and sustainable processes to treat wastewaters. The current study emphasizes the photocatalytic performance of TiNbOx, a nano-heterostructure material derived from the oxidation of (Ti0.75Nb0.25)2CTx MXene. The TiNbOx nano-heterostructure exhibited remarkable performance in the degradation of caffeine (CAF) and sulfamethoxazole (SMX) under UVA irradiation in the presence of peroxymonosulfate (PMS). Under optimal conditions, 0.2 g L-1 of TiNbOx, 0.5 mM PMS and 50 μM concentration of pollutants and natural pH of deionized water, we observed a complete degradation of SMX and 91% degradation of CAF. Scavenging studies provided evidence for the involvement of ˙OH and SO4˙- in the degradation of the pollutants, which was also supported by indirect techniques of electron paramagnetic resonance (EPR) spectroscopy. The degradation pathway of the pollutants was analyzed by liquid chromatography-mass spectrometry (LC-MS) and several mechanisms were suggested including hydroxylation and isoxazole ring-opening reactions. In addition, X-ray photoelectron spectroscopy (XPS) supported the proposed degradation mechanism. The reusability test underscored the high stability and efficiency of TiNbOx. Moreover, the significance of this research was emphasized by conducting degradation studies in tap water (TW) and tertiary effluents of the wastewater (WW) treatment plant in Bratislava. Under optimal conditions, 49% and 30% CAF were degraded in TW and WW, respectively, after 12 hours of reaction. For SMX, 68% and 67% degradations were obtained in TW and WW, respectively.

Peningkatan Hasil Belajar Siswa pada Pembelajaran Agama Katolik Melalui Metode Problem Based Learning Kelas IX SMP Negeri 2 Tujuh Belas Tahun 2024

This research aims to improve student learning outcomes in Catholic Religion learning through the application of the Problem Based Learning Method in Class IX students of SMP Negeri 2 Seventeen in 2024. The approach taken in this research is quantitative with Classroom Action Research (PTK) consisting of Planning, Carrying out learning, observations, group discussions, individual assignments/tests, group awards and determining individual and group grades. Research Subject: Class IX students of SMP Negeri 2 Seventeen. Data collection techniques Direct Observation Techniques, Indirect Observation Techniques, Direct Communication Techniques, Indirect Communication Techniques, Measurement/Test Techniques, Documentation Techniques which are expected to be able to show changes in the actions given. The data obtained was analyzed using descriptive statistics. This research consists of three cycles. In the first cycle the average student score was 6.79 or 68.42%, and the student score in the second cycle was 8.83 or 75.17%. Meanwhile, the average value in the third cycle was 9.05 or 93.75%. From the results of this research, it can be concluded that learning using the Problem Based Learning Method for Class IX students at SMP Negeri 2 Seventeen is able to improve the remaining learning outcomes so that they meet the Minimum Completeness Criteria (KKM).

Kemandirian Belajar dan Hubungannya dengan Hasil Belajar Siswa Kelas V Sekolah Dasar Negeri

This study was conducted to determine the relationship between self-directed learning and cognitive learning outcomes among fifth-grade students at State Elementary School 03 Pontianak Kota. Fifth-grade students at the school as the population, while the sample involving all 28 students in class V C which is determined by using purposive sampling technique based on recommendation of the principal. Data collection employed indirect communication techniques through a research questionnaire and documentary study techniques using formative assessment results of students' cognitive learning in the subject of Integrated Science and Social Studies (IPAS) on the topic of "How I Live and Grow". Data analysis was carried out using statistical analysis with a significance level of 5% which showed the results of correlation calculations worth 0.662 with the provision of r table worth 0.374. Because the results of the value correlation calculation &gt; r table, the conclusion that can be drawn is that there is a positive and significant relationship between self-direct learning and cognitive learning outcomes.

Categorizing E-cigarette-related tweets using BERT topic modeling

BackgroundSocial media platforms are critical channels for promoting e-cigarettes, particularly among youth, making analysis of their vast and diverse content essential for public health interventions. Prevalence rates of e-cigarette use are high and evidence suggests that social media are popular forums that promote e-cigarette use through direct and indirect marketing techniques. The volume and diverse nature of e-cigarette-related information on social media is challenging and may obfuscate public health prevention messaging. Traditional hand-coding methods are labor-intensive and limit scalability. In contrast, unsupervised machine learning approaches, such as topic modeling, allow for efficient analysis of large datasets, uncovering patterns and trends that manual methods cannot achieve at scale. The present study focused on ascertaining the extent to which themes and topics in tweets related to e-cigarettes can be successfully rendered into useful homogenous units using machine learning. A better understanding of current depictions and discussions around e-cigarette products and use on social media can inform public health counter messaging and policy interventions. MethodsWe used topic modeling (BERTopic) to iteratively derive vape-related tweet clusters and calculate the importance of particular words to these groupings. We conducted a qualitative content analysis to study clustered tweets. We also sought to determine the geographic locations of e-cigarette conversations using automated geoparsing methods, which translate toponyms in textual data into geographic identifiers, to attempt to infer the location of tweets. ResultsWe were able to successfully identify >100,000 tweets in broad thematic categories in English and Spanish. Our correlation and inter-topic map analysis of the machine-derived topics, which examines the relationships between topics, indicated that most of the topics were unique (correlation value < 0.5) and did not overlap with each other. We identified six topics: Flavors and Disposable Vapes, Cannabis, Vape Shops and Refillable Vapes, Vape Culture, Anti-vaping and Quitting, and Spanish Tweets and Vaping Nicotine. Further analysis of these topics using qualitative methods identified themes within each topic. For example, Category 6 (Spanish Tweets and Vaping Nicotine) included four topics focused on the health risks of vaping, personal motivations for vaping, and the regulation of vaping products. Using geoparsing, which automatically detects location information, we found that the United States had the highest number of tweets related to vaping. Discussion/conclusionResults underscore the possibility of leveraging BERTopic modeling to reduce large quantities of data to comprehensively describe and categorize myriad e-cigarette related messages to which social media users are exposed. This data reduction approach can be applied to various social media platforms to describe and categorize e-cigarette posts and thereby triangulate and validate findings. Thematic content analysis of the topics identified through this technique requires supervision and human inputs. Our approach provides a comprehensive understanding of the evolving e-cigarette discourse, informing public health counter-messaging and policy interventions. Moreover, findings support the need for regulation, such as reducing appealing flavors and suggest that social media can be used effectively to support public health messaging (i.e., quitting messages).

Technical examination, elemental analysis and conservation of the arm of a colossal bronze statue from Aegion at the conservation laboratories of the National Archaeological Museum at Athens

The bronze arm, belonging to a colossal statue (presented by A. G. Vordos in this volume), was examined at the Chemical-Physical Research &amp; Archaeometry Laboratory of the National Archaeological Museum (NAM) in Athens. According to prevailing methodology the examination comprised: macroscopic, microscopic and endoscopic examination, elemental analysis p-XRF, X-ray radiography, recording of ancient repairs. It is assumed that the arm was manufactured by the indirect lost wax casting technique and was found to contain an enormous amount of lead (av. 40.15 %), a fact that dates it to the late Hellenistic or Roman period. The arm was consequently conserved at the Metal Conservation Laboratory of the NAM and it has now been returned to the Ephorate of Antiquities of Achaia in Patras

Laser Scanning Morphometric Measurements of the Main Orbital Communications in Dry Human Skulls

Background and Objectives: This research investigated the morphometric dimensions of the optic foramen (OF), superior orbital fissure (SOF) and inferior orbital fissure (IOF), using indirect measurement techniques such as laser scanning, making it likely the first study of its kind. This study aimed to identify the morphometric variability of the main orbit communications and to highlight the differences between genders. Materials and Methods: The anthropometric study was conducted on sixty dry skulls (120 orbits) of adults aged between 20 and 70 years. Measurements of orbital communications were made using the RS6 laser scanner. The orbital parameters that were investigated are as follows: length and width of the SOF and IOF, and height and width of the OF. Results: In males, the average height of the OF was 8.27 mm and 8.13 mm in females, while the average width of the OF was 6.34 mm in males and 5.83 mm in females. The SOF average length was 21.09 mm in males and 17.58 mm in females. The widths of the SOF in the three thirds (anterior, middle and posterior) in males were 5.14/4.77/7.11 mm and 2.28/3.48/5.80 mm in females. The average length of the IOF was 33.05 mm in males and 32.30 mm in females. The widths of the IOF in the three thirds (anterior, middle and posterior) were 5.61/3.92/4.70 mm in males and 7.24/4.68/4.08 mm in females. Conclusions: The OF height and width were higher in males compared to females. The SOF length and width were higher in males compared to females. The IOF length was higher in males for the right orbit and higher in females for the left orbit. The IOF width for both orbits was higher in females in the anterior and middle third, and higher for males in the posterior third. Evaluation of dry skulls using laser scanning is reliable and recommended for data accuracy. Laser scanning can become a usable method for all indented and hard-to-reach regions of the cranial skeleton.

Accuracy assessment of UAV-based documentation of archaeological site: Kültepe-Kaneš

High quality 2D/3D metric documentation of archaeological sites is used in many different applications such as archaeological-heritage management, digital archaeological excavation planning, orthophotographic documentation, and ancient Digital Surfaces Models (DSM) research. Structure-from-Motion based photogrammetry (SfM) is an indirect geodesic measurement technique based on multiple view image processing using high-level automation techniques. Using SfM to generate the high accuracy 2D/3D data needed for digital documentation of archaeological cultural heritage is relatively practical, economical, and fast. Factors such as the number of ground control points and their distribution to the study area, the robustness of the camera system model parameters, and the analytical model of the photogrammetric triangulation method used affect the accuracy of the data produced using SfM-photogrammetry. Kültepe-Kaneš, the center of the ancient Kingdom of Kaneš, which is located in central-Anatolia, was an Assyrian Trade Colony active between ca. 2000 BC and 1700 BC. The site, which was the center of the Old Assyrian trade colonies in Anatolia and one of the most important sites in ancient history, has been under excavation for the last 75 years. In this paper, high accuracy digital documentation of the Kültepe-Kaneš archaeological excavation area was made using different SfM methods. Statistical analysis revealed no significant difference in accuracy between Real-Time Kinematic (RTK) and Post-Process Kinematic (PPK) methods for the study area. This suggests that either PPK, RTK, or aerial triangulation with Ground Control Points (GCPs) can be employed to generate orthophotos and DSMs for archaeological sites with relatively flat surface areas, as long as a sufficient number of uniformly distributed GCPs are used.

Investigating the immunological activity of the Hsp70-P113 fusion protein for Mycoplasma ovipneumoniae detection: a groundbreaking study

BackgroundMycoplasmal pneumonia of sheep and goats (MPSG) is an important infectious disease that threatens sheep and goat production worldwide, and Mycoplasma ovipneumoniae (Movi) is one of the major aetiological agents causing MPSG. The aim of this study was to investigate the immunological activity of the Hsp70‒P113 fusion protein derived from Movi and to develop a serological assay for the detection of Movi.MethodsThis study involved codon optimization of the dominant antigenic regions of Movi heat shock protein 70 (Hsp70) and adhesin P113. Afterwards, the optimized sequences were inserted into the prokaryotic expression vector pET-30a( +) through tandem linking with the aid of a linker. Once a positive recombinant plasmid (pET-30a-rHsp70-P113) was successfully generated, the expression conditions were further refined. The resulting double gene fusion target protein (rHsp70‒P113) was subsequently purified using ProteinIso® Ni–NTA resin, and the reactivity of the protein was confirmed via SDS‒PAGE and Western blot analysis. An indirect enzyme-linked immunosorbent assay (i-ELISA) technique was developed to detect Movi utilizing the fusion protein as the coating antigen. The specificity, sensitivity, and reproducibility of all methods were assessed after each reaction parameter was optimized.ResultsThe resulting rHsp70-P113 protein had a molecular weight of approximately 51 kDa and was predominantly expressed in the supernatant. Western blot analysis demonstrated its favourable reactivity. The optimal parameters for the i-ELISA technique were as follows: the rHsp70-P113 protein was encapsulated at a concentration of 5 μg/mL; the serum was diluted at a ratio of 1:50; the HRP-labelled donkey anti-goat IgG was diluted at a ratio of 1:6,000. The results of the cross-reactivity assays revealed that the i-ELISA was not cross-reactive with other goat-positive sera against Mycoplasma mycodies subsp. capri (Mmc), Mycoplasma capricolum subsp. capripneumoniae (Mccp), Mycoplasma arginini (Marg), orf virus (ORFV) or enzootic nasal tumour virus of goats (ENTV-2). The sensitivity of this method is high, with a maximum dilution of up to 1:640. The results of the intra- and inter-batch replication tests revealed that the coefficients of variation were both less than 10%, indicating excellent reproducibility. The analysis of 108 clinical serum samples via i-ELISA and indirect haemagglutination techniques yielded significant findings. Among these samples, 43 displayed positive results, whereas 65 presented negative results, resulting in a positivity rate of 39.8% for the i-ELISA method. In contrast, the indirect haemagglutination technique identified 20 positive samples and 88 negative samples, resulting in a positivity rate of 18.5%. Moreover, a comparison between the two methods revealed a conformity rate of 78.7%.ConclusionThe results obtained in this study lay the groundwork for advancements in the use of an Movi antibody detection kit, epidemiological inquiry, and subunit vaccines.

TÉCNICAS CIRÚRGICAS PARA ESTÉTICA GENGIVAL E PERFIL EMERGENTE EM IMPLANTODONTIA

Introduction: Implant dentistry seeks to improve the similarity of implants with natural teeth, focusing on soft tissue quality, authentic gingival shape and adequate crown. The emergence profile plays a vital role in implant esthetics, guiding the soft tissues and preventing food accumulation. Direct and indirect techniques manipulate tissue to create the emergence profile using grafts and temporary abutments. Connective grafts and PRF are options to improve the gingival phenotype, with standard CTG and PRF promising to treat peri-implant diseases. Choosing the right techniques is crucial to restoring the patient’s anatomical profile. This study explores the main surgical techniques for gingival aesthetics and the emerging profile in implant dentistry. Objectives: To address the main surgical techniques for gingival aesthetics and the emerging profile in implant dentistry. Results: 27 articles were obtained, 2 (by duplicity), 20 (by abstract) and 1 (by not meeting the eligibility criteria) were excluded. Finally, 4 articles were included in this review. Discussion: the appropriate surgical technique promotes an adequate emergency aesthetic profile that reduces the time of the clinical procedure and obtains the best osseointegration associated with a peri-implant tissue, stable, healthy, with ideal and safe extensions. Thus achieving longevity in protection and gingival health. Conclusion: The choice of surgical technique depends on the individual characteristics of each patient, and the anatomical and aesthetic aspects of the patient must be considered in order to create an emerging profile that is aesthetically healthy and functionally healthy.

The effectiveness of direct versus indirect restoration techniques following canal therapy

The restoration of endodontically treated teeth is a critical aspect of dental practice, with the choice between direct and indirect restoration techniques being central to optimizing clinical outcomes. Direct restorations, such as composite resins, offer advantages in terms of cost, time efficiency, and preservation of tooth structure. However, their long-term performance, particularly in posterior teeth, may be compromised by issues such as marginal leakage, wear, and discoloration. Indirect restorations, including crowns, onlays, and inlays, provide enhanced durability, fracture resistance, and aesthetic outcomes, particularly for teeth that have undergone significant structural loss. These restorations, often made from ceramics or metals, offer superior longevity but come with higher costs and longer treatment times. The aesthetic performance of restorations plays a significant role in patient satisfaction. While direct restorations allow for immediate aesthetic adjustments and are generally more affordable, they may suffer from discoloration and wear over time. Indirect restorations, particularly porcelain-based options, offer better color stability and natural appearance, making them a preferred choice for patients with high aesthetic demands. Cost-effectiveness is another critical factor influencing clinical decision-making. While direct restorations are more affordable initially, their long-term cost-effectiveness may be compromised by the need for repairs or replacements. Indirect restorations, despite their higher upfront cost, often prove to be more economical in the long run due to their durability and reduced need for maintenance. The decision between direct and indirect restoration techniques should be individualized, considering factors such as tooth location, the extent of damage, aesthetic requirements, and financial constraints. A comprehensive evaluation of these factors, along with clear communication with the patient, is essential for achieving optimal clinical outcomes. Indirect restorations generally offer better long-term performance, particularly for heavily compromised teeth, while direct restorations remain a viable option for cases where cost and time efficiency are prioritized.

Prevalence estimates for COVID-19-related health behaviors based on the cheating detection triangular model

BackgroundSurvey studies in medical and health sciences predominantly apply a conventional direct questioning (DQ) format to gather private and highly personal information. If the topic under investigation is sensitive or even stigmatizing, such as COVID-19-related health behaviors and adherence to non-pharmaceutical interventions in general, DQ surveys can lead to nonresponse and untruthful answers due to the influence of social desirability bias (SDB). These effects seriously threaten the validity of the results obtained, potentially leading to distorted prevalence estimates for behaviors for which the prevalence in the population is unknown. While this issue cannot be completely avoided, indirect questioning techniques (IQTs) offer a means to mitigate the harmful influence of SDB by guaranteeing the confidentiality of individual responses. The present study aims at assessing the validity of a recently proposed IQT, the Cheating Detection Triangular Model (CDTRM), in estimating the prevalence of COVID-19-related health behaviors while accounting for cheaters who disregard the instructions.MethodsIn an online survey of 1,714 participants in Taiwan, we obtained CDTRM prevalence estimates via an Expectation-Maximization algorithm for three COVID-19-related health behaviors with different levels of sensitivity. The CDTRM estimates were compared to DQ estimates and to available official statistics provided by the Taiwan Centers for Disease Control. Additionally, the CDTRM allowed us to estimate the share of cheaters who disregarded the instructions and adjust the prevalence estimates for the COVID-19-related health behaviors accordingly.ResultsFor a behavior with low sensitivity, CDTRM and DQ estimates were expectedly comparable and in line with official statistics. However, for behaviors with medium and high sensitivity, CDTRM estimates were higher and thus presumably more valid than DQ estimates. Analogously, the estimated cheating rate increased with higher sensitivity of the behavior under study.ConclusionsOur findings strongly support the assumption that the CDTRM successfully controlled for the validity-threatening influence of SDB in a survey on three COVID-19-related health behaviors. Consequently, the CDTRM appears to be a promising technique to increase estimation validity compared to conventional DQ for health-related behaviors, and sensitive attributes in general, for which a strong influence of SDB is to be expected.

Contaminant mass discharge estimation of a sulfonamide plume by use of hydraulic profiling tool (HPT) and fluorescence techniques

The contaminant mass discharge is a relevant metric to evaluate the risk that a groundwater plume poses to water resources. However, this assessment is often vitiated by a high uncertainty inherent to the assessment method and often limited number of measurement points to carry out the assessment. Direct-Push techniques in combination with profiling tools and dedicated sampling can be an interesting alternative to increase the measurement point density and hence reduce the mass discharge uncertainty. The main objective of our study was to assess if DP logging and sampling could be employed to get a reasonable estimate of contaminant mass discharge in a large sulfonamide contaminant plume (> 1500 m wide), compared to a more traditional approach based on monitoring wells. To do so, an Hydraulic Profiling Tool (HPT) logging with a dedicated site calibration was used to estimate the hydraulic conductivity field. The sulfonamide concentrations were inferred from the compound fluorescence properties measured by laboratory spectrofluorometry (λEx / λEm = 255/340 nm) and a dedicated log-log linear regression model. Our results show that HPT-derived hydraulic conductivity values are in good agreement with the monitoring well results, and within the order of magnitude reported in similar studies or indirect geophysical techniques. Fluorescence appears as a powerful proxy for the sulfonamide concentration levels. Ultimately, the contaminant mass discharge estimate from HPT and fluorescence techniques lies within a factor 2 from the estimate by monitoring wells, with 549 [274–668] and 776 [695–879] kg/yr respectively. Overall, this study highlights that DP logging tools combined with indirect methods (correlation with fluorescence) could provide a relevant contaminant mass discharge estimate for some optically active substances, given that a proper calibration phase is carried out.

An Introduction to Ventra: A Programmable Abdominal Phantom for Training, Educational, Research, and Development Purposes.

Intra-abdominal pressure (IAP) is a critical parameter in the care of critically ill patients, as elevated IAP can lead to reduced cardiac output and organ perfusion, potentially resulting in multiple organ dysfunction and failure. The current gold standard for measuring IAP is an indirect technique via the bladder. According to the Abdominal Compartment Society's Guidelines, new measurement methods/devices for IAP must be validated against the gold standard. This study introduces Ventra, an abdominal phantom designed to simulate different IAP levels, abdominal compliance, respiration-related IAP variations, and bladder dynamics. Ventra aims to facilitate the development and validation of new IAP measurement devices while reducing reliance on animal and cadaveric studies. Additionally, it offers potential applications in training and education for biomedical engineering students. This study provides a thorough explanation on the phantom's design and fabrication, which provides a low-cost solution for advancing IAP measurement research and education. The design concept, technical aspects, and a series of validation experiments determining whether Ventra is a suitable tool for future research are presented in this study. Ventra's performance was evaluated through a series of validation tests using a pressure gauge and two intra-gastric (Spiegelberg and CiMON) and two intra-bladder (Accuryn and TraumaGuard) pressure measurement devices. The mean and standard deviation of IAP recordings by each device were investigated. Bland-Altman analysis was used to evaluate bias, precision, limits of agreement, and percentage error for each system. Concordance analysis was performed to assess the ability of Ventra in tracking IAP changes. The phantom demonstrated excellent agreement with reference pressure measurements, showing an average bias of 0.11 ± 0.49 mmHg. A concordance coefficient of 100% was observed for the phantom as well. Ventra accurately simulated different abdominal compliances, with higher IAP values resulting in lower compliance. Abdominal volume changes showed a bias of 0.08 ± 0.07 L/min, and bladder fill volume measurements showed an average difference of 0.90 ± 4.33 mL for volumes ranging from 50 to 500 mL. The validation results were in agreement with the research guidelines of the world abdominal society. Ventra is a reliable tool that will facilitate the development and validation of new IAP measurement devices. It is an effective educational tool for biomedical engineering students as well.

Recent improvements in the novel approach to the fast detection of surface contaminations

Here, we present the idea behind a novel measurement system and the recent improvements in detecting surface contaminations using a tunable, very fast three-core quantum cascade laser (QCL) system. It is developed as a potential replacement for the old established double-wheel sampling system currently used to detect surface threats caused by hazardous, non-volatile chemical substances. The novel system design is based on an optical measurement principle, allowing standoff detection and identification, thus rendering ground contact unnecessary. One of the leading military requirements for a CBRN reconnaissance vehicle is a high marching speed; hence, this new system is designed to have an ultra-short acquisition time and an adequate spectral bandwidth for measurements in the mid-infrared (MIR). This innovative approach may replace the more cumbersome indirect detection techniques. We discuss the main advantages and evaluate possible application scenarios that we expect from this setup. Active IR backscatter spectroscopy generally permits the contactless identification of hazardous chemical substances on surfaces. Here, the design was optimized around an approximate measuring distance of decimeters. Using a monoaxial setup, the autofocus is less demanding than alternative approaches and even allows for rapid measurements of rough surfaces. We built the improved measurement system based on novel QCL modules that integrate micro-opto-electro-mechanical grating scanners (MOEMS) in an external cavity. These elaborate laser modules provide almost one kilohertz (kHz) spectral scan speeds and typically cover a spectral range of 200–300 cm-1, respectively. Furthermore, such modules achieve measurement times of as short as one millisecond per spectrum. The full spectral coverage of the system is realized by coupling several of such modules.