Additional Tests Research Articles

Combinatorial prediction of therapeutic perturbations using causally-inspired neural networks.

Phenotype-driven approaches identify disease-counteracting compounds by analyzing the phenotypic signatures that distinguish diseased from healthy states. These approaches can guide the discovery of targeted perturbations, including small-molecule drugs and genetic interventions, that modulate disease phenotypes toward healthier states. Here, we introduce PDGrapher, a causally inspired graph neural network (GNN) designed to predict combinatorial perturbagens (sets of therapeutic targets) capable of reversing disease phenotypes. Unlike methods that learn how perturbations alter phenotypes, PDGrapher solves the inverse problem of directly predicting the perturbagens needed to achieve a desired response. PDGrapher is a GNN that embeds disease cell states into gene regulatory or protein-protein interaction networks, learns a latent representation of these states, and identifies the optimal combinatorial perturbations that most effectively shift the diseased state toward the desired treated state within that latent space. In experiments in nine cell lines with chemical perturbations, PDGrapher identified effective perturbagens in up to 13.33% more test samples than competing methods and achieved a normalized discounted cumulative gain of up to 0.12 higher to classify therapeutic targets. It also demonstrated competitive performance on ten genetic perturbation datasets. A key advantage of PDGrapher is its direct prediction paradigm, in contrast to the indirect and computationally intensive models traditionally employed in phenotype-driven research. This approach accelerates training by up to 25 times compared to existing methods. PDGrapher provides a fast approach for identifying therapeutic perturbations and advancing phenotype-driven drug discovery.

Development of Homogeneous Carboxylation of Phenolates via Kolbe-Schmitt Reaction.

In this study, the homogeneous carboxylation of potassium, sodium, and lithium phenolates in DMSO solution at 100 °C by the Kolbe-Schmitt reaction was investigated. The impact of water, phenolate concentration, and cation nature on the yield of products and reaction selectivity was demonstrated. Based on the patterns observed, it was concluded that a complex cluster mechanism governs the carboxylation reaction in the solution. The use of a homogeneous reaction medium allowed for convenient testing of various additives to assess their impact on the reaction. Basic additives such as sodium salts of mesitol, tert-butylcalix[4]arene, sodium isopropyl, and tert-butyl cabonates were found to enhance the reaction, increasing the yield of hydroxybenzoic acids by 20% (to 61.6%). The main product in the DMSO solution was identified as 4-hydroxybenzoic acid, in contrast to the classical Kolbe-Schmitt method which typically yields 2-hydroxybenzoic (salicylic) acid. The use of 13C NMR spectroscopy enabled the observation of a "carbonate complex" in the solution for the first time, with the carbonate carbon displaying a chemical shift value of 142 ppm, an unusual finding for stable carbonates, and located between the signals of free dissolved CO2 and carboxylate derivatives.

New Fuels and Advanced Combustion Modes for Innovative Internal Combustion Engines: An Overview

Internal combustion engines (ICEs) currently account for approximately 25% of global power generation. Notably, this technology still plays a crucial role in a large segment of the transportation sector. In this editorial, a short overview of the latest developments and current research trends related to internal combustion engines is presented. Furthermore, the 11 contributions of this Special Issue are introduced. They cover three main topics: the use of new fuels for internal combustion engines for both automotive and railway applications; testing of additives for ICEs fed with conventional fuels; and CFD simulation applied to the analysis and design of ICE components.

Adaptation and validation of the Turkish version of the Bolton Compassion Strengths Indicators scale among nursing students: A psychometric analysis.

The study used a methodological design to adapt a Turkish translation and validate the Bolton Compassion Strengths Indicators scale. The sample of the study consisted of 500 nursing students. Partial least squares structural equation modelling was used to analyze the construct and internal validiy. The values of average variance explained were analyzed for convergent validity. Tukey's test of additivity examined the additivity, and Hotelling's T2 test examined the mean difference between items. Internal consistency and test-retest reliability were ensured for reliability. Test and retest scores were compared by applying the paired samples t-test and Wilcoxon test, and the fit was analyzed through the intra-class correlation coefficient. The Turkish version of the scale consisted of 34 items and 8 subscales. The Cronbach's alpha coefficient of the overall scale was 0.954. The scale was highly reliable and displayed psychometric solid properties. It has been determined that the Turkish version of the Bolton Compassion Strengths Indicators scale is a comprehensive, easy-to-understand measurement tool with a broad perspective that can be safely applied to future nurse candidate students. The scale has been evaluated as a reliable measurement tool that can provide cross-cultural measurement.

Non-inferiority trial in veal calves on the efficacy of oxytetracycline and florfenicol treatment for pneumonia guided by quick thoracic ultrasound

Purchase dependent calf rearing systems, such as the white veal industry, systematically rely on antimicrobial mass medication (metaphylaxis) to counter respiratory tract infections. Despite mounting criticism, the industry fears that without metaphylaxis, mortality would drastically increase. This randomized clinical trial aimed to compare the efficacy of a quick thoracic ultrasonography (qTUS) individualized treatment length between oxytetracycline (OTC) and florfenicol (FF). Regression of maximum consolidation depth <1 cm was used as a criterion for cure and to stop antimicrobial treatment. Additionally, the study assessed the associations of consolidation depth at treatment initiation with cure and treatment duration. The trial involved 320 veal calves, randomly assigned into one of 2 groups: one receiving OTC (n = 160) and the other FF (n = 160) on d 1 (2-d metaphylaxis). Clinical scoring and qTUS were done on d 1 and every 48 h for a 10-d period. After d 1, only calves with consolidations ≥1cm were given further treatment. On each time point, maximum consolidation depth was used to categorize calves into 4 qTUS categories: healthy (no consolidation), mild pneumonia (consolidation <1 cm), moderate pneumonia (consolidation 1-3 cm) and severe pneumonia (consolidation ≥3 cm). Cure, treatment duration and the number of antimicrobial dosages (NAD) were compared between treatment groups. In addition, pathogen identification and antimicrobial susceptibility testing was performed on isolates from nonendoscopic broncho-alveolar lavage fluid. On d 1, 30.0% (96/320) of the calves had consolidation ≥1cm, which increased to 50.9% (162/318) by d 9. After single metaphylactic treatment, cure was 20.9% (9/43) and 20.9% (9/43) in the OTC and FF group, respectively. Calves with severe pneumonia had lower odds to be cured after first treatment than calves with moderate pneumonia (odds ratio = 0.17; 95% CI: 0.04-0.63). By d 9, final cure of the initial cases was 27.9% in both the OTC and FF groups. In both groups, cure was similar at all observation points. Overall, final cure of all calves with either moderate or severe pneumonia during the trial was 41.2% (52/102) and 19.0% (12/63), respectively. Median (Med) treatment duration was 4 d (interquartile range [IQR] = 2-6; minimum [Min] = 2; maximum [Max] = 8) and was similar in both treatment groups. Treatment duration for calves with moderate pneumonia (Med = 6; IQR = 4-6; Min = 2; Max = 8) was lower than the median treatment duration of calves with severe pneumonia (Med = 8; IQR = 4-8; Min = 2; Max = 8). When compared with calves with mild pneumonia on d 1, calves with moderate and severe pneumonia had significantly longer treatment durations. In this study, cure was low and not different between both antimicrobials. Categorizing calves based on consolidation depth appears useful as both cure and treatment duration were different for the mild, moderate, and severe groups.

Mendelian randomization analysis of psoriasis and psoriatic arthritis associated with risks of ulcerative colitis.

This study is designed to explore the potential causal relationship between psoriasis and psoriatic arthritis (PsA) while investigating the genetic basis shared by these inflammatory diseases. Significant single nucleotide polymorphisms (SNPs) associated with UC, psoriasis, and PsA were selected as genetic instrumental variables using Genome-Wide Association Study (GWAS) datasets. Additionally, Mendelian randomization (MR) methods, including inverse-variance weighting (IVW), MR-Egger regression, and Weighted Median (WME), were utilized to evaluate the causal relationships between these diseases. Moreover, sensitivity analysis and heterogeneity testing were conducted to validate the stability of the results. A total of 123 significant SNPs associated with psoriasis, PsA, and UC were identified as genetic instrumental variables based on GWAS datasets. The analysis revealed a 36% increased risk of UC with psoriasis (odds ratio [OR]=1.350, 95% confidence interval [CI]=1.065-1.729, P=0.012) and a 32.9% increased risk of UC with PsA (OR=1.329, 95% CI=1.176-1.592, P<0.001). Further analysis showed a 43.5% increased risk of psoriasis with UC (OR=1.435, 95% CI=1.274-1.831, P<0.001) and a 45.8% increased risk of PsA with UC (OR=1.458, 95% CI=1.166-1.822, P=0.0013). In addition, sensitivity analysis and heterogeneity testing demonstrated the high stability of these results. Particularly, neither MR-Egger regression analysis nor leave-one-out analysis revealed significant heterogeneity or pleiotropy bias, indicating the reliability of these causal estimates. Moreover, the use of the MR-PRESSO further confirmed the positive correlation between psoriasis and UC, and the corrected estimates remained consistent with IVW analysis results after excluding potential outlier SNPs, enhancing the credibility of the analysis. This study strengthens the understanding of the genetic and causal relationships among UC, psoriasis, and PsA through GWAS and MR methods, revealing the genetic basis they may share. These findings not only provide a novel perspective on the comorbidity mechanisms of these diseases but also offer a valuable reference for the development of future treatment strategies and intervention measures.

Triphenylamine based oxime ester photoinitiator for LED-induced free radical photopolymerization and 3D printing

Triphenylamine based oxime ester photoinitiator for LED-induced free radical photopolymerization and 3D printing

Postpartum Excessive Social Support Scale: A Scale Development and Psychometric Testing Study.

In Turkey and other collectivist cultures, child-rearing is a communal effort provided by multiple family members, especially female relatives such as mothers-in-law, aunts, and sisters. Environments with excessively controlling social factors can adversely affect their maternal roles. This study was conducted to develop a measurement tool for determining postpartum excessive social support. This is a scale development and psychometric evaluation study. In the study, a draft of the Postpartum Excessive Social Support Scale (PESSS) was created, subsequently submitted to expert opinion, and administered to mothers in the postpartum period of 1 to 6 weeks online between March and December 2023 (n = 440). A factor analysis (including explanatory factor analysis [EFA] and confirmatory factor analysis) was conducted to determine the construct validity of the scale, while Cronbach's alpha was examined to establish its reliability. Response bias (Hotelling T2) and additivity (Tukey's test of additivity) of the scale were also determined in the study. For the content validity of the scale, 10 experts from the field of midwifery were consulted (content validity index [CVI] = 0.80). As a result of the EFA, Kaiser-Meyer-Olkin value was found as 0.916. Through factor analysis using the direct oblimin rotation technique, a four-factor structure was identified for the scale, explaining 64.197% of the total variance (social pressure, effect of environmental factors on paternal role, effect of environmental factors on maternal role, and barriers in mother-infant interaction). The internal reliability coefficient of the scale was highly reliable (Cronbach's alpha = 0.936). There was no response bias in the scale (Hotelling's T2 = 433.558, p < .001) and it was additive (Tukey's Non-additivity = 0.000, p < .001). The PESSS is a 20-item scale measuring excessive social support between 1 and 6 weeks postpartum. The PESSS serves as a guiding tool for health care professionals to identify excessive environmental pressure hindering mothers' maternal role and to provide care accordingly. In this context, health care professionals can readily utilize the PESSS in routine postpartum assessments for mothers.

Three-Direction Fusion for Accurate Volumetric Liver and Tumor Segmentation.

Biomedical image segmentation of organs, tissues and lesions has gained increasing attention in clinical treatment planning and navigation, which involves the exploration of two-dimensional (2D) and three-dimensional (3D) contexts in the biomedical image. Compared to 2D methods, 3D methods pay more attention to inter-slice correlations, which offer additional spatial information for image segmentation. An organ or tumor has a 3D structure that can be observed from three directions. Previous studies focus only on the vertical axis, limiting the understanding of the relationship between a tumor and its surrounding tissues. Important information can also be obtained from sagittal and coronal axes. Therefore, spatial information of organs and tumors can be obtained from three directions, i.e. the sagittal, coronal and vertical axes, to understand better the invasion depth of tumor and its relationship with the surrounding tissues. Moreover, the edges of organs and tumors in biomedical image may be blurred. To address these problems, we propose a three-direction fusion volumetric segmentation (TFVS) model for segmenting 3D biomedical images from three perspectives in sagittal, coronal and transverse planes, respectively. We use the dataset of the liver task provided by the Medical Segmentation Decathlon challenge to train our model. The TFVS method demonstrates a competitive performance on the 3D-IRCADB dataset. In addition, the t-test and Wilcoxon signed-rank test are also performed to show the statistical significance of the improvement by the proposed method as compared with the baseline methods. The proposed method is expected to be beneficial in guiding and facilitating clinical diagnosis and treatment.

Biliary Duct Dilatation: AJR Expert Panel Narrative Review.

Biliary duct dilatation is a common incidental finding in practice, but it is unlikely to indicate biliary obstruction in the absence of clinical symptoms or elevated levels on liver function tests (LFTs). However, the clinical presentation may be nonspecific, and LFTs may either be unavailable or difficult to interpret. The goal of this AJR Expert Panel Narrative Review is to highlight a series of topics fundamental to the management of biliary duct dilatation, providing consensus recommendations in a question-and-answer format. We start by covering a basic approach to interpreting LFT results, the strengths and weaknesses of the biliary imaging modalities, and how and where to measure the extrahepatic bile duct. Next, we define the criteria for biliary duct dilatation, including patients with prior cholecystectomy and advanced age, and discuss when and whether biliary duct dilatation can be attributed to papillary stenosis or sphincter of Oddi dysfunction. Subsequently, we discuss two conditions in which the duct is pathologically dilated but not obstructed: congenital cystic dilatation (i.e., choledochal cyst) and intraductal papillary neoplasm of the bile duct. Finally, we provide guidance regarding when to recommend obtaining additional imaging or testing, such as endoscopic ultrasound or ERCP, and include a discussion of future directions in biliary imaging.

Comprehensive Genomic Testing: Tissue Stewardship and Best Practices

Biomarker-driven targeted therapies have shaped the oncology treatment landscape for patients with advanced solid tumors over the past decade. Comprehensive genomic profiling (CGP) has played a key role in precision medicine as it enables simultaneous identification of multiple biomarkers to guide cancer diagnosis, therapy selection, and prognostication. As a result, tissue stewardship for successful CGP testing is paramount. In addition, widespread adoption of less invasive sampling techniques leaves less diagnostic tissue for additional or future testing as smaller biopsies are acquired. To help oncology care practitioners overcome these challenges, this paper provides an overview of current genomic testing methodologies and offers guidelines on best practices for tissue stewardship and preanalytic practices for successful CGP testing and efficient turnaround times for laboratory tests.

Dicationic imidazole ionic liquid stationary phase for preservative detection and its application under mixed mode of HILIC/RPLC/IEC

Food safety has always been a great concern, and the detection of additives is vital to ensuring food safety. Therefore, there is a necessity to develop a method that can quickly and efficiently separate and detect additives in food. High performance liquid chromatography is widely used in the analysis and testing of food additives. Ionic liquids have attracted wide attention in the preparation of high performance liquid chromatography stationary phases owing to their high stability, low vapor pressure and adjustable structure. We developed a novel dicationic imidazole ionic liquid stationary phase for the simultaneous determination of organic preservatives (sodium benzoate, potassium sorbate) and inorganic preservatives (nitrate and nitrite) in foodstuffs under mixed-mode chromatography. The method had the advantages of easy operation, high reproducibility, good linearity and precision. In the detection of these four preservatives, the limit of detection ≤0.4740mg⋅L-1 and the limit of quantification ≤1.5800mg⋅L-1. The intra-day and inter-day precision were less than 4.02%, and the recovery rate was 95.90∼100.19 %. At the same time, we also characterized the stationary phase, explored the mechanism and evaluated the chromatographic performance. The stationary phase was able to operate under the mixed mode of reversed phase/hydrophilic interaction/ion exchange chromatography, and it was capable of separating hydrophilic substances, hydrophobic substances, acids, and inorganic anionic substances with good separation efficiency and had high column efficiency. In summary, the stationary phase has a promising application in the routine analysis of organic and inorganic preservatives in food. In addition, the stationary phase has good separation ability for hydrophilic, hydrophobic, ionic substances and complex samples, making it a prospective material for chromatographic separation.

Barium titanate write-once read-many times resistive memory with an ultra-high on/off current ratio of 108

Barium titanate write-once read-many times resistive memory with an ultra-high on/off current ratio of 108

The Role of Surveillance in Predicting Fracture in Pediatric Patients With Incidentally Discovered Nonossifying Fibromas and Fibrous Cortical Defects: Is It Worth It?

Nonossifying fibroma (NOF) and fibrous cortical defect (FCDs), the most common benign pediatric bone lesions, are usually incidental x-ray findings. Surveillance of characteristic lesions has been recommended to monitor for enlargement and assess fracture risk. However, no accepted fracture risk prediction guidelines exist, so indications for prophylactic surgery are unclear. The study's purposes were to (1) characterize the timing of NOF/FCD-associated fractures, (2) quantify the resources devoted to surveillance, and (3) evaluate the potential for surveillance to prevent pathologic fracture. A single institution retrospective review was conducted to identify pediatric patients (below 18y old) with clinical-radiographic documentation of an NOF or FCD diagnosis from 2012 to 2020. Patients who presented with fracture were tallied but excluded from the surveillance analysis. Patients without at least one follow-up visit were also excluded. Lesional radiographic features were characterized on initial imaging. The number of visits and imaging studies devoted to surveillance were tabulated. The number of fractures and prophylactic surgeries were recorded to quantify the potential of surveillance to prevent pathologic fractures. The study population presenting without fracture consisted of 301 patients with 364 lesions with a mean follow-up of 20 months. By contrast, over the same period, 38 patients presented with NOF/FCD associated pathologic fractures. Surveillance included 1037 additional imaging tests over 1311 follow-up visits, or on average, 3.4 imaging studies and 4.4 visits per patient. During surveillance, only 2 (0.55%) lesions fractured. Another 10/364 (2.8%) patients underwent curettage and grafting, suggesting that-at best-the potential for preventing pathologic fracture by surveillance, assuming all 10 patients who underwent surgery would have subsequently fractured along with the 2 documented fractures, is 3.3% of lesions (12/364). The small number of fractures and surgeries during the follow-up period probably does not justify additional resources for surveillance beyond the initial visit, except in symptomatic patients with large lesions. However, subsequent visits may play a role in educating patients and their families regarding the natural history of these lesions. Prognostic Level II-retrospective study.

Modes of assay interference and the effectiveness of serum pretreatment approaches in detection of anti-HLA antibodies

AimsSeveral modes of assay interference common to immunoassays affect solid-phase single-antigen bead-based immunoassays (SAB) used to detect antibodies against human leucocyte antigens (HLA). Best practice recommendations include methods to address...

Analysis of Planetary Scale Waves Using Idealized Sudden Stratospheric Warming Simulations in Different Dynamical Cores

AbstractPlanetary waves from the troposphere are known to play an important role in sudden stratospheric warming (SSW). To evaluate the representation of large‐scale waves in idealized SSW simulations, three dynamical cores of the National Center for Atmospheric Research Community Atmosphere Model were tested in this study: the Eulerian (EUL) spectral‐transform, finite‐volume (FV), and spectral element (SE) models. Notable differences were observed among the dynamical cores, with FV being unable to generate major SSWs and simulating minor SSWs less effectively than the other models. Wave decomposition analysis revealed distinct planetary wave propagation patterns during the development of each event. Zonal Wave Number 2 wave activities primarily determined SSW types, and ZWN1 led SSWs to recovery during the ensuing periods. However, FV failed to adequately propagate large‐scale waves in minor SSW events, preventing the reversal of stratospheric zonal‐mean zonal winds. Interestingly, FV showed decreased upward Eliassen–Palm flux compared to that of other dynamical cores, even during climatology. Additional tests were performed to examine the reasons for FV's atypical results, but the dynamic impacts on planetary waves remain poorly understood.

Classification of optical coherence tomography images using deep machine learning methods

Backgraund. Optical coherence tomography (OCT) is a modern high-tech and informative method for detecting pathology of the retina and preretinal layers of the vitreous body. However, the description and interpretation of the research results require high qualifications and special training of an ophthalmologist, and significant time expenditure for the doctor and the patient. At the same time, the use of mathematical models based on artificial neural networks (ANN- models) currently makes it possible to automate many processes associated with image processing. Therefore, solving problems associated with automating the process of classifying OCT images based on ANN models is actual.&#x0D; Aims. To develop architectures of mathematical (computer) models based on deep learning of convolutional neural networks (CNN) for classification of OCT images of the retina. To compare the results of computational experiments conducted using Python tools in the Google Colaboratory with single-model and multi-model approaches and evaluate classification accuracy. To make conclusions about the optimal architecture of ANN models and the values of the hyperparameters used.&#x0D; Materials and methods. The original dataset, which was anonymized OCT images of real patients, included more than 2000 images obtained directly from the device in a resolution of 1920 × 969 × 24 BPP. The number of image classes is 12. To create the training and validation data sets, a subject area of 1100 × 550 × 24 BPP was “cut out.” Various approaches were studied: the possibility of using pretrained CNNs with transfer learning, techniques for resizing and augmenting images, as well as various combinations of hyperparameters of ANN-models. When compiling the model, the following parameters were used: Adam optimizer, categorical_crossentropy loss function, accuracy metric. All technological processes with images and ANN-models were carried out using Python language tools in Google Colaboratory.&#x0D; Results. Single-model and multi-model principles for classifying OCT images of the retina are proposed. Computational experiments on automated classification of such images obtained from a DRI OCT Triton 3D tomograph using various ANN model architectures showed an accuracy of 98-100% during training and validation and 85% during an additional test, which is a satisfactory result. The optimal architecture of the ANN model - a six-layer convolutional network - was selected and the values of its hyperparameters were determined.&#x0D; Conclusions. The results of deep training of convolutional neural network models with various architectures, their validation and testing showed satisfactory classification accuracy of retinal OCT images. These developments can be used in decision support systems in the field of ophthalmology.

Evaluating different rates of activated carbon in commercially produced seed coatings in laboratory and field trials

Pre‐emergent herbicides, commonly employed for managing invasive annual plants, often fail to meet restoration targets due to the absence of remnant perennial plants, which leaves sites vulnerable to re‐invasion and hinders effective control of annual grasses. Combining an herbicide treatment with seeding is therefore desirable, but seeded plants can also be negatively impacted by pre‐emergent herbicides. Herbicide protection (HP) seed technologies use activated carbon to adsorb herbicide near seeds and have shown promise for allowing simultaneous deployment of herbicide and seed, but recent research recommends numerous additional refinements be tested. We addressed some of these recommendations through one laboratory and a field trial replicated at multiple sites to explore whether commercially produced, single‐seed HP coatings with two different rates of activated carbon can prevent herbicide‐related damage to two perennial bunchgrasses native to the western United States. We also investigated how these coated prototypes compare in performance to the multi‐seed extruded herbicide protection pellets (HPPs) tested in prior research. In the laboratory, neither coating treatment reduced total emergence, emergence rate, survival, or biomass in the absence of herbicide. In the presence of herbicide, both provided several‐fold higher survival and aboveground biomass compared to untreated bare seed, but this represented incomplete protection from herbicide. In field trials where conditions were harsher than the laboratory, we found no evidence of HP from any treatment, and HPPs reduced seedling count for one species. We conclude that the tested HP coating prototype is an improvement over HPPs but requires additional refinements and testing.

Potential Nephrotoxicity of Combination of Vancomycin and Piperacillin-Tazobactam: Recommendations from the AG ABS of the DGPI supported by experts of the GPN

The combination of vancomycin and piperacillin/tazobactam (V+P/T) is used for empirical antibiotic treatment of severe infections, especially in immunocompromised patients and those colonized with multidrug-resistant bacteria. Nephrotoxicity is a frequently observed adverse effect of vancomycin. Its risk can be reduced by therapeutic drug monitoring and adjusted dosing. Piperacillin/tazobactam (P/T) rarely causes interstitial nephritis. The results of retrospective cohort studies in children predominantly show a low, clinically irrelevant, additive nephrotoxicity (defined as an increase in creatinine in the serum) of both substances. Due to the limitations of the existing publications, the ABS working group of the DGPI and experts of the GPN do not recommend against the use of P/T plus vancomycin. Preclinical studies and a prospective study with adult patients, which evaluated different renal function tests as well as clinical outcomes, do not support previous findings of additive nephrotoxicity. Time-restricted use of V+P/T can minimize exposure and the potential risk of nephrotoxicity. Local guidelines, developed in collaboration with the antibiotic stewardship team, should define the indications for empirical and targeted use of P/T and V+P/T. When using combination therapy with V+P/T, kidney function should be monitored through clinical parameters (volume status, balancing, blood pressure) as well as additional laboratory tests such as serum creatinine and cystatin C.

Interconnect Stress Testing as a Tool for Assessment of Reliability of Modern PCBs

The of miniaturization can be seen in electronics for some time already. The pinout of active components grows enabling them to have additional functions. The trend in usage of System in a Package (SiP) solutions is also evident thus routing of the active and passive elements became also challenging. To overcome this challenge boards with High Density Interconnection (HDI) where not only through hole, but also different kinds of microvias e.g. blind, buried, stacked, staggered via are used. The standard procedure to test reliability of boards and assemblies is very resource-hungry especially in time and money, as the tests have to be carried out in climatic chambers which lasts for weeks, followed by additional destructive testing like cross-sections. On the other hand IST (Interconnect Stress Testing) is a quick test, that enables to have assessment of the used technology especially the quality of the through holes of all types. Although the coupons are destroyed during the test, it is not necessary to test the manufactured circuits. This saves both materials and time. The technology optimizations and the key findings will be presented within the paper.