Impact of temperature and relative humidity variations on coda waves in concrete.

The microstructure of concrete can be affected by many factors, from non-destructive environmental factors through to destructive damage induced by transient stresses. Coda wave interferometry is a technique that is sensitive enough to detect weak changes within concrete by evaluating the ultrasonic signal perturbation compared to a reference state. As concrete microstructure is sensitive to many factors, it is important to separate their contributions to the observables. In this study, we characterize the relationships between the concrete elastic and inelastic properties, and temperature and relative humidity. We confirm previous theoretical studies that found a linear relationship between temperature changes and velocity variation of the ultrasonic waves for a given concrete mix, and provide scaling factors per Kelvin for multiple settings. We also confirm an anti-correlation with relative humidity using long-term conditioning. Furthermore, we explore beyond the existing studies to establish the relationship linking humidity and temperature changes to ultrasonic wave attenuation.

Evaluation of compressive damage in concrete using ultrasonic nonlinear coda wave interferometry.

This study investigates the feasibility of nonlinear coda wave interferometry (NCWI) for evaluating compressive damage in concrete, with a particular focus on the interference caused by the compressive stress-induced slow dynamics. Slow dynamics refers to a phenomenon in which the stiffness of concrete immediately decreases after moderate mechanical conditioning and then logarithmically evolves back to its initial value over time. A series of experiments were conducted to validate this concept. The experimental findings indicate that slow dynamics following the unloading of concrete specimen significantly interfere with NCWI testing. The changes in dv/v caused by the slow dynamics are opposite to those induced by the pump wave in NCWI. After the slow dynamics have been eliminated, an evaluation indicator, defined as the efficient nonlinear level αdv/v, demonstrates an excellent correlation with compressive damage. The value of the indicator decreases with increasing compressive stress. Furthermore, the coda wave interferometry (CWI) and direct wave interferometry (DWI) are performed as comparisons. In summary, the feasibility and superiority of NCWI are demonstrated in concrete compressive damage evaluation.

Testing a Context-Enriched Model of Successful Aging in Multiple Large Data Infrastructures with Individuals in Advanced Old Age.

BACKGROUND AND OBJECTIVES: Few people who are ages 80+ meet the criteria of successful aging (SA) proposed by Rowe and Kahn. Going beyond the individual-level conceptualization, we argue that SA always operates in multiple contexts and that context may become most critical in advanced old age. However, we are not aware of any previous study providing an empirical test of how contexts for SA unfold across persons 80 years and older, including those living in institutions. RESEARCH DESIGN AND METHODS: We estimated and compared prevalences of successful aging based on a classic versus context-enriched understanding of SA in multiple large surveys of older adults, i.e., the D80+ study (N = 3.233) and the NRW80+ study (N [baseline] = 1.863). In addition to replication across independent samples, we investigated the stability of context-related SA across time. RESULTS: Prevalences of SA according to Rowe and Kahn were 9.1% in adults aged 80-84 and 0.7% in persons 90 years or older. However, prevalence rates for those with good contexts at their disposal even if not fulfilling Rowe and Kahn's criteria were much higher across all age groups (80-84 years: 54.9%, 90 years and older: 44.4%). Greater two-year stability was observed for contextual compared to individual criteria. Notably, positive effects of context on SA were stronger at onset compared to late fourth age. DISCUSSION AND IMPLICATIONS: Our findings support a contextualized understanding of SA and inform policy that furthering SA in the fourth age requires the optimization of multiple contexts at the community level.

Losing sleep influences dietary intake in children: a longitudinal compositional analysis of a randomised crossover trial.

BACKGROUND: Although inadequate sleep increases the risk of obesity in children, the mechanisms remain unclear. The aims of this study were to assess how sleep loss influenced dietary intake in children while accounting for corresponding changes in sedentary time and physical activity; and to investigate how changes in time use related to dietary intake. METHODS: A randomized crossover trial in 105 healthy children (8-12 years) with normal sleep (~ 8-11 h/night) compared sleep extension (asked to turn lights off one hour earlier than usual for one week) and sleep restriction (turn lights off one hour later) conditions, separated by a washout week. 24-h time-use behaviors (sleep, wake after sleep onset, physical activity, sedentary time) were assessed using waist-worn actigraphy and dietary intake using two multiple-pass diet recalls during each intervention week. Longitudinal compositional analysis was undertaken with mixed effects regression models using isometric log ratios of time use variables as exposures and dietary variables as outcomes, and participant as a random effect. RESULTS: Eighty three children (10.2 years, 53% female, 62% healthy weight) had 47.9 (SD 30.1) minutes less sleep during the restriction week but were also awake for 8.5 (21.4) minutes less at night. They spent this extra time awake in the day being more sedentary (+ 31 min) and more active (+ 21 min light physical activity, + 4 min MVPA). After adjusting for all changes in 24-h time use, losing 48 min of sleep was associated with consuming significantly more energy (262 kJ, 95% CI:55,470), all of which was from non-core foods (314 kJ; 43, 638). Increases in sedentary time were related to increased energy intake from non-core foods (177 kJ; 25, 329) whereas increases in MVPA were associated with higher intake from core foods (72 kJ; 7,136). Changes in diet were greater in female participants. CONCLUSION: Loss of sleep was associated with increased energy intake, especially of non-core foods, independent of changes in sedentary time and physical activity. Interventions focusing on improving sleep may be beneficial for improving dietary intake and weight status in children. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ANZCTR ACTRN12618001671257, Registered 10th Oct 2018, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367587&isReview=true.

Using isometric log-ratio in compositional data analysis for developing a groundwater pollution index.

This study introduces a novel groundwater pollution index (GPI) formulated through compositional data analysis (CoDa) and robust principal component analysis (RPCA) to enhance groundwater quality assessment. Using groundwater quality monitoring data from sites impacted by the 2010-2011 foot-and-mouth disease outbreak in South Korea, CoDa uncovers critical hydrochemical differences between leachate-influenced and background groundwater. The GPI was developed by selecting key subcompositional parts (NH4+-N, Cl-, and NO3--N) using RPCA, performing the isometric log-ratio (ILR) transformation, and normalizing the results to environmental standards, thereby providing a more precise and accurate assessment of pollution. Validated against government criteria, the GPI has shown its potential as an alternative assessment tool, with its reliability confirmed by receiver operating characteristic curve analysis. This study highlights the essential role of CoDa, especially the ILR -transformation, in overcoming the limitations of traditional statistical methods that often neglect the relative nature of hydrochemical data. Our results emphasize the utility of the GPI in significantly advancing groundwater quality monitoring and management by addressing a methodological gap in the quantitative assessment of groundwater pollution.

Average grain size evaluation using scattering-induced attenuation of coda waves.

Grain size is one of the key microstructural factors affecting the mechanical properties of polycrystalline metal materials. In this study, a novel method for grain size evaluation using ultrasonic coda waves is proposed. Different from conventional bulk wave methods that require a point-by-point scanning of the structure, the proposed method allows for a rapid evaluation of the average grain size of the whole part from a single inspection location using one-pass testing data. A piecewise energy attenuation function dealing with different attenuation mechanisms is proposed to obtain the effective attenuation coefficient of coda waves. A power-law model is constructed to correlate the effective attenuation coefficient with the average grain size. Ultrasonic testing on nickel-based superalloy plate specimens with different average grain sizes is performed for model calibration and method verification. The applicability and robustness of the proposed method are further validated using a realistic turbine disk specimen with an irregular shape and non-uniform grain sizes. Results show that the proposed method yields a reliable and accurate estimation of the average grain size with a maximum relative error less than 20 %.

Combinatorial Quantification of Multi-Features of Coda Waves in Temperature-Affected Concrete Beams.

Coda waves are highly sensitive to changes in medium properties and can serve as a tool for structural health monitoring (SHM). However, high sensitivity also makes them susceptible to noise, leading to excessive dispersion of monitoring results. In this paper, a coda wave multi-feature extraction method is proposed, in which three parameters, the time shift, the time stretch, and the amplitude variation of the wave trains within the time window, are totally derived. These three parameters are each mapped to the temperature variations of concrete beams, and then combined together with their optimal weight coefficients to give a best-fitted temperature-multi-parameter relationship that has the smallest errors. Coda wave signals were collected from an ultrasonic experiment on concrete beams within an environmental temperature range of 14 °C~21 °C to verify the effectiveness of the proposed method. The results indicate that the combination of multi-features derived from coda wave signals to quantify the medium temperature is feasible. Compared to the relationship established by a single parameter, the goodness-of-fit is improved. During identification, the method effectively reduces the dispersion of identification errors and mitigates the impact of noise interference on structural state assessment. Both the identification accuracy and stability are improved by more than 50%, and the order of magnitude of the identification accuracy is improved from 1 °C to 0.1 °C.

A nose for trouble: ecotoxicological implications for climate change and disease in Saiga antelope (S. t. tatarica).

In recent decades, Saiga antelope (Saiga t. tatarica) mass die-offs have become more common. The mass die-off of 2015 in central Kazakhstan, recorded 140,000 individual deaths across multiple herds. Previously, research has shown atmospheric humidity, the bacterium Pasteurella multocida serotype B, and resultant haemorrhagic septicaemia, were the primary cause. However, other synergistic factors may have impacted this process. Here we use a multivariate compositional data analysis (CoDA) approach to assess what other factors may have been involved. We show a pollutant linkage mechanism where relative humidity and dewpoint temperature combine with environmental pollutants, potentially toxic elements (e.g., Hg, As), complex carbon compounds (e.g., Acetone, Toluene), and inorganic compounds (e.g., CHx, SO2) which affected the Saiga during the calving season (start and peak) and at the onset of the mass die-off. We suggest a mechanism for this process. Upon arrival at their carving grounds, the Saiga experienced a sudden precipitation event, a spike in temperatures, and resultant high humidity occurs. The infectious bacterium P. multocida serotype B then spreads. Further, environmental pollutants contained within steppe soils are released to the air, forming localised smog events, these synergistically combine, and mass die-off occurs.

Compositional associations between movement-related behaviours and functional outcomes post-stroke.

PURPOSE: To examine the associations between the composition of movement-related behaviours (sedentary behaviour, sleep, standing, and stepping) and functional outcomes post-stroke. METHODS: This study included 34 adults with stroke (mean age: 64.6 ± 12.5 years; time since stroke: 3.5 ± 1.1 months) who underwent an 8-week sedentary behaviour intervention. Functional outcomes were assessed using the timed up and go (TUG) and gait speed tests. Compositional data analysis was used to investigate the relationships between movement-related behaviours and functional outcomes. RESULTS: The baseline composition of movement-related behaviours showed significant associations with changes in TUG (F = 4.28, p = 0.01) and gait speed (F = 4.63, p = 0.01) after the 8-week reducing sedentary behaviour intervention. Reallocating ≥ 30 min/day to stepping, while proportionally decreasing other movement-related behaviours, was associated with a significant change in TUG. Similarly, a relative reallocation of ≥ 40 min/day to stepping was associated with a clinically meaningful change in gait speed. CONCLUSIONS: This study highlights the importance of considering movement-related behaviours in relation to functional outcomes post-stroke. Reallocating at least 30 min per day to stepping, relative to a reduction in other movement-related behaviours, is associated with significant and meaningful change in functional outcomes.

Reallocating at least 30 minutes/day to stepping, relative to a decrease in other movement-related behaviours, is associated with a positive change in functional mobility after an 8-week post-stroke sedentary behaviour intervention.Relative to a decrease in other movement-behaviours, reallocating ≥ 40 minutes/day to stepping is associated with a meaningful change in gait speed.Reallocating time to standing or sleep at the expense of other movement behaviours is not associated with better functional mobility or gait speed.Finding the optimal balance in movement-related behaviours that favours more stepping may lead to improvements in both functional mobility and gait speed.

Use of pointing in parent-child interactions by hearing children of deaf and hearing parents: A follow-up from 1- to 3-years of age.

Pointing plays a significant role in communication and language development. However, in spoken languages pointing has been viewed as a non-verbal gesture, whereas in sign languages, pointing is regarded to represent a linguistic unit of language. This study compared the use of pointing between seven bilingual hearing children of deaf parents (Kids of Deaf Adults [KODAs]) interacting with their deaf parents and five hearing children interacting with their hearing parents. Data were collected in 6-month intervals from the age of 1;0 to 3;0. Pointing frequency among the deaf parents and KODAs was significantly higher than among the hearing parents and their children. In signing dyads pointing frequency remained stable, whereas in spoken dyads it decreased during the follow-up. These findings suggested that pointing is a fundamental element of parent-child interaction, regardless of the language, but is guided by the modality, gestural and linguistic features of the language in question.

Static and dynamic diffuse wave inspection of delaminations in carbon fiber reinforced composites.

This paper aims to realize a self-reference delamination inspection in CFRPs with diffuse ultrasonic waves. The static experiments are first conducted on samples with a machined defect of 0.5 mm in height which simulates an opening state delamination. The diffusivity decreases with delamination diameter (pristine, 6 mm, 12 mm) at a constant depth and increases with delamination depth (0.25 mm, 0.75 mm) at a given diameter. However, no clear pattern can be found for the dissipation coefficient because of the intrinsic absorption and manufacturing uncertainties. Both coefficients are insensitive to the delamination height under loading. In contrast, the corresponding maximum cross-correlation coefficient from coda wave interferometry shows a variation of 2.4-7 % in different samples. A sharp transition can be found due to the clapping effect when the delamination is fully closed. After then, the static loading is replaced by acoustic stressing pulse from PZT in a closed delamination sample. The low frequency pulse induced reverberation field is sampled by a high frequency diffuse wave semi-synchronously, which mimics a cyclic and low amplitude loading during service. All the dynamic cross-correlation coefficient curves present an ascending trend during voltage ramp-up due to the viscoelastic effect, no matter in the intact zone or delamination zone. When the voltage threshold of 250 V is reached, the clapping effect can be triggered. A descending trend has been found not only when the excitation is right above but also near the delamination. This can be applied as an indicator of the delamination existence regionally without scanning. Such nonlinear measurement system can be expanded to passive imaging and other deficiency inspection in CFRPs with less demanding facilities.

Processing of English Coda Laterals in L2 Listeners: An Eye-Tracking Study.

This study explores speech processing of English coda laterals (dark L's) in second language (L2) listeners whose native language does not permit laterals at syllable coda positions. We tested L2 listeners' (native Mandarin) perception of coda laterals following three Australian English vowels differing in phonological backness, including /iː/, /ʉː/, and /oː/, which represent a front vowel, and central vowel, and a back vowel, respectively. L2 listeners first completed an AX task which tested their ability to discriminate between /iː/-/iːl/, /ʉː/-/ʉːl/, and /oː/-/oːl/, and then they completed an identification task with eye-tracking which tested their ability to distinguish vowel-lateral sequences and bare vowel categories using explicit phonological-orthographical labels. The results show that vowel backness plays a key role in L2 listeners' perceptual accuracy of English coda laterals, whereas the eye-tracking and identification data suggest some paradigmatic differences between the two tasks. Mandarin listeners show excellent discrimination and identification of coda laterals following a front vowel and poor performance following a back vowel, whereas the central vowel has led to intermediate patterns.

A perception-induced /t/-to-/k/ sound change: evidence from a cross-linguistic study.

John Ohala claimed that the source of sound change may lie in misperceptions which can be replicated in the laboratory. We tested this claim for a historical change of /t/ to /k/ in the coda in the Southern Min dialect of Chaoshan. We conducted a forced-choice segment identification task with CVC syllables in which the final C varied across the segments [p t k ʔ] in addition to a number of further variables, including the V, which ranged across [i u a]. The results from three groups of participants whose native languages have the coda systems /p t k ʔ/ (Zhangquan), /p k ʔ/ (Chaoshan) and /p t k/ (Dutch) indicate that [t] is the least stably perceived segment overall. It is particularly disfavoured when it follows [a], where there is a bias towards [k]. We argue that this finding supports a perceptual account of the historically documented scenario whereby a change from /at/ to /ak/ preceded and triggered a more general merger of /t/ with /k/ in the coda of Chaoshan. While we grant that perceptual sound changes are not the only or even the most common type of sound change, the fact that the perception results are essentially the same across the three language groups lends credibility to Ohala's perceptually motivated sound changes.

Combination of UHPLC-MS/MS with context-specific network and cheminformatic approaches for identifying bioactivities and active components of propolis.

Discovering new bioactivities and identifying active compounds of food materials are major fields of study in food science. However, the process commonly requires extensive experiments and can be technically challenging. In the current study, we employed network biology and cheminformatic approaches to predict new target diseases, active components, and related molecular mechanisms of propolis. Applying UHPLC-MS/MS analysis results of propolis to Context-Oriented Directed Associations (CODA) and Combination-Oriented Natural Product Database with Unified Terminology (COCONUT) systems indicated atopic dermatitis as a novel target disease. Experimental validation using cell- and human tissue-based models confirmed the therapeutic potential of propolis against atopic dermatitis. Moreover, we were able to find the major contributing compounds as well as their combinatorial effects responsible for the bioactivity of propolis. The CODA/COCONUT system also provided compound-associated genes explaining the underlying molecular mechanism of propolis. These results highlight the potential use of big data-driven network biological approaches to aid in analyzing the impact of food constituents at a systematic level.

Diverticular Inflammation and Complication Assessment classification, CODA score and fecal calprotectin in clinical assessment of patients with diverticular disease: A decision curve analysis.

BACKGROUND AND AIMS: The Diverticular Inflammation and Complication Assessment (DICA) classification and the Combined Overview on Diverticular Assessment (CODA) were found to be effective in predicting the outcomes of Diverticular Disease (DD). We ascertain whether fecal calprotectin (FC) can further aid in improving risk stratification. METHODS: A three-year international, multicentre, prospective cohort study was conducted involving 43 Gastroenterology and Endoscopy centres. Survival methods for censored observations were used to estimate the risk of acute diverticulitis (AD) in newly diagnosed DD patients according to basal FC, DICA, and CODA. The net benefit of management strategies based on DICA, CODA and FC in addition to CODA was assessed with decision curve analysis, which incorporates the harms and benefits of using a prognostic model for clinical decisions. RESULTS: At the first diagnosis of diverticulosis/DD, 871 participants underwent FC measurement. FC was associated with the risk of AD at 3 years (HR per each base 10 logarithm increase: 3.29; 95% confidence interval, 2.13-5.10) and showed moderate discrimination (c-statistic: 0.685; 0.614-0.756). DICA and CODA were more accurate predictors of AD than FC. However, FC showed high discrimination capacity to predict AD at 3 months, which was not maintained at longer follow-up times. The decision curve analysis comparing the combination of FC and CODA with CODA alone did not clearly indicate a larger net benefit of one strategy over the other. CONCLUSIONS: FC measurement could be used as a complementary tool to assess the immediate risk of AD. In all other cases, treatment strategies based on the CODA score alone should be recommended.

Written products and writing processes in Swedish deaf and hard of hearing children: an explorative study on the impact of linguistic background.

The small body of research on writing and writing processes in the group of deaf and hard of hearing (DHH) children has shown that this group struggles more with writing than their hearing peers. This article aims to explore in what ways the DHH group differs from their peers regarding the written product and the writing processes. Participants are all in the age span 10-12 years old and include: (a) 12 DHH children with knowledge of Swedish sign language (Svenskt teckenspråk, STS) as well as spoken Swedish, (b) 10 age-matched hearing children of deaf adults (CODA) who know STS, (c) 14 age-matched hearing peers with no STS knowledge. More specifically we investigate how text length and lexical properties relate to writing processes such as planning (measured through pauses) and revision, and how the background factors of age, gender, hearing and knowledge of STS predict the outcome in product and process. The data consists of picture-elicited narratives collected with keystroke logging. The overall results show that age is a strong predictor for writing fluency, longer texts and more sophisticated lexicon for all the children. This confirms theories on writing development which stress that when children have automatized basic low-level processes such as transcription and spelling, this will free up cognitive space for engaging in high-level processes, such as planning and revision-which in turn will result in more mature texts. What characterizes the DHH group is slower writing fluency, higher lexical density, due to omitted function words, and extensive revisions (both deletions and insertions) on word level and below. One explanation for the last finding is that limitations in the auditory input lead to more uncertainty regarding correct and appropriate lexical choices, as well as spelling. The article contributes with more specific knowledge on what is challenging during writing for DHH children with knowledge of STS and spoken Swedish in middle school, in the developmental stage when basic writing skills are established.

Oral intake of Lactiplantibacillus pentosus LPG1 Produces a Beneficial Regulation of Gut Microbiota in Healthy Persons: A Randomised, Placebo-Controlled, Single-Blind Trial.

The search for vegetable-origin probiotic microorganisms is a recent area of interest. This study conducted a phase I clinical trial to assess the effects of oral administration of Lactiplantibacillus pentosus LPG1, a natural strain with probiotic potential isolated from table olive fermentations, on the gut microbiota. The trial was a randomised, placebo-controlled, single-blind study involving 39 healthy volunteers. Group A (n = 20) ingested one capsule/day of L. pentosus LPG1 containing 1 × 1010 UFC/capsule, while Group B (n = 19) received one capsule/day containing only dextrose (placebo). The capsules were taken during breakfast for 30 consecutive days. Human stool samples were collected from all volunteers at the beginning (baseline) and at the end of the study (post-intervention) and were subjected to 16S rRNA metataxonomic analysis using Illumina MiSeq. Sequencing data at the genus level were statistically analysed using traditional methods and compositional data analysis (CoDA). After treatment, the alpha diversity in Group B (placebo) decreased according to an increase in the Berger and Parker dominance index (p-value < 0.05); moreover, dominance D increased and Simpson 1-D index decreased (p-value < 0.10). The Lactobacillus genus in the faeces was included in the CoDA signature balances (selbal and coda4microbiome) and played a notable role in distinguishing samples from baseline and post-intervention in Group A (LPG1). Additionally, ingesting L. pentosus LPG1 modified the gut microbiota post-intervention, increasing the presence of Parabacteroides and Agathobacter, but reducing Prevotella. These findings suggest that L. pentosus LPG1 is a potentially beneficial gut microbiota modulator in healthy persons.

Towards quantifying the effect of pump wave amplitude on cracks in the Nonlinear Coda Wave Interferometry method.

In Non-Destructive Testing and Evaluation (NDT&E), an ultrasonic method called Nonlinear Coda Wave Interferometry (NCWI) has recently been developed to detect cracks in heterogeneous materials such as concrete. The underlying principle of NCWI is that a pump wave is used to activate the crack breathing which interact with the source probe signal. The resulting signal is then measured at receiver probes. In this work, a static finite element model (FEM) is used to simulate the pump wave/crack interaction in order to quantifies the average effect of the pump waves on a crack. By considering both crack opening and closure phases during the dynamic pump wave excitation, this static model aims to determine the pump stress amplitude for a given relative crack length variation due to the dynamic pump wave excitation at different amplitudes. Numerical results show, after reaching certain stress amplitude, a linear relationship between the relative crack length variation and the equivalent static load when considering a partially closed crack at its tips. Then, numerical NCWI outputs, e.g., the relative velocity change θ and the decorrelation coefficient Kd, have been calculated using a spectral element model (SEM). These results agree with previously published experimental NCWI results derived for a slightly damaged 2D glass plate.

Complex thinking and social entrepreneurship. An approach from the methodology of compositional data analysis.

This article describes a study that sought to identify the correlation between social entrepreneurship and complex thinking competencies in a population of Mexican students. The article uses the novel approach of compositional data analysis. Compositional data analysis focuses on studying data that are part of a whole, whose importance lies in the relative information between its parts and not in absolute values. The analysis allows us to identify an association between the competencies and find statistically significant relationships between sub-competencies. In particular, correlations can be seen between the sub-competencies of scientific thinking and critical thinking with the sub-competency of self-control, leadership, and social awareness and social value. Furthermore, a correlation is observed between systemic thinking with the sub-competency of social awareness and social value, self-control, and leadership sub-competencies. In a practical way, this article introduces the compositional data analysis methodology to the academic educational literature focused on the study and measurement of competencies, opening possibilities for more precise, broad, descriptive analyses not achieved with other methodologies.

Tissue clearing and 3D reconstruction of digitized, serially sectioned slides provide novel insights into pancreatic cancer.

Pancreatic cancer is currently the third leading cause of cancer death in the United States. The clinical hallmarks of this disease include abdominal pain that radiates to the back, the presence of a hypoenhancing intrapancreatic lesion on imaging, and widespread liver metastases. Technologies such as tissue clearing and three-dimensional (3D) reconstruction of digitized serially sectioned hematoxylin and eosin-stained slides can be used to visualize large (up to 2- to 3-centimeter cube) tissues at cellular resolution. When applied to human pancreatic cancers, these 3D visualization techniques have provided novel insights into the basis of a number of the clinical characteristics of this disease. Here, we describe the clinical features of pancreatic cancer, review techniques for clearing and the 3D reconstruction of digitized microscope slides, and provide examples that illustrate how 3D visualization of human pancreatic cancer at the microscopic level has revealed features not apparent in 2D microscopy and, in so doing, has closed the gap between bench and bedside. Compared with animal models and 2D microscopy, studies of human tissues in 3D can reveal the difference between what can happen and what does happen in human cancers.