Discontinuous Pattern Research Articles

Using the Total Apparent Spacing Approach to Optimize Foundation Drain Orientations

ABSTRACT Design of foundation drain holes in bedrock where fractures control the permeability may be optimized based on the discontinuity pattern, specifically the spacing and orientation of the predominant discontinuity sets. When suitable representative outcrops are available, either naturally or by means of excavation, joint spacing and orientation can be measured directly by traditional methods using a measuring tape and compass or pocket transit or newer methods using computer software to measure virtual joint surfaces within a digital terrain model developed from digital photogrammetry or light detection and ranging (LiDAR) surveys. When suitable outcrops are not available, joint spacing and orientation can be measured using oriented core drilling techniques or downhole imaging tools (e.g., optical and acoustic sondes) that provide digital images of the borehole wall. With an understanding of the bedrock jointing pattern obtained from one or more of the above methods, the total apparent spacing (TAS) approach can be used to optimize the orientation of drain holes. The TAS approach employs the vector dot product formula to minimize the total apparent spacing between discontinuities and maximize the number of discontinuities intercepted by the drain hole. The TAS approach was used to optimize the orientation of foundation drain holes during rehabilitation of the Gilboa Dam in Schoharie County, NY. The TAS approach has other applications, e.g., optimizing the orientation of exploratory core holes to collect discontinuity data or the orientation of grout holes for foundation grouting.

Peridynamics simulations of the damage of reinforced concrete structures under radial blasting

Concrete is prone to damage under explosive loads, which can cause a large number of casualties and property losses. The concrete fragmentation process during explosion is transient and dynamic, and the experimental measurement of such events is difficult and risky to conduct, and the intermediate explosion process is difficult to observe in the experimental tests. Therefore, the numerical simulation is an ideal method to model and simulate the explosion process of concrete. Different from the traditional finite element method, Peridynamics (PD) method uses the spatial integral equation to replace the traditional local differential equation to solve the fragmentation problem with massive and complex discontinuous patterns. In this study, a peridynamics (PD) model is developed to simulate the failure process of reinforced concrete (RC) structures under radial blasting. Concrete PD models with different cavity sizes and reinforcement conditions were established and calibrated with the experimental data. We find that the crack growth and damage pattern obtained in the peridynamics simulation is consistent with the experiment test results, which verifies the feasibility of peridynamics method as a modeling tool for modeling concrete damage under explosive load and for evaluating anti-explosion performance of RC concrete structures.

Associations of different definitions of iron deficiency with cardiac structure and function, congestion, exercise capacity and prognosis in heart failure

Abstract Background It is uncertain how best to diagnose iron deficiency (ID) in patients with heart failure (HF) as different ID definitions have been proposed with discordant results. Objectives To assess the relationship of different ID definitions with cardiac structure and function, congestion, exercise capacity, and prognosis in outpatients with HF. Methods ID was defined according to guidelines (G-ID: ferritin <100 ng/mL or ferritin 100-299 ng/mL with transferrin saturation [TSAT] <20%) or as TSAT <20%. Alternative definitions (iron <13 ¼mol/L, ferritin <100 and <300 ng/mL) were explored. Relationship with rest and exercise ultrasound findings, cardiopulmonary exercise testing and a composite endpoint of cardiovascular hospitalisations or all-cause mortality were assessed. Results Of 1502 patients (72% with left ventricular ejection fraction [LVEF] ≥50%), 471 (31%) had TSAT <20%, while 728 (48%) had G-ID. Compared to those without ID, patients with TSAT <20% or G-ID showed impaired cardiac structure and function at rest and peak exercise and lower peak oxygen consumption; they were also more likely to display a discontinuous renal venous flow pattern and more lung B-lines. Only TSAT <20% was associated with significant inferior vena cava dilatation. Lower TSAT, iron and haemoglobin were associated with more severe effort intolerance and ultrasound signs of congestion, while ferritin and LVEF were not (Picture 1). During a median follow-up of 16 months, 62 (4%) patients died, and 244 (16%) were hospitalised for cardiovascular reasons. No patients were hospitalised immediately after the enrolment visit because of clinical findings. At Kaplan-Meier analyses, TSAT <20% was associated with a greater risk of adverse events, as were iron ≤13 ¼mol/L, ferritin ≥300 ng/mL and <100 ng/mL (p <0.01 vs ferritin 100-299 ng/mL) and G-ID (Picture 2). After adjusting for age, sex, diabetes, haemoglobin, estimated glomerular filtration rate (eGFR), NT-proBNP, rest LVEF and peak VO2 <16 mL/kg/min, TSAT <20% and iron ≤13 ¼mol/L were associated with worse outcomes (hazard ratio 2.41, 95% confidence interval 1.85-3.14 and 1.90, 1.46-2.47), while G-ID or ferritin <100 or <300 ng/mL were not (Picture 1). Conclusions In outpatients with HF, TSAT <20% is more consistently associated with echocardiographic signs of poorer functional capacity and multi-organ congestion than other ID definitions. TSAT <20% and iron ≤13 ¼mol/L, but not G-ID or ferritin-based ID, seem to predict a worse prognosis.Picture 1Picture 2

The Most Common Side Effects, Concerns and Discontinuation Patterns of Oral Contraceptive Pills Among Polish Women: A Cross-Sectional Study.

Over the decade, variety and effectiveness of contraception methods have greatly improved, resulting in increased popularity of oral contraceptive pills (OCPs). However, hormonal contraception carries the risk of multiple side effects. The lack of sufficient knowledge often leads to the development of health concerns, which can affect patient's adherence. The aim of our research was to describe a side effect profile of OCPs and assess the most frequent concerns and discontinuation reasons in Polish women. The survey included questions regarding OCPs utilization patterns, side effects, health concerns and attitudes of the responders. This cross-sectional study was based on a survey, which was distributed online and open from 29 April to 15 May 2022. The survey included questions regarding OCPs utilization patterns, side effects, health concerns and attitudes of the responders. Out of 1699 respondents, the current OCPs intake was reported by two thirds of women and 22% had a history of using them in the past. Seventy-nine percent of all OCPs users experienced adverse effects while 9% reported having concerns about safety and potential adverse effects. Decreased libido and weight gain were the most significant reasons for ceasing hormonal contraception. Moreover, the most common concerns and the most unfavorable side effects varied in different age groups. The occurrence of anxiety depended on age and education. Healthcare professionals prescribing OCPs should provide their patients with comprehensive counseling. Understanding and addressing concerns of young women can improve their compliance and reduce the number of unintended pregnancies.

Gravity wave interaction with compressive VLFS in the presence of thick porous bed

The present study deals with the problem of oblique wave scattering by a finite floating elastic plate over a thick porous bed. A potential flow-coupled thin-elastic plate model has been developed, and the wave flow model resembling the physical scenario is framed into a boundary value problem (BVP). A semi-analytical method has been employed to obtain the hydrodynamic coefficients following the numerical and physical illustrations by varying different geometrical parameters. Prior to wave interaction, dispersive roots are thoroughly analyzed, and a critical frequency is observed above which the group velocity is negative. Within this range, minimum reflection and maximum transmission occur due to the high porosity of the seabed. A discontinuous pattern in the reflection coefficient is observed within the blocking range, which mainly exists for high compression. The findings of this work may be highly valuable for Very Large Floating Structures in marine settings, particularly in situations where interactions are primarily influenced by the thick porous beds.

Long-term retention rate, adverse event temporal patterns and rescue treatment strategies of mycophenolate mofetil in systemic sclerosis: insights from real-life.

Mycophenolate mofetil (MMF) is a mainstay for the treatment of systemic sclerosis (SSc). The occurrence and implications of MMF-related adverse events on drug retention rates in real life remain poorly defined. We aimed to determine the MMF retention rate and to investigate the causes and patterns of discontinuation, adverse events (AEs) and treatment options used after discontinuation. SSc patients who started MMF treatment underwent a retrospective longitudinal assessment for up to 5 years. We documented the incidence, predictors, and impacts of MMF treatment on gastrointestinal intolerance, infections, laboratory abnormalities, and cancer. Rescue strategies implemented after MMF discontinuation were recorded. The 5-year MMF retention rate of 554 patients stood at 70.7% and 19.6% of them stopped MMF due to AEs. One out of every four patients experienced a dose reduction or discontinuation of MMF due to AEs, with gastrointestinal intolerance being the predominant cause. The 5-year cumulative incidence rates for gastrointestinal intolerance, cancer, severe infections, and laboratory toxicity leading to MMF discontinuation were 6.4%, 4.1%, 3.1%, and 2.1%, respectively. Lower respiratory tract was the most affected, with bacteria being the predominant causative agent. Intestinal and pulmonary circulation involvement were tied to elevated AE rates and MMF discontinuation. The most common approaches post-MMF cessation were "watch and wait" and switch to rituximab. MMF use in SSc appears to be limited by the occurrence of AEs, both in terms of persistence and dosing of the drug. Rescue options after MMF discontinuation are limited and many patients remain without immunosuppressant.

An effective way to monitor the population of juvenile horseshoe crabs in the Beibu Gulf of China

Population conservation of horseshoe crab is urgently required in China as their population is declining dramatically. However, conservation efforts are severely constrained by the lack of information on the population dynamics of the species. Here, a citizen science-based investigation was conducted to continuously monitor the population dynamics of juvenile Tachypleus tridentatus and Carcinoscorpius rotundicauda in the Beibu Gulf of China over five years. A low abundance of horseshoe crabs was observed at all stations. T. tridentatus was primarily observed in the eastern of Beibu Gulf, with an abundance (0.179 ind/100 m2) larger than that of C. rotundicauda (0.007 ind/100 m2). The prosomal width range of T. tridentatus was between 9.0 and 138.0 mm while that of C. rotundicauda was between 20.0 and 111.0 mm, representing their different age distribution patterns. A continuous distribution pattern from 3rd to 14th instar was observed in the T. tridentatus population, whereas a discontinuous distribution pattern from 6th to 16th instars was observed in the C. rotundicauda population. This instar distribution pattern implies that these areas are crucial nursery habitats for the two species. No horseshoe crab within the 1st to 2nd instars (for T. tridentatus) or before 6th instar (for C. rotundicauda) were observed within five years, indicating a declining age structure with few natural births. It was concluded that the declining population would exacerbate the risk of endangered horseshoe crab. There is an urgent need to strengthen the protection of horseshoe crab in the Beibu Gulf, particularly to protect their nursery habitats. The value of long-term citizen science based-monitoring was highlighted, which greatly increased public awareness of horseshoe crab protection.

Discontinuation of Antidepressants and the Risk of Medication Resumption among Community-Dwelling Older Adults with Depression in the US.

Antidepressants are among the most prescribed drugs in the US, but the current treatment patterns and modalities among older adults are unclear. This study assessed the patterns of discontinuation of antidepressants and the risk of medication resumption among community-dwelling older adults with depression. Using Medicare Current Beneficiary Survey (MCBS) data from 2015-2019, we identified 1084 beneficiaries with depression who newly initiated serotonergic antidepressants. The risk of medication resumption was explored using survival analysis. The median duration of continuous medication was 90 days. However, about 30% of patients had a treatment duration of 30 days or shorter, 26% for 31-90 days, 15% for 91-180 days, and 30% for 181 days or more. After adjusting for all covariates, patients with less than 30 days of continuous medication were half as likely to resume the medications compared to those with 91-180 days (HR: 0.49 (95% CI: 0.37, 0.65)). Nearly one-third of older adults used an antidepressant medication for a short duration with a lower risk of medication resumption. A shorter treatment duration without resumption might suggest over-prescription of antidepressants among community-dwelling older adults.

Non-Medical Switching or Discontinuation Patterns among Patients with Non-Valvular Atrial Fibrillation Treated with Direct Oral Anticoagulants in the United States: A Claims-Based Analysis.

This study assessed direct-acting oral anticoagulant (DOAC) switching/discontinuation patterns in patients with non-valvular atrial fibrillation (NVAF) in 2019, by quarter (Q1-Q4), and associated socioeconomic risk factors. Adults with NVAF initiating stable DOAC treatment (July 2018-December 2018) were selected from Symphony Health Solutions' Patient Transactional Datasets (April 2017-January 2021). Switching/discontinuation rates were reported in 2019 Q1-Q4, separately. Non-medical switching/discontinuation (NMSD) was defined as the difference between switching/discontinuation rates in Q1 and mean rates across Q2-Q4. The associations of socioeconomic factors with switching/discontinuation were assessed. Of 46,793 patients (78.7% ≥ 65 years; 52.6% male; 7.7% Black), 18.0% switched/discontinued their initial DOAC in Q1 vs. 8.8% on average in Q2-Q4, corresponding to an NMSD of 9.2%. During the quarter following the switch/discontinuation, more patients who switched/discontinued in Q1 remained untreated (Q1: 77.0%; Q2: 74.3%; Q3: 71.2%) and fewer reinitiated initial DOAC (Q1: 17.6%; Q2: 20.8%; Q3: 24.0%). Factors associated with the risk of switching/discontinuation in Q1 were race, age, gender, insurance type, and household income (all p < 0.05). More patients with NVAF switched/discontinued DOACs in Q1 vs. Q2-Q4, and more of them tended to remain untreated relative to those who switched/discontinued later in the year, suggesting a potential long-term impact of NMSD. Findings on factors associated with switching/discontinuation highlight potential socioeconomic discrepancies in treatment continuity.

50857 Treatment Discontinuation Patterns in Patients With Psoriasis Receiving Apremilast in North America: A Registry-Based Analysis

50857 Treatment Discontinuation Patterns in Patients With Psoriasis Receiving Apremilast in North America: A Registry-Based Analysis

Ray and Halo Impact Craters on Ganymede: Fingerprint for Decoding Ganymede's Crustal Structure

AbstractImpact craters are a unique tool not only for inferring ages of planetary surfaces and examining geological processes, but also for exploring subsurface properties. We use ejecta blankets as proxies to obtain insights into the subsurface characteristics and the vertical stratification of Ganymede's icy crust. We investigated 36 prominent ray and halo craters using images acquired during the Voyager, Galileo, and Juno spacecraft missions. These craters exhibit diverse characteristics, including dark rays, bright rays, or their combination, in both continuous and discontinuous patterns as well as dark and bright halos. Dark halo craters (DHCs) have the smallest radial extents of their dark ejecta deposits, while dark ray craters (DRCs) have the largest. DRCs in dark terrain suggest a thickness of less than ∼2 km based on their excavation depths. DRCs and DHCs craters located in light terrain (LT) reveal significant heterogeneity in the uppermost portions of icy crust at various locations. DRCs and DHCs in the LT require the presence of at least one layer of dark material. This is the case if the LT is formed by tectonic rifting and graben formation. In contrast, if the LT is formed by tectonic spreading, bright halo and ray craters are expected to form.

Biomass flame spectroscopy technique to identify wood species through spectral emission during combustion processes

The energy emitted by a flame and its spectra provide critical information about fuels, such as energy type, temperature, and molecular properties. While traditionally used to analyze combustion, we introduce a spectral-time-based index, optical calorific power (OCP), to calculate the total energy released per mass unit (J/Kg), relating to the calorific value of wood-based fuels. Using novel optical variables and machine learning, we identified different wood species during the combustion of the wood samples. Homogeneous samples of four wood species (sapwood and heartwood) were ignited in a temperature-controlled furnace. Spectra were measured using a calibrated spectrophotometer in the 450–900 nm range with a 100ms integration time. Continuous and discontinuous spectral patterns were observed in all samples, used to calculate spectral-time-based optical variables, and separated using the AirPLS algorithm. Discontinuous spectra correlated with Na and K emissions (589.4 nm and 766.5 nm, respectively). Continuous spectra were analyzed to determine optical variables such as flame temperature (K), total continuous radiation (TCR, μW/cm2), and total continuous energy (TCE, μJ). Five supervised classification models, XGBoost, LR, SVM, LDA, and RF, were trained using normalized physical parameters and optical variables with stratified cross-validation. The proposed optical variables yielded an identification accuracy of 93%, precision of 95%, and recall of 93% during combustion using the XGBoost method. These promising results demonstrate the potential of our method for accurately identifying wood species, while offering a cost-effective and novel alternative to NIR-SWIR reflectance spectral identification techniques.

Generalized denoising network LGCT-Net for various types of ESPI wrapped phase patterns

In this paper, we propose a generalized network based on our proposed Local-Global Channel Transformer (LGCT) module for denoising various types of ESPI wrapped phase patterns (including low-density, medium-density, high-density, variable-density, and discontinuous phase patterns). The Conv + BN + ReLU layer consists of convolution (Conv), batch normalization (BN), and the rectified linear unit (Relu) in series. The generalized network LGCT-Net interleaves four LGCT modules with five Conv + BN + ReLU layers in a dense connection manner. We propose the LGCT Module by stacking three Dilated-Group Convolution blocks (DGC block), a Contextual Transformer block (CoT block), and an Efficient Channel Attention block (ECA block). The LGCT module simultaneously leverages the local context extraction capability of convolutions and the powerful global information extraction capability of a transformer. Additionally, it performs feature extraction in both spatial and channel dimensions. We also create a diverse ESPI wrapped phase pattern denoising dataset with various densities, shapes, noise levels, and discontinuity. We successfully train the LGCT-Net without any preprocessing or postprocessing steps. We evaluate the performance of our method on simulated and experimental ESPI wrapped phase patterns with discontinuity and different densities. Then we compare it with previously published denoising methods PEARLS, HDCNN, ADCNN, and DBDNet quantitatively and qualitatively. The results show that our method facilitates the reduction of speckle noise and the enhancement of fine details while preserving structure and shape, outperforming the compared methods. In the end, we apply our method to dynamic measurements of nuclear graphite ESPI phase patterns at different times. And then performing phase unwrapping on the filtered phase patterns, we achieve successful results.

Classification of Time–Frequency Maps of Guided Waves Using Foreground Extraction

Guided waves propagating in mechanical structures have proved to be an essential technique for applications, such as structural health monitoring. However, it is a well-known problem that when using non-stationary guided wave signals, dispersion, and high-order vibrational modes are excited, it becomes cumbersome to detect and identify relevant information. A typical method for the characterization of these non-stationary signals is based on time–frequency (TF) mapping techniques. This method produces 2D images, allowing the study of specific vibration modes and their evolution over time. However, this approach has low resolution, increases the size of the data, and introduces redundant information, making it difficult to extract relevant features for their accurate identification and classification. This paper presents a method for identifying discontinuities by analyzing the data in the TF maps of Lamb wave signals. Singular Value Decomposition (SVD) for low-rank optimization and then perform foreground feature extraction on the maps were proposed. These foreground features are then analyzed using Principal Component Analysis (PCA). Unlike traditional PCA, which operates on vectorized images, our approach focuses on the correlation between coordinates within the maps. This modification enhances feature detection and enables the classification of discontinuities within the maps. To evaluate unsupervised clustering of the dimensionally reduced data obtained from PCA, we experimentally tested our method using broadband Lamb waves with various vibrational modes interacting with different types of discontinuity patterns in a thin aluminum plate. A Support Vector Machine (SVM) classifier was then implemented for classification. The results of the experimental data yielded good classification effectiveness within reasonably low computational time despite the large matrixes of the TF maps used.

Crack layer modeling of butt-fusion joints induced slow crack growth in high-density polyethylene pipes

The design and reliability of high-density polyethylene (HDPE) pipes can be dictated by the damage tolerance of their butt-fusion joints. A slow crack growth (SCG) model based on the crack layer theory for HDPE pipes internal and external circumferential and butt-fusion joints cracks is developed to investigate the discontinuous SCG behavior and lifetime tf variations. Using the developed model, the discontinuous SCG patterns, jump lengths and lifetime tf can be accurately simulated. In addition, the effects of pipes standard dimension ratio, internal pressure, and temperature on the SCG behavior and tf are investigated. Compared to pipe cracks, it was found that butt-fusion induced SCG can reduce the pipe tf > 60 %. Unlike longitudinal cracks, tf of external circumferential cracks, were found shorter than the internal ones, mandating an earlier evaluation. The new SCG model shows good accuracy with the experimental results. The same substitute geometry approach used can be followed for othercomplex designs, which aids in establishing a fundamental methodology for more realistic lifetime predictions.

Wykorzystanie metody radaru penetrującego grunt w badaniu gleby zanieczyszczonej węglowodorami w obszarze Navodari - Rumunia

Ground penetrating radar (GPR) is a very useful geophysical method for use in hydrogeologic and near-surface mapping studies. It can be used to study contaminants in groundwater, subsurface faulting, and underground cavities (natural or man-made), all of which pose potentially dangerous geological hazards. The GPR technique is similar in principle to seismic reflection and sonar techniques. The propagation of the radar signal depends on the frequency-dependent electrical properties of the ground.Electrical conductivity of the soil or rock materials along the propagation paths introduces significant absorptive losses which limit the depth of penetration into the earth formations and is primarily dependent upon the moisture content and mineralization present.Reflected signals are amplified, and transformed to the audio-frequency range, recorded, processed, and displayed. From the recorded display, subsurface features such as soil/ soil, soil/rock, and unsaturated/saturated interfaces can be identified. In addition, the presence of floating hydrocarbons on the water table, the geometry of contaminant plumes, and the location of buried cables, pipes, drums, and tanks can be detected. The GPR data are presented as a two-dimensional depth profile along a scanned traverse line in which the vertical axis is two-way travel time measured in nanoseconds. The location of hydrocarbon contamination in the ground using the GPR method is based mainly on information taken from reflected signals. In the cases investigated in Romania contaminated sites (Navodari area), such signals were very rarely recorded. A long time after spillage, contamination takes the form of plumes with different size and distribution, which depends on the geological and hydraulic properties of the ground. The survey discussed in this paper was carried out using the GPR system-Noggin with two antennas (250 and 500mHz) Data collected were processed using software(EKKO_Project™ GPR Data Analysis) to produce 2D radargram in time scale. The presence of contaminant plumes as well as the water table are observed in the GPR sections at depths approximately of 0.5 to 1.5 m. In the GPR section, the oil contaminated layer exhibits discontinuous, subparallel, and chaotic high amplitude reflection patterns. Promising results were also obtained in the GPR survey where three obvious reflection patterns representing the top sand-silt layer, oil-contaminated zone and, the underlying thick soft clay were detected in all 2D radargrams of the GPR traverse lines.

Dissimilarity of megabenthic community structure between deep-water seamounts with cobalt-rich crusts: Case study in the northwestern Pacific Ocean

As anthropogenic disturbance on deep-sea seamount ecosystems grows, there is an urgent need for a better understanding of the biodiversity and community structure in benthic ecosystems, which can vary at local and regional scales. A survey of the benthic megafauna on two adjacent deep-water seamounts in the northwestern Pacific Ocean was conducted, which are covered by cobalt-rich crusts, to assess the biodiversity patterns and dissimilarity of assemblage composition. Based on a multidisciplinary dataset generated from video recordings, multibeam bathymetry data, and near-bottom currents, environmental and spatial factors impacting the megabenthic communities were explored. Results showed that these two deep-water seamounts were dominated by hexactinellids, crinoids, and octocorals. The seamounts were able to support diverse and moderately abundant megafauna, with a total of 6436 individuals classified into 94 morphospecies. The survey covered a distance of 52.2 km across a depth range of 1421–3335 m, revealing multiple distinct megabenthic assemblages. The megabenthic communities of the two deep-water seamounts, with comparable environmental conditions, exhibited similarities in overall density, richness, and faunal lists, while dissimilarities in the relative abundance of taxa and assemblage composition. No gradual depth-related change in terms of abundance, richness, or species turnover was observed across the two seamounts, despite the statistical significance of depth in structuring the overall communities. The spatial distribution of megabenthic communities displayed a discontinuous and patchy pattern throughout the two deep-water seamounts. This patchiness was driven by the interactive effects of multiple environmental factors. Near-bottom currents and microhabitat features were the primary drivers influencing their dissimilarities in megabenthic community structure. This case study on the megabenthic community structure of two adjacent seamounts with cobalt-rich crusts can serve as an environmental baseline, providing a reference status for the conservation and management of seamount ecosystems, particularly valuable for areas being considered for deep-sea mining.

1946-LB: Patterns of Insulin Discontinuation in Youth with New-Onset Type 2 Diabetes

1946-LB: Patterns of Insulin Discontinuation in Youth with New-Onset Type 2 Diabetes

A pre-Campanian Ignimbrite techno-cultural shift in the Aurignacian sequence of Grotta di Castelcivita, southern Italy

The Aurignacian is the first European technocomplex assigned to Homo sapiens recognized across a wide geographic extent. Although archaeologists have identified marked chrono-cultural shifts within the Aurignacian mostly by examining the techno-typological variations of stone and osseous tools, unraveling the underlying processes driving these changes remains a significant scientific challenge. Scholars have, for instance, hypothesized that the Campanian Ignimbrite (CI) super-eruption and the climatic deterioration associated with the onset of Heinrich Event 4 had a substantial impact on European foraging groups. The technological shift from the Protoaurignacian to the Early Aurignacian is regarded as an archaeological manifestation of adaptation to changing environments. However, some of the most crucial regions and stratigraphic sequences for testing these scenarios have been overlooked. In this study, we delve into the high-resolution stratigraphic sequence of Grotta di Castelcivita in southern Italy. Here, the Uluzzian is followed by three Aurignacian layers, sealed by the eruptive units of the CI. Employing a comprehensive range of quantitative methods—encompassing attribute analysis, 3D model analysis, and geometric morphometrics—we demonstrate that the key technological feature commonly associated with the Early Aurignacian developed well before the deposition of the CI tephra. Our study provides thus the first direct evidence that the volcanic super-eruption played no role in this cultural process. Furthermore, we show that local paleo-environmental proxies do not correlate with the identified patterns of cultural continuity and discontinuity. Consequently, we propose alternative research paths to explore the role of demography and regional trajectories in the development of the Upper Paleolithic.

Producing peripheries: morphology and habitability in the conurbations of Cuenca, Ecuador

The expansion of Latin American intermediate cities has left irregular and discontinuous occupation patterns in their peripheral territories. In appearance, the configurations of the urban edges do not have relevant differences. In fact, each morphological structure is heterogeneous and has its own behaviors, different occupation motivations, and diverse resulting consolidated models. In Cuenca, Ecuador, these diffuse zones between the urban and rural limits are marked by segregation dynamics and dependence on the consolidated center and have the lowest quality-of-life indexes in the city. In this context, the objective of the research was to find a possible relationship between the types of peripheral morphologies and the levels of urban habitability of four city urban centers, using a quantitative methodological design with a two-stage correlational scope. Initially, urban morphologies were classified, and the habitability levels were rated separately, applying independent instruments. Then, the results were cross-checked to describe possible links between variables. The findings highlight significant disparities in habitability between conurbations and define an apparent direct correlation between the two dimensions of analysis.