bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of the ARRIVE Trial on Stillbirth Rates in Nulliparous Individuals
Authors: Atwani Rula , Saade George , Kawakita Tetsuya
Published: August 2024

Objective We aim to examine the population-level rates of induction, stillbirth, perinatal mortality, and neonatal death before and after the ARRIVE (A Randomized Trial of Induction Versus Expectant Management) trial.

Study Design This study was a cross-sectional analysis of publicly available U.S. Live Birth data linked with Infant Death and Fetal Death certificate data from National Vital Statistics Online. We limited analyses to nulliparous individuals with singleton pregnancy and cephalic presentation who delivered at 39 weeks or greater. The pre- and post-ARRIVE periods spanned from August 2016 to July 2018, and from January 2019 to December 2020, respectively. Our primary outcome was a stillbirth. Secondary outcomes included induction of labor, perinatal mortality, and neonatal death. Outcomes were compared between the pre- and post-ARRIVE periods. Modified Poisson regression was used to calculate adjusted relative risks (aRRs).

Results Of 2,817,071 births, there were 1,454,346 births in the pre-ARRIVE period and 1,362,725 in the post-ARRIVE period; there were 1,196 and 1,062 stillbirths in the pre- and post-ARRIVE periods, respectively. Compared to the pre-ARRIVE period, the post-ARRIVE period was not associated with a significant decrease in the risk of stillbirth at 39 weeks or greater (aRR = 0.92 [95% confidence interval (95% CI): 0.85–1.00]) and stillbirth at 40 weeks or greater (aRR = 0.92 [95% CI: 0.82–1.04]). Compared to the pre-ARRIVE trial period, the post-ARRIVE trial was associated with increased rates of induction of labor at 39 weeks (aRR = 1.37 [95% CI: 1.37–1.38]) and 40 weeks (aRR = 1.24 [95% CI: 1.24–1.25]. Similar to stillbirth, there was no significant decrease in the risk of perinatal mortality at 39 weeks or greater or 40 weeks or greater. There was also no statistically significant change in neonatal death rates at 39 weeks or greater or at 40 weeks or greater.

Conclusion The increase in induction of labor at 39 weeks was not large enough to impact the stillbirth rate at 39 weeks or greater.

Key Points
Elucidating the sustainability of 700 y of Inuvialuit beluga whale hunting in the Mackenzie River Delta, Northwest Territories, Canada
Authors: Skovrind Mikkel , Louis Marie , Ferguson Steven H. , Glazov Dmitry M. , Litovka Dennis I. , Loseto Lisa , Meschersky Ilya G. , Miller Mariah M. , Petr Martin , Postma Lianne , Rozhnov Viatcheslav V. , Scott Michael , Westbury Michael V. , Szpak Paul , Friesen T. Max , Lorenzen Eline D.
Published: August 2024

Beluga whales play a critical role in the subsistence economies and cultural heritage of Indigenous communities across the Arctic, yet the effects of Indigenous hunting on beluga whales remain unknown. Here, we integrate paleogenomics, genetic simulations, and stable
δ
13
C and
δ
15
N isotope analysis to investigate 700 y of beluga subsistence hunting in the Mackenzie Delta area of northwestern Canada. Genetic identification of the zooarchaeological remains, which is based on radiocarbon dating, span three time periods (1290 to 1440 CE; 1450 to 1650 CE; 1800 to 1870 CE), indicates shifts across time in the sex ratio of the harvested belugas. The equal number of females and males harvested in 1450 to 1650 CE versus more males harvested in the two other time periods may reflect changes in hunting practices or temporal shifts in beluga availability. We find temporal shifts and sex-based differences in δ
13
C of the harvested belugas across time, suggesting historical adaptability in the foraging ecology of the whales. We uncovered distinct mitochondrial diversity unique to the Mackenzie Delta belugas, but found no changes in nuclear genomic diversity nor any substructuring across time. Our findings indicate the genomic stability and continuity of the Mackenzie Delta beluga population across the 700 y surveyed, indicating the impact of Inuvialuit subsistence harvests on the genetic diversity of contemporary beluga individuals has been negligible.
Phase separation of PML/RARα and BRD4 coassembled microspeckles governs transcriptional dysregulation in acute promyelocytic leukemia
Authors: Zhang Yi , Lou Jiacheng , Liu Yabin , Jin Peng , Tan Yun , Song Huan , Jin Wen , Wang Dan , Dong Fangyi , Wu Shishuang , Fang Hai , Chen Saijuan , Chen Zhu , Wang Kankan
Published: August 2024

In acute promyelocytic leukemia (APL), the promyelocytic leukemia-retinoic acid receptor alpha (PML/RARα) fusion protein destroys PML nuclear bodies (NBs), leading to the formation of microspeckles. However, our understanding, largely learned from morphological observations, lacks insight into the mechanisms behind PML/RARα-mediated microspeckle formation and its role in APL leukemogenesis. This study presents evidence uncovering liquid–liquid phase separation (LLPS) as a key mechanism in the formation of PML/RARα-mediated microspeckles. This process is facilitated by the intrinsically disordered region containing a large portion of PML and a smaller segment of RARα. We demonstrate the coassembly of bromodomain-containing protein 4 (BRD4) within PML/RARα-mediated condensates, differing from wild-type PML-formed NBs. In the absence of PML/RARα, PML NBs and BRD4 puncta exist as two independent phases, but the presence of PML/RARα disrupts PML NBs and redistributes PML and BRD4 into a distinct phase, forming PML/RARα-assembled microspeckles. Genome-wide profiling reveals a PML/RARα-induced BRD4 redistribution across the genome, with preferential binding to super-enhancers and broad-promoters (SEBPs). Mechanistically, BRD4 is recruited by PML/RARα into nuclear condensates, facilitating BRD4 chromatin binding to exert transcriptional activation essential for APL survival. Perturbing LLPS through chemical inhibition (1, 6-hexanediol) significantly reduces chromatin co-occupancy of PML/RARα and BRD4, attenuating their target gene activation. Finally, a series of experimental validations in primary APL patient samples confirm that PML/RARα forms microspeckles through condensates, recruits BRD4 to coassemble condensates, and co-occupies SEBP regions. Our findings elucidate the biophysical, pathological, and transcriptional dynamics of PML/RARα-assembled microspeckles, underscoring the importance of BRD4 in mediating transcriptional activation that enables PML/RARα to initiate APL.
Are non-native speakers sensitive to microvariation in anaphora resolution?
Authors: Teixeira Joana , Fiéis Alexandra , Madeira Ana
Published: August 2024

This study investigates anaphora resolution in L2 European Portuguese by Italian and Spanish native speakers to
examine whether learners are sensitive to microvariation among these null subject Romance languages. Participants were 25 adult L1 EP
speakers, 69 L1 Italian, and 42 L1 Spanish adult learners of EP at three levels: upper–intermediate, advanced, and near-native.
They completed an untimed and a speeded multiple-choice task crossing the variables animacy of the matrix object
and type of embedded subject. Results indicate that sensitivity to microvariation develops as L2 proficiency
increases. However, learners’ performance remains permanently unstable in the areas where the L1 and the L2 differ, which is only
visible in the speeded task. Our findings challenge the idea that the L1 plays a minor role in anaphora resolution and have
implications for the Interface Hypothesis.
Ordering a series of turn-initial particles
Authors: Mazeland Harrie
Published: August 2024

The paper is an attempt to describe the principles behind the ordering of a series of four
different particles – hee ‘hey’,
ja ‘yes’, eh ‘eh’, and nou ‘now’/’well’ – in the beginning of a
sequence-initiating turn in which the speaker launches a new activity framework. A surprising result of the analysis is that it shows that the speaker lays the
groundwork for a new activity framework in a turn-initial trajectory that indexes the turn’s position within the
overall-structural organization of the talk both at the local level of the organization of subsequent sequences and at
the global level of the organization of activities. The positioning of each particle in the series locates the order of organization by reference to
which it operates. The study’s methodology – using
multiple collection studies to establish the orientations that are at work – is an attempt to find an appropriate
heuristic for developing an empirically plausible analysis of a complex configuration of single-case phenomena.
E anche-prefaced other-expansions in multi-person interaction
Authors: Calabria Virginia , De Stefani Elwys
Published: August 2024

This chapter investigates a practice used in Italian talk-in-interaction, whereby a speaker self-selects and expands the prior speaker’s talk with a
grammatically dependent turn prefaced by e
anche ‘and also’. The practice is used either to affiliate or disaffiliate with prior talk, and occurs in
different gaze constellations: (1) a speaker may gaze
at the prior speaker and subsequently initiate an e anche-prefaced other-expansion, thus receiving the prior speaker’s gaze; (2)
speakers may establish mutual gaze before, or precisely at the moment at which the other-expansion is articulated.
Such gaze behavior is sensitive to the action speakers accomplish. This chapter offers advances in Interactional Linguistics by examining a previously
neglected grammatical resource (e anche) and concomitant gaze-behavior in multi-person
interaction.
Noticing and assessing nature
Authors: Auer Peter , Laner Barbara , Pfeiffer Martin , Botsch Kerstin
Published: August 2024

We analyze how walkers employ a verbal format, i.e., the combination of a perception imperative followed by a wie ‘how’-exclamative (e.g., KUCK ma wie TRAUMhaft das
is; ‘look PTCL how wonderful that is’), in its multimodal embedding, thus contributing to a multimodal extension of interactional linguistics. The analysis heavily relies on mobile
eye-tracking as a method to collect naturally occurring data. It is argued that this kind of analysis would not be
possible without the use of this novel technology. We focus on the role of the verbal format in the process of
transforming individual perceptions into intersubjective experiences of nature, for which the precise documentation of
gaze is essential. It is shown that the
interactional function of this combined format is to draw the co-walker’s attention to an object in the surroundings
and to express an affective stance towards it, treating
the noticed referent as noteworthy and remarkable.
High-performance Self-polarized piezoelectric PVDF composites films for tribo-electric nanogenerators
Authors: Lu Jiaqi , Hazarika Dinku
Published: August 2024

This study introduces a novel and efficient methodology for enhancing the local dipole moment and β-phase fraction in polyvinylidene fluoride (PVDF) piezoelectric polymer composites through the incorporation of hydroxylated barium titanate (H-BTO) nanoparticles, combined with a directional freeze-drying technique. This approach markedly increases the β-phase fraction within the composites. Through the optimization of H-BTO nanoparticle concentration, we achieve a strengthened interfacial bond between the inorganic nanofillers and the organic polymer matrix. This enhancement not only elevates the β-phase fraction (F(β)) but also enables significant piezoelectric effects without the necessity for electric polarization. Utilizing the freeze-drying PVDF/H-BTO composite films and PA6 membranes, we construct a triboelectric nanogenerator (TENG) that exhibits high-performance outputs. This TENG proved capable of powering a temperature and humidity sensor, which transmitted real-time environmental data wirelessly to a smartphone via Bluetooth. The findings of this study underscore the effectiveness of our strategy in fabricating high-performance piezoelectric PVDF composite films and suggest potential for significant advancements in the domain of piezoelectric materials engineering.
Ultra-sensitive pseudocapacitive iontronic pressure sensor for wearable snoring and apnea detection
Authors: Li Jie , Zhang Kaihang
Published: August 2024

Snoring is a common phenomenon, but its potential implications have been severely underestimated. In this study, we introduce a flexible pseudocapacitive iontronic pressure sensor with ultra-high sensitivity, achieved by combining MXene electrodes with ionic film. This pressure sensor demonstrates remarkable capabilities, including an ultra-high sensitivity of 3084.4 kPa−1, a comprehensive pressure range up to 300 kPa, an extremely low detection limit of 1 Pa, and superior stability. Utilizing its exceptional performance, the sensor has been effectively applied in respiratory monitoring, where it can precisely detect critical conditions such as snoring and apnea. This work has demonstrated its potential application prospects in medical monitoring.
Ultra-sensitive humidity sensing based on Coherent perfect absorber-lasing system
Authors: Wu Jianhui , Li Jie
Published: August 2024

As a singularity in non-Hermitian physics, coherent perfect absorber-lasing (CPAL) point theoretically has an infinite quality factor and can detect small perturbations, so it has potential applications in ultra-sensitive sensors. However, in the radio frequency field, due to deviations in actual components, the system will deviate from the CPAL point and the performance will degrade significantly (the output coefficient amplitude is only 30 dB). At the same time, actual sensing research is also very lacking. Based on these, we demonstrate a CPAL-based sensor system that increases its output coefficient amplitude to 60dB. When using the lasing state as the sensing mode, it has a capacitance detection accuracy of 10 fF. Then a high-frequency capacitive humidity sensor based on polyaniline/graphene oxide/titanium dioxide film is designed. The heterojunction formed between these materials increases the number of active sites for adsorbing water molecules. With the ultra-high capacitance detection accuracy of the CPAL sensor system, it is finally able to distinguish a 1% relative humidity change at 20%RH (corresponding to a 20 fF capacitance change, or a 1.63 dB output coefficient change), showing potential sensing application prospects.
Classification by VGG-Net for three stages of coagulation dynamic process
Authors: Li Yao , Li Wangbiao , Zhang Xiaoman , Lin Hui , Li Zhifang
Published: August 2024

In this study, we employed a method integrating Optical Coherence Tomography (OCT) with the Visual Geometry Group (VGG-Net) frameworks within a Convolutional Neural Network (CNN) for quantitative characterization of the whole blood during the dynamic coagulation process.
Advances in Electron-Based Qubits: A Review
Authors: Gao Zhuoqing , Amaratunga Gehan , Wang Xiaozhi , Ma Boyang
Published: August 2024

In the rapidly advancing domain of quantum computing, qubits based on electron properties are increasingly recognized for their capability to enhance quantum information processing and communications. This review offers a detailed examination of three main types of electron-based qubits: electron spin qubits, charge qubits, and hybrid qubits. Initially, the review outlines the essential principles underlying these qubits. Subsequently, it discusses recent developments in the field, focusing on enhancements in coherence times, logical gates, and system scalability. This article aims to provide both theoretical insights and practical recommendations for the development and refinement of quantum computing architectures.
A drop-shaped deterministic lateral displacement microfluidic chip for accurate size-based circulating tumor cells separation
Authors: Xiang Rikui , Chen Jin , Sun Jingjing , Huang Xiwei
Published: August 2024

Cells released from the primary tumor to the peripheral blood are referred to as circulating tumor cells (CTCs). The detection of CTCs at an early stage can be instructive to the implementation of follow-up treatments. However, due to the rarity of CTCs in the peripheral blood, it is urgent to develop an accurate CTC separation method. Here, we propose a drop-shaped deterministic lateral displacement (DLD) microfluidic chip to accurately separate and enumerate CTCs with cost-effective and simple testing procedures. The drop-shaped DLD enhanced performance for the separation of white blood cells (WBCs) and CTCs, which achieved CTCs high separation efficiency (>99%) and >50% CTCs purity. Our drop-shaped DLD microfluidic chip offers a label-free and highly reliable CTCs separation solution and is promising to low-cost point-of-care CTCs detection.
Salt-Enhanced Biocompatible Solid Polymer Electrolytes Humidity Sensor
Authors: Zhang Kaihang , Wu Jianhui
Published: August 2024

We present a biocompatible, ultrathin, porous freeze-drying Polyvinyl Alcohol/Hyaluronic Acid/Polylactic-co-glycolic acid/Magnesium Sulfate (FD-PHLM) composite-based high sensitivity humidity sensor, suitable for human interaction applications. Magnesium Sulfate was introduced to form solid polymer electrolytes and Electric Double Layer. The freeze-drying process produces a porous structure that leads to enhanced sensitivity and rapid responses (0.807 s response time, 0.683 s decay time) to humidity changes, with a sensitivity of 11.09 pF/%RH in the 10-90%RH range. The sensor utilizes materials that are non-toxic to both the human body and the environment, thereby expanding its application range to include contactless click sensing and exercise state sensing. The FD-PHLM sensor is a substantial innovation in humidity detection, combining biocompatibility, environmental friendliness, quick response time and enhanced sensitivity, aligning with the needs of human-centric environmental and health monitoring systems. This research contributes significantly to the development of efficient, environmentally friendly human activity monitoring tools.
An optimized MOPSA algorithm for highly accurate deterministic lateral displacement microfluidic sorting chip design
Authors: Chen Jin , Xiang Rikui , Huang Xiwei
Published: August 2024

Deterministic lateral displacement (DLD) sorting is a passive sorting technology. Due to the advantages of small volume and high accuracy, the DLD devices have been used in many applications. The critical diameter (Dc) value of the DLD device depends on the geometric structure of the internal post array. However, the existing empirical formula cannot match all types of post-arrays. Achieving the desired Dc value typically involves multiple iterative processes, leading to increased labor and time costs. In this paper, we propose an optimized trajectory prediction algorithm based on the original MOPSA, which considers the impact of fluidic pressure on particle trajectories. The method is to stretch the 2D physical field space into 3D, the particle expands from a 2D circle into a 3D ball on the pressure analysis. The net pressure on the particle is calculated, and the displacement of the particle is predicted by combining Newton’s second law and the displacement formula. A DLD device with Dc=10.6 μm was designed using this optimized algorithm and fabricated. It is verified by separation of 10 μm and 11 μm polystyrene particles. The test results were consistent with the simulation results. Compared with the empirical formula and the original MOPSA, this optimized algorithm can improve the prediction accuracy of particle trajectories in DLD devices.
The impact of the Island Layout on the Performance of the 4H-SiC Floating Island Device
Authors: Wang Ce , Wang Hengyu , Cheng Haoyuan , Wan Jiangbin , Zhang Chi , Li Yanjun , Makhdoom Shahid , Ren Na , Guo Qing , Sheng Kuang
Published: August 2024

The Floating Island (FI) structure in 4H-SiC device is able to break the “SiC 1D-Limit”. This is achieved by transforming the electric field distribution in the drift region from a single-triangle profile into a multiple-triangle profile, both of which have the same triangle height and width. With such an electric field distribution, the trade-off between breakdown voltage (BV) and specific ON-resistance (RON,sp) can be significantly improved. In this paper, the 4H-SiC FI Junction Barrier Schottky (JBS) diodes with four different island layouts, namely the stripe, the hexagon island, the hexagon hole and the hexagon cell, have been fabricated and tested. The results show that RON,sp is virtually the same at the same N-type area ratio, but BV diverges at the same N-type area ratio for different layouts. The stripe layout has the highest BV among the four island layouts. A BV of 2200V and RON,sp of 3.8mΩ.cm2 has been achieved with the stripe design.
Improving the performance of n-i-p perovskite photodetectors via bathocuproine electron transport interlayer
Authors: Zhao Lin , Lou Qiang , Chen Tong , Xu Jingyi , Zhou Hang
Published: August 2024

In this study, a planar photodetector with a n-i-p structure comprised of Glass/ITO/SnO2/bathocuproine (BCP)/Cs0.05(FA0.85MA0.15)0.95Pb(I0.85Br0.15)3/P3HT/Ag is investigated. Here, the BCP layer was inserted as a passivation layer between the SnO2 electron transport layer (ETL) and the perovskite to reduce the leakage current while improving its photodetectivity. As a result, the photodetector has a broad spectral response range (300-800 nm), and a low dark current of 8.20 × 10−7 A/cm2. In addition, the responsivity of the device reached 0.432 A W−1 when operated at self-powered mode, the corresponding detectivity reaches 7.4 × 1011 Jones, while the linear dynamic range reaches 51.3 dB and response time of 28 μs.
A high-responsivity 30 μm × 30 μm Perovskite-IGZO Phototransistor for Weak Light Detection
Authors: Hu Rundong , Lv Xueqing , Chen Tong , Lin Bosi , Zhou Hang
Published: August 2024

Introducing various absorption materials to the IGZO thin film transistor (TFT) forms new device approach for making high performance photodetectors and image sensors. In this study, a 30 μm × 30 μm IGZO phototransistor with quasi-2D perovskite absorption layer is demonstrated, which attains a high responsivity reaching 1.5 × 105 A W−1 and a well detectivity of 3.07 × 1014 Jones under 87.4 nW cm−2 illumination at 520nm. This approach combines the merits of low turn-off dark current of the IGZO TFT and the high optoelectronic properties of the perovskite photo absorption layer, which is very promising for forming high resolution low cost flat-panel image sensors.
Energy and exergy analysis of a hydrogen powered gas turbine operating in gas-steam system
Authors: Harutyunyan Artur , Badyda Krzysztof , Szablowski Łukasz
Published: August 2024

Due to the global climate strategy to reduce greenhouse gases and the energy crisis caused by global political and economic challenges, the development of renewable energy, as well as achieving energy security, has become a very urgent and priority issue for many countries of the world. As a renewable energy source hydrogen has a very high potential to consider a promising alternative fuel for the power generation, including gas turbines. Due to its high calorific value, low emissions and versatility, hydrogen has many advantages over conventional fuels. Also it is the fact that the gas turbine industry has made a strong commitment to developing gas turbines capable of operating with 100% hydrogen by 2030. And since gas turbines currently play a vital role in balancing the global energy system, expanding gas turbine fuel options to include hydrogen could increase their potential importance in both the energy transition and long-term energy strategies.

In recent years, most research and studies on hydrogen-fueled gas turbines, taking into account the ecological problem, have focused on the analysis of emission reduction in exhaust gases. Also, due to the difficulties of optimizing hydrogen combustion, most research and studies have concentrated on the analyzes of flame stability in gas turbine combustion chambers․ There are still many important questions that remain open and unexplored when it comes to energy and exergy analysis of hydrogen fueled gas turbines in simple and more complex systems.

In this paper, energy and exergy analizes of a hydrogen powered gas turbine in the gas-steam system was performed. The system consists of a gas turbine powered by methane blended with hydrogen at various compositions. The amount of hydrogen enrichment varies from 0 to 100% by volume. Implementation of such analyzes were done through mathematical models which had been built using Aspen HYSYS mathematical modeling program.
Heat transfer optimization via finned surface with the use of CFD
Authors: Drag Tomasz , Tokarski Mieszko
Published: August 2024

Finned tubes are widely used in many industries such as the automotive, petrochemical, refining, and energy industries. They are applied to increase heat transfer efficiency between fluids through the use of protruding fins on the outer or inner surface of the tube, which aim to increase the surface area of heat exchange. The efficiency of an externally finned tube made of copper is increased by maximizing heat transfer and minimizing costs using the Ansys package. Heat exchange efficiency is improved and production costs are lowered by optimizing finned tubes. Firstly, a finned pipe fragment was modeled and meshed. Then, heat exchange between hot free flowing air around the tube and cold water flowing through the pipe were simulated. The foundation width and fin length were optimized in the ranges of 0.38mm-3.63mm and 4.9mm-14.9mm, respectively, using the simulation as a base. After the optimization certain cases were calculated analytically. It was found that the thickness of the fin should be optimized regarding its impact on mass, and the length of the fin should be optimized regarding its impact on heat transfer. Additionally in straightforward cases, analytical results are similar to simulation results.
Improved heat transport and hydrogen sorption rate in the electric field aligned, graphite/magnesium hydride composites
Authors: Goc Kamil , Mineo Kentaro , Przewoźnik Janusz , Takasaki Akito , Kapusta Czeslaw
Published: August 2024

The results on the improvement of the heat transport and reaction rates in the magnesium hydride composite are reported. It has been achieved by admixing flake graphite and temperature proof silicone resin and, further, through their alignment with the applied strong electric field. The oriented, graphite-field composite samples show a 22-43% higher thermal conductivity, in comparison with isotropic samples, reaching values of 1.28 W/m·K. Improved heat transfer was found to increase reaction rates and the corresponding reaction times composites were shortened 54% and 40% min for absorption and desorption, respectively, which makes composites attractive for applications.
Brain CT to MRI medical image transformation based on U-Net
Authors: Liu Haoyang
Published: August 2024

Medical images are valuable resources for clinical diagnosis, each containing rich information about diseases. To fully utilize this information, it is crucial to achieve effective conversion between different types of medical images. This not only reduces the need for patients to undergo multiple imaging examinations but also helps to conserve valuable medical resources and reduce examination restrictions. Therefore, research on medical image transformation techniques is of significant importance, but it is also a highly challenging task. This study proposes an innovative medical image generation network based on the U-Net architecture, specifically targeting brain CT and MRI images. Through carefully designed preprocessing steps and pretraining strategies, the network in this paper can effectively convert brain CT images into MRI images, demonstrating significant performance on the SynthRAD2023 Grand Challenge dataset. Additionally, in clinical applications, MRI is favored for its high-resolution soft tissue imaging capabilities, while CT scans are known for providing high-resolution images quickly. However, the MRI scanning process is longer and may not be suitable for patients who cannot maintain specific positions for a long time. Therefore, the conversion technique between CT and MRI images plays a crucial role in improving the efficiency of medical image acquisition. The results of this study will enhance the work of converting CT to MRI images in clinical practice.
Divergent impacts of seasonal precipitation deficiency on grassland growth in drylands of Central Asia
Authors: Yuan Ye , Bao Anming , Chang Cun , Jiang Liangliang , Zheng Guoxiong , Yu Tao , Jiang Ping
Published: August 2024

Water availability and its timing are essential for determining dryland dynamics, and grasslands in Central Asia are particularly vulnerable to water provided by precipitation. Climate change is projected to alter the seasonal distribution of precipitation patterns and increase the frequency of extreme events. Little is known about the response of grasslands to seasonal precipitation deficiency (PD), especially considering the time lag effect. Here, we evaluated the impacts of PD on grassland growth at the seasonal scale based on the normalized difference vegetation index (NDVI). Our findings showed that grassland growth during spring was mostly affected by PD in arid regions, with PD occurring during the nongrowing season and spring causing mean standardized anomalies (SAs) of −0.83 and −0.54, respectively, for the NDVI. In semiarid and subhumid regions, summer PD caused not only the largest negative response in summer (with SAs of −0.94 and −0.80 for semiarid and subhumid regions, respectively) but also in autumn (−0.80 and −0.74). PD in autumn had a less adverse effect on grassland growth. The divergent seasonal responses primarily stemmed from shifts in the dominant factors influencing grassland growth across seasons. PD reduced soil moisture in spring and summer, which in turn affected grassland growth. However, summer PD affected autumn grassland growth primarily through the carryover effect. Our results highlighted the importance of the timing of PD and suggested that precipitation in the previous season should receive more attention when considering the relationship between vegetation and precipitation at the seasonal scale.
Evaluation of The Performance of Enzyme-Induced Calcite Precipitations (EICP) Solutions Based on pH and Electrical Conductivity
Authors: Ali Mustafa S. , Almurshedi Alaa D. , Karkush Mahdi
Published: August 2024

EICP is an innovative, sustainable technology that utilizes specific chemicals, particularly urea and calcium chloride, in conjunction with the urease enzyme to induce the precipitation of calcium carbonate. The abovementioned technology is widely acknowledged as contemporary and environmentally responsible, aligning with established sustainability principles and green construction criteria. The quantity of precipitated calcium carbonate is contingent upon the composition of the materials employed in the precipitation process and their respective proportions. The investigation focused on determining the best percentage of calcium carbonate precipitation by conducting experiments on different concentrations of urea, calcium chloride, and the urease enzyme and examining the specific characteristics of the chemical solution that facilitate the precipitation process. The augmentation of urea and calcium chloride to a certain proportion resulted in a corresponding augmentation in the quantity of precipitated substances such as calcium carbonate. In the course of furthering the increase process, it was observed that the value of the precipitated materials remained constant and did not exhibit any further augmentation for some mixing ratios. According to the results of current study, the best ratio to precipitated calcium carbonate can be attributed to using an optimal ratio of 1 mol/L of urea and 0.5 mol/L of calcium chloride. Due to the notable efficacy of urease, the concentration increment of urease did not exhibit significant variation beyond 1 g/l. However, the alteration in the rate of reaction velocity will influence the outcome of EICP process. The experimental results and integration of several methodologies demonstrated a positive correlation between temperature elevation and reaction rate augmentation, resulting in a rapid reaction termination.
Shear Strength and Collapsibility of Gypseous Soil Improved by Nanomaterials
Authors: Emad Rafal , Salman Alaa D.
Published: August 2024

The current research focuses on studying the effect of nanomaterials (nano clay and nano-metakaolin) on the collapsibility and shear strength of gypseous soils before and after soaking. This study also addresses the effect of nanomaterials on physical properties such as specific gravity, soil density, and permeability of gypseous soils. A sample of gypseous soils obtained from the city of Tikrit, which is located 200 km north of Baghdad, and which contains 54% gypsum content. Gypseous soil samples were mixed with three percentages of nanomaterials (1, 2, and 3) % calculated on the basis of the dry weight of the soil to measure their effect on the geotechnical properties of the soil samples. The probability of collapse of gypseous soil decreases with increasing nanomaterial content. The shear strength also increases with increasing nanomaterial content and increasing curing period
Experimental Investigation on Effect of Cementitious Materials on Strength of Sandy Soils
Authors: Abbas Kareem Ammar , Shaban Alaa M
Published: August 2024

Weak soil characteristics pose a significant challenge for geotechnical engineers when designing the foundations of a structure. Consequently, researchers resort to improving the properties of weak sandy soil by mixing it with pozzolanic or chemical additives. This study aims to assess the effects of using cementitious materials to enhance the strength and stiffness of loose sand soils. To achieve this goal, experimental work was conducted, involving several laboratory tests to determine the soil properties. Three different curing times were utilized (one day, three days, and seven days), and four various percentages of the added cementitious material were employed (5%, 10%, 15%, and 20%) as a replacement by the weight of the treated soil. The results revealed that 15% is optimum gp content must be added to the mixture for optimum strength and stiffness. And three days is the optimum curing time.
Simulation and Evaluating of Traffic Flow for Hillah City Using VISSIM and GIS Programs
Authors: Flaah Wurood , Ajam Harith K K
Published: August 2024

The transportation network is crucial for modern society, with roads being essential for passenger and goods transportation. Al-Hillah, a highly congested center in Babylon province, experiences congestion due to its strategic location as a major transit route and the presence of vitality centers like education, commerce, and government. The main goals of this study are to evaluate the service level of the current traffic situation on the road network using the VISSIM software and to know the extent of the network’s connectivity using the GIS program. The whole length of the Hillah Road network as well as the number of nodes and linkages are among the data collected. These links represent major and minor arterials and vehicle movement surveys, both external and internal, from the center city for peak periods, vehicle classification, and geometric characteristics for each link and node in the network. Then a collection of parameters was computed for assessing the road network, which is considered one of the quantitative indicators used to measure network connectivity, such as
β
the index,
α
the index,
γ
the index and
η
the index. The results showed that the study sites operate with a high level of service LOS (F), and on the basis of this, some improvements were suggested to improve the level of service and reduce congestion.
Bioremediation of contaminated soil by crude oil of Baiji refinery by extraction of the local dominant bacteria
Authors: Ahmed Rand R. , Al-Obaidi Ahmed A. , Mohammed Zainab Bahaa
Published: August 2024

In most communities, soil contamination is a problem as it affects people and the environment. Because oil spills on soil substantially impact the environment, accidental infusions and spills of ore oils frequently result in a complete or partial exchange of the soil pore fluid by oil-contaminated soils, altering the geotechnical engineering characteristics. Therefore, efficiently removing petroleum hydrocarbon pollutants from contaminated soil is urgently needed. A novel technique that is gaining popularity worldwide to clean up places polluted with petroleum hydrocarbons is known as bioremediation. This study browser the fundamental processes involved in bioremediation and removal efficiency of TPH (Total Petroleum Hydrocarbon) within different periods for (the Baiji refinery) which is polluted with crude oil as a result of numerous oil wells, oil drilling, pipeline, and storage tank damage, natural seepage, and spills during the conflict and Noory channel which content crude oil, waste of refinery process and sludge. The research aims to extract the dominant bacteria in the contaminated soil and use the last in bioremediation and find out the differences in its effectiveness in treating total petroleum hydrocarbons (TPH) later. The result indicates that the dominant bacteria are Stutzerimonas balearica and Bacillus subtilis which are used later in bioremediation and can digest TPH. The removal efficiency of TPH during the study period was 55, 65, 68, 78, 82, 85, and 92% for spilled samples and 50, 62, 66, 70, 80, 84, and 90% for the Noory channel, respectively.
Effective Use of Pozzolanic Materials for Stabilizing Expansive Soils: A Review
Authors: Ali Lina H. , Atemimi Yahya K.
Published: August 2024

Soils have a detrimental impact on engineered structures, such as pavements and foundations, are often referred to as problematic or challenging soils. These soils encompass various types, including but not limited to the expansive soil, the damage arises from inadequate or unfavorable engineering characteristics, including low shear strength, excessive compressibility, and substantial volume alterations. Expansive soils, in particular, pose a considerable challenge due to their susceptibility to the shrink-swell phenomenon when interacting with water. Addressing these challenges requires implementing various soil treatment or stabilization techniques, including mechanical and chemical techniques. The decontamination techniques that incorporate sustainability principles receive preference for their use of environmentally friendly materials and their attempts to reduce the consumption of natural resources. Pozzolanic materials have been meticulously selected in this comprehensive analysis for discussion and thorough consideration as effective chemical stabilizers. The chosen pozzolanic materials encompass a range of options, including agricultural waste, conceptual waste, industrial, and byproducts. These options may include ashes derived from agricultural waste and various types of calcined clay. A wide array of materials in civil engineering contributes to the construction process. These materials comprise egg ash, sugarcane straw ash, rice husk ash, silica fume, fly ash, blast furnace slag, cement, and lime. In a broader context, using pozzolanic materials to stabilize expansive soils is crucial in mitigating swelling and Atterberg’s limits while enhancing compaction and strength parameters. Nevertheless, it is essential to acknowledge the wide range of percentages associated with the use of pozzolanic materials as stabilizing agents.
The behavior of geogrid-reinforced sand soil supporting shallow footing under earthquake
Authors: Al-khafaji Ruqayah , Mohammed Shafiqu Qassun S.
Published: August 2024

Earthquakes are detrimental phenomena that can result in significant loss of lives and infrastructures. During earthquakes, shallow foundations can suffer considerable settlement, tilting, and sliding resulting in foundation failure. One of the promoting techniques that can enhance soil performance is soil reinforcement using geogrid. Until recently, there are very limited studies that concern with the response of the square foundation when founded on geogrid-reinforced soil. This study aims to examine the influence of square footing founded on sand soil with and without geogrid reinforcement under the 2017 Halabjah earthquake using a shaking table system. The soil was prepared with relative density of 30% with and without reinforcement. The sand was reinforced with one, two and three layers of geogrid type InterAx NX750 supplied by Tensar Company. The first layer of geogrid was placed at depth of 0.3B, the distance between the geogrid layers was 0.3B, and the length of the geogrid is 4B (B: footing width). The shaking table used in the study was fabricated locally. The settlement and horizontal displacement, tilting, acceleration and pore pressure were measured using a rope displacement sensor, tilt sensor, accelerometers and pore pressure transducers respectively. The results showed that the use of geogrid reinforcement can enhance the soil behavior by decrease the foundation settlement and displacement, and minimize the tilting of the footing. The highest decrease in the settlement and titling of the footing was given by the soil reinforced with three layers of geogrid. The results also showed that reinforcement decreases the amplification of the acceleration. In addition to the decrease in the pore pressure developed in the saturated sand soil and in consequence decreases the liquefaction ratio (Ru). Nevertheless, the influence of the geogrid reinforcement on the liquefaction ratio and acceleration are lower than that of settlement, and tilting.
The use of lime and Nano CaCo3 to controlling on collapsibility of gypsiferous soils
Authors: Al-khafaji Sarah Ahmed , Al-Janabi Ahmed Talib
Published: August 2024

Gypsiferous soils, or gypsic minerals, are soils with a high proportion of sulfate calcium sulphate, typically form in areas with high rates of evaporation and little to no rainfall. These soils are distinguished by a gypsiferous deposit of over 5% in the top meter of the soil profile, thick surface crust, salinity, and sodality. The term “gypseous soil” refers to the predominant calcium-sulfate compound in soil composition. The research’s soil samples came from two locations of Karbala governorate at the Ain Al-Tamr area and at Shabas Salman area. These soils had gypsum content of 51% and 2% respectively. In this research, an experimental investigation is performed on the influence of two different additions to the gypseous soil in order to reduce the collapse potential of the these soil using the Single Odometer Test (SOT) method. This study’s additives were lime and a mixture of lime and CaCo3 nanoparticles. The percentages of lime were 4% and 8%, but the percentage of CaCO3 nanoparticles replaced each of the stated ratios of lime by 0.25, 0.5, and 1% of CaCO3 nanoparticles. Testing was also done on the soils in their natural form to see how additions affected them. Although the primitive proportions of these additives contributed to reducing the collapse potential of these soils, they remained within the unsafe classification until reaching the optimal ratio of treatment according to the treatments used in this research, where they were (3% lime + 1% CaCO3 nano) or (7.5% lime + 0.5% CaCO3 nano) for soil I. As for soil II, the optimal treatment ratios were (3.5% lime + 0.5% CaCO3 nano), (3% lime + 1 CaCO3 nano), (7.25% lime + 0.25 CaCO3 nano), or (7% lime + 1% CaCO3 nano). To a certain extent, the treatment becomes useless and can result in a reverse process, that is, the probability of collapse returning to increase again.
Glass waste impact on the rheological characteristics of field soil of Kirkuk city, Iraq
Authors: Ali Serwa Q. , Raheem Aram M. , Omar Najat Q. , Naser Ibrahim J.
Published: August 2024

Environmental awareness has forced the need for extensive studies to explore environmentally benign and locally available materials in soil improvement and stabilization processes. Since one of the most important main rheological properties is the apparent viscosity, it was necessary to study it. In this paper, the rheological properties such as the apparent viscosity and the yield point of the soil of four sites in the city of Kirkuk were studied without and with proportions of the additive that was chosen in this study, which is glass waste powder. Passing through sieve No. 200 is due to its ability to bear costs and reduce pollution by reducing solid waste. Rheological tests were conducted for each soil sample after passing through a No. 200 (0.075 mm) sieve, and the viscosity, yield point and gel strength were evaluated at different speeds using a viscometer in the laboratory. The mixture consisted of 25 grams of soil and 350 milliliters of water and was compared with mixtures containing different percentages of glass waste powder (6, 10, and 20% by weight of dry soil). It was found that the apparent viscosity of the first point had the highest value in the soil treated with 20% glass powder, and its value was 1.3 cm, meaning the viscosity increased by 62.5%. The yield points also reached its maximum at 10% glass powder, which is equivalent to 1 Ib/100 square feet, and the apparent viscosity at the second point was maximum at the ratios of 6% and 10%, and its values were 1.3 cp, meaning the viscosity increased by 116.7%. The maximum value of its yield point was at 0% glass powder, with a value of Ib/1001.1. As for the apparent viscosity of the third point, it had the highest value in the soil treated with 10% glass powder, and its value was 1.4 centimeters, meaning the viscosity increased by 180%. The yield points also reached its maximum at 0% glass powder, which is equivalent to 1 Ib/100 square feet. As for the apparent viscosity of the fourth point, it had the highest value in the soil treated with 20% glass powder, and its value was 1.2 centimeters, meaning the viscosity increased by 140%. The yield point reached its maximum at 0% glass powder, equivalent to 1Ib/100 sq. ft. In addition, shear stress versus shear stress rate for untreated and glass-treated field soils was modelled using four different models including capacity models, Bingham models, Herschel-Bulkley, and hyperbolic models where it was shown that the hyperbolic model was the best in predicting shear stress versus shear strain rate with the highest R2 of 0.992 and the lowest RMSE of 0.083 Pa.
Diagnosis of risk factors that lead to serious casualties in the road construction projects in Iraq
Authors: Makki Dishar Marwa , Altaie Meervat R.
Published: August 2024

Projects involving the implementation of roads are considered to be among the most hazardous endeavors. Although preventing accidents is challenging, there are ways to make them less likely. Therefore, it is necessary to diagnose most common accidents that workers in these projects are exposed to. The study was conducted in Iraq through a questionnaire to collect data from experts and engineers specialized in the subject of the study. The questionnaire included six main factors and forty-two sub-factors causing accidents in road projects in Iraq amassed from prior research and hands-on experience. “A relative important Index (RII)” was utilized to establish the relevance of each sub-factor. This study found that human, construction site, mechanism, and excavation variables cause Iraq’s most common road implementation accidents. This study found 22 influential subfactors. Identifying these factors helps decision-makers to develop plans and take the necessary measures to reduce future accidents affecting workers in road projects in Iraq, as well as to make practical decisions that ensure the safety of workers in these projects.