Contraction Stress Research Articles

Naturally Inspired Tree-Ring Structured Dressing Provides Sustained Wound Tightening and Accelerates Closure.

Mechanically regulated wound dressings require a rational combination of contraction and adhesion functions as well as balancing exudate-induced swelling issues. However, many of the reported dressings face the dilemma of impaired function and impeded wound self-contraction due to fluid-absorbing swelling. In this study, inspired by the tree ring, a core-ring structured hydrogel dressing capable of mechanical modulation is designed, and prepare it using a simple two-step photopolymerization process. The core covers the center of the wound, contracts spontaneously at body temperature to generate a contractile force of 3.4kPa, and resists swelling. Meanwhile, the ring adheres to the normal epidermis around the wound and transfers the contraction stress to the wound edge. The integration of a functionally independent core and ring ultimately achieves effective wound traction and avoids dressing swelling. In murine and porcine skin wound-healing models, this hydrogel with a closely connected core and ring promotes healing by accelerating epidermal closure (50% closure in mouse skin on day 2, 85% closure in pig skin on day 8), collagen deposition, vascular maturation, and extracellular matrix remodeling. These results can guide further research on mechanical force modulation in wound healing, with the potential for clinical translation.

Study on the mechanism of laser-induced breakdown and damage performance of internal defects in transparent materials through local optical field modulation

This paper establishes a photothermal damage model for bubble impurities affecting laser optical field modulation based on Mie scattering theory and incorporates the effects of optical field modulation. This model elucidates the evolution mechanism of synergistic damage in fused silica, with simulation results validated through experimental verification. A novel characterization of optical breakdown due to bubble impurities is proposed, occurring on a millisecond timescale through the dynamic evolution of combustion waves. The model delineates the influence of bubble size and spacing on optical field distribution, temperature, stress distribution, and their evolutionary behaviors. The modulation of the optical field due to double bubble impurities creates a localized “hot spot,” resulting in a differential transverse contraction stress at the edges of the bubble impurities, thereby reducing the damage threshold of fused silica. The spacing of 1.1 λ represents the enhancement node for optical field modulation by double bubble impurities. Furthermore, localized oscillations in the optical field arise when the spacing between the double bubbles exceeds 1.1 λ, attributed to changes in the refractive index at the bubble defects and resonance oscillations generated by optical field modulation. This study not only enhances our understanding of the optical field modulation processes occurring at 1064 nm in the presence of bubble defects but also establishes a theoretical foundation for detecting internal defects at this wavelength without inducing surface damage.

Evaluating the effects of cement asphalt emulsion paste as a grouting material on the fatigue and thermal contraction properties of semi-flexible asphalt composite pavement

Semi-flexible asphalt (SFA) composite pavement is widely used in pavement engineering for its high load-bearing capacity, enhanced durability, impermeability, and resistance to fuel and oil spillage. However, its cracking resistance remains a concern, influenced by repeated vehicle loads and thermal contraction stresses. This study investigates the impact of cement asphalt emulsion paste as a grouting material on SFA’s fatigue and thermal contraction. SFA specimens were grouted with cement paste (CP) containing 20%, 40%, and 60% asphalt emulsion. These specimens were subjected to indirect tensile strength, resilient modulus, and fatigue tests, along with evaluation of thermal contraction behavior using coefficient of thermal contraction. Results indicated that adding asphalt emulsion to CP enhances the flexibility and ductility of SFA but reduces its indirect tensile strength and stiffness modulus. A mathematical model was introduced to predict the resilient modulus based on indirect tensile strength tests. The fatigue analysis demonstrated significant difference in fatigue resistance between SFA and AC16 materials. Incorporating asphalt emulsion also improved SFA’s thermal contraction behavior.

Nanoscopic Insights into the Collapse of Metal-Organic Frameworks during Solvent Evacuation: Molecular Simulation Investigation.

Many metal-organic frameworks (MOFs) undergo structural collapse upon solvent evacuation during activation, which is attributed to the capillary force generated by the solvent. However, little effort has been devoted to unveiling the nature of such a force. Herein, we employ molecular dynamics (MD) simulations to investigate the evacuation of different solvents in two MOFs (MOF-5 and UMCM-9). The contractive stress induced by solvent evacuation is quantified and unraveled to positively correlate with the surface tension of the solvent. Moreover, the mechanical strength (or amorphization) of the MOF is calculated using reactive MD simulations. By comparing the contractive stress with the amorphization stress, for the first time, we predict the likelihood of collapse of MOFs during activation by different solvents, which agrees well with the experiments. The methodology developed provides nanoscopic insights into the activation process; it can assist in avoiding structural collapse by judiciously selecting a proper solvent for activation or by modifying a framework.

Understanding a new wrinkling behavior of annular grooved panel during flexible free incremental sheet forming

Wrinkling behavior of sheet metal by inappropriate process parameters and the resultant variation of thickness and microstructure during incremental sheet forming (ISF) have significant impact on forming stability and geometric profile. The wrinkling-related mechanism is yet to be well understood, which make it difficult to effectively control wrinkling defects during ISF. In the present work, the wrinkling behavior and related mechanism of a typical annular grooved panel are investigated during a novel flexible free ISF process. Experiments demonstrate that during this ISF process, the sheet material sequentially undergoes 4 deformation modes: contacting state under plane strain condition, contracting state with only elastic deflection, thickening state under uniaxial compression condition, and wrinkling state where the circumferential compressive stress exceeds the critical wrinkling stress. The evolution of these deformation modes is dominantly caused by the increasing of edge contraction and circumferential stress, which are induced by the bending moment from the forming tool and auxiliary sheets. Based on the mechanism, an analytical model is developed to predict the wrinkling behavior, by which the corresponded sheet thickness, bending moment, circumferential compressive stress and critical wrinkling stress during the wrinkling process could be comprehensively calculated. Experimental results validate that the analytical model can accurately predict the wrinkling behavior under different process parameters, material properties and auxiliary sheet materials. Through microstructural characterization, numerical simulation and analytical modeling, the influence of process parameter and material property on wrinkling behavior is systematically investigated, along with the variation of sheet thickness and microstructure under different wrinkling modes. This work enhance a deep understanding of wrinkling behavior during ISF process, thereby providing effective methods for process optimization and quality improvement.

Optogenetic induction of mechanical muscle stress identifies myosin regulatory ubiquitin ligase NHL-1 in C. elegans

Mechanical stress during muscle contraction is a constant threat to proteome integrity. However, there is a lack of experimental systems to identify critical proteostasis regulators under mechanical stress conditions. Here, we present the transgenic Caenorhabditis elegans model OptIMMuS (Optogenetic Induction of Mechanical Muscle Stress) to study changes in the proteostasis network associated with mechanical forces. Repeated blue light exposure of a muscle-expressed Chlamydomonas rheinhardii channelrhodopsin-2 variant results in sustained muscle contraction and mechanical stress. Using OptIMMuS, combined with proximity labeling and mass spectrometry, we identify regulators that cooperate with the myosin-directed chaperone UNC-45 in muscle proteostasis. One of these is the TRIM E3 ligase NHL-1, which interacts with UNC-45 and muscle myosin in genetic epistasis and co-immunoprecipitation experiments. We provide evidence that the ubiquitylation activity of NHL-1 regulates myosin levels and functionality under mechanical stress. In the future, OptIMMuS will help to identify muscle-specific proteostasis regulators of therapeutic relevance.

Release of contraction stress of dental resin composites by water sorption

Polymerization shrinkage of bonded resin composite restorations will result in the development of curing contraction stresses during setting and can cause debonding of the restoration or failure of the surrounding tooth structure. However, the hygroscopic expansion that occurs after exposure of the restorative to the wet oral environment can compensate for this shrinkage. ObjectivesThe purpose of this study was to determine the hygroscopic expansion of six commercial resin composites and relate it to their composition, mechanical properties, shrinkage, and contraction stress development. MethodsShort-term volumetric shrinkage and contraction stress of the different composites were measured by mercury dilatometry and a universal testing machine. The long-term contraction stress was measured by the deflection of a bilayer strip of metal and a resin composite, which were stored dry as well as wet to determine the effect of hygroscopic expansion. The curvature of the strip was measured by profilometry over a period of 3 months. ResultsThe curvature of the strip correlated well (r2 =0.74) with the initial contraction stress, showing that the contraction stress is an important factor in initial deformation. The water sorption in all specimens showed that the initial deformation, within 2–4 weeks after curing, was completely counteracted. A high correlation (r2 =0.90) between deflection and relative water sorption was found, where the relative water sorption is defined as the absolute water sorption corrected for the inorganic filler volume of the composite. SignificanceWithin a period of 2–4 weeks after curing most of the curing contraction stresses of resin composite restoratives will be released by hygroscopic expansion.

Lattice contraction and Surface stress investigation in nanoparticles of zinc sulfide

Nanostructured zinc sulfide was synthesized through controlled chemical precipitation method using zinc chloride and sodium sulfide as starting materials. Zinc sulfide nanoparticle with different average grain sizes were obtained by annealing the as prepared sample at different temperatures in inert atmosphere. The samples were characterized using XRD, TEM, and SAED. The lattice contraction, which have significant impact on the electrical and mechanical properties of nanomaterials were studied using Hall-Williamsons analysis. The lattice contraction present in nanoparticles of zinc sulfide with different average particle size at different planes was studied. The observed lattice contraction in nanoparticles of zinc sulfide seems to have contributions from micro strain over and above the contribution from quantum confinement effect due to small particle size and it follows an inverse proportional relationship with the particle size.The present paper discusses the reduced unit cell size in ZnS nanoparticles, along with their diminutive particle size, and its contribution to the broadening of X-ray diffraction peaks.

Oxidative damage and cardiotoxicity induced by 2-aminobenzothiazole in zebrafish (Danio rerio)

There is limited information available on cardiovascular toxicity of 2-Aminobenzothiazole (NTH), a derivative of benzothiazole (BTH) commonly used in tire production, in aquatic organisms. In the present study, the zebrafish embryos were exposed to varying concentrations of NTH (0, 0.05, 0.5, and 5 mg/L) until adulthood and the potential cardiovascular toxicity was assessed. NTH exposure resulted in striking aberrations in cardiac development, including heart looping failure and interference with atrioventricular canal differentiation. RNA-sequencing analysis indicated that NTH causes oxidative damage to the heart via ferroptosis, leading to oxygen supply disruption, cardiac malformation, and ultimately, zebrafish death. Quantitative real-time polymerase chain reaction (qPCR) analysis demonstrated the dysregulation of genes associated with early heart development, contraction, and oxidative stress. Additionally, reactive oxygen species accumulation and glutathione/malondialdehyde levels changes suggested a potential link between cardiac developmental toxicity and oxidative stress. In adult zebrafish, NTH exposure led to ventricular enlargement, decreased heart rate, reduced blood flow, and prolonged RR, QRS, and QTc intervals. To the best of our knowledge, this study is the first to provide evidence of cardiac toxicity and the adverse effects of ontogenetic NTH exposure in zebrafish, revealing the underlying toxic mechanisms connected with oxidative stress damage. These findings may provide crucial insights into the environmental risks associated with NTH and other BTHs.

Dual-outward contraction-induced construction of 2D hollow carbon superstructures.

A novel dual-outward contraction mechanism is applied to construct 2D hollow carbon superstructures (HCSs) via pyrolysis of hybrid ZIF superstructures. One outward contraction stress is offered by the in situ formed thin carbon shell, while another originates from the interconnected facets of ZIF polyhedra within the ZIF superstructure.

Mechanisms of Heat-Treatment-Induced Cracking in Additively Manufactured IN738 Alloy

The present study conducts a comprehensive study on heat-treatment-induced cracking of Inconel 738 (IN738) alloy fabricated by laser powder bed fusion (LPBF) using scanning electron microscopy (SEM), energy dispersion spectrum (EDS), and electron backscatter diffraction (EBSD). The results indicate that the macroscopic crack is dominantly triggered by the strain-age cracking mechanism and propagates along grain boundaries. The initiation of cracking is facilitated by the superimposition of residual stress induced by the LPBF process and contraction stress induced by precipitation, while the reopening of compress pores at grain boundaries weakens the grain boundaries and provides fast channels for cracking. These results revealed the coupling effects in triggering heat-treatment-induced cracking, offering a fundamental guideline for crack control during heat treatment of additively manufactured IN738 alloy.

Designing a 3D structure and a self‐healing technique for advanced polymer composites with outstanding mechanical properties and healing ability

AbstractWe designed three‐dimensional (3D) structures through a combination of glass fiber cloth and in situ formation of nano polyphenylene oxide (PPE) fibers during the fabrication process of thermosetting cyanate ester/bismaleimide composites and developed a self‐stitching technique based on PPE fiber and interpenetrating polymer networks (IPNs) for aiding the crack self‐healing. The building of 3D structure effectively improves the interface interaction between fiber and matrix and suppresses the crack propagation process in composite, leading to significant enhancement in the mechanical properties. When PPE content is 20%, the interlaminar shear strength, flexural strength, impact strength, and tensile strength of the resulting composite are 98%, 74%, 95%, and 101% higher than those of the composite without PPE. The resulting composites possess excellent thermomechanical and lower dielectric properties. Because IPNs within composites can create interspaces and easily deform above glass‐transition temperature, PPE components may penetrate through the interspaces under thermal expansion force, and the contraction stresses of polymers generate strong locking effects in composite after cooling to room temperature, then the crack surfaces of composites can be stitched by PPE fibers, significantly recovering the mechanical properties. The healing efficiency of the composite with 30% PPE after impact and then heating at approximately 280°C can reach 96%.Highlights 3D structures were constructed during the fabrication process of glass‐fiber‐reinforced thermosetting cyanate ester/bismaleimide composite. A self‐stitching technique was developed for aiding the crack self‐healing of composite. 3D structures significantly improved the interface interaction between fiber and matrix in laminated composite. The mechanical properties of the resulting composite could be significantly improved by 3D structures. The healing efficiency of the healed composite could reach 96%.

Generation and origin of persistent high excess pore water pressure in debris flows

Due to building up excess water pressure, debris flows differ markedly from other water-sediment mixtures in mountain basins. Although a number of mechanisms are known to create excess water pressure, persistent high excess water pressure develops in static-quasistatic debris-flow slurries when possible triggers such as saturation, contraction, and Reynolds stress are absent. This suggests that there exist more fundamental mechanisms for the creation and persistence of high excess water pressure. Using 12 clastic materials with four maximum diameters up to 40 mm from three typical debris flows in Southwest China, we make comparative measurements of excess water pressure, gravity drainage, and decanting of water on 12 pairs of debris-water mixtures. It is found that saturation is not a mechanism for excess water pressure generation, which can be ascribed to the heterogeneity of saturated sediments. Mixing undoubtedly creates persistent high excess water pressure in the mixed saturated sediments. Thorough mixing causes the homogenization of water-saturated sediments through random grain rearrangements. The particles in the homogeneous debris-water mixtures stay suspended in water, resulting in excess water pressure derived from particle weight. More significant is the integration of clasts and water over the timescales for debris-flow durations promoted by mixing, which leads to the persistence of high excess water pressure. The development of persistent high excess water pressure in sediment-water mixtures is controlled by external factor—mixing, and internal factors, including sorting of sediments and water content of mixtures.

Optimization of Accurate Spacing for Gas Extraction from Damaged Coal Seams Based on a Dual-Penetration Model

In order to develop precise hole placement technology for gas extraction, this paper combines industrial testing, the evolution law of coal rock damage permeability, and the coal double-pore double-permeability model; establishes a coupling model of the coal damage deformation field and matrix-fracture double diffusion seepage field; and determines precise hole placement spacing for a coal seam gas by using the COMSOL Multiphysics 5.6 numerical simulation software. This study shows that the effective radius of gas extraction is 4.8 m after 180 d of extraction, which is a power function of the extraction time. The permeability of the coal body is affected by matrix adsorption, and contraction and effective stress, and the influence range between the boreholes under multi-hole extraction increases with the increase in spacing; at the same time, we took into account the positive effect of the permeability change on the extraction effect and ultimately determined the optimal spacing of boreholes in Dashucun Mine to be 6 m, which was arranged in the square area. The extraction effect was good after the on-site test, and the results of this study can provide guidance for the optimal arrangement of the spacing of boreholes in the underground areas of coal mines.

Labor Induction in Case of Fetal Growth Restriction (FGR)

Clinicians consider a range of variables when formulating decisions regarding the diagnosis, monitoring plan, and ultimately the decision to recommend the delivery of a growth-restricted fetus. The differential diagnosis of a pathological fetal growth pattern is initially considered via the history, a physical and laboratory examination of the pregnant person, as well as a comprehensive fetal ultrasound examination. These factors allow a broad distinction between pre-existing disease in the pregnant person, constitutionally small normal growth, placenta-mediated Fetal Growth Restriction (FGR), and intrinsic fetal disease. Most commonly, pathological growth restriction is mediated by underlying placental diseases, of which maternal vascular malperfusion is the most common, and often results in co-existent hypertension. A program of combined monitoring of the pregnant person and fetus, comprising hypertension assessment, and serial fetal ultrasound, including Doppler studies is then instituted, and may be combined with biochemical markers, such as Placental Growth Factor, for greater clinical precision. Recommendations on timing to deliver the growth-restricted fetus worldwide are converging, with similar guidance from clinical practice guidelines informed by high-quality Randomized Controlled Trials (RCTs) and large cohort studies. In most instances, it is reasonable to recommend delivery of all growth-restricted fetuses by approximately 38 weeks. Timing of delivery should take into consideration both short-term neonatal outcomes and long-term outcomes at school age. Mode of delivery is based on many factors, and induction of labor is a safe approach, especially after 34 weeks. Mechanical methods of induction may be preferred to pharmacologic methods, although both have a role and the choice of method is based on individualized assessment. Elective Cesarean birth thereby bypassing fetal stress during labor, is recommended in preterm growth-restricted fetuses with signs of adaptive fetal compromise, especially when ductus venosus flow is abnormal, or a contraction stress test is positive.

Clinical and Diagnostic Clues for the Approach of Patients with Suspected Acute Aortic Dissection

Aortic dissection is a rare condition that frequently manifests suddenly as a catastrophic sickness with intense back or chest pain that is ripping, along with acute hemodynamic compromise. For survival, early and precise diagnosis and treatment are essential. An urgent need for heart surgery is acute ascending thoracic aortic dissection. In stable patients, acute descending thoracic aortic dissection is treated medically, but endovascular interventions may be needed if persistent pain, dissection progression and end-organ ischemia. Acute medical management includes pain control and anti-impulse therapy to reduce the velocity of LV contraction and decrease shear stress by giving antihypertensive therapy (target BP 100 to 120mmHg) typically using IV beta blockers with a target HR of less than 60.

An In vitro Comparative Evaluation of the Fracture Resistance of Teeth with Mesio-Occluso-Distal Preparations Restored with Different Esthetic Materials by Bulk-Fill and Incremental Methods

Introduction: One of the most popular restorative materials today is resin-based composite. Volumetric shrinkage is brought on by polymerization, which can cause contraction stress, microleakage, and adhesion failure. Adhesive restorations have several benefits, including the ability to preserve more healthy tissue and “reinforce” the remaining tooth structure. These benefits go beyond just being attractive. Materials and Methods: Eighty extracted human maxillary premolars were entrenched in a self-cured acrylic resin in a rubber mold cylinder (2.5 cm width-3 cm height). These were arbitrarily divided into 5 groups: 2 control groups (positive control group and negative control group) (n = 10) and 3 experimental (n = 20) groups (microhybrid composite, nanocomposite, and Giomer). The mesio-occluso-distal (MOD) cavities were prepared in 70 samples. After MOD cavities preparation, groups were further subdivided into two subgroups for bulk-fill and incremental methods. Universal Tofflemire Retainer and band were placed on the prepared cavities. The self-etch adhesive was applied on all aspects of the preparations and then it was light-cured using a light-curing unit for 15 s. Now, cavities were restored with different esthetic materials and methods. In the bulk-fill method, the MOD cavity was restored with a solitary increase of restorative material and light cured from all directions of tooth for 20 s each. In the incremental technique, the proximal box on both sides was reconstructed first in a gradual manner, in which two oblique increments and one horizontal increment were restored and treated for 20 s. Then, two oblique increments of material were used to reestablish the occlusal component, and it was once more light-cured for 20 s. Fracture resistance was checked using a steel bar with a diameter of 4.5 mm that was positioned in the middle of the occlusal surface and a crosshead speed of 3 mm/min, all of the samples were compressed axially loaded. Results: The fracture resistance of microhybrid composite resins in bulk technique was significantly higher than that of nanocomposites and Giomer. However, the fracture resistance of nanocomposite in the incremental method was significantly higher than the other two restorative materials. Conclusion: The quality of restoration depends both on the material and method used during the restoration procedure. Both factors are dependent on each other. Superior fracture resistance was shown by microhybrid composites when restored with the bulk-fill technique and nanohybrid composites when restored with the incremental technique.

Stiffness sensing by smooth muscle cells: Continuum mechanics modeling of the acto-myosin role

Aortic smooth muscle cells (SMCs) play a vital role in maintaining homeostasis in the aorta by sensing and responding to mechanical stimuli. However, the mechanisms that underlie the ability of SMCs to sense and respond to stiffness change in their environment are still partially unclear. In this study, we focus on the role of acto-myosin contractility in stiffness sensing and introduce a novel continuum mechanics approach based on the principles of thermal strains. Each stress fiber satisfies a universal stress-strain relationship driven by a Young's modulus, a contraction coefficient scaling the fictitious thermal strain, a maximum contraction stress and a softening parameter describing the sliding effects between actin and myosin filaments. To account for the inherent variability of cellular responses, large populations of SMCs are modeled with the finite-element method, each cell having a random number and a random arrangement of stress fibers. Moreover, the level of myosin activation in each stress fiber satisfies a Weibull probability density function. Model predictions are compared to traction force measurements on different SMC lineages. It is demonstrated that the model not only predicts well the effects of substrate stiffness on cellular traction, but it can also successfully approximate the statistical variations of cellular tractions induced by intercellular variability. Finally, stresses in the nuclear envelope and in the nucleus are computed with the model, showing that the variations of cytoskeletal forces induced by substrate stiffness directly induce deformations of the nucleus which can potentially alter gene expression. The predictability of the model combined to its relative simplicity are promising assets for further investigation of stiffness sensing in 3D environments. Eventually, this could contribute to decipher the effects of mechanosensitivity impairment, which are known to be at the root of aortic aneurysms.

MasR and pGCA receptor activation protects primary vascular smooth muscle cells and endothelial cells against oxidative stress via inhibition of intracellular calcium.

Cardiovascular diseases (CVDs)are associated with vascular smooth muscle cell (VSMC)and endothelial cell (EC)damage. Angiotensin1-7 (Ang1-7) and B-type natriuretic peptide (BNP)are responsible for vasodilation and regulation of blood flow. These protective effects of BNP are primarily mediated by the activation of sGCs/cGMP/cGKIpathway. Conversely, Ang1-7 inhibits Angiotensin II-induced contraction and oxidative stress via Mas receptor activation. Thus, the aim of the study was to determine the effect of co-activation of MasR and particulate guanylate cyclase receptor (pGCA)pathways by synthesized novel peptide (NP)in oxidative stress-induced VSMCs and ECs. MTTand Griess reagent assay kits were used for the standardization of the oxidative stress (H2 O2 ) induced model in VSMCs. The expression of targeted receptors in VSMC was done by RT-PCRand Western blot analysis. Protective effect of NP in VSMC and EC was determined by immunocytochemistry, FACS analysis, and Western blot analysis. Underlying mechanisms of EC-dependent VSMC relaxation were done by determining downstream mRNA gene expression and intracellular calcium imaging of cells. Synthesized NP significantly improved oxidative stress-induced injury in VSMCs. Remarkably, the actions of NP were superior to that of the Ang1-7 and BNP alone. Further, a mechanistic study in VSMC and EC suggested the involvement of upstream mediators of calcium inhibition for the therapeutic effect.NP is reported to possess vascular protective activities and is also involved in the improvement of endothelial damage. Moreover, it is highly effective than that of individual peptides BNP and Ang1-7 and therefore it may represent a promising strategy for CVDs.

Comparing Non-Stress Test versus Umbilical Artery Doppler Velocimetry among Aample of High-risk Pregnant Women in Erbil City

Background: The mainstay of care for lowering maternal and perinatal mortality and morbidity is antepartum foetal surveillance. Numerous techniques are used, including fetal movements, Vibroacoustic stimulation tests, contraction stress tests, biophysical profiles of the fetus, modified biophysical profiles, non-stress testing and Doppler Umbilical artery of the fetus's. The fetal heart reaction to internal and extrinsic stimuli is seen on electronic fetal monitoring devices. The benefit of high resolution dynamic ultrasonography and Doppler imaging is that it allows for the visualization of the fetus and its surroundings as well as the monitoring of fetal health by measuring utero-placental circulation. Patients and techniques: The cross-sectional investigation including 120 pregnant women who visited the Maternity Teaching Hospital between 26 June and 31 August 2022 and complained of decreased uterine contractions have been included. The questionnaire included sociodemographic data, obstetrical data, information on the fetal outcome and method of delivery. In accordance with the American Academy of Obstetricians and Gynecologists, cardiotopography was utilized to conduct a non-stress test, and the outcomes were categorized as reactive and non-reactive. Cardiotopography was used to perform a non-stress test, and the results were classified as reactive or non-reactive in accordance with the American Academy of Obstetricians and Gynecologists. Also, during 32 weeks or more of gestation, the inferior vena cava was not compressed by the gravid uterus during ultrasonography of the umbilical arteries, which was performed in a semi-recumbent position with a slight lateral tilt. Result: Based on NST and Doppler velocimetry of the umbilical artery, all cases were classified into two groups. The outcomes of the two tests didn't significantly differ from one another. The rate of Cesarean section (CS) was 46.1% among women with non-reactive (abnormal) CTG, compared with 25% among women with normal CTG (p = 0.0316). Only one neonate (1.3%) died among women with normal CTG, while none of the neonates died among women with abnormal CTG. The rate of CS among women with abnormal ultrasonography was 80% compared to women (11%) with normal ultrasonography. Furthermore, one neonate (2.1%) in the group of abnormal doppler, compared with 0% in the normal group. Conclusion: NST and umbilical artery Doppler of are sensitive and specific tests with strong positive prognostic value to suggest a poor prognosis for the newborn. Doppler velocimetry of umbilical artery is more important than a non-stress test because it lowers the likelihood of a CS birth in non-reactive non-stress test situations without increasing the risk of perinatal morbidity and mortality. Bangladesh Journal of Medical Science Vol.22 (Special Issue) 2023 p.10-17