Impacts of entropy generation in radiative peristaltic flow of variable viscosity nanomaterial.

Current analysis highlights the aspects of different nanoparticles in peristalsis with entropy generation. Mathematical equations of considered problem are modelled via conservation laws for mass, momentum and energy. Such equations contain variable viscosity, nonlinear thermal radiation, viscous dissipation, heat generation/absorption and mixed convection aspects. Boundary conditions comprise the second order velocity and first order thermal slip effects. Entropy expression is obtained by utilization thermodynamics. Simplified and dimensionless forms of the considered conservative laws are obtained through lubrication technique. Resulting system of equations subject to the considered boundary conditions is solved numerically via built-in shooting procedure in Mathematica. Such numerical procedure is very suitable to obtain numerical results directly and fastly in the form of graphs. Further all the considered flow quantities are discussed graphically for the significant parameters of interest in detail. Both velocity and temperature are decreasing against large volume fraction parameter. Increasing temperature dependent viscosity effects decrease the entropy and enhance the Bejan number.

Peristaltic transport of Rabinowitsch nanofluid with moving microorganisms.

The key objective of the current examination is to examine a symmetrically peristaltic movement of microorganisms in a Rabinowitsch fluid (RF). The Boussinesq approximation, buoyancy-driven flow, where the density with gravity force term is taken as a linear function of heat and concentrations, is kept in mind. The flow moves with thermophoretic particle deposition in a horizontal tube with peristalsis. The heat distribution and volume concentration are revealed by temperature radiation and chemical reaction characteristics. The originality of the existing study arises from the importance of realizing the benefits or the threats that nanoparticles, microbes, and bacteria cause in the flow inside peristaltic tubes. The results are an attempt to understand what factors perform additional advantages and or reduce damages. The controlling nonlinear partial differential equations (PDEs) are made simpler by employing the long wavelength (LWL) and low-Reynolds numeral (LRN) approximations. These equations are subjected to a set of non-dimensional transformations that result in a collection of nonlinear ordinary differential equations (ODEs). By employing the Homotopy perturbation method (HPM), the configuration of equational analytical solutions is examined. Analytical and graphical descriptions are provided for the distributions of axial speed, heat, microbes, and nanoparticles under the influence of these physical characteristics. The important findings of the current work may help to comprehend the properties of several variations in numerous biological situations. It is found that the microorganisms condensation decays with the rise of all the operational parameters. This means that the development of all these factors benefits in shrinking the existence of harmful microbes, viruses, and bacteria in the human body's peristaltic tubes, especially in the digestive system, and large and small intestines.

Effect of valve spacing on peristaltic pumping.

Peristaltic fluid pumping due to a periodically propagating contraction wave in a vessel fitted with one-way elastic valves is investigated numerically. It is concluded that the valve spacing within the vessel relative to the contraction wavelength plays a critical role in providing efficient pumping. When the valve spacing does not match the wavelength, the valves open asynchronously and the volume of the vessel segments bounded by two consecutive valves changes periodically, thereby inducing volumetric fluid pumping. The volumetric pumping leads to higher pumping flowrate and efficiency against an adverse pressure gradient. The optimum pumping occurs when the ratio of valve spacing to contraction wavelength is about2/3. This pumping regime is characterized by a longer period during which the valves are open. The results are useful for further understanding the pumping features of lymphatic system and provide insight into the design of biomimetic pumping devices.

Impact of activation energy and variable properties on peristaltic flow through porous wall channel.

The current study discusses the peristaltic flow of Jeffrey fluid through a porous wall channel. Magnetohydrodynamic (MHD) effects are also considered while formulating the problem. Heat and mass transfers are discussed in the presence of activation energy and constant heat source/sink effects. A chemical reaction is also part of the analysis. The Lubrication approach is adopted for the simplification of resulting non-linear equations. MATHEMATICA command, NDSolve, is used to discuss the results graphically for various flow parameters like Hartman number [Formula: see text], porosity parameter [Formula: see text], slip parameters ([Formula: see text]), Schmidt [Formula: see text], Soret [Formula: see text] and Prandtl [Formula: see text] numbers, and many others. Parabolic behavior for velocity and sinusoidal nature for heat transfer and pressure gradient is noticed. Results indicate that the velocity is greatly affected by varying values of slip parameters (γ's) and Hartman number [Formula: see text]. Enhancing the viscoelastic nature of fluid causes an increase in velocity. Similar behavior is noticed for velocity and temperature profiles. The decreasing trend is shown by concentration when the value of the chemical reaction and temperature ratio parameters is enhanced. Thus, the study presented in the current analysis can be used to study many human physiological systems especially, the blood flow. Since Jeffrey's fluid exhibits the same characteristics as observed for blood.

An earthworm-like modular soft robot for locomotion in multi-terrain environments.

Robotic locomotion in subterranean environments is still unsolved, and it requires innovative designs and strategies to overcome the challenges of burrowing and moving in unstructured conditions with high pressure and friction at depths of a few centimeters. Inspired by antagonistic muscle contractions and constant volume coelomic chambers observed in earthworms, we designed and developed a modular soft robot based on a peristaltic soft actuator (PSA). The PSA demonstrates two active configurations from a neutral state by switching the input source between positive and negative pressure. PSA generates a longitudinal force for axial penetration and a radial force for anchorage, through bidirectional deformation of the central bellows-like structure, which demonstrates its versatility and ease of control. The performance of PSA depends on the amount and type of fluid confined in an elastomer chamber, generating different forces and displacements. The assembled robot with five PSA modules enabled to perform peristaltic locomotion in different media. The role of friction was also investigated during experimental locomotion tests by attaching passive scales like earthworm setae to the ventral side of the robot. This study proposes a new method for developing a peristaltic earthworm-like soft robot and provides a better understanding of locomotion in different environments.

Underlying etiology associated with the diagnosis of absent contractility on high resolution esophageal manometry / Etiologías subyacentes asociadas al diagnóstico de contractilidad ausente en la manometría esofágica de alta resolución

Background/Aims: Absent contractility is considered a disorder of peristalsis. The literature about the etiology and clinical characteristics is scarce and the evidence on systemic diseases associated with this esophageal disorder is limited. Therefore, we aimed to determine the etiology of absent contractility in our population using the clinical algorithm recently described in the literature. Methods: We conducted a retrospective, descriptive study at a single tertiary hospital of all patients diagnosed of absent contractility between May 2018 and February 2020. Data on demographic characteristics, medication, comorbidities, and laboratory and paraclinical tests were recorded from clinical records. Results: A total of 72 patients with absent contractility were included for analysis. There was a predominance of female sex (n=43, 59.7%), with a mean age of 55.4 (±15.0) years. We identified a systemic disorder associated with absent contractility in 64 (88.9%) patients. From these, 31 (43.1%) patients were diagnosed with a systemic autoimmune disease, 26 (36.1%) patients were considered to have absent contractility secondary to pathological exposure to acid-reflux and 15 (20.8%) patients were diagnosed with other non-autoimmune systemic disorders. In the remaining eight (11.1%) patients, there were no underlying systemic disorders that could justify the diagnosis of absent contractility. Conclusions: A systematic approach to search for an underlying cause in patients diagnosed with absent contractility is warranted. Up to 90% of patients with absent contractility have a systemic disorder associated with this condition.(AU)

Antecedentes: La contractilidad ausente se considera un trastorno de la peristalsis esofágica. La literatura que existe sobre la etiología y las características clínicas es escasa y la evidencia sobre enfermedades sistémicas asociadas a este trastorno esofágico es limitada. Nuestro objetivo fue determinar la etiología de la contractilidad ausente en nuestra población utilizando el algoritmo clínico recientemente descrito en la literatura. Métodos: Se realizó un estudio descriptivo retrospectivo en un hospital terciario de todos los pacientes diagnosticados de ausencia de contractilidad entre mayo de 2018 y febrero de 2020. Se recogieron datos de características demográficas, medicación, comorbilidades y pruebas de laboratorio y estudios paraclínicos. Resultados: Se incluyeron para el análisis un total de 72 pacientes con ausencia de contractilidad. Predominó el sexo femenino (n=43, 59,7%), con una edad media de 55,4 (±15,0) años. Identificamos un trastorno sistémico asociado con la ausencia de contractilidad en 64 (88,9%) pacientes. De estos 31 (43,1%) pacientes fueron diagnosticados de una enfermedad autoinmune sistémica, 26 (36,1%) pacientes se consideraron con ausencia de contractilidad secundaria a exposición patológica al reflujo ácido y 15 (20,8%) fueron diagnosticados con otras enfermedades no autoinmunes sistémicas. En los 8 pacientes restantes (11,1%) no hubo trastornos sistémicos subyacentes que pudieran justificar el diagnóstico de contractilidad ausente. Conclusiones: Un enfoque sistemático está justificado para investigar una causa subyacente en pacientes diagnosticados de contractilidad ausente. Hasta el 90% de los pacientes con contractilidad ausente tienen un trastorno sistémico asociado con esta afectación de la motilidad esofágica.(AU)

Role of segmental contraction in the small intestinal digestion: A computational approach to study the physics behind the luminal mixing and transport.

Segmentation is well known to digest the food rich in proteins, starch, and lipids; however, the mechanism leading to the digestion remains unclear. In this study, a theoretical model for segmental contractions of the small intestine is developed using lubrication method to explore the mechanisms involved. Here, the nonlinear partial differential equations governing the fluid flow were normalized in viscous regime and solved semi-analytically for a power law fluid under long wavelength approximation on a MatlabTM platform. Study indicates that shearing is highest at the 1st and 4th mid-occlusion in comparison to 2nd and 3rd mid-occlusion. Parametric study indicates that the flow is sensitive to - the span of segmentation or wavelength of the wave, occlusion of the wave and frequency of the contraction; with shearing being highest for dilatants. Shearing is more prominent at higher occlusion (>50 %) and frequency (>6Hz). Further, mixing is more prominent at the steep regions of the wave; having intensity of mixing highest for the outer waves in comparison to waves at mid-region of the segmentation. The power demand is found to be greater in segmentation and has the following precedence - frequency, wavelength, flow behavior index, and occlusion (up to 80 %). Further, multiplicity of the wave gives rise to multiple zones of mixing which increases the rate of mixing of the contents. Suggesting that, the segmentation primarily serves the purpose of mixing. The study will be useful to explore novel therapeutic strategies of managing patients suffering from various motility-associated disorders of the small intestine.

Effects of peristaltic amplitude and frequency on gastric emptying and mixing: a simulation study.

The amplitude and frequency of peristaltic contractions are two major parameters for assessing gastric motility. However, it is not fully understood how these parameters affect the important functions of the stomach, such as gastric mixing and emptying. This study aimed to quantify the effects of peristaltic amplitude and frequency on gastric mixing and emptying using computational fluid dynamics simulation of gastric flow with an anatomically realistic model of the stomach. Our results suggest that both the increase and decrease in peristaltic amplitude have a significant impact on mixing strength and emptying rate. For example, when the peristaltic amplitude was 1.2 times higher than normal, the emptying rate was 2.7 times faster, whereas when the amplitude was half, the emptying rate was 4.2 times slower. Moreover, the emptying rate increased more than proportionally with the peristaltic frequency. The nearest contraction wave to the pylorus and the subsequent waves promoted gastric emptying. These results suggest the importance of maintaining parameters within normal ranges to achieve healthy gastric function.

Recording and analysis of slow waves of the small intestine of mice with heart failure.

BACKGROUND: Gastrointestinal (GI) symptoms in heart failure (HF) patients are associated with increased morbidity and mortality. We hypothesized that HF reduces bioelectrical activity underlying peristalsis. In this study, we aimed to establish a method to capture and analyze slow waves (SW) in the small intestine in mice with HF. METHODS: We established a model of HF secondary to coronary artery disease in mice overexpressing tissue-nonspecific alkaline phosphatase (TNAP) in endothelial cells. The myoelectric activity was recorded from the small intestine in live animals under anesthesia. The low- and high-frequency components of SW were isolated in MATLAB and compared between the control (n = 12) and eTNAP groups (n = 8). C-kit-positive interstitial cells of Cajal (ICC) and Pgp9.5-positive myenteric neurons were detected by immunofluorescence. Myenteric ganglia were assessed by hematoxylin and eosin (H&E) staining. RESULTS: SW activity was successfully captured in vivo, with both high- and low-frequency components. Low-frequency component of SW was not different between endothelial TNAP (eTNAP) and control mice (mean[95% CI]: 0.032[0.025-0.039] vs. 0.040[0.028-0.052]). High-frequency component of SW showed a reduction eTNAP mice relative to controls (0.221[0.140-0.302] vs. 0.394[0.295-0.489], p < 0.01). Dysrhythmia was also apparent upon visual review of signals. The density of ICC and neuronal networks remained the same between the two groups. No significant reduction in the size of myenteric ganglia of eTNAP mice was observed. CONCLUSIONS: A method to acquire SW activity from small intestines in vivo and isolate low- and high-frequency components was established. The results indicate that HF might be associated with reduced high-frequency SW activity.

Post-reflux swallow-induced peristaltic wave is impaired in laryngopharyngeal and gastro-oesophageal reflux disease.

INTRODUCTION: Laryngopharyngeal reflux (LPR) and gastro-oesophageal reflux disease (GORD) result from the reflux of gastric contents. The post-reflux swallow-induced peristaltic wave (PSPW) is an oesophageal reflex that facilitates chemical clearance of gastric contents following reflux events. PSPW index is a novel parameter that has been validated in assessing the effectiveness of chemical clearance in GORD, but not in LPR. This study aimed to assess chemical clearance in LPR and GORD by measuring PSPW indices in a consecutive series of patients. METHODS: Reviewers blindly analysed off-therapy impedance-pH tracings from 187 patients clinically categorized as LPR (n = 105) or GORD (n = 82) by predominant symptom profile. Conventional impedance-pH measures and PSPW indices were analysed. RESULTS: Mean PSPW index in the LPR group was higher than in the GORD group (39.7% (±17.7%) vs. 20.6% (±13.4%); p < 0.001). Abnormally low PSPW index (<61%) was seen in 85 (81%) of the LPR group, and 80 (97.6%) of the GORD group (p < 0.001). Area under the ROC curve for PSPW index to diagnose LPR was 0.83 (95% CI: 0.767-0.889; p < 0.001). CONCLUSION: Post-reflux swallow-induced peristaltic wave was impaired in patients with LPR as well as oesophageal GORD, indicating an abnormality of chemical clearance following a reflux episode in both groups. PSPW index was more severely impaired in gastro-oesophageal reflux disease (GORD). The present study shows PSPW index is useful in the diagnosis of both LPR and GORD and exposes an abnormality of clearance of the oesophagus.

Mechanosensitive Enteric Neurons (MEN) at Work.

In the last decade, we characterized an enteric neuronal subpopulation of multifunctional mechanosensitive enteric neurons (MEN) while studying the gastrointestinal peristalsis. MEN have been described in a variety of gastrointestinal regions and species. This chapter summarizes existing data on MEN, describing their proportions, firing behaviors, adaptation musters, and chemical phenotypes. We also discuss MEN sensitivity to different mechanical stimulus qualities such as compression and tension along with pharmacology of their responses.

Influence of variable velocity slip condition and activation energy on MHD peristaltic flow of Prandtl nanofluid through a non-uniform channel.

This study is carried out to analyze the problem of mixed convection magnet nanoflow of Prandtl fluid through a non-uniform channel with peristalsis. The external influences of activation energy and non-constant velocity slip are given full consideration. The mentioned fluid is expressed as a governing equations system, and then these equations are converted with non-dimensional parameter values to a system of ordinary differential equations. The converted system of equations is solved in terms of y and then graphs and sketches are offered using the generalized differential transform method. Graphs and results for volume friction as well as velocity profile, concentration, and temperature distributions are obtained. Results show development in the velocity profile of fluid distribution through high values of the non-constant velocity slip effect. The present study is alleged to deliver more opportunities to advance the applications of the drug-carrying system in hypoxic tumor areas with aid of identifying the flow mechanisms.

Thermal transport of biological base fluid with copper and iron oxide nanoparticles in wavy channel.

The nanoparticles are frequently used in biomedical science for the treatment of diseases like cancer and these nanoparticles are injected in blood which is transported in the cardiovascular system on the principle of peristalsis. This study elaborates the effects of Lorentz force and joule heating on the peristaltic flow of copper and iron oxide suspended blood based nanofluid in a complex wavy non-uniform curved channel. The Brinkman model is utilized for the temperature dependent viscosity and thermal conductivity. The problem is formulated using the fundamental laws in terms of coupled partial differential equations which are simplified using the creeping flow phenomenon. The graphical results for velocity, temperature, streamlines, and axial pressure are simulated numerically. The concluded observations deduce that the solid volume fraction of nanoparticles reduces the velocity and enhance the pressure gradient and accumulation of trapping bolus in the upper half of the curved channel is noticed for temperature dependent viscosity.

4D live imaging and computational modeling of a functional gut-on-a-chip evaluate how peristalsis facilitates enteric pathogen invasion.

Physical forces are essential to biological function, but their impact at the tissue level is not fully understood. The gut is under continuous mechanical stress because of peristalsis. To assess the influence of mechanical cues on enteropathogen invasion, we combine computational imaging with a mechanically active gut-on-a-chip. After infecting the device with either of two microbes, we image their behavior in real time while mapping the mechanical stress within the tissue. This is achieved by reconstructing three-dimensional videos of the ongoing invasion and leveraging on-manifold inverse problems together with viscoelastic rheology. Our results show that peristalsis accelerates the destruction and invasion of intestinal tissue by Entamoeba histolytica and colonization by Shigella flexneri. Local tension facilitates parasite penetration and activates virulence genes in the bacteria. Overall, our work highlights the fundamental role of physical cues during host-pathogen interactions and introduces a framework that opens the door to study mechanobiology on deformable tissues.

Esophageal wall compliance/stiffness during peristalsis in patients with functional dysphagia and high-amplitude esophageal contractions.

Recent studies that utilized distension/contraction plots to study peristalsis reveal poor distension of the esophagus in patients with functional dysphagia and high-amplitude contractions [high-amplitude esophageal contractions (HAECs)] even though the contraction phase of peristalsis is normal in these patients. Our goal was to determine biomechanical properties of the esophageal wall and bolus flow characteristics in patients with functional dysphagia and HAEC during primary peristalsis. Studies were performed on 30 healthy subjects, 30 patients with functional dysphagia, and 25 patients with HAEC. Subjects swallowed 10 mL, 0.5 N saline bolus in the Trendelenburg position to study primary peristalsis. A custom-built software (Dplots) determined peak distension from the impedance measurements, pressure at peak distension, wall tension (pressure × radius), wall distensibility [cross-sectional area (CSA)/pressure], and bolus flow (cm3/s) in four segments of esophagus (between upper and lower esophageal sphincter). Luminal CSA of distal esophagus was smaller, and average bolus flow rate was faster in patients with functional dysphagia and HAEC. Esophageal wall distensibility, a measure of esophageal wall compliance was lower and wall tension was higher in the distal esophagus of both patient groups compared with normal subjects. Ultrasound imaging confirmed poor distension of the esophagus. A trend toward greater wall thickness at the peak of distension was found in patients with functional dysphagia compared with normal subjects. A stiffer or noncompliant esophageal wall is the reason for poor distension of the esophagus during primary peristalsis in patients with functional dysphagia and HAEC.NEW & NOTEWORTHY We studied healthy asymptomatic subject, patients with functional dysphagia (FD), and patients with high-amplitude esophageal contractions (HAEC). Our data show that in patients with HAEC and functional dysphagia, luminal distension is smaller (low luminal CSA at peak distension), intraluminal pressure is higher, and liquid bolus travels faster through the esophagus as compared with normal subjects. We conclude that patients with functional dysphagia and HAEC have a stiffer distal esophageal wall during bolus transport related to primary peristalsis.

A bioinspired apparatus for modeling peristaltic pumping in biophysical flows.

In this study, we present a novel, bioinspired experimental apparatus, its construction, data acquisition methodology, and validation for the study of peristaltic flows. The apparatus consists of a series of stepper motor actuators, which deflect a deformable membrane to produce peristaltic flows. We show that this apparatus design has significant advantages over previous designs that have been used to study peristaltic flows by offering a much wider range of modeling capabilities. Comparisons between the capabilities of our apparatus and previous ones show our apparatus spanning a larger range of wavelengthλ, wave speedc, amplitudeA, and waveform (i.e. the apparatus is not constrained to nondispersive waves or to a sinusoidal shape). This large parameter range makes the apparatus a useful tool for biomimetic experimental modeling, particularly for systems that have complex waveforms, such as peristaltic flows in perivascular vessels, arteries, the cochlea, and the urethra. We provide details on the experimental design and construction for ease of reconstruction to the reader. The apparatus capabilities are validated for a large parameter range by comparing experimental measurements to analytic results from (Ibanezet al2021Phys. Rev. Fluids6103101) for high Reynolds number (Re > 1) and (Jaffrin and Shapiro 1971Annu. Rev. Fluid Mech.33-37) for low Reynolds number (Re < 1) applications. We show that the apparatus is useful for biophysical peristaltic studies and has potential applications in other types of studies.

Modification of Tubings for Peristaltic Pumping of Biopharmaceutics.

Protein particle formation during peristaltic pumping of biopharmaceuticals is due to protein film formation on the inner tubing surface followed by rupture of the film by the roller movement. Protein adsorption can be prevented by addition of surfactants as well as by increasing the hydrophilicity of the inner surface. Attempts based on covalent surface coating were mechanically not stable against the stress of roller movement. We successfully incorporated surface segregating smart polymers based on a polydimethylsiloxane (PDMS) backbone and polyethylene glycol (PEG) side blocks in the tubing wall matrix. For this we applied an easy, reproducible and cost-effective process based on soaking of tubing in toluene containing the PDMS-PEG copolymer. With this tubing modification we could drastically reduce protein particle formation during peristaltic pumping of a monoclonal antibody and human growth hormone (HGH) formulation in silicone and thermoplastic elastomer-based tubing. The modification did not impact the tubing integrity during pumping while hydrophilicity was increased and protein adsorption was prevented. Free PDMS-PEG copolymer might have an additional stabilizing effect, but less than 50 ppm of the PDMS-PEG copolymer leached from the modified tubing during 1 h of pumping in the experimental setup. In summary, we present a new method for the modification of tubings which reduces protein adsorption and particle formation during any operation involving peristaltic pumping, e.g. transfer, filling, or tangential flow filtration.

Thermal micropolar and couple stresses effects on peristaltic flow of biviscosity nanofluid through a porous medium.

The main aim of the current study is to analyze couple stresses effects on MHD peristaltic transport of a micropolar non-Newtonian nanofluid. The fluid flows through a porous media between two horizontal co-axial tubes. The effects of radiation, chemical reaction, viscous and ohmic dissipation are considered. The inner tube is solid and uniform, while the outer tube has a sinusoidal wave traveling down its wall. The governing equations have been simplified using low-Reynolds number and long wave-length approximations, thus a semi-analytical solutions have been obtained using the homotopy perturbation method. Numerical results for the behaviors of the axial velocity, microrotation velocity, temperature and nanoparticles concentration with the physical parameters are depicted graphically through a set of graphs. Furthermore, the values of the skin friction coefficient, Nusselt and nano Sherwood numbers are computed and presented graphically through some draws. Moreover, the trapping phenomenon is discussed throughout a set of figures. The present study is very important in many medical applications, as the gastric juice motion in the small intestine when an endoscope is inserted through it. Further, gold nanoparticles are utilized in the remedy of cancer tumor.

An endometrial receptivity scoring system basing on the endometrial thickness, volume, echo, peristalsis, and blood flow evaluated by ultrasonography.

Background: Establishing a successful pregnancy depends on the endometrium and the embryo. It is estimated that suboptimal endometrial receptivity account for one-third of implantation failures. Despite the indepth understanding of the processes associated with embryo-endometrial cross-talk, little progress has been achieved for diagnosis and treatments for suboptimal endometrial receptivity. Methods: This retrospective study included women undergoing their first frozen-thawed embryo transfer (FET) cycles at our reproductive medicine center from March 2021 to August 2021. Transvaginal three-dimensional (3D) ultrasound was performed in the morning on the day of embryo transfer for all the thawed embryo transfer patients, to evaluate endometrial receptivity, including endometrial thickness, echogenicity, volume, movement and blood flow. Results: A total number of 562 patients of FET with 315 pregnancies (56.0%) was analyzed. It was found that only the echo of the endometrial central line was different between the pregnant group and non-pregnant group. Other parameters, such as endometrial thickness, volume, endometrial peristalsis, or the endometrial blood flow were not statistically different between the two groups. Then, according to the relationship between the different groups and the clinical pregnancy rate, a score of 0 to 2 was respectively scored. The sum of the scores for the six items was the patient's endometrial receptivity score. It showed that the clinical pregnancy rate increased as the endometrial receptivity score increased, and when the receptivity score reaches at least 5, the clinical pregnancy rate is significantly improved (63.7% versus 49.5%, P=0.001). Conclusion: We developed an endometrial receptivity scoring system and demonstrated its validity. It may aid clinicians in choosing the useful marker in clinical practice and for informing further research.

[Application of acupuncture in inhibiting intestinal peristalsis in colonoscopy].

Acupuncture regulating gastrointestinal motility has the characteristics of bidirectional benign regulation, acupoint specificity and immediacy. And its regulation is mainly achieved through the "neuro-endocrine-immune" network system. Acupuncture at Neiguan (PC 6) and Hegu (LI 4) to inhibit intestinal peristalsis may have good application value in colonoscopy.