Search

In Newtonian mechanics, time and space are perceived as absolute entities. In Einstein’s relativity theory, time is frame dependent. Time is also affected by gravitational field and as the field varies in space, time also varies throughout space. In the present article, the thermodynamic-based time is investigated. In macroscopic view of thermodynamics, energy is conserved in every system or process. On the other hand, exergy (availability) is not conserved and can be destroyed, and “irreversibility” is generated. Since each thermodynamic system may generate different amounts of irreversibility, this quantity is system dependent. The present article investigates the characteristics of entity irreversibility. (1) It is found that the entity behaves in the similar manner as the clock time in the standard configuration of inertial frames under Lorentz transformation. (2) It is also found that the entity is affected by gravity fields in the similar manner as the clock time. We have demonstrated that, like clock time, irreversibility is frame dependent, and affected by gravity in the similar manner as the clock time. For these reasons, we propose to call the irreversibility of the system as the thermodynamic time. The time’s arrow is automatically satisfied, since irreversibility generation always proceeds in one direction (toward future). Based on the strength of the findings (1) and (2), a possible application of the irreversibility is an interpretation and management of the aging of biological systems. It is shown by other authors that entropy generation (equivalent to irreversibility) is a parameter for the human life span. Our sensation of time flow may be attributed to the flow of availability and destruction of it through the living system.

In special relativity, the time dilation formula has been obtained by particles propagation in a straight line trajectory relative to an observer in motion. Up to now, there are no available formulas for other possible trajectories of particles. However, this paper obtains formulas of time dilation for several trajectories of particle such as parabolic, elliptic, and circular and finds a relatively accurate trajectory. The obtained formulas are employed in order to analyze the time dilation of the muon particles decay. In this paper, it is found that the time dilation of the parabolic and the elliptical trajectories exceed the corresponding results utilizing the standard Lorentz-Einstein time dilation formula. Consequently, if we are able to control the trajectory of unstable particles by some external forces, then their life-times might be increased. Probably, the increase in lifetime via a curved trajectory occurs at lower relative velocity & acceleration energy if compared to the straight line trajectory. In addition, the circular trajectory leads to multiple values of time dilation at certain velocities of an observer in motion, which may give an interpretation of fluctuations of time dilation in quantum mechanics. The result arises from the present relatively accurate formula of time dilation that is very close to the experimental data of muon decay (CERN experiment) when it is compared to the result obtained by the Lorentz-Einstein formula. Finally, it may be concluded that the time dilation not only depends on relative velocity and acceleration energy of particles but also on curved trajectories. The present work may attract other researchers to study different trajectories.

For the first time, the possibility of measuring the difference in gravitational potentials and orthometric heights by a quantum level based on the gravitational effect of time dilation using ground communication lines is considered. The duplex mode of measurements using two opposite radio channels is theoretically described. The dilation effect was experimentally measured using a one-way radio communication line implemented based on a fiber-optic link. For measurements, stationary and mobile (transportable) quantum hydrogen clocks were used with relative instabilities of (0.5-0.7)×10-15 and 1×10-15, respectively. It was found that in the experiment, the gravitational redshift of the frequency between the utilized clocks has two components: the redshift of the master oscillator frequency and the classical redshift in the radio channel. Based on the measurement results, the displacement height of the transportable quantum hydrogen clock was calculated to be (–34.0 ± 0.8) m, while the actual height was –34 m. [ABSTRACT FROM AUTHOR]

Case: A 43-year-old woman presented with pain, paresthesia, and coldness of the right upper extremity suggestive of the diagnosis of thoracic outlet syndrome. Three-dimensional computed tomography angiography revealed that the right subclavian artery was constricted because it traveled over an abnormal first rib. After anticoagulation and antithrombotic therapy, the patient underwent resection of the abnormal first rib. Postoperative angiography documented improvement over time of the poststenotic dilatation and recanalization of the subclavian artery capable of delivering almost normal distal flow. Conclusion: Arterial reconstruction is not always necessary for the treatment of arterial thoracic outlet syndrome associated with poststenotic dilatation of the subclavian artery. [ABSTRACT FROM AUTHOR]

In this article, we want to analyze a relativistic paradox in a very simple way, which, in our opinion, could be useful for a pedagogical purpose. Indeed we want to solve it using only Einstein's relativity principle and the Einstein equivalence principle. We think it could be useful from a pedagogical point of view. [ABSTRACT FROM AUTHOR]

We show that masses of binary black hole mergers are overestimated, since a large gravitational redshift is not taken into account. Such a phenomenon occurs due to time dilation in a close neighborhood of any black hole. This fact allows us to explain a high mass gap between observed binary neutron stars and calculated binary black hole mergers. We also present other reasons why masses of black hole mergers are determined incorrectly. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate mifepristone impact on osmotic dilator placement and procedural outcomes when given 18 to 24 hours before dilator placement for dilation and evacuation (D&E) at 18 weeks 0 days to 23 weeks 6 days gestation.Study Design: We performed a randomized, double-blind, placebo-controlled trial from April 2019 through February 2021, enrolling participants undergoing osmotic dilator (Dilapan) placement for a planned, next-day D&E. Participants took mifepristone 200 mg or placebo orally 18 to 24 hours before dilator placement. We used a gestational age-based protocol for minimum number of dilators. Our primary outcome was the proportion of participants for whom 2 or more additional dilators could be placed compared to the minimum gestational age-based standard. We secondarily evaluated cervical dilation after dilator removal in the operating room, subjective procedure ease, and complication rates (cervical laceration, uterine perforation, blood transfusion, infection, hospitalization, or extramural delivery).Results: Of the planned 66 participants, we enrolled 44 (stopped due to coronavirus disease 2019-related obstacles), and 41 (19 mifepristone; 22 placebo) completed the study. We placed 2 or more additional dilators compared to standard in 7 (36.8%) and 3 (13.6%) participants after mifepristone and placebo, respectively (p = 0.14). We measured greater median initial cervical dilation in the mifepristone (3.2 cm[2.6-3.6]) compared to placebo (2.6 cm[2.2-3.0]) group, p = 0.03. Surgeon's perception of procedure being "easy" (8/19[42.1] vs 9/22[40.9], respectively, p = 1.00) and complication rate (3/19[15.8%] vs 3/22[13.6], respectively, p = 1.00) did not differ.Conclusion: Our underpowered study did not demonstrate a difference in cervical dilator placement, but mifepristone 18 to 24 hours prior to dilators increases cervical dilation without increasing complications.Implications: Mifepristone 18 to 24 hours prior to cervical dilator placement may be a useful adjunct to cervical dilators based on increased cervical dilation at time of procedure; however, logistical barriers, such as an additional visit, may preclude routine adoption without definite clinical benefit. [ABSTRACT FROM AUTHOR]

The paper develops the implicit as well as explicit meaning which evokes Stanisław Lem's concept of the Body and the Corporality portrayed in the novel Return from the Stars. Moreover, Lem's novel about an astronaut Hal Bregg and his return on Earth is analysed. In this novel author uses the idea of Einstein's twin paradox. Hal Bergg--the stereotype of masculinity--is confronted with decadent and egalitarian society, which may be refers to the reunion masculinity with femininity. Such storyline shows the multidimensionality of the issue of Corporality, and presents the Body as a epistemological metaphor of modernism and postmodernism. In addition, the Body is depicted in the Return of the Stars as a figure of a mask and a costume. Furthermore, the Body in Lem's novel is also interpreted as part of the Universe--as the boundary between what is temporary and what is infinite and transcendent. [ABSTRACT FROM AUTHOR]

The so called modern physics is at present included in the curricula of high school. Therefore, we often organize in-depth lessons on quantum mechanics and on the special theory of relativity (SR). In the following sections, we want to show a lesson given by the first author of this paper. He proposes to students a proportion to deduce relativistic time dilation and length contraction without knowing the Lorentz transformations. [ABSTRACT FROM AUTHOR]

Background: Benign esophageal strictures are a frequent complication after esophageal surgery or extensive endoscopic submucosal dissection. Endoscopic dilation is the preferred treatment in clinical practice. However, the allocation of time for each dilation is unclear. The aim of this study was to evaluate the appropriate duration of endoscopic dilation for benign esophageal strictures after esophageal surgery or endoscopic submucosal dissection. Methods: Patients with benign esophageal strictures after esophageal surgery or endoscopic submucosal dissection between July 2010 and July 2018 were retrospectively included in this study. According to the dilation time (1, 3, 5 min), patients were divided into three groups. The clinical effects and adverse events were compared among the three groups. Results: Altogether, 57 patients, including 21 in the 1-min group, 18 in the 3-min group and 18 in the 5-min group, were included. All patients underwent endoscopic treatment successfully. The stricture recurrence rate was 76.19% in the 1-min group, 55.56% in the 3-min group and 61.11% in the 5-min group. The median overall dysphagia-free period was 2.60 (range, 0.80–12.00) months in the 1-min group, 6.60 (range, 1.80–12.00) months in the 3-min group and 6.25 (range, 2.40–12.00) months in the 5-min group (P < 0.05). For patients who developed stricture recurrence, the mean dysphagia-free periods were 2.26 ± 1.27 months, 4.00 ± 1.76 months and 4.23 ± 1.63 months, respectively (P < 0.05). The dysphagia-free periods were comparable between the 3- and 5-min groups and were longer than those in the 1-min group. Muscle layer damage occurred in two patients (11.11%) in the 5-min group and in no patients in the other two groups. Conclusion: Three minutes was considered a safe and effective dilation duration for benign esophageal strictures after esophageal surgery or endoscopic submucosal dissection. [ABSTRACT FROM AUTHOR]

Introduction: Childbirth experience is an increasingly recognized and important measure of quality of obstetric care. Previous research has shown that it can be affected by intrapartum care and how labor is followed. A partograph is recommended to follow labor progression by recording cervical dilation over time. There are currently different guidelines in use worldwide to follow labor progression. The two main ones are the partograph recommended by the World Health Organization (WHO) based on the work of Friedman and Philpott and a guideline based on Zhang's research. In our study we assessed the effect of adhering to Zhang's guideline or the WHO partograph on childbirth experience. Zhang's guideline describes expected normal labor progression based on data from contemporary obstetric populations, resulting in an exponential progression curve, compared with the linear WHO partograph. The choice of labor curve affects the intrapartum follow‐up of women and this could potentially affect childbirth experience. Material and methods: The Labor Progression Study (LaPS) study was a prospective, cluster randomized controlled trial conducted at 14 birth centers in Norway. Birth centers were randomized to either follow Zhang's guideline or the WHO partograph. Nulliparous women in active labor, with one fetus in cephalic presentation at term and spontaneous labor onset were included. At 4 weeks postpartum, included women received an online login to complete the Childbirth Experience Questionnaire (CEQ). Total score on the CEQ, the four domain scores on the CEQ, and scores on the individual items on the CEQ were compared between the two groups. Results: There were 1855 women in the Zhang group and 1749 women in the WHO partograph group. There was no difference in the total or domain CEQ scores between the two groups. We found statistically significant differences for two individual items; women in the Zhang group scored lower on positive memories and feeling of control. Conclusions: Based on our findings on childbirth experience there is no reason to prefer Zhang's guideline over the WHO partograph. [ABSTRACT FROM AUTHOR]

Introduction: In this feasibility study, we hypothesize that the evaluation of cervical biomechanical strength can be improved if cervical length measurement is supplemented with quantitative elastography, which is a technique based on conventional ultrasound elastography combined with a force‐measuring device. Our aims were to: (a) develop a force‐measuring device; (b) introduce a cervical elastography index (CEI) and a cervical strength index (CSI; defined as cervical length × CEI); (c) evaluate how these indexes assess the cervical softening that takes place during normal pregnancy; and (d) how these indexes predict the cervical dilatation time from 4 to 10 cm. Material and methods: An electronic force‐measuring device was mounted on the handle of the transvaginal probe, allowing for force measurement when conducting elastography. The study group concerned with normal cervical softening included 44 unselected pregnant women. Outcomes were CEI and CSI at different gestational ages. The study group for labor induction included 26 singleton term pregnant women admitted for labor induction. Outcome was defined as cervical dilatation time from 4 to 10 cm. Elastography measured the changes in mean gray value (intensity) during manual compressions. Region of interest was set within the anterior cervical lip. Results: We found that the mean of all variables regarding cervical softening decreased from early to late pregnancy: ie cervical length from 34 to 29 mm, CEI from 0.17 to 0.11 N, and CSI from 5.9 to 3.1 N mm. Moreover, the cervical dilatation time during labor induction was associated with CEI, although not statistically significantly (area under the ROC curve of 0.67), but not with the Bishop score, the cervical length, or the CSI. Conclusions: We propose that quantitative elastography based on changes in the intensity of the B‐mode ultrasound recording, in combination with a force‐measuring device on the handle of the vaginal probe, deserves further investigation as an approach for evaluation of cervical biomechanical strength. [ABSTRACT FROM AUTHOR]

Introduction: The duration of labor and the immediate puerperium are affected by obstetric and maternal-fetal factors. Interventions to provide obstetric analgesia may prolong the hospital stay. Objective: To characterize the procedure for obstetric analgesia and describe the time elapsed between analgesia and delivery and postpartum surveillance in healthy mothers. Methods: Observational, descriptive trial. The time elapsed between analgesia and delivery, and postpartum surveillance were measured in healthy pregnant women with vaginal delivery and a prescription of a neuraxial analgesia technique. Results: 226 patients were included. The mean time elapsed between analgesia an delivery was 4 hours (IQR 3-7). 50.7 % (n = 114) received early analgesia (neuraxial technique with ≤ 4 centimeters of cervical dilatation), of which 48.2 % (n = 109) experienced a duration of analgesia until delivery longer than expected. The mean cervical dilatation at the time of the neuraxial approach was 4 centimeters (IQR 4-6) and the epidural technique was the most frequently used - 92.9 % (n = 210). The mean postpartum surveillance was 20 hours (IQR 15-27). Conclusions: Half of the patients included received early analgesia and around fifty percent of them took longer than expected in completing delivery. The postpartum surveillance time was consistent with the provisions of the Ministry of Health and with the current trend of a short postpartum surveillance aimed at early hospital discharge and the benefits thereof. [ABSTRACT FROM AUTHOR]

The authors propose a method for solving the game problem where the trajectory of a quasi-linear non-stationary system approaches a cylindrical terminal set varying with time. The case is considered where Pontryagin's condition (the condition of the first player's advantage) is not satisfied. A time dilation function is introduced, which postpones the time of game termination and is used to introduce a modified Pontryagin's condition, which allows making a measurable choice of control. The basic method is the method of resolving functions. Using the technique of set-valued mappings and their selectors, the strategies are generated, which guarantee the problem solution. The process of convergence of the trajectory and the terminal set consists of two sections: active and passive, where the control of the first player is selected using the control of the second player with a certain time delay, which depends on the time dilation function. The scheme of the method is outlined and sufficient conditions for the game termination in a finite time are obtained. [ABSTRACT FROM AUTHOR]

Coronary artery aneurysms (CAA) are a rare entity with an incidence of 0.3-5.3%. They are dilations of 1.5 times larger than normal adjacent artery, with the right coronary artery as the most affected vessel. Its pathophysiology is unclear but atherosclerosis is believed to be the main cause. CAA are generally asymptomatic but can cause coronary ischemia. Its treatment is yet to be established due to general ignorance about its nature. It ranges from conservative management to surgery. In the following text, we report a case of a patient with acute myocardial infarction presenting ST-segment elevation, who showed a right coronary artery aneurysm in coronary angiography. The patient required thrombectomy, angioplasty and subsequent lifetime outpatient medical management. [ABSTRACT FROM AUTHOR]

We review how the kinematic structures of special relativity and quantum mechanics both stem from the relativity principle, i.e., "no preferred reference frame" (NPRF). Essentially, NPRF applied to the measurement of the speed of light c gives the light postulate and leads to the geometry of Minkowski space, while NPRF applied to the measurement of Planck's constant h gives "average-only" projection and leads to the denumerable-dimensional Hilbert space of quantum mechanics. These kinematic structures contain the counterintuitive aspects ("mysteries") of time dilation, length contraction, and quantum entanglement. In this essay, we extend the application of NPRF to the gravitational constant G and show that it leads to the "mystery" of the contextuality of mass in general relativity. Thus, we see an underlying coherence and integrity in modern physics via its "mysteries" and the fundamental constants c, h, and G. It is well known that Minkowski and Einstein were greatly influenced by David Hilbert in their development of special relativity and general relativity, respectively, but relating those theories to quantum mechanics via its non-Boolean Hilbert space kinematics is perhaps surprising. [ABSTRACT FROM AUTHOR]

Objective: In order to improve the efficiency of treatment, this study compared catheter contact thrombolysis in patients with iliac vein compression syndrome and deep vein thrombosis at the same time as balloon dilatation + stent treatment plan and staged treatment plan. Methods: Sixty-five patients with iliac vein compression syndrome combined with deep vein thrombosis of the lower extremities were taken as the research objects. According to the treatment method, they were divided into study group and control group. Thirty-two patients in the study group received catheter-contact thrombolysis and balloon dilatation + stent therapy at the same time; 33 patients in the control group received catheter-contact thrombolysis and balloon dilatation+ stent therapy. The patient's thigh circumference, calf circumference, vascular patency score, surgical indicators (hospitalization time, hospitalization times, thrombolysis time and puncture times), complications (thrombosis recurrence, bleeding, and pulmonary embolism) and sequelae of deep vein thrombosis are used as indicators. Results: The thigh circumference, calf circumference and venous patency scores of the two groups of patients were not significantly different before treatment (P>0.05). After treatment, the thigh circumference, calf circumference and venous patency scores of the two groups were significantly improved (P<0.05). There was no significant difference in various indicators between the two (P>0.05). The length of hospitalization, the number of hospitalizations, the time of thrombolysis and the number of punctures in the study group were significantly lower than those in the control group (P<0.05). There were 0 cases of thrombosis recurrence in the study group and 4 cases of thrombosis recurrence in the control group (P＜0.05). There were 1 bleeding in the study group, 0 pulmonary embolism, 2 bleeding in the control group, and 0 pulmonary embolism. There was no significant difference in bleeding and pulmonary embolism between the two groups(P>0.05). The incidence of PTS in the study group was 6.25 %, which was significantly lower than 18.18 % in the control group (P<0.05). Conclusions: Catheter contact thrombolysis at the same time balloon dilatation + stent treatment program has a good effect on iliac vein compression syndrome with deep vein thrombosis of lower limbs. [ABSTRACT FROM AUTHOR]

In ureterorenoscopy, anaesthesiologists are preferring regional anaesthesia to avoid postoperative complications, while surgeons are preferring general anaesthesia to avoid ureteral trauma. China has not published its guidelines and not referring to the European Association of Urology guidelines. The objectives of study were to evaluate the effects of general, spinal, and epidural anaesthesia on ureter access and surgical outcomes of ureterorenoscopy. Charts of a total of 392 patients with the American Society of Anaesthesiologists grade I or II, and underwent flexible ureterorenoscopy for removal of the proximal, middle, or distal ureteral single stone under general anaesthesia (GA group; n = 145) or spinal anaesthesia (SA group; n = 131) or epidural anaesthesia (EA group; n = 116) were reviewed retrospectively. The dilatation time for patients of GA group was fewer than those of SA (104.01 ± 12.77 sec/patient vs. 130.55 ± 22.53 sec/patient, p <.0001, q = 17.0350) and EA (104.01 ± 12.77 sec/patient vs. 147.03 ± 18.76 sec/patient, p <.0001, q = 26.7240) groups. The time to reach to stone for patients of GA group was fewer than those of SA (126.68 ± 12.59 sec/patient vs. 137.60 ± 17.84 sec/patient, p <.0001, q = 8.4510) and EA (126.68 ± 12.59 sec/patient vs. 149.44 ± 14.85 sec/patient, p <.0001, q = 17.0350) groups. The lithotripsy time (p =.359), operation time (p =.449), intraoperative complications (p =.058), and length of hospital stays (p =.057) of patients were same among groups. Visual analog scale pain scores of patients of the GA group found higher among groups. General anaesthesia caused nausea and vomiting. This study suggests general anaesthesia for flexible ureterorenoscopy if there is no contraindication. General anaesthesia facilitates early dilatation of ureters and access to the stone. No strong correlation of the anaesthesia method of choice with lithotripsy time, operation time, intraoperative complications, stone-free conditions, and length of hospital stays. Epidural and spinal anaesthesia have advantages of fewer postoperative pain and better postoperative outcomes for flexible ureterorenoscopy. [ABSTRACT FROM AUTHOR]

Kaluza was the first to realize that the four-dimensional gravitational field of general relativity and the classical electromagnetic field behave as if they were components of a five-dimensional gravitational field. We present a novel experimental test of the macroscopic classical interpretation of the Kaluza fifth dimension. Our experiment design probes a key feature of Kaluza unification—that electric charge is identified with motion in the fifth dimension. Therefore, we tested for a time dilation effect on an electrically charged clock. This test can also be understood as a constraint on time dilation from a constant electric potential of any origin. This is only the second such test of time dilation under electric charge reported in the literature, and a null result was obtained here. We introduce the concept of a charged clock in the Kaluza context, and discuss some ambiguities in its interpretation. We conclude that a classical, macroscopic interpretation of the Kaluza fifth dimension may require a timelike signature in the five-dimensional metric, and the associated absence of a rest frame along the fifth coordinate.

It is known that very distant galaxies, much like our own, show remarkably high receding velocities, the magnitude of which increases with distance. Therefore, in this study, a gravitational analog of the photoelectric effect was investigated by replacing the classical (wave) theory of gravity with a gravity quanta hypothesis. The significance of this concept regarding the motion of distant galaxies is evaluated by comparing the results obtained for a photon traveling through a Planck lattice model of spacetime to the observational data for both the cosmological redshift and time dilation effects of light from distant Type Ia supernovae. The photogravity effect does not necessarily invalidate the standard big bang cosmology and may in fact add a layer of fidelity to its conclusions concerning the evolution and age of the universe.

Inseparable realities result from the previous falsification of relativity and replacement of spacetime in two papers that (1) were previously published in this journal and (2) followed Einstein's 1954 speculations it is possible physics is based on a discontinuum theory, and the continuum concept along with space and time must be discarded. Using Einstein's equivalency strategy, a vacuum state with a zero net total energy and absolute-nothing are demonstrated to be equivalent. Einstein's general relativity must be replaced, because it was falsified by the first paper previously published in this journal and, in addition, it is a generalization of a falsified theory (i.e., special relativity).VC 2022 Physics Essays Publication. [ABSTRACT FROM AUTHOR]

Background: Postoperative dysphagia after anti-reflux surgery typically resolves in a few weeks. However, even after the initial swelling has resolved at 6 weeks, dysphagia can persist in 30% of patients necessitating esophageal dilation. The purpose of this study was to investigate the effect of esophageal dilation on postoperative dysphagia, the recurrence of reflux symptoms, and the efficacy of pneumatic dilations on postoperative dysphagia. Methods: A prospectively collected database was reviewed for patients who underwent partial/complete fundoplication with/without paraesophageal hernia repair between 2006 and 2014. Patient age, sex, BMI, DeMeester score, procedure type, procedure duration, length of stay, postoperative dysphagia, time to first pneumatic dilation, number of dilations, and the need for reoperations were collected. Results: The study included 902 consecutive patients, 71.3% females, with a mean age of 57.8 ± 14.7 years. Postoperative dysphagia was noted in 26.3% of patients, of whom 89% had complete fundoplication (p < 0.01). Endoscopic dilation was performed in 93 patients (10.3%) with 59 (63.4%) demonstrating persistent dysphagia. Recurrent reflux symptoms occurred in 35 (37.6%) patients who underwent endoscopic dilation. Patients who underwent a dilation for symptoms of dysphagia were less likely to require a revisional surgery later than patients who had dysphagia but did not undergo a dilation before revisional surgery (17.2% vs 41.7%, respectively, p < 0.001) in the 4-year follow-up period. The duration of initial dilation from surgery was inversely related to the need for revisional surgery (p = 0.047), while more than one dilation was not associated with additive benefit. Conclusion: One attempt at endoscopic dilation of the esophagogastric fundoplication may provide relief in patients with postoperative dysphagia and can be used as a predictive factor for the need of revision. However, there is an increased risk for recurrent reflux symptoms and revisional surgery may ultimately be indicated for control of symptoms. [ABSTRACT FROM AUTHOR]

Background: In infants with congenital oesophageal atresia, anastomotic stenosis easily occurs after one-stage oesophageal anastomosis, leading to dysphagia. In severe cases, oesophageal dilatation is required. In this paper, the timing of oesophageal dilatation in infants with anastomotic stenosis was investigated through retrospective data analysis.Methods: The clinical data of 107 infants with oesophageal atresia who underwent one-stage anastomosis in our hospital from January 2015 to December 2018 were retrospectively analysed. Data such as the timing and frequency of oesophageal dilatation under gastroscopy after surgery were collected to analyse the timing of oesophageal dilatation in infants with different risk factors.Results: For infants with refractory stenosis, the average number of dilatations in the early dilatation group (the first dilatation was performed within 6 months after the surgery) was 5.75 ± 0.5, which was higher than the average of 7.40 ± 1.35 times in the normal dilatation group (the first dilatation was performed 6 months after the surgery), P = 0.038. For the infants with anastomotic fistula and anastomotic stenosis, the number of oesophageal dilatations in the early dilatation group was 2.58 ± 2.02 times, which was less than the 6.38 ± 2.06 times in the normal dilatation group, P = 0.001. For infants with non-anastomotic fistula stenosis, early oesophageal dilatation could not reduce the total number of oesophageal dilatations.Conclusion: Starting to perform oesophageal dilatation within 6 months after one-stage anastomosis for congenital oesophageal atresia can reduce the required number of dilatations in infants with postoperative anastomotic fistula and refractory anastomotic stenosis. [ABSTRACT FROM AUTHOR]

This article considers how changing screen practices are changing prevailing domestic temporal routines to generate new household dynamics. Underpinned by a case study of the multiscreen home, a media time approach offers a close analysis of the temporal dimensions of household screen use. The analysis draws on data about patterns of use of screen devices and streaming services from UK's communications regulator Ofcom, combined with findings from qualitative studies of media time and second-screen uses. Explaining that second screens offer new kinds of connectivity within home, the study queries assumptions of time erosion and temporal fragmentation. The article proposes that second screens afford new temporal experiences and interactions signifying a new domestic screen culture characterised by time dilation. Digital screen relations operate within polymediated timescapes enabling an opening up and extension of time to produce new domestic screen cultures distinguished as intra-domestic and trans-domestic screen time. [ABSTRACT FROM AUTHOR]

Objective: Documentation of middle ear pressure at different stages of balloon Eustachian tuboplasty and assessing risk of barotrauma with this procedure. Main outcome measures: Middle ear pressure measurements in patients undergoing balloon Eustachian tuboplasty at the time of pre‐insertion, catheter insertion, inflation, one minute post inflation, deflation, and catheter withdrawal, as well as documentation of pressure change in the middle ear between different stages. Results: A total of 24 patients and 45 Eustachian tubes, 11 females and 13 males, with an average age of 55.6 years were included in this study. Middle ear pressure values during the active stages of the procedure varied from −356 to +159 daPa. The overall greatest negative pressure change measured was −515 daPa from catheter insertion to immediately post balloon inflation. The overall greatest positive pressure change measured was +418 daPa from immediate catheter inflation to one minute post inflation. Conclusions: There was no consistent pattern of middle ear pressure change noted during the different stages of balloon Eustachian tuboplasty as both positive and negative middle ear pressure changes were noted at the time of balloon dilation. Dangerous levels of middle ear pressure raising concern for barotrauma were not identified during the procedure. Level of evidence: Level IV. [ABSTRACT FROM AUTHOR]

In this paper, we study the phenomenon of quantum interference in the presence of external gravitational fields described by alternative theories of gravity. We analyze both non-relativistic and relativistic effects induced by the underlying curved background on a superposed quantum system. In the non-relativistic regime, it is possible to come across a gravitational counterpart of the Bohm–Aharonov effect, which results in a phase shift proportional to the derivative of the modified Newtonian potential. On the other hand, beyond the Newtonian approximation, the relativistic nature of gravity plays a crucial rôle. Indeed, the existence of a gravitational time dilation between the two arms of the interferometer causes a loss of coherence that is in principle observable in quantum interference patterns. We work in the context of generalized quadratic theories of gravity to compare their physical predictions with the analogous outcomes in general relativity. In so doing, we show that the decoherence rate strongly depends on the gravitational model under investigation, which means that this approach turns out to be a promising test bench to probe and discriminate among all the extensions of Einstein's theory in future experiments. [ABSTRACT FROM AUTHOR]

We investigate the advantage of coherent superposition of two different coded channels in quantum metrology. In a continuous variable system, we show that the Heisenberg limit 1/N can be beaten by the coherent superposition without the help of indefinite causal order. And in parameter estimation, we demonstrate that the strategy with the coherent superposition can perform better than the strategy with quantum switch which can generate indefinite causal order. We analytically obtain the general form of estimation precision in terms of the quantum Fisher information and further prove that the nonlinear Hamiltonian can improve the estimation precision and make the measurement uncertainty scale as 1/Nm for m ≥ 2. Our results can help to construct a high-precision measurement equipment, which can be applied to the detection of coupling strength and the test of time dilation and the modification of the canonical commutation relation. [ABSTRACT FROM AUTHOR]

On Earth, we always measure the constant velocity c of electromagnetic radiation. Einstein assumed the velocity c of light to be constant in all inertial frames and developed his theory of special relativity by considering a light beam that moves back and forth, whereby he derived transformations between the coordinates of two reference frames: A moving reference frame represented by the coordinate system k and the coordinate system K that is at rest with respect to k. However, by applying Einstein's theory of relativity, with its postulates of relativistic time dilation and length contraction, to electromagnetic radiation that moves only in one direction, either in the direction of or in the opposite direction to a moving inertial frame, it is demonstrated that the constancy of the velocity c of light is not compatible with Einstein's theory of special relativity. It becomes obvious that Einstein's relativistic physics must be an unrealistic theory, and consequently, we need an alternative, nonrelativistic, explanation of the constancy of the velocity c of electromagnetic radiation measured on Earth, and for the special and general "relativistic" phenomena. [ABSTRACT FROM AUTHOR]

The colour-word Stroop task produces both information conflict (detection of the ink colour vs word meaning) and task conflict (respond to the ink colour vs read the word). In this study, we measured both reaction time and pupil dilation, and the neutral stimuli in our study were non-readable letter strings as well as meaningless non-readable stimuli (i.e., coloured patches and abstract character strings). Our results showed slowest responses in the incongruent trials and fastest responses in the congruent trials. However, no differences were found between the investigated neutrals. In contrast, pupil dilation was largest in the incongruent trials and smallest in the neutral trials. Moreover, the more the neutral stimuli were meaningless, the less the pupil dilation that was observed. Our results suggest that non-word meaningless stimuli reduced task conflict (compared with all the investigated conditions). Neutral equivalence should be taken into consideration in Stroop and Stroop-like tasks. [ABSTRACT FROM AUTHOR]

Background: The magnetic sphincter augmentation device (MSA) provides effective relief of gastroesophageal reflux symptoms. Dysphagia after MSA implantation sometimes prompts endoscopic dilation. The manufacturer's instructions are that it be performed 6 or more weeks after implantation under fluoroscopic guidance to not more than 15 mm keeping 3 or more beads closed. The purpose of this study was to assess adherence to these recommendations and explore the techniques used and outcomes after MSA dilation. Methods and procedures: We conducted a multicenter retrospective review of patients undergoing dilation for dysphagia after MSA placement from 2012 to 2018. Results: A total of 144 patients underwent 245 dilations. The median size of MSA placed was 14 beads (range 12–17) and the median time to dilation was 175 days. A second dilation was performed in 67 patients, 22 patients had a third dilation and 7 patients underwent 4 or more dilations. In total, 17 devices (11.8%) were eventually explanted. The majority of dilations were performed with a balloon dilator (81%). The median dilator size was 18 mm and 73.4% were done with a dilator larger than 15 mm. There was no association between dilator size and need for subsequent dilation. Fluoroscopy was used in 28% of cases. There were no perforations or device erosions related to dilation. Discussion: There is no clinical credence to the manufacturer's recommendation for the use of fluoroscopy and limitation to 15 mm when dilating a patient for dysphagia after MSA implantation. Use of a larger size dilator was not associated with perforation or device erosion, but also did not reduce the need for repeat dilation. Given this, we would recommend that the initial dilation for any size MSA device be done using a 15 mm through-the-scope balloon dilator. Dysphagia prompting dilation after MSA implantation is associated with nearly a 12% risk of device explantation. [ABSTRACT FROM AUTHOR]

Rotational transformations describe relativistic effects in rotating frames. There are four major kinematic rotational transformations: the Langevin metric; Post transformation; Franklin transformation; and the rotational form of the absolute Lorentz transformation. The four transformations exhibit different combinations of relativistic effects and simultaneity frameworks, and generate different predictions for relativistic phenomena. Here, the predictions of the four rotational transformations are compared with recent optical data that has sufficient resolution to distinguish the transformations. We show that the rotational absolute Lorentz transformation matches diverse relativistic optical and nonoptical rotational data. These include experimental observations of length contraction, directional time dilation, anisotropic one-way speed of light, isotropic two-way speed of light, and the conventional Sagnac effect. In contrast, the other three transformations do not match the full range of rotating-frame relativistic observations. [ABSTRACT FROM AUTHOR]

Esophageal strictures commonly cause dysphagia and require treatment with endoscopic dilation using balloons or bougies. We aimed to determine whether biopsy forceps disruption of strictures at time of dilation increases time to repeat intervention or duration of intervention-free follow-up. We performed a retrospective analysis of 289 adults (age 61.0 ± 0.8 years, 66.4% female) who underwent dilation of an esophageal stricture at our tertiary care center between 2014 and 2016. Exclusions consisted of endoscopic intervention within the preceding 6 months, prior foregut neoplasia, achalasia, radiofrequency ablation, endoscopic mucosal resection, endoscopic submucosal dissection, or foregut surgery. Demographics, clinical presentation, dilation technique, and follow-up were abstracted from electronic medical records. We compared time to repeat dilation and duration of intervention-free follow-up between treatment subgroups. Balloon dilation was performed more often than bougie dilation (76.8 vs. 17.6%); biopsy forceps disruption was performed in 23.2%. Over a median follow-up of 52.9 months, 135 patients (46.7%) underwent repeat dilation. Age, body mass index, gender, and use of antisecretory medications did not influence need for repeat dilation (P  = ns for each). Bougie dilation with biopsy forceps disruption prolonged time to repeat dilation in all patients (P  ≤ 0.02), particularly in those with gastroesophageal reflux disease (P  ≤ 0.03), compared with bougie dilation alone and balloon dilation with or without disruption. On Kaplan–Meier analysis, bougie dilation with biopsy forceps resulted in longer intervention-free follow-up compared with dilation alone (P  = 0.03). We conclude that stricture disruption with biopsy forceps increases time to repeat intervention with bougie but not balloon dilation. [ABSTRACT FROM AUTHOR]