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This essay weaves together elements of the concepts of spacetime, demons and the U.S. popular culture concept of demon time to postulate the end of the world and bring a conclusion to white supremacist and anti-African American worlds. Topics discussed are Black posthumanism as the foundation of Black transhumanism or technological materialization, time dilation as an element for understanding how African Americans experience time, and demon time as a way to bring African American realities.

Discrete event simulation has been widely applied to study the behavior of stochastic manufacturing systems. This is due to the fact that manufacturing systems are usually too complex to obtain a closed-form analytical model that can accurately predict their performance. This becomes particularly critical when the optimization of these systems is of concern. In fact, Simulation optimization techniques are employed to identify the manufacturing system configuration which can maximize the expected system performance when this can only be estimated by running a simulator. In this article, we look into simulation-based optimization when a finite number of solutions are available and we have to identify the best. In particular, we propose, for the first time, the integration of Optimal Computing Budget Allocation (OCBA), which is based on independent measures from each simulation experiment, and Time Dilation (TD), which is a single-run simulation optimization algorithm. As a result, the optimization problem is solved when only one experiment of the system is performed by changing the "speed" of the simulation at each configuration in order to control the computational effort. The challenge is how to iteratively select such a speed. We solve this problem by proposing TD-OCBA, which integrates TD and OCBA while relying on standardized time series variance estimators. Numerical experiments have been conducted to study the performance of the algorithm when the response is generated from a time series. This provides the possibility to test the robustness of TD-OCBA. Comparison between TD-OCBA and the original TD method was performed by simulating a job shop system reported in the literature. Finally, an application involving semiconductors remote diagnostics is used to compare the TD-OCBA method and what is known as the equal allocation method. [ABSTRACT FROM AUTHOR]

A review of 24 experiments investigated the factors that produce a subjective time dilation. The aim of this review was to investigate the magnitude of the obtained time dilation. The mean time duration judgment ratio of subjective time to objective time for the selected studies was 1.31, SD = .24. The analyses revealed that experimental studies investigating subjective time dilation tend to obtain small to moderate time dilation and that several factors can be manipulated in order to make a specific time interval appear longer than it is. Highlighting the factors that lead to a subjective time dilation has both research implications, by pointing to the underlying cognitive mechanisms of time perception, and practical implications, by indicating the factors that can be manipulated in order to control how we perceive time. [ABSTRACT FROM AUTHOR]

Generalized Doppler shift for light is derived by considering both velocity and acceleration, and is used to calculate time dilation ratio. A circular mirror used to measure time is transformed to the elliptical mirror in a reference frame when it is in motion. The special relativistic Doppler shift is calculated in any propagation direction of light for a constant velocity of motion. Furthermore, the generalized Doppler shift is derived by considering both the velocity and the acceleration effect. The ratio of the frequency shifts are shown as a function of velocity, acceleration, and detection angle. [ABSTRACT FROM PUBLISHER]

The aim of this study was to determine whether the dopamine agonist (DA) drug cabergoline used in the treatment of prolactinoma causes autonomic dysfunction by measuring static and dynamic pupillary responses. The study included 25 eyes from 25 patients who were receiving DA for the treatment of prolactinoma and 25 eyes from 25 healthy individuals. Static and dynamic pupillary responses were measured by automatic quantitative pupillometry. The scotopic pupillary diameter was found to be significantly higher in patients receiving DA medication compared with the control group, while pupil contraction time and pupillary dilatation latency were significantly lower. DA drug use changes static and dynamic pupillary responses, probably by increasing sympathetic tone. Pupillometry can be used as a non-invasive method to provide information about changes in the autonomic nervous system in patients receiving such drug therapy. [ABSTRACT FROM AUTHOR]

The 'innovation paradox' refers to the coexistence in the West over the last five decades of a steady decrease in the growth of productivity with the increase in the quantity of available information. These trends, which started with the invention of the internet, call for revisiting mainstream endogenous growth theory in an age dominated by information and communication technology. The weakness of the arguments used to justify the paradox, the unorthodox comparison with China and the history of the industrial revolutions point to the technological obsolescence of liberal democracy as the real explanation for the paradox. A debate on how to adapt Western institutions to a radically new context is launched. [ABSTRACT FROM AUTHOR]

During pregnancy, the stiffness of the cervical tissue decreases long before the cervical length decreases. Therefore, several approaches have been proposed in order to ensure a more objective assessment of cervical stiffness than that achieved by digital evaluation. Strain elastography has shown promising results. This technique is based on an ultrasound assessment of the tissue deformation that occurs when the examiner applies pressure on the tissue with the ultrasound probe. However, the results are only semi-quantitative as they depend on the unmeasured force used by the examiner. We, therefore, hypothesized that a force-measuring device applied to the handle of the ultrasound probe may render the technique quantitative. With this approach, the stiffness is the force (measured by the device) divided by the compression (measured by the elastography platform). One perspective is the early identification of women at risk of preterm birth in whom cervical stiffness may decrease long before cervical shortening. Another perspective is cervical evaluation when planning labor induction. In this feasibility study, we aimed to evaluate how quantitative strain elastography performs when a commercially available strain elastography platform (by which the algorithm is unavailable) is combined with a custom-made, force-measuring device. We studied how the assessments were associated with the gestational age in women with uncomplicated pregnancies and how they were associated with cervical dilatation time from 4 to 10 cm in women undergoing labor induction. In the analysis, we included quantitative strain elastography assessments from 47 women with uncomplicated singleton pregnancies, with gestational age between 12+0 and 40+0, and from 27 singleton term-pregnant women undergoing labor induction. The force-measuring device was mounted on the handle of a transvaginal probe. The strain values (i.e. the compression of the cervical tissue) were obtained by the elastography software of the ultrasound scanner (GE Voluson E10). The region of interest was placed within the central part of the anterior cervical lip. Based on the force data and strain values, we calculated the outcomes cervical elastography indexGE (CEIGE) and the cervical strength indexGE (CEIGE x cervical length: CSIGE). The average CEIGE was 0.24 N at week 12 and 0.15 N at week 30–34. For CSIGE these figures were 8.2 and 4.7 N mm, respectively (p = 0.002). Among women undergoing labor induction, the CEIGE was associated with a cervical dilatation time (4–10 cm) beyond 7 h. For nulliparous women, this area under the ROC curve was 0.94. Quantitative strain elastography may constitute a tool for the evaluation of a uterine cervix with normal length in women at risk of preterm birth and in women undergoing labor induction. The performance of this tool deserves evaluation in larger clinical trials. [ABSTRACT FROM AUTHOR]

An impaction of the foetal head at caesarean section is a topical concern in modern obstetric practice. The management options for this problem are well described but the incidence or even definition of impaction, is unknown. The primary aim of this study was to ascertain the incidence of impacted foetal head at CS in labour. This prospective study used data from all women undergoing CS during a 12-month period in a single unit. Following completion of all CS, the surgeon completed a questionnaire covering: cervical dilation at time of CS; if the surgeon felt there was a difficulty in delivering the foetal head as an indicator of impaction, as well as the other techniques utilised. Of 440 EMCS in labour, 18% (n = 81) reported a difficulty delivering the head, which was most common at cervical dilation ≥8 cm (n = 124, 48%). A difficulty with the delivery of the foetal head was associated with 36% increased measured blood loss. Impact statement What is already known on this subject? Impaction of the foetal head at a caesarean section is a recognised complication of CS in late labour but there are no reliable data on the incidence of the problem. It is poorly defined and yet many techniques and devices have been described to overcome this problem, however, optimal management remains uncertain. What do the results of this study add? The primary aim of this study was to determine the incidence of the impacted foetal head during CS in labour as determined by whether the surgeon experienced difficulty with delivery of the head. We report that at least some difficulty in delivering the foetal head at CS is common, and most often encountered when cervical dilation is ≥8 cm. When additional manoeuvres were required, the 'push' technique was exclusively adopted with implications for training. A difficulty in delivering the foetal head was associated with a 36% increase in the measured maternal blood loss. What are the implications of these findings for clinical practice and/or further research? Further multi-centre investigation is required to ascertain incidence of this obstetric problem with predicting factors determined. This work will inform decisions about the optimal management. [ABSTRACT FROM AUTHOR]

Premixed turbulent flames feature strong interactions between chemical reactions and turbulence that affect scalar and turbulence statistics. The focus of the present work is on clarifying the impact of pressure dilatation/flamelet scrambling effects with a comprehensive second-moment closure used for evaluation purposes. Model extensions that take into account flamelet orientation and molecular diffusion are derived. Isothermal pressure transport is included with an additional variable density contribution derived for the flamelet regime of combustion. Full closure is assessed by comparisons with Direct Numerical Simulations (DNSs) of statistically ‘steady’ fully developed premixed turbulent planar flames at different expansion ratios. Subsequently, the prediction of lean premixed turbulent methane–air flames featuring fractal grid generated turbulence in an opposed jet geometry is considered. The overall agreement shows that ‘dilatation’ effects contribute to counter-gradient transport and can also increase the turbulent kinetic energy significantly. Levels of anisotropy are broadly consistent with the DNS data and key aspects of opposed jet flames are well predicted. However, it is also shown that complications arise due to interactions between the imposed pressure gradient and combustion and that redistribution is affected along with the scalar flux at the leading edge. The latter is strongly affected by the reaction rate closure and, potentially, by pressure transport. Overall, the derived models offer significant improvements and can readily be applied to the modelling of premixed turbulent flames at practical rates of heat release. [ABSTRACT FROM PUBLISHER]

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]

This was six years after the publication of Einstein's special theory of relativity, but several years before the general theory, and in his book he includes Langevin's original account in English translation. Benguigui himself is strongly of the opinion that the acceleration must be involved, and that this involves considerations of general relativity. The author of the present book, Lucien Benguigui, recounts this and traces the original tale back to a talk by the French physicist Paul Langevin in 1911. There are few topics in physics that have excited so many different contrary opinions as Einstein's so-called "Twin Paradox", otherwise known as the "Clock Paradox". [Extracted from the article]

Background: 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. Methods: 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. Results: 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. Conclusions: This study suggests general anaesthesia for flexible ureterorenoscopy if there is no contraindication. [ABSTRACT FROM AUTHOR]

Esophageal perforation is the most serious complication of pneumatic dilation for achalasia and is traditionally managed by conservative therapy or surgical repair. We present four achalasia patients who underwent pneumatic dilatation, complicated by an esophageal perforation. All patients were treated successfully with endoscopic treatment: two patients with Eso-SPONGE® vacuum therapy, in the other two patients, esophageal defects were closed endoscopically using Endoclips. The time between dilatation and detection of the perforation was less than 24 h in all cases. Non-surgical treatment resulted in a relatively short hospital stay, ranging from 5 to 10 days, and an uneventful recovery in all patients. Based on our experience, endoscopic clipping and/or vacuum therapy are relatively new, valuable, minimally invasive techniques in the management of patients with small, well-defined esophageal tears with contained leakage and should be considered as primary therapeutic option for iatrogenic perforation in achalasia. [ABSTRACT FROM AUTHOR]

Presents topics that may be isolated for a problem set, applications unit or discussion in a calculus or differential equations course concerning the special theory of relativity. Summary of curves in the Euclidean, Galilean and Minkowskian planes; Examples of time dilation; How to define the coordinate system of a moving observer with space-time path.

Background: Preterm birth is a major cause of neonatal morbidity and mortality in the USA. In many patients at risk for preterm birth, cervical length (CL) screening is used to guide decisions regarding cerclage placement. Quality evidence shows that cerclage prolongs pregnancy in high-risk women with a short CL in women with a history of preterm birth and in women with painless cervical dilation in the second trimester, though the degree of cervical shortening, dilation, or gestational age at cerclage placement are not consistently associated with the subsequent rate of preterm birth. Our objective was to determine if cervical length (CL), cervical dilation or gestational age (GA) at the time of cerclage placement are associated with preterm birth among women undergoing ultrasound-indicated or exam-indicated cerclage.Study design: This was a retrospective cohort study of all patients with a singleton pregnancy who underwent ultrasound-indicated or exam-indicated Shirodkar cerclage placement at a single maternal-fetal medicine practice in New York City between November 2005 and May 2017. All patients included in the study had previously undergone CL screening for an increased risk of preterm birth (for example, prior spontaneous preterm birth or mid-trimester loss, prior cervical excision). The cervical length or dilation and GA at the time of cerclage placement were collected, as were demographic and obstetric outcome data for the current pregnancy. The primary outcome was delivery <36 or ≥36 weeks. Planned subgroup analyses of the primary outcome were performed based on CL at the time of ultrasound-indicated cerclage (0-9 mm, 10-19 mm, ≥20 mm), cervical dilation at the time of physical exam-indicated cerclage (<2 cm vs. ≥2 cm), and gestational age at cerclage placement (<20 weeks vs. ≥20 weeks). Data were analyzed using the Student's t-test and chi-square test for trend.Results: There were 123 and 39 patients in the ultrasound- and exam-indicated cerclage groups, respectively. Twenty six (21.2%) patients in the ultrasound-indicated subgroup and 24 patients (61.5%) in the exam-indicated subgroup delivered <36 weeks. CL (16.4 versus 17.6 mm, p = .28) and GA (19.7 versus 20.0 weeks, p = .58) at the time of ultrasound-indicated cerclage placement were not significantly different in patients who delivered <36 and ≥36 weeks' gestation, respectively. Women with cervical dilation ≥2 cm prior to exam-indicated cerclage placement were significantly more likely to deliver <36 weeks when compared to women with cervical dilation <2 cm (77.8 versus 47.6%, p = .05); however, there were no significant differences in rates of preterm birth <28 and <32 weeks between these two groups (38.9 versus 23.8%, p = .31 and 50.0% versus 28.6%, p = .17, respectively).Conclusions: Cervical length and GA at the time of ultrasound-indicated Shirodkar cerclage placement do not appear to impact the likelihood of preterm birth <36 weeks, while cervical dilation ≥2 cm at the time of exam-indicated Shirodkar cerclage is associated with an increased rate of preterm birth <36 weeks, but not earlier gestational ages at delivery. [ABSTRACT FROM AUTHOR]

Aim: To investigate regarding the safety and effectiveness of a balloon catheter (Aqueduct-100 device) to dilate the uterine cervix before operative hysteroscopies. Secondary objectives were to evaluate the duration of the dilatation procedure and to investigate on physicians' satisfaction with the device. Methods: Fifty women younger than 40 years, wishing pregnancies and diagnosed with apparently benign intrauterine lesions and/or uterine anomalies, were enrolled into this study and submitted to cervical priming with Aqueduct-100 device before operative hysteroscopy. Results: Initial cervical dilatation was ≤4 mm in all but one patient. Adequate (10 mm) cervical dilatation was achieved in only one patient, the remaining forty-nine needed additional cervical dilatation. All women, however, presented with a ≥6 mm cervical width after balloon catheter removal. The mean time to final cervical dilatation was 8.5 minutes. No perioperative complications occurred. Physicians reported, in the majority of cases, satisfaction for the dilatation achieved (66%), the ease of balloon catheter insertion/use (82%), and for the ease of additional dilatation (96%). Conclusions: Aqueduct-100 device before operative hysteroscopy is safe and useful to increase the baseline cervical width and facilitate additional dilatation, with good effects on physician satisfaction and acceptable dilatation times. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to determine whether cervical ripening with misoprostol (MP) is associated with higher rates of cesarean delivery (CD) compared with dinoprostone (DP) or Pitocin/Foley balloon (PFB) in infants found to be small for gestational age (SGA). Study design: Single center institution based cohort study of all inductions between 2008 and 2012 where birth weight was found to be as SGA (< 10th percentile). Maternal demographic, obstetric, and labor characteristics were compared between SGA births where cervical ripening with MP, DP, or PFB was used as the primary agent. The primary outcome was CD after attempted induction between the three study groups which included MP, DP, and PFB. Secondary outcomes included inability to achieve active labor (defined as cervical dilation of 6 cm or greater), cervical dilation at the time of CD, the incidence of CD for the indication of non-reassuring fetal status, and neonatal outcomes including Apgar scores and admission to neonatal intensive care unit. Multivariable logistic regression was performed to evaluate the association of these outcomes with MP as the induction agent versus the referent groups, PFB. Results: Of 260 inductions where the infant was found to be SGA by birth weight during the 5-year period, 172 (66.2%) patients were induced using MP, 38 (14.6%) with DP, and 50 (19.2%) with PFB. There were no differences in baseline characteristics between groups (age, race, BMI, parity, induction indication, birth weights, or maternal comorbidities). MP did not increase rate of CD which was 25.6%, 26.3%, and 22.0% in the MP, DP, and PFB groups, respectively (p = .86). There were also no differences in incidence of CD for non-reassuring fetal well-being (NRFWB), failure to attain active labor, or cervical dilation at time of CD between induction groups. NICU admission was 18%, 18%, and 16% (p = .94) between MP, DP, and PFB groups, respectively. MP was not associated with an increased rate of CD when compared with the other two agents combined, aOR 0.93 (0.67-1.30, 95% CI). Conclusion: MP appears to have similar efficacy and safety when compared with other cervical ripening agents in pregnancies complicated by SGA. [ABSTRACT FROM AUTHOR]

In the interwar period there was a significant school of thought that repudiated Einstein's theory of relativity on the grounds that it contained elementary inconsistencies. Some of these critics held extreme right-wing and anti-Semitic views, and this has tended to discredit their technical objections to relativity as being scientifically shallow. This paper investigates an alternative possibility: that the critics were right and that the success of Einstein's theory in overcoming them was due to its strengths as an ideology rather than as a science. The clock paradox illustrates how relativity theory does indeed contain inconsistencies that make it scientifically problematic. These same inconsistencies, however, make the theory ideologically powerful. The implications of this argument are examined with respect to Thomas Kuhn and Karl Popper's accounts of the philosophy of science. [ABSTRACT FROM AUTHOR]

Presents a study which analyzed the closed universe twin paradox. Spacetime diagram which combined the spatial and temporal information; Comparison of Euclidian geometry with the geometry of spacetime.

This paper has a pedagogical aim. Indeed, by using the relativistic velocity-addition and Einstein's equivalence principle (EEP), we want to analyse in a simple way the physics of time on a rotating non-inertial frame. We use a didactic approach considering four friends. The first is in the laboratory, the second at rest on the disk at radius r, the third and fourth ride a bicycle in opposite directions but with the same speed with respect to the platform. Since, in General Relativity, time can flow differently at every point, the concept of speed is often ambiguous. [ABSTRACT FROM AUTHOR]

Paradox intrigues both mathematicians and artists of all kinds. Throughout the recorded history of human thought, paradox has been a signal that we have to look hard for explanations, whether in natural language or the symbols of math and logic. The particular resonance between math and poetry is related to the fact that paradoxical concepts can translate from one form of expression to another surprisingly well. I examine paradoxes that have intrigued me and present five poems that have been inspired as a result. [ABSTRACT FROM PUBLISHER]

Objective. To examine the necessity of routine cervical dilatation during elective cesarean delivery (ECD). Material and methods. A retrospective cohort study including all ECD during 2005 was performed, comparing post operative complications between patients with and without cervical dilatation. Results. Out of 666 ECD, 348 underwent routine cervical dilatation. No significant differences were found between the cervical dilatation and the comparison group regarding postpartum febrile morbidity (5.1 and 3.1%, respectively; p = 0.071), hospitalisation duration (4.1 ± 1.4 and 4.1 ± 2.0 days; p = 0.95), wound infection (0.9% and 1.25%, p = 0.451) or anemia rate (9.50 ± 0.73 and 9.54 ± 0.65, p = 0.91). Nevertheless, among patients following a previous vaginal delivery, cervical dilatation was significantly associated with post-operative fever (OR = 5.8; 95%CI 1.2-38.0; p = 0.021). Conclusion. Routine cervical dilatation during ECD does not reduce post operative morbidity. Moreover, among patients with a previous vaginal delivery cervical dilatation is a risk factor for febrile morbidity. [ABSTRACT FROM AUTHOR]

Choledochal cysts (CDCs) identified during the prenatal or immediate postnatal period are unusual with a majority being identified in older children and adults. Although authors advocate surgical resection of these presumed CDCs with reconstruction, there has been no agreement on the optimal timing of such an intervention when the initial diagnosis of CDC is made prenatally or during the newborn period. We present the cases of three children with biliary ductal dilation who were presumed to have CDC by ultrasound and/or magnetic resonance imaging during the perinatal period and who ultimately required different approaches to treatment. The eventual findings in these cases support a period of close postnatal observation followed by carefully planned individualised therapy. [ABSTRACT FROM AUTHOR]

Time is the fabric of experience – yet it is incredibly malleable in the mind of the observer: seeming to drag on, or fly right by at different moments. One of the most influential drivers of temporal distortions is attention, where heightened attention dilates subjective time. But an equally important feature of subjective experience involves not just the objects of attention, but also what information will naturally be remembered or forgotten, independent of attention (i.e., intrinsic image memorability). Here we test how memorability influences time perception. Observers viewed scenes in an oddball paradigm, where the last scene could be a forgettable "oddball" amidst memorable ones, or vice versa. Subjective time dilation occurred only for forgettable oddballs, but not memorable ones – demonstrating an oddball effect where the oddball did not differ in low-level visual features, image category, or even subjective memorability. But more importantly, these results emphasize how memory can interact with temporal experience: memorable beginnings may put people in an efficient encoding state, which may in turn influence which moments are dilated in time. [ABSTRACT FROM AUTHOR]

Container-based network emulation offers high fidelity and a scalable testing environment to bridge the gap between research ideas and real-world network applications. However, containers take their notions of time from the physical system clock, and thus the time-stamped events from different containers are multiplexed to reflect the scheduling serialization by the Linux operating system. Conjoining the emulator and other simulators is also challenging due to the difficulties of synchronizing the virtual simulation clock with the physical system clock. Virtual time systems for network emulation shed light on both issues. In this paper, we develop a lightweight container-based virtual time system in Linux Kernel. We use time dilation to trade time with system resources by precisely scaling the time of interactions between containers and physical devices. We develop a time freezer to enable the precise pause and resume of an emulation experiment, which offers the virtual time support to interface with simulators for close synchronization. We integrate the virtual time system into a software-defined networking emulator, Mininet, and evaluate the system accuracy, scalability, and overhead. Finally, we use the virtual-time-enabled emulation testbed to conduct a case study of equal-cost multi-path routing protocol analysis in a data center network. [ABSTRACT FROM AUTHOR]

Special relativity insists that the speed of light in a vacuum is constant for all inertial observers. This is often said to be counterintuitive: why should light alone, among all things in the world, return the same speed value to all inertial observers, regardless of their different states of motion? I argue that this question or puzzle arises because physics misconstrues light by characterizing it as a freestanding phenomenon. As James Gibson insisted, and as any analysis of the visual experience makes plain, light, the agency of sight, cannot be overtaken by sight. A better characterization of light is Gibson's optic array, which prompts the realization that our prior complicity with light keeps us from getting leverage on it as a freestanding phenomenon, and this is why it returns the same speed value to all observers. To show the limitation of freestanding light, I offer two derivations of relativistic time dilation. The first imagines freestanding light and then, to complete the derivation, artificially requires light speed constancy; the second achieves the same result in a fully natural way—that is, without putting observers in an abstract, arguably impossible, situation—by merely attending to the seeing experience. [ABSTRACT FROM PUBLISHER]

Violations of Lorentz invariance in the form of a frame dependence of the speed of light is forbidden by most of modern physics. However, this law is increasingly coming under pressure from theories such as string theory and theories of quantum gravity, which predict violations of Lorentz invariance at some level. This paper presents a concept for a Lorentz invariance test using electromagnetically induced transparency, which, in combination with an effect known as Fresnel drag, can amplify the effect of variations of the speed of light. It is shown how a model apparatus could, in principle, be used to search for frame dependencies in the speed of light to a sensitivity of a part in 10 21 . It is shown that, counter-intuitively, in testing relativistic time dilation, the speed of the particle is not the most important feature and that the test can be performed for relatively small velocities. [ABSTRACT FROM AUTHOR]

ABSTRACT We outline a detailed analysis of a novel scenario, in which gamma-ray bursts are of intergalactic origin and arise from induced collapse of a lone neutron star triggered by a primordial black hole captured ill its center. The energy released from the phase transition of secreted nucleon matter into the quark-gluon plasma is transferred by degenerate neutrinos to the star's surface, where neutrinos annihilate into an electron-positron plasma and produce an inverse temperature layer that preserves a fireball from undue baryonic pollution. Possible observational tests include absence of apparent cosmological time dilation, primary location of γ-ray bursts outside of galaxies, specific shape of logN-logS dependence with a peak at redshift z ∼ 10, emission of 10[sup -4] - 10[sup -3] of total energy in the form of 100 GeV photons, bimodal distribution of durations, very weak accompanying pulse of gravitational radiation, etc. [ABSTRACT FROM AUTHOR]

The greatest philosophical issue facing all sentient beings is one that seeks an answer to the eternal question "What happens to human consciousness at the point of death?" There is considerable anecdotal evidence and numerous conflicting theological and philosophical proposals, but none propose a model based on both known and theoretical science that reflects the anecdotal evidence. The model known as "Cheating the Ferryman" (CTF) attempts to present such a model. This paper gives a detailed analysis of the CTF model with a request for objective peer-analysis of the arguments presented. [ABSTRACT FROM AUTHOR]

This text discusses the groundbreaking contributions of Bud Craig, a neuroscientist, in understanding the pathways and mechanisms of pain and temperature sensations in the brain. Bud's research revealed that the insular cortex is the primary sensory cortex for pain and temperature, resolving a long-standing paradox in the field. His work also highlighted the interoceptive nature of pain and temperature sensations, which are closely related to other bodily sensations such as taste and visceral sensations. Despite facing opposition and criticism, Bud's findings have had a significant impact on the study of interoception and the role of the insula in various conditions. Unfortunately, Bud's illness prevented him from continuing his research, leaving some of his important data unpublished. The author emphasizes the importance of recognizing Bud's contributions and hopes that his work will receive the recognition it deserves. [Extracted from the article]

A major topic that has marked ‘modern physics’ is the theory of special relativity (TSR). The present work focuses on the possibility of teaching the basic ideas of the TSR to students at the upper secondary level in such a way that they are able to understand and learn the ideas. Its aim is to investigate students' learning processes towards the two axioms of the theory (the principle of relativity and the invariance of the speed of light) and their consequences (the relativity of simultaneity, time dilation and length contraction). Based on an analysis of physics college textbooks, on a review of the relevant bibliography and on a pilot study, a teaching and learning sequence consisting of five sessions was developed. To collect the data, experimental interviews (the so-called teaching experiment) were used. The teaching experiment may be viewed as a Piagetian clinical interview that is deliberately employed as a teaching and learning situation. The sample consisted of 40 10th grade students (aged 15–16). The data were collected by taping and transcribing the ‘interviews’, as well as from two open-ended questionnaires filled out by each student, one before and the other after the sessions. Methods of qualitative content analysis were applied. The results show that upper secondary education students are able to cope with the basic ideas of the TSR, but there are some difficulties caused by the following student conceptions: (a) there is an absolute frame of reference, (b) objects have fixed properties and (c) the way events happen is independent of what the observers perceive. [ABSTRACT FROM PUBLISHER]

A dual class of Lorentz transformations (dual LT) for linear and Brownian motions in liquid-like media, is presented and discussed. It descends from two LT groups, for self-diffusion in simple liquids (BLT) and its geometrical analogy (GLT), which turned out to represent promising basic tools to deal with statistics at different length scales. Time dilation and length contraction of BLT occur upon ordering the originally indistinguishable molecular disorder in the liquid medium (i.e., a diffusivity lowering), giving rise to universality and scaling laws in polymer solutions. Dual LT exhibit a rich phenomenology, leading to a scale-dependent motion concept, where Brownian and quantum movements somewhat correspond. Density correlations in simple liquids, for instance, are suggested on this basis to behave like radial wave functions at the atomic scale. We also report some remarks on statistics in general, and its connection towards geometry. [ABSTRACT FROM AUTHOR]

The poesia in ottava rima ('poetry in octave rhyme') is a living tradition of improvised-sung poetry widespread in the rural areas of Central Italy. In this article, I describe and interpret the interaction that takes place between two poet-performers and between poet-performers and the audience, highlighting the importance of embodiment and gesture during the poetic duel and the active role of listeners. This paper aims to highlight the strong binding of speech and gesture and the bodily expressiveness of the onstage improvised sung poetic duel, analysing the contrasto as a 'vocal-gestural performance'. The ultimate aim of this study is to examine the ways in which visual information in the form of gestures contributes to the way musical performance is experienced. Furthermore, we apply insights from ethnomusicology and gesture studies, together with digital video and audio recording and associated analysis software, to the study of contrasto performance. [ABSTRACT FROM AUTHOR]

In this investigation, the head-on collision of dust-acoustic (DA) multi-solitons in a magnetized space dusty plasma consisting of negative dust, Maxwellian electrons and q-nonextensively distributed ions under the influence of polarization force is studied. The presence of the q-nonextensive ions yields eloquent alteration in the polarization force. An increase in the nonextensive parameter (via q) lead to escalate the polarization parameter. Two-sided KdV equations are obtained by adopting Poincaré–Lighthill–Kuo (PLK) method. Further, the direct Hirota method is employed to carry out multi-solitons solutions of KdV equations. The q-nonextensive polarization force has a great impact on the phase shifts after the interaction of single, double, and triple-(DA) solitons. The combined effects of various physical parameters such as polarization force parameter (via R), nonextensivity (via q) and magnetic field strength (via Ω) on the phase shifts of DA multi-solitons have also been illustrated. It is found that the magnetic field alters the polarization effect which leads to modify the phase shifts. The findings of our investigation may be helpful to explore the interaction of multi-solitons in a magnetized space dusty plasma such as planetary rings and comet tails where nonextensively distributed ions, negative dust and Maxwellian electrons are prevalent. [ABSTRACT FROM AUTHOR]

The study is aimed at mathematical modeling of non-stationary temperature and stress-strain fields in growing thermoelastic cylinder, which growth is due to the layer-by-layer sintering over its lateral surface. This modeling makes it possible to estimate the reciprocal impact of non-stationary temperature fields, stress-strain state and the scenario of the additive process even in manufacturing of more complicated shapes. The problem is considered in the framework of the theory of thermal stresses with non-linear radiative boundary condition. A distinctive feature of modeling is that the material composition of the body changes over time. Therefore, the mathematical model is represented by the recurrent sequence of initial boundary value problems, formulated for each step of the additive process in different domains with respect to the increments of thermal and stress fields. The domains constitute nested sequence of regions and, together with the sequence of the moments of layer sintering, define the scenario of additive process. Initial values for a step are taken to be equal to the corresponding values at the final moment of previous step. The solution for each step is represented in the form of decomposition over eigenfunctions of differential operator, generated by boundary value problem on this step. Computational modeling of various sintering modes has been carried out. A classification of thermomechanical additive processes, based on the relationship between the characteristic time of the process and the time of thermal relaxation of the attached layer is given. Special attention is paid to non-uniform volume heating, which can be obtained by skin effect during high-frequency induction. Computational simulations based on obtained analytical solution show that auxiliary inductive heating makes it possible to substantially reduce the non-uniformity of the temperature field and thus to reduce the temperature stresses caused by it. [ABSTRACT FROM AUTHOR]

Modern technology is ubiquitous i.e., "always there" – available to us when we want it and engaging us even when we don't actively seek it. This constantly available ubiquitous technology influences people's perception of time. This conceptual paper explores how ubiquitous technology creates a new time vision we call ubichronic time. We argue ubichronic time is qualitatively different from existing time visions and highlight the new values and behaviours associated with it. Specifically, people who have an ubichronic time vision perform disparate activities that span short durations across the day, find specific tiny units of time valuable and cram many repeated activities into a day. We also argue ubichronic time will have profound implications on the way we work and as such propose new concepts and research directions on how the way we work needs to adapt at the individual, team, and organisational levels. [ABSTRACT FROM AUTHOR]

This article examines three films by Malaysian Dain Said; Bunohan: return to murder (2012), Interchange (2016) and Dukun (2018). Particular attention is paid to the use of land and water (tanah air) imagery, cinematic qualities, and the richness of the cultural practices of Nusantara from which the films arise. Dain's films explore arguments around national identity in the areas of the dramatic and the semantic. Additionally, the cinematic style of these films denotes a struggle between transnational identities and the logics of rigid national cultural boundaries. I argue that the films bring to fore a way of thinking that sees the people of Nusantara living in the interspace and moving smoothly across the archipelago. By perceiving films as 'a liminal site of modern society' and reflecting on 'inbetweenness' as the premise for everything that drives the narratives of Bunohan, Interchange, and Dukun, I maintain that the three films represent a Malaysian interstitial future that emerges between the claims of the past and the demands of the present. These films challenge and explicitly expose the conservative notion of a Malaysian monoculture, and they highlight the complexities of associative relationships through the subjects' fractured sense of belonging. Dain creates images of Nusantara life, characterised by elements of mise en scène with which regional populations can relate. These transnational non-state-centred representations show that the land and the water have defined societies living in the in-between region of Nusantara, and focus on features that reveal the connection between peoples rather than the cultural biases and discrimination that are so often part of national discourses in the region. [ABSTRACT FROM AUTHOR]

The aim of this paper is to explain the significance of Alfred A. Robb's philosophy of time stemming from his interpretation of relativity theory; and at the same time, to investigate the reasons for the failure of his philosophical contemporaries to appreciate its significance, with special attention to its reception on Russell's part. The study of Russell's reaction to Robb exposes shortcomings in Russell's own philosophy of time, which has been extremely influential through the years. It also highlights the philosophical differences between Minkowski and Robb, the shared idealistic premises of Russell and McTaggart, and the confluences between the views of Russell, Eddington and McTaggart. The paper closes with an account of how Robb's interpretation has been vindicated by its adoption in modern physics. [ABSTRACT FROM AUTHOR]

Over the last few years, Italy has occupied a relatively marginal position with respect to the jihadist threat. Nonetheless, the propaganda of the Islamic State mentions Italy and the bordering Vatican with a seemingly disproportionate frequency. This article presents an in-depth analysis of all textual references in Dabiq and Rumiyah, the flagship magazines of this sophisticated jihadist organization. Overall, several mentions concern "Rome," intended as a symbol for the West and Christianity and with a number of other meanings. However, there is no lack of potentially worrying references to Italy, Italians, the Vatican, and the Pope. [ABSTRACT FROM AUTHOR]

Much research has been devoted to the classification of folk songs, revealing that variants are recognised based on salient melodic segments, such as phrases and motifs, while other musical material in a melody might vary considerably. In order to judge similarity of melodies on the level of melodic segments, a successful similarity measure is needed which will allow finding occurrences of melodic segments in folk songs reliably. The present study compares several such similarity measures from different music research domains: correlation distance, city block distance, Euclidean distance, local alignment, wavelet transform and structure induction. We evaluate the measures against annotations of phrase occurrences in a corpus of Dutch folk songs, observing whether the measures detect annotated occurrences at the correct positions. Moreover, we investigate the influence of music representation on the success of the various measures, and analyse the robustness of the most successful measures over subsets of the data. Our results reveal that structure induction is a promising approach, but that local alignment and city block distance perform even better when applied to adjusted music representations. These three methods can be combined to find occurrences with increased precision. [ABSTRACT FROM AUTHOR]

We obtain explicit estimates on the stability of the unique continuation for a linear system of hyperbolic equations. In particular, our result applies to the elasticity system and also the Maxwell system. As an application, we study the kinematic inverse rupture problem of determining the jump in displacement and the friction force at the rupture surface, and we obtain new features on the stable unique continuation up to the rupture surface. [ABSTRACT FROM AUTHOR]

We present Echo+, an expanded and improved version of our previous gameplay tool, Echo. Echo+ is designed to help bridge the gap between video footage analysis and game analytics. It facilitates this by interactively reconstructing gameplay sessions from recorded data, complete with their original graphics. We present and discuss several new features and changes integrated into Echo+, many of which are based on feedback from our previous evaluation of Echo. We also present a user evaluation that compares the usefulness of Echo+ across four different popular game genres. Participants found Echo+ to be useful in all genres, but there was no clear ordering to them regarding usefulness. We identified several key differences in terms of how Echo+ is used in different genres. In addition, we discuss various avenues for expansion of the tool and possible approaches for evaluating it in the future. [ABSTRACT FROM AUTHOR]

The molecular hydrogen ions (MHI) are composed of only two nuclei and a single electron. These simplest molecules are fascinating systems at the interface of atomic and molecular physics. Compared to atoms, they present the additional degrees of freedom of vibration and rotation. The spectrum of rovibrational energies provides an exceptionally large number of transitions that are potentially measurable with extremely small fractional uncertainty. After two decades of theoretical and experimental efforts, precision studies of the vibrational transition frequencies have now reached fractional uncertainties in the low- 10 − 12 range. This is nearing the level of the most accurate experiment-theory comparisons in physics, performed on the hydrogen atom and on the g-factor of the electron. We describe the motivation for the study of MHI, present some relevant theoretical and experimental issues, indicate a few salient results and give an outlook towards future opportunities. [ABSTRACT FROM AUTHOR]

Awe is a complex emotion theorised to impact science learning and practice. In science education, awe has the potential to motivate explanation-seeking, promote conceptual change, and instill feelings of connectedness to the natural world. This exploratory study examined teachers' experiences with awe as well as their uses of awe in their science instruction. Thirty-four elementary (grades 4-5; n =14) and middle school (grades 6-7; n = 20) teachers completed a survey of awe perceptions and experiences and participated in a semi-structured interview. Results showed that science teachers report using awe-invoking classroom experiences in a variety of science disciplines with the intention of leveraging the emotional response in ways that facilitate learning outcomes and inspire long-term science interest. Teachers also reported numerous dispositional factors they perceived as being influential in governing awe experiences in science instruction including age, prior experiences, interest, curiosity, and the presence of co-occurring emotions. This study adds to the developing body of work around awe and science instruction, supports the findings from other fields related to the epistemic and self-transcendent nature of awe, and suggests that awe can be used to enhance science teaching and learning. [ABSTRACT FROM AUTHOR]

This interview with science fiction writer Vandana Singh focuses on her rapidly expanding oeuvre in climate fiction. More specifically, she discusses her cli-fi under the umbrella of three major concerns: their realist settings in a near future, the affirmative depiction of technology as agent, and the representation of climate as a complex system. While the interview focuses largely on Singh's cli-fi forays, it places these recent efforts within her career trajectories as both a noted science fiction writer and a professor of physics at Framingham State University. Besides discussing the politics and aesthetics of her stories that encompasses both humans and nonhumans, the interview also discusses how her pedagogy shapes her imaginative engagements with climate change and the geological epoch of the Anthropocene. [ABSTRACT FROM AUTHOR]

Material culture is an extension of spatial–temporal perceptions and behaviour. The nature of the manner in which rhetorical material is woven into visual narrative become symbolic expressions of material assembly. Mikhail Bakhtin referred to such material assembly as "flesh" in the instance of the novel. In this article, I will extend Bakhtin's notion of "flesh" to film and demonstrate that Edward Hall's theory of mono-chronic and poly-chronic time apply to the materialisation of narrative flesh in the films discussed herein. [ABSTRACT FROM AUTHOR]