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Greg Marchand,1 Kelly Ware,1,2 Malini Govindan,1 Ahmed T Masoud,1,3 Alexa King,1,2 Stacy Ruther,1 Giovanna Brazil,1 Kaitlynne Cieminski,1 Nicolas Calteux,1 Catherine Coriell,1 Hollie Ulibarri,1 Julia Parise,1 Amanda Arroyo,1 Diana Chen,4 Maria Pierson,4 Rasa Rafie,5 Katelyn Sainz1 1Marchand Institute for Minimally Invasive Surgery, Mesa, AZ, USA; 2International University of Health Sciences, Basseterre, St. Kitts; 3Fayoum University Faculty of Medicine, Fayoum, Egypt; 4Midwestern University College of Osteopathic Medicine, Glendale, AZ, USA; 5Rocky Vista University College of Osteopathic Medicine, Parker, CO, USACorrespondence: Greg MarchandMarchand Institute for Minimally Invasive Surgery, 10238 E. Hampton, Ste. 212, Mesa, AZ, 85209, USATel +1 4809990905Fax +1 4809990801Email gm@marchandinstitute.orgObjective: We set out to evaluate whether the instillation of bupivacaine versus a saline solution into the peritoneal cavity at time of laparoscopic gynecologic surgery will reduce postoperative pain and postoperative opioid consumption.Data Sources: We searched six databases: Web of Science, SCOPUS, Cochrane CENTRAL, ClinicalTrials.Gov, MEDLINE and PubMed. Our search strategy had no restriction on time or languages and included all studies that met our search algorithm up to March of 2021.Methods of Study Selection: We included only randomized trials that met our search strategy for the outcomes of 1) pain intensity 24 hours after surgery, 2) pain intensity 6 hours after surgery, and 3) length of hospital stay.Tabulation, Integration, and Results: We analyzed continuous data using mean difference (MD) with relative 95% confidence interval (CI). We included 8 randomized clinical trials. We found that intraperitoneal bupivacaine showed significant difference from the saline group regarding pain intensity 24 hours after surgery (MD= − 0.73 [− 1.10, − 0.36]) (P = 0.01) and pain intensity 6 hours after surgery (MD= − 1.12 [− 2.22, − 0.02]) (P = 0.05). Overall, patients allocated to the placebo group seemed to need other analgesics earlier than patients allocated to the bupivacaine group (MD=145.08 [51.37, 238.79] (P = 0.02)). There was no significant difference regarding the length of hospital stay (MD= − 0.44 [− 1.44, 0.56]) (P = 0.39).Conclusion: Bupivacaine significantly reduced the visual analog pain score for pain compared with that of the placebo at 6 and 24 hours postoperatively. There was no significant difference in hospital stay.Prospero Registration: CRD42021254268.Keywords: ERAS, marcaine, bupivacaine, enhanced recovery after surgery, intra-abdominal anesthetic

X-ray diffraction measurements of liquid water are reported at pressures up to 360 MPa corresponding to a density of 0.0373 molecules per Å3. The measurements were conducted at a spatial resolution corresponding to Qmax = 16 Å-1. The method of data analysis and measurement in this study follows the earlier benchmark results reported for water under ambient conditions having a density of 0.0333 molecules per Å3 and Qmax = 20 Å-1 [J. Chem. Phys. 138, 074506 (2013)] and at 70°C having a density of 0.0327 molecules per Å3 and Qmax = 20 Å-1 [J. Chem. Phys. 141, 214507 (2014)]. The structure of water is very different at these three different T and P state points and thus they provide the basis for evaluating the fidelity of molecular simulation. Measurements show that at 360 MPa, the 4 waters residing in the region between 2.3 and 3 Å are nearly unchanged: the peak position, shape, and coordination number are nearly identical to their values under ambient conditions. However, in the region above 3 Å, large structural changes occur with the collapse of the well-defined 2nd shell and shifting of higher shells to shorter distances. The measured structure is compared to simulated structure using intermolecular potentials described by both first-principles methods (revPBE-D3) and classical potentials (TIP4P/2005, MB-pol, and mW). The DFT-based, revPBE-D3, method and the many-body empirical potential model, MB-pol, provide the best overall representation of the ambient, high-temperature, and high-pressure data. The revPBE-D3, MB-pol, and the TIP4P/2005 models capture the densification mechanism, whereby the non-bonded 5th nearest neighbor molecule, which partially encroaches the 1st shell at ambient pressure, is pushed further into the local tetrahedral arrangement at higher pressures by the more distant molecules filling the void space in the network between the 1st and 2nd shells. [ABSTRACT FROM AUTHOR]

First order phase transition occurs in cristobalite at a pressure of 1.2 gigapascals. The transition is reversible with hysteresis, when the pressure is reduced. Monoclinic and triclinic symmetry characterizes the high-pressure phase in cristobalite. Pure and Ca/Al-stabilized SiO2 cristobalite is compressed by the rotation of rigid SiO4 tetrahedra at a pressure of 0.6 gigapascals and a temperature of 298 kelvin. There is no distortion in the geometry of the cristobalite.

Here we present diffraction data that yield the oxygen-oxygen pair distribution function, gOO(r) over the range 254.2-365.9 K. The running O-O coordination number, which represents the integral of the pair distribution function as a function of radial distance, is found to exhibit an isosbestic point at 3.30(5) Â. The probability of finding an oxygen atom surrounding another oxygen at this distance is therefore shown to be independent of temperature and corresponds to an O-O coordination number of 4.3(2). Moreover, the experimental data also show a continuous transition associated with the second peak position in gOO(r) concomitant with the compressibility minimum at 319 K. [ABSTRACT FROM AUTHOR]

We present the in situ neutron diffraction data of a water and silica mixture at high pressure and temperature. We show initially the formation of ice VI at 1.5 GPa at 290 K in the presence of crystalline SiO2, upon heating we observe its melting at ∼400 K. Upon further warming to 1200 K, we observe melting of the crystalline silica. Upon cooling to 290 K and recovery to ambient pressure, we obtain a mixture of silica in the coesite structure and liquid water. These results have implications for the phase diagram of the coesite–water solidus and hence the behaviour of fluids at mantle conditions. [ABSTRACT FROM AUTHOR]

Presents a study that investigated the phase stability and atomic-level compression mechanisms for both silicon oxide cristobalite and for cristobalite partially stabilized by calcium/aluminum doping. Details of the experiment; Results and discussion; Conclusion.

Presents the results of single-crystal electron microprobe analysis of a lanthanum (La) lutetium (Lu) gallium (Ga) garnet (G). Importance of compound in laser-diode-pumped solid-state laser materials; Use of electron microprobe; Information on the atomic coordinates and thermal parameters of LaLuGaG.

High energy X-ray diffraction has been combined with containerless techniques to determine the structure of a series of alkali and ammonium nitrate and nitrite liquids. The systems have been modelled using molecular dynamics simulation which allows for the flexibility of, and movement of charge within, the molecular anions. The model reproduces the experimentally-determined scattering functions in both the low- and high-Q regimes reflecting the inter- and intra-molecular length-scales. For ammonium nitrate the best fit to the diffraction data is obtained by assuming the NH4+ cation to have a radius closer to that for Cs+ rather than a smaller cation such as Rb+ as often previously assumed. The alkali nitrites show an emergent length scale, attributed to the nitrogen–nitrogen spatial correlations, that depends on both temperature and the identity of the alkali cation. The corresponding nitrates show a more subtle effect in the nitrogen–nitrogen correlations. As a result, the nature of this N–N length-scale appears different for the respective nitrites and nitrates. [ABSTRACT FROM AUTHOR]

Although many studies have been performed, no consensus exists as to the ideal entry for laparoscopic gynecologic surgery. We sought out to compare the safety of direct trocar insertion with that of the Veress needle entry technique in gynecologic laparoscopic surgery. This is the largest analysis to date on this subject. Meta-Analysis. Gynecologic laparoscopic surgery. Randomized clinical trials comparing methods of laparoscopic initial entry. Inclusion criteria included women undergoing gynecological laparoscopic surgery, with the intervention of the direct trocar insertion technique compared with Veress needle entry technique. The pooled analysis showed that Veress needle entry was associated with a significant increase in the incidences of extraperitoneal insufflation (RR=0.177, 95% Cl[0.094, 0.333], p<0.001), omental injury (RR=0.418, 95% Cl[0.195, 0.896], p<0.001), failed entry (RR=0.173, 95% Cl [0.102, 0.292], p<0.001), and trocar site infection (RR=0.404, 95% Cl[0.180, 0.909], p<0.029). There was no significant difference between the two groups regarding the visceral injury (RR=0.562, 95% Cl[0.047, 6.676], p<0.648). When excluding all data apart from gynecologic surgery, the Veress needle entry technique may have an increased incidence of some, but not all complications of laparoscopic entry. It may also have a higher incidence of failed entry compared to direct entry techniques. Care should be taken in extrapolating these general results to specific surgeon experience levels. [ABSTRACT FROM AUTHOR]

Although laparoscopic radical hysterectomy (LRH) and robotic radical hysterectomy (RRH) are both minimally invasive procedures commonly performed for the treatment of early-stage cervical cancer, there is little high quality data on the head-to-head comparison of these two procedures. We sought to perform the largest study to date to compare the efficacy and complications of these two procedures. Systematic Review and Meta-Analysis. Gynecologic Oncology. Women suffering from early-stage cervical cancer. We included retrospective cohorts, prospective cohorts, case-control, and randomized clinical trials. Laparoscopic radical hysterectomy compared with Robotic radical hysterectomy. We found that following RRH, women had a decreased hospital stay (MD=0.80[0.38,1.21], (P<0.002). We found no differences in estimated blood loss (MD=35.24[-0.40,70.89],(P=.05), blood transfusion rate ((OR=1.32[0.86,2.02],(P=0.20), rate of post-operative complications (OR=0.84[0.60,1.17],(P=0.30), the operative time (MD=6.01[-4.64,16.66],(P=0.27), number of resected lymph node (MD=-1.22[-3.28,0.84],(P=0.25) intraoperative complications (OR=0.78[0.51,1.19],(P=0.25), five-year overall survival (OR=1.37[0.51,3.69],(P=0.53), lifetime disease free survival (OR=0.89[0.59,1.32],(P=0.55), intraoperative and postoperative mortality (within 30 days) (OR=1.30[0.66,2.54],(P=0.44), and recurrence (OR=1.14[0.79,1.64],(P = 0.50). RRH seems to result in the patient leaving the hospital sooner after surgery. We were unable to find any differences in our ten other outcomes related to complications or efficacy. [ABSTRACT FROM AUTHOR]

Magnesium hydroxyfluoride, Mg(OH)F, has been synthesized by a subcritical hydrothermal route from a 1:1 molar mixture of brucite, Mg(OH)2, and sellaite, MgF2 with a rutile type structure, in excess water. Using a combination of synchrotron X-ray and time-of-flight neutron powder diffraction, the structure of Mg(OH)F has been solved in the diaspore space group Pnma with a = 10.116(3), b = 4.6888(10) and c = 3.0794(7) Å at ambient conditions. The most intense diffraction lines are [dobs (hkl) Iobs]: 2.291 (211) 10, 4.253 (101) 7, 1.747 (212) 7, 2.229 (401) 6 and 1.480 (610) (4) Å, with the largest d-spacing at 5.058 Å. Sharp infrared stretching bands are located at 3679 and 3645 cm-1, with a broader band at 3535 cm-1. The topology of the structure is intermediate between that of the OH and F endmembers, being derived through notional shearing nearly normal to the sheets of octahedra of the CdI2/Mg(OH)2-type structure. Further similar shearing at an interval ½a would lead to a Cd(OH)F-type structure, which is also related to the rutile structure type. The observations and model presented here indicate a close correlation between the structural properties of the endmembers and Mg(OH)F. [ABSTRACT FROM AUTHOR]

The high-pressure behavior of nanocrystalline mackinawite (FeS) with particle sizes of 6, 7 and 8 nm has been investigated by high-energy X-ray total scattering and pair distribution function analysis. An irreversible first-order structural phase transition from tetragonal mackinawite to orthorhombic FeS-II was observed at about 3 GPa. The transition is induced by the closure of the van der Waals gap in the layered mackinawite structure. A grain size effect on the transition pressure and the compressibility was observed. [ABSTRACT FROM AUTHOR]

This paper presents a contribution to understanding the behavior of solar-powered air conditioning and refrigeration systems with a view to determining the manner in which refrigeration rate, mass flows, heat transfer areas, and internal architecture are related. A cogeneration system consisting of a solar concentrator, a cavity-type receiver, a gas burner, and a thermal storage reservoir is devised to simultaneously produce heat (hot water) and cooling (absorption refrigerator system). A simplified mathematical model, which combines fundamental and empirical correlations, and principles of classical thermodynamics, mass and heat transfer, is developed. The proposed model is then utilized to simulate numerically the system transient and steady-state response under different operating and design conditions. A system global optimization for maximum performance (or minimum exergy destruction) in the search for minimum pull-down and pull-up times, and maximum system second law efficiency is performed with low computational time. Appropriate dimensionless groups are identified and the results are presented in normalized charts for general application. The numerical results show that the three-way maximized system second law efficiency, ηII,max,max,max, occurs when three system characteristic mass flow rates are optimally selected in general terms as dimensionless heat capacity rates, i.e. (ψss, ψwxwx, ψHs)opt=(0.335, 0.28, 0.2). The minimum pull-down and pull-up times, and maximum second law efficiencies found with respect to the optimized operating parameters are sharp and, therefore, important to be considered in actual design. As a result, the model is expected to be a useful tool for simulation, design, and optimization of solar energy systems in the context of distributed power generation. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The crystal structure of deuterated topaz [topaz-OD; Al2SiO4(OD)2], synthesized at 10 GPa and 800 °C, has been determined using neutron powder diffraction at pressures up to 7.5 GPa. The linear axial compressibilities obtained from regressions of the lattice constants vs. pressure are βa = 1.87(1) x 10-3 GPa-1, βb = 1.71(1) x 10-3 GPa-1, and βc = 2.73(1) x 10-3 GPa-1. The occupancy of the D1 site was found to be greater than that of D2, as shown independently using neutron diffraction and infrared spectra at ambient conditions. A bifurcated hydrogen bond involving the D1 site, O4-D1···O2 and O4-D1···O3, and a trifurcated hydrogen bond involving D2 site, O4-D2···O1, O4-D2···O2, and O4-D2···O4 are proposed for hydrogen-bond donor and acceptor pairs in addition to those reported previously. The observed pressure dependences of the hydrogen-bonding geometry show that these donor and acceptor pairs are classifiable into two types of interaction: (1) those that strengthen as a function of pressure (O4-D1···O3, O4-D2···O2, and O4-D2···O4) and (2) those that weaken (O4-D1···O1 and O4-D2···O1). These results also demonstrate that the reason for the contrasting behavior of the ν(OH) between F-rich natural topaz and topaz-OH are both the cooperative effect, O4-D2···O4-D1···O3, and the increasing Al-O4 distance. [ABSTRACT FROM AUTHOR]

OH stretching vibration modes for F-rich natural topaz (F-topaz) and for fully hydrated topaz (topaz-OH) synthesized at high pressure, were observed using IR and Raman spectroscopies at pressures up to 30.4 GPa and 17.3 GPa, respectively. In F-topaz, the pressure derivative of the frequency of the OH stretching band observed at 3650 cm-1 at ambient pressure was 0.91(3) cm-1/GPa, which was consistent with the value recently reported by Bradbury and Williams (2003). On the other hand, in topaz-OH, the pressure derivatives of the bands initially at 3599 and 3522 cm-1 were-5.2(2) and -2.56(6) cm-1/GPa, respectively. This contrasting behavior between the two forms of topaz at high pressures suggests that the OH substitution for F in topaz affects the hydrogen-bonding behavior under high pressure. [ABSTRACT FROM AUTHOR]

Presents information about a simulation of an ethanol?water distillation column assisted by a vapor-compression heat pump. Development of a simulation model to study working fluids R-11 and R-114; Findings that considerable reduction in energy consumption can be achieved with the installation of a heat pump.

Neutron powder diffraction data of phase A (Mg7Si2O8(OH)6) were collected at ambient pressure and 3.2 GPa (calculated from the compressibility of phase A) from the deuterated compound, and the structure was refined using the Rietveld method. The derived crystal structure implies that hydrogen atoms occupy two distinct sites in phase A, both forming hydrogen bonds of different lengths with the same oxygen atom. This picture is supported by IR spectra, which exhibit two absorption bands at 3400 and 3513 cm−1 corresponding to OH stretching vibrations, and proton NMR spectra, which display two peaks with equal intensities and isotropic chemical shifts of 3.7 and 5 ppm. The D-D distance [D(1)-D(2) distance] at ambient pressure was found to be 2.09 ± 0.02 Å from the neutron diffraction data and 2.09 ± 0.05 Å from the NMR spectra. At 3.2 GPa, there is no statistically significant increase in the O-D interatomic distance while the hydrogen bonding interaction D···O appears to increase for one of the hydrogen sites, D(1), which has the stronger hydrogen bonding interaction compared with the other hydrogen, D(2), at ambient pressure. The O-D bond valences, determined indirectly from the D···O distances were 0.86 and 0.91 at ambient pressure, and 0.83 and 0.90 at 3.2 GPa, for D(1) and D(2), respectively. [ABSTRACT FROM AUTHOR]

The present work introduces a transient endoreversible model of a heat-driven refrigeration plant, which is driven by a fuel-burning heater. The model consists of a combustion chamber with negligible heat loss to the ambient, a refrigerator with three finite-size heat exchangers, namely, the evaporator between the refrigeration load and refrigerant, the condenser between the refrigerant and the ambient, and the generator between the combustion chamber and the refrigerant, and finally the refrigerated space. The total thermal conductance of the three heat exchangers is fixed. A thermodynamic optimization of the absorption cycle is then performed, reporting the operating conditions for minimum time to reach a prescribed cold-space temperature, thus maximum refrigeration rate, specifically, the optimal mass fuel flow rate and the optimal way of allocating the thermal conductance inventory. Half of the total supply of thermal conductance has to be divided equally between the generator and evaporator and the other half allocated to the condenser, for optimal operation. A narrow range of fuel flow rates lead to the minimum time to achieve a prescribed cold-space temperature, thus stressing the importance of the transient analysis. Appropriate dimensionless groups were identified and the generalized results are reported in dimensionless charts. [ABSTRACT FROM AUTHOR]

We aimed to conduct this systematic review and meta-analysis to investigate and compare the efficacy of laparoscopic and TAC in patients with CI. Systematic Review with Meta-analsysis. We searched PubMed, Scopus, MEDLINE, ClinicalTrials.Gov, Cochrane and Web of Science using suitable keywords. Retrieved citations were screened for our criteria. We extracted all outcomes reported then analyzed using Open Meta-Analyst and Review Manager Software. We included all study designs (observational and randomized controlled trials) that included patients with CI that underwent laparoscopic cerclage or TAC. We excluded non-English trials and full-text not available. N/A. We included a total of 43 studies. Laparoscopic and TAC had a positive effect by increasing gestational age; for laparoscopic (MD = 14.86 weeks (W), 95% CI [10.67, 19.05], P < 0.001) and TAC (MD = 12.79 W, 95% CI [10.97, 14.61], P < 0.001). Also, laparoscopic had a positive effect regarding neonatal survival (RR = 0.981, 95% CI [0.95, 1.012], P < 0.001) and TAC (RR = 0.23, 95% CI [0.18, 0.31], P < 0.00001). Furthermore, all outcomes assessed (total fetal survival rate, baby weight, operative time, hospital stay, gestational age > 34, < 34 and < 24 weeks) were significant except preterm delivery; laparoscopic (RR = 0.116, 95% CI [-0.006, 0.238], P = 0.063) and TAC (MD = 1, 95% CI [0.45, 2.24], P = 1), and Gestational age < 34 weeks for laparoscopic group (RR = 0.446, 95% CI [-0.323, 1.215], P = 0.256). In patients with CI, both TAC and laparoscopic cerclage procedures revealed a positive effect in preserving the pregnancy. In contrast to previous reviews including fewer studies, our meta-analysis did not show a statistically significant difference in survival in the laparoscopic over trans-abdominal cerclage groups. [ABSTRACT FROM AUTHOR]

Explains the use of the pressure generated in a multi-anvil apparatus to affect changes in crystal structure, elastic properties and the stress state in ceramics. Crystallographic studies; Discussions on the strength and rheological properties of ceramic materials; Simultaneous measurements of ultrasonic and X-ray diffraction.