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Objective The primary purpose of this study was to examine any potential difference in clinical outcomes between transcarotid artery revascularization performed under local anesthesia compared with general anesthesia by utilizing a large national database. Methods The primary outcome of the study was a composite endpoint of postoperative in-hospital stroke, myocardial infarction and mortality following transcarotid artery revascularization for the index procedure. Secondary outcomes included a composite outcome of postoperative in-hospital stroke, transient ischemic attack, myocardial infarction and mortality along with several subsets of its components and each individual component, flow reversal time (min), radiation dose (GY/cm2), contrast volume utilized (mL), total procedure time (min), extended total length of stay (>1 day) and extended postoperative length of stay (>1 day). Statistical analyses employed both descriptive measures to characterize the study population and analytic measures such as multivariable mixed-effect linear and logistic regressions using both unmatched and propensity-score matched cohorts. Results A total of 2609 patients undergoing transcarotid artery revascularization between the years 2016 and 2018 in the US were identified, with 82.3% performed under general anesthesia and 17.7% under local anesthesia. The primary composite outcome was observed in 2.3% of general anesthesia patients versus 2.6% of local anesthesia patients ( p = 0.808). The rate of postoperative transient ischemic attack and/or myocardial infarction was 1.6% with general anesthesia versus 1.1% with local anesthesia ( p = 0.511). For adjusted regression analysis, general anesthesia and local anesthesia were comparable in terms of primary outcome (OR: 0.72; 95% CI: 0.27–1.93, p = 0.515). As for the secondary outcomes, no significant differences were found except for contrast, where the results demonstrated significantly less need for contrast with procedures performed under general anesthesia (coefficient: 4.94; 95% CI: 1.34–8.54, p = 0.007). A trend towards significance was observed for lower rate of postoperative transient ischemic attack and/or myocardial infarction (OR: 0.33; 95% CI: 0.09–1.18, p = 0.088) and lower flow reversal time under local anesthesia (coefficient: –0.94: 95% CI: –2.1–0.22, p = 0.111). Conclusions Excellent outcomes from transcarotid artery revascularization for carotid stenosis were observed in the VQI database between the years 2016 and 2018, under both local anesthesia and general anesthesia. The data demonstrate the choice of anesthesia for transcarotid artery revascularization does not appear to have any effect on clinical outcomes. Surgical teams should perform transcarotid artery revascularization under the anesthesia type they are most comfortable with.

A quantitative survey of local television news directors in the United States ( N = 159) explored three main topics: the perception/attitudes of current local TV news directors, potential differences in those attitudes by market size, and whether news directors felt “in step” with their staff and/or upper management. The results indicated that the majority of news directors are still White, male, and middle-aged. News directors see a strong connection between news product quality and resources devoted to news. News directors were also, overall, pessimistic about the future of the TV news industry. Analysis indicated that there were few differences among the news directors working in large, medium, and small markets. Further, news directors reported being somewhat “out-of-step” with their staff and management regarding profit and market orientation.

The possibility of assessing the average crystallite size of cellulose in wood by formalised modelling from the magnitude of the potential difference arising in the wood specimen owing to polarisation in a non-homogeneous temperature field is considered.

Icy roads in wintertime present a hazard for road users. It is therefore desirable to maintain bare roads. To achieve this, deicing chemicals are typically applied. One important property of the chemicals that are used is how fast they can melt ice. Understanding what affects the melting rate, however, is limited. An experiment was therefore designed to study how the driving force for the melting—the chemical potential difference between ice and solution—affects the chemical melting rate of ice. In this study, the driving force was represented by the solution freezing points. The experiment was performed at −5°C (23°F) by using the solutions of four chemicals: sodium chloride, magnesium chloride, and calcium chloride, as well as potassium formate. These four solutions were mixed to have four freezing points. They were −10°C (14°F), −18°C (−0.4°F), −30°C (−22°F); and the eutectic temperature of each chemical. The results showed that there was a clear correlation between solution freezing point and how fast the solution could melt ice. The solutions with the lowest freezing point melted ice four to five times faster than the solutions with the highest freezing point. The importance of solution freezing point was attributed to its direct relation to the solution chemical potential, with a low freezing point giving a large driving force for the phase change. In addition, it was found that the type of chemical plays a role on the melting rate of ice. The fastest melting chemical (potassium formate) melted ice 45% faster than the slowest melting chemical (magnesium chloride), which is attributed to potassium formate having a higher ion mobility. A higher ion mobility allows a faster transport of solute to the ice–solution interface.

Unearthed relics and earthen sites are historical evidence of our cultural heritage. Many of them are referred to as immobile cultural relics since both the relics-in-itself and their surroundings are our historic heritage of past emperor’s burial with significant historical importance such that they cannot be moved into indoor-display museums. Researchers have studied the specific environmental specifications to establish the desired steady temperature, humidity and air quality for collections and visitors in indoor-display museums. However, due to the unique exhibition characteristics, the conservation of earthen sites is still a challenge to environmental scientists and technologists, and how to effectively protect these ancient sites has been a major concern globally. Archaeology museum is developing advanced techniques to prevent weathering of relics caused by the sun, wind and rain. The in-situ relics in archaeology museum are far from being well preserved because of the lack of understanding of site conservation and the impact of indoor micro-climatic conditions. Many of them are suffering deteriorations or even ruins due to improper preservation environment adopted for maintenance of relics. Among the hazards that unearthed relics are facing with, desiccation cracking is the most common and problematic. The drying layer of the earthen site in the Banpo museum (Xi’an, China) is thicker than 0.4m (see Figure 1(a)). The same phenomena are also found in the Emperor Qin’s Terra-Cotta Warriors and Horses Museum (see Figure 1(b)), the water content of the earthen site decreased from 15% to 22% in 1994 when it was excavated to less than 5% now, such that serous shrinkage and cracking occurred on the surface of the site. To upgrade the conservation of the relics in archaeology museums, great efforts have been made in recent years, e.g. maintenance of a high relative humidity (RH) and space division in the exhibiting hall have been implemented in archaeology museum as a part of the preservation regime. The underground exhibiting hall of Hanyangling Museum (Xi’an, China) is such a modern archaeology museum (see Figure 1(c)). It exhibits partially exposed pits containing pottery figurines in the co-burial grave of the fourth Emperor (188–141 B.C.) and Queen of Han Dynasty, China. The enclosed space for relics’ domain is being maintained at about 24 C in summer and 16 C in the winter. Moreover, the RH has been maintained at a level higher than 95% to prevent the drying of unearthed relics and sites. However, the water content of the earthen site in the exhibiting hall still decreased from over 15% when it was excavated in 2006 to around 4% in 2009. In addition to the desiccation cracking, gypsum was found to deposit on the surface of relics due to the transport mechanism by which the carbonates were diffused and migrated with moisture across the air-relic-topsoil complex interfaces. The carbonates would react with the penetrating SO2 from the ambient atmosphere to form sulphates (see Figure 1(d)). The reason why desiccation cracking occurs in high humidity environment is not entirely clear. The conservation protocol, i.e. space division and maintaining a high RH as a preservation regime, has been considered by archaeologists as an approved practice and therefore the protocol was applied to new archaeology museums; however, cracking still persists in the terracotta relics and earthen sites. The desiccation cracking of unearthed relics and excavated sites in these archaeology museums seems to be a spontaneous process even though the RH of the atmospheric environment was at approximately the ceiling value (100%). In order to clarify the mechanism of moisture migration behind the desiccation cracking phenomenon and to verify whether a high RH is adequate to prevent the desiccation cracking of unearthed in-situ relics, the chemical potential analysis

The author discusses the results of Business Information Review’s 25th Business Information Survey, commenting from a US perspective. Trends in providing value-added deliverables, working with data, working with vendors, open access and open-source resources, technology, mobile access, skills, and hiring are highlighted. The article concludes that trends in business information services in the US and UK are closely aligned and that we must continue to look for opportunities to add value to business information services. The US/UK use of non-English language sources, acting on the big data opportunity, the importance of information technology enablers, and user-centric design appear as areas of potential difference.

This article tests for the existence of two types of selection biases in sports markets. First, the better-educated players and players of higher socioeconomic background have better outside opportunities. If they decide to follow a professional soccer career, they must be truly good to compensate their higher opportunity costs. Second, if innate athletic talent is distributed equally among the population, we should not find any difference in the performance evaluation of White and non-White players. This potential difference provides a ‘‘market test’’ for discrimination. Using data on the Uruguayan Soccer League in the 2000 and 2001 seasons, we find evidence of these two types of selection biases. Our estimations show a positive relationship between education and performance, education and promotions, socioeconomic background and performance, socioeconomic background and promotions, and discrimination against non-White players in the national league but not with respect to international soccer markets.

Natural feline coronavirus (FCoV) infection has been shown to not only induce intestinal infection with viral shedding, but also systemic infection which either remains without clinical signs or leads to feline infectious peritonitis (FIP). As systemic infection is not the key event in the development of FIP, the question arises as to whether a potential difference in viral load might be of importance. Therefore, the purpose of this study was to quantitatively assess feline coronavirus (FCoV) RNA loads in haemolymphatic tissues of healthy, long-term FCoV-infected cats and cats with FIP. In cats that died from FIP, viral loads were significantly higher, indicating a higher rate of viral replication or a reduced capacity for viral clearance in cats developing and/or suffering from FIP.

Aim/Background We previously reported that esophageal epithelium (EE), both stratified squamous (SS) and Barrett9s (BE), from pinch biopsies could be mounted and studied electrically in mini-Ussing chambers and showed that they have distinctly different electrical parameters, including significantly different short-circuit currents (Isc). Methods To further elucidate the nature of the differences in Isc in these two types of EE, jumbo biopsies were obtained from subjects with normal SS or subjects with BE and mounted in mini-Ussing chambers (Lucite rings of aperture diameter 2 mm) for measurement of potential difference, Isc and calculation of total electrical resistance while bathed in normal Ringer9s solution at 37°C, pH 7.4, gassed with 95%O2/5%CO2. Following basal recordings of Isc, tissues were exposed to either Cl-free Ringer9s or HCO3-free HEPES Ringer bubbled with O2. To validate that the tissues under study were viable and that the Isc was not the result of severe edge damage, only tissues in which serosal ouabain, 1 mM, reduced Isc by ≥ 89% at the end of the experiments were used. Results (Means ± SEM). For ESSE (n = 18) vs BSCE (n = 6): basal PD was -1.2 ± 0.2 vs -3.6 ± 2 mV; Isc was 4.2 ± 0.9 vs 42 ± 19 μAmps/cm2 and RT was 360 ± 42 vs 68 ± 10 ohm.cm2. Notably basal Isc and RT were significantly different for SS vs BE (p Conclusions Human SS epithelium and BE have markedly different capacities for active ion transport, BE exhibiting a ten-fold greater current. The higher current in BE is generated by active Cl secretion (˜ 38% of Isc) and active HCO3 secretion (˜ 16% of Isc). The active HCO3 secretion is notable for its ability to contribute to protection of BE against acid injury as part of the pre-epithelial buffer zone.

Cheek pouches were removed from anesthetized hamsters and were either tape-stripped or left intact and then mounted in Ussing chambers, where they were bathed in Krebs-Ringer bicarbonate saline. A potential difference could be measured across all pouches and was stable for over an hour across the unstripped pouches. The electrical resistance across the unstripped pouches was high (8960 Ω.cm2), whereas the resistance across the tape-stripped pouches was significantly lower (p Reflection coefficients of urea, ethanol, and glycerol were derived by means of streaming potentials. Values for intact pouches were all close to 1 and for tape-stripped pouches were 0.938, 0.822, and 0.509, respectively. Permeability coefficients for urea and ethanol across intact and tape-stripped pouches were, respectively, 12.5 × 10-9 cm/min; 27.6 x 10-9 cm/min; 2325 × 10 -9 cmlmin ; and 28471 × 10-9 cmlmin. The hamster cheek pouch has a high electrical resistance; it is an impermeable structure in which the keratin layer appears to provide a major barrier to the passage of water, ions, and certain solutes.

The potential protective properties of esaprazole on the gastric mucosa following administration of aspirin were evaluated by measurement of the potential difference across the gastric mucosa. Twelve patients with non-ulcer dyspepsia were admitted to the study and were divided into two groups of six patients each. In association with a randomized double-blind scheme the two groups of patients underwent two tests, with placebo and esaprazole 600 or 900 mg. After 30 min of basal recording of the potential difference, patients received either esaprazole or placebo i.v. and recording was continued for a further 30 min. Afterwards, 600 mg of unbuffered aspirin was instilled into the stomach through a nasogastric tube and the potential difference was measured for 60 min. Esaprazole 600 mg did not prevent the fall in the potential difference across the gastric mucosa caused by aspirin. A higher dose of esaprazole, however, did significantly (p≤0.05) reduce the fall. These results suggest that esaprazole exerts a dose-dependent cytoprotective effect on the gastric mucosa in man.

The effect of severe anoxia produced by gassing with 100% nitrogen on gastric mucosal permeability and hydrogen ion back diffusion was investigated using an in vitro preparation of rabbit fundic gastric mucosa mounted in an Ussing chamber. Permeability was estimated by determination of the flux of the water soluble, nonlipidsoluble molecule erythritol from the mucosal to serosal solution. The flux rate across normal tissue was 2.80 plus or minus 0.41 pmoles/cm-2/sec, and rose to 3.32 plus or minus 0.57 pmoles/cm-2/sec after 2 hr of severe anoxia. Hydrogen ion ack diffusion was measured by determining with a pH stat the amount of hydrogen required to maintain the [H+] of the mucosal solution at 0.1, 1.0, 2.0 and 3.2 mEq/L in both normal and anoxic tissues. One hour of anoxia increased the back diffusion of H+, but the changes only became statistically significant at all pH values after 1.5 hr. Anoxia did however cause an immediate fall in potential difference to zero, and a rise in resistance which after 30 min fell progressively to preanoxic levels. Anoxia produces a small increase in gastric mucosal, permeability, an effect which may be enhanced by other factors.

As far as we have been able to discover, there have been no published investigations of action potentials in heart muscle cultures. This is a report on a method which it is hoped will furnish information on the mechanism of irritable tissues in general and particularly those which are excited spontaneously.In general, the potential difference between the micro-electrodes making contact with a muscle culture is impressed on the grid of a vacuum tube and measured by the deflection of a string galvanometer in the plate circuit.The cultures were prepared by the usual hanging drop technique. Small pieces of the ventricle of 16-day rat embryos were explanted in a medium of rat blood plasma and rat embryo extract. The ages of the cultures varied from 2 days to 2 months. The present records were taken from the older cultures containing outgrowths of muscle which had differentiated in the manner described by Goss1 and were presumably without nervous tissue elements. Spontaneous contraction occurs in practically al...

Recently Burr and associates1 discovered that ovulation in the rabbit is accompanied by large increases in electrical potential. Observations on women, using the apparatus and technique described by Burr, Lane, and Nims,2 have been reported by Burr and Musselman.3 Applications of the vacuum tube potentiometer have been reported also by Reboul, Friedgood, and Davis,4 and by Rock, Reboul, and Wiggers.5 The present preliminary report offers the results of an attempt to apply the Burr-Lane-Nims technique to the study of ovulation in the chimpanzee.A sexually mature chimpanzee (No. 4 in the laboratory series), with regular menstrual cycles, was trained to present the backs of her hands for the application of salt-bridge electrodes and to remain passive during the course of a series of potential difference measurements. Measurements were taken daily over a period of several weeks.The curve of Fig. 1 shows the potential measurements in millivolts through a normal sexual cycle (April 6 to May 6). Each voltage poi...

Summary1. The potential difference across the wall of the middle section of the small intestine was determined with rats, golden hamsters, and guinea pigs in vitro. The value obtained when normal R...

ConclusionsThe experiments discussed here indicate that a potential difference, requiring the expenditure of metabolic energy, is maintained across the chorioallantoic membrane, the inner surface being negative. Its value is somewhat smaller than the potential observed across most other biologically active membranes (1), and it is unlikely that these small electric forces would act directly as organizing agents in a tissue graft on the membrane. Nevertheless the potential difference may be an expression of an underlying metabolic asymmetry, maintained for example by a gradient of CO2 or O2 across the membrane, which could be related more relevantly to the observed polar reconstitution of the organs in the experiments of Weiss and Taylor.

Falk1 showed that the electrophoretic mobility velocity (potential difference) of diphtheria bacilli varied according to their virulence, the more virulent organisms showing low mobility rate, while those of a less virulent nature gave a higher reading. For pneumococcus,2 on the contrary, he found that the potential difference is higher the greater the virulence for white mice and vice versa. The sequence of decreasing potentials was shown to be Types III, I, II, IV, which follows the decreasing virulence for white mice. This work on the pneumococcus was carried out prior to the isolation of several new types from the erstwhile group IV.Following the technique of Petroff3 the writers undertook the dissociation of a stock strain of avian tubercle bacillus procured originally from Dr. Krumwiede of the Research Laboratories, New York City Department of Health. When the culture was planted on Proskauer and Beck medium after a suitable period of incubation at 37° C. the organism had dissociated into rough and ...

ConclusionsIt has been shown that the important characteristic amplitude properties of the alpha component of the normal human EEG, in the usual monopolar and bipolar derivations primarily depend on the attenuating properties of the tissue through which the potential difference is transmitted. Moreover, noting the correspondence between waveforms seen in the normal EEG and those produced by an artificial occipital electric dipole in the cadaver, it is clear that the spread of an occipital electric disturbance is an excellent model for the production of the amplitude characteristics of the basic alpha component of the normal EEG.

It has been shown1 that when a cell of Nitella is cut a wave of some sort, which we may for convenience call a death wave, passes rapidly along the cell and that at each spot it reaches a characteristic death process is brought about. In dilute solutions (e. g. 0.001 M KCl) this consists of a sudden change whereby the protoplasm becomes more negative after which its potential difference approaches zero.These alterations are irreversible but similar changes of a reversible character may occur spontaneously or may be induced by a variety of reagents (both organic, and inorganic). After the removal of the reagents the changes often cease at once or after some minutes. Very often these changes are rhythmical and appear to travel along the cell, sometimes at a high rate of speed.During the past 5 years a large number of such cases have been recorded photographically by means of the technique previously described.2 These are being studied with a view to correlating all the phenomena since, to arrive at a theory...

Earlier papers1 have described the reversal of the normally positive potential difference across the protoplasm of impaled cells of Halicystis osterhoutii (Bermuda) both by exposure to ammonia (or other weak bases) and by perfusion of the vacuole with more alkaline sap or sea water. The author was then inclined to explain the former effect by the latter, since penetration of ammonia raised the vacuolar pH. One difficulty of this interpretation was that the Californian species, H. ovalis, did not show such reversal on perfusion with sea water at pH 8.0 or higher, although reversing well on exposure to ammonia. This difference between the species now seems reconciled by referring the effects in both cases to the penetration of ammonia into the protoplasm. This is shown in H. ovalis by introducing into the perfusing fluid a trace of NH4Cl; at pH 5.0, the normal acidity of the sap, no effect is observed, but if sea water now is perfused at pH 8.0, reversal of potential often results. Then as perfusion is cont...

It has long been known that virulent strains of pneumococci or other bacteria are not readily ingested by leucocytes and that avirulent strains are generally ingested readily. It has also been established that the presence of acids, alkalies, salts and other reagents modify the velocity or the extensiveness of phagocytic reactions.In studies on the parallel relations between virulence, electro-phoretic potential difference (P. D.), agglutinability and other characteristics of bacteria, strains of pneumococci of different virulence for white mice were examined in considerable detail.1 The pneumococci designated A are virulent Type I organisms. The strains B and C are variants of A which were derived by Blake and Trask by growing strain A in the presence of specific anti-serum. The minimum fatal doses for white mice are: 0.5 × 10-7 cc. for A; 0.5 × 10-3 cc. for B; and 0.5+ cc. for C. The P. D. is highest on A and lowest on C.The experiments reported here were undertaken to determine the extent to which A, B...

The typical curve which has been secured for growth of organisms in varying hydrogen ion concentrations is platycurtic and bimodal. Jacques Loeb1 secured similar curves for the viscosity, osmotic pressure, potential difference, and swellability of gelatin and other proteins. He explained the bimodality of these graphs upon the basis of the Donnan's equilibrium, and arrived at the conclusion that the median minimum lying between the acid and the alkaline optima respectively is located at the isoelectric point of the protein in each case. In physico-chemical investigations, then, one seems quite warranted in regarding the median minimum of curves plotted along the pH scale as a sound criterion of the isoelectric point of the protein involved. A number of biologists, including Robbins2 and Pearsall,3 have undertaken to utilize this relationship in the interpretation of similar graphs obtained in the study of plants and animals, that is, concluding, for instance, that the median minimum for growth curves is a...

It has been found possible to emulsify a highly cohesive and agglutinable strain with M/50 sodium oleate, which concentration was less than for any other of a number of salts used, which included M/16 MgCl, M/8 Na Citrate, M/2 NaCl, copper acetate and CaCl2, which are given in the order of their emulsifying efficiency.With threshold concentrations of certain of the emulsifying salts the organism spreads suddenly over the surface of the liquid. The phenomenon is well recognized to be one of surface tension depression.It is probable that the emulsifying action of the oleate is brought about by its ability to diminish the abruptness at the interfacial boundary between the bacterium and the solution. This view accords with the fact that COONa radical of the oleate is truly soluble in the water, and the hydrocarbon radical is not. The obvious lipoidal nature of the wall of the bacterium in question makes probable the adsorption of the oleate anion; in fact, repeated washing restores the flocculability. These c...