Background
Previous studies comparing early laparoscopic cholecystectomy (ELC) with delayed laparoscopic cholecystectomy (DLC) for acute cholecystitis were incomplete. A meta‐analysis was undertaken ...to compare the cost‐effectiveness, quality of life, safety and effectiveness of ELC versus DLC.
Methods
PubMed, Embase, the Cochrane Library and Web of Science were searched for randomized clinical trials (RCTs) that compared ELC (performed within 7 days of symptom onset) with DLC (undertaken at least 1 week after symptoms had subsided) for acute cholecystitis.
Results
Sixteen studies reporting on 15 RCTs comprising 1625 patients were included. Compared with DLC, ELC was associated with lower hospital costs, fewer work days lost (mean difference (MD) –11·07 (95 per cent c.i. –16·21 to −5·94) days; P < 0·001), higher patient satisfaction and quality of life, lower risk of wound infection (relative risk 0·65, 95 per cent c.i. 0·47 to 0·91; P = 0·01) and shorter hospital stay (MD −3·38 (−4·23 to −2·52) days; P < 0·001), but a longer duration of operation (MD 11·12 (4·57 to 17·67) min; P < 0·001). There were no significant differences between the two groups in mortality, bile duct injury, bile leakage, conversion to open cholecystectomy or overall complications.
Conclusion
For patients with acute cholecystitis, ELC appears as safe and effective as DLC. ELC might be associated with lower hospital costs, fewer work days lost, and greater patient satisfaction.
The sooner the better
Alloy design based on single-principal-element systems has approached its limit for performance enhancements. A substantial increase in strength up to gigapascal levels typically causes the premature ...failure of materials with reduced ductility. Here, we report a strategy to break this trade-off by controllably introducing high-density ductile multicomponent intermetallic nanoparticles (MCINPs) in complex alloy systems. Distinct from the intermetallic-induced embrittlement under conventional wisdom, such MCINP-strengthened alloys exhibit superior strengths of 1.5 gigapascals and ductility as high as 50% in tension at ambient temperature. The plastic instability, a major concern for high-strength materials, can be completely eliminated by generating a distinctive multistage work-hardening behavior, resulting from pronounced dislocation activities and deformation-induced microbands. This MCINP strategy offers a paradigm to develop next-generation materials for structural applications.
A high O3 episode with the large increases in surface ozone by 21-42 ppbv and the nocturnal surface O3 levels exceeding 70 ppbv was observed in the region between Xiamen and Quanzhou over the ...southeastern coast of China during 12-14 June 2014, before the Typhoon Hagibis landing. Variations in the surface O3, NO2, CO and meteorology during the Typhoon Hagibis event clearly suggest a substantial impact of the peripheral downdrafts in the large-scale typhoon circulation on such an O3 episode excluding the contributions of photochemical production and the horizontal transport. The influence of vertical O3 transport from the upper troposphere and lower stratosphere (UTLS) region on high surface O3 levels is further confirmed by a negative correlation between surface O3 and CO concentrations as well as dry surface air observed during the O3 episode. This study provides observational evidence of typhoon-driven intrusion of O3 from the UTLS region to surface air, revealing a significant effect of such a process of stratosphere-troposphere exchange (STE) of O3 on tropospheric O3 and ambient air quality.
The impact of central Asian aridification on the low latitude North Pacific Ocean since the late Miocene remains unclear. To address this question, we systematically studied an abyssal manganese ...nodule from the northwestern Pacific Ocean, which is expected to be sensitive to eolian dust sourced from central Asia. Geochemical variations and the fossilized remains of magnetotactic bacteria within the studied nodule manifest two prominent Asian aridification events at ∼8–7 Ma and 3.6–0 Ma. These results suggest that central Asian aridification impacted both primary productivity and abyssal microbial activity in the NW Pacific Ocean via eolian dust inputs. In contrast to the Pliocene aridification event, the late Miocene event was associated with a primary productivity bloom that is not evident in coeval global primary productivity records, which indicates that the ∼8–7 Asian aridification event was likely due to NE Tibetan Plateau uplift rather than to global cooling.
Plain Language Summary
Central Asian aridification since the late Miocene has had a significant influence on climate, temperature, and North Pacific Ocean productivity through eolian dust inputs transported by westerlies. However, it is unclear whether the low latitude of NW Pacific Ocean responded to this aridification. We systematically analyzed the geochemistry and magnetism of a NW Pacific manganese nodule, and find that Asian aridification since, the late Miocene impacted biogeochemical cycling and abyssal microbial activity in the NW Pacific Ocean via eolian dust input. Our results imply that these two prominent Asian aridification events at around 8–7 Ma and ca. 3.6 Ma can be attributed to the NE Tibetan Plateau uplift and global cooling, respectively.
Key Points
A manganese nodule from the NW Pacific carries a paleoclimatic record of Asian aridification since the Late Miocene
Asian aridification impacted biogeochemical cycling and abyssal microbial activity in the NW Pacific Ocean
Major Asian aridification events at ∼8–7 Ma and ∼3.6–0 Ma may be attributed to NE Tibetan Plateau uplift and global cooling, respectively
Abyssal manganese nodules have been explored widely for their economic potential and paleoenvironmental significance. Debate about whether biogenic or physical‐chemical processes are responsible for ...their formation remains because of difficulties in quantifying ancient microbiological contributions. To address this question, we investigated microbial fossils in manganese nodules from the western Pacific Ocean by integrating scanning electron microscope, transmission electron microscope, and synchrotron transmission X‐ray microscope observations. Our results suggest that the nodules host abundant fossil biogenic magnetite and manganese‐oxidizing bacteria. These organisms engage in redox reactions or live in environments with redox gradients. By combining magnetic properties and observations of fossil biogenic magnetite morphology, we estimate magnetofossil abundances and further assess fossil biogenic manganese oxide in nodules. Our results imply that manganese nodule formation appears to be dominated by biomineralization with an additional terrestrial contribution. Extensive biomineralization in ultralow‐productivity oceanic environments suggests that manganese nodule formation is an important aspect of biogeochemical cycling in abyssal seafloor environments.
Key Points
Abyssal ferromanganese nodules host abundant fossil biogenic magnetite and manganese oxide produced in environments with redox gradients
Redox reactions fueled abyssal microbial activity and contributed to biomass production in microecosystems within nodules
Manganese nodule formation appears to be dominated by biomineralization
Background
Pomegranate peels have been widely used to treat diarrhea in China. The antidiarrheal activities of aqueous extracts of pomegranate peels have been evaluated. However, there have not been ...any bioactivity‐guided fractionation studies on the antidiarrheal effect to identify the bioactive components of the extract.
Methods
Bioactivity‐guided fractionation of an aqueous extract of pomegranate peels was performed using different solvents of increasing polarity, generating fractions dissolved in ethyl acetate, n‐butyl alcohol, and the residual fraction. The principal chemical composition of the active fraction was analyzed by HPLC/ESI‐MS.
Key Results
Fecal frequencies revealed that only the ethyl acetate fraction possessed significant antidiarrheal activity. Furthermore, administration of the ethyl acetate fraction at 100, 200, and 400 mg/kg significantly reduced gastrointestinal transit in charcoal meal tests in mice. It also significantly inhibited castor oil‐induced enteropooling compared to control animals. Histopathological analysis revealed that small intestine lesions of mice treated with the ethyl acetate fraction were alleviated compared to those in mice treated with castor oil. The ethyl acetate fraction was found to be composed mainly of punicalagin, corilagin, and ellagic acid, and a combination of these compounds could mediate the antidiarrheal activities.
Conclusion and Inferences
Our study describes the protective effects of pomegranate peels against castor oil‐induced diarrhea. The findings showed that the ethyl acetate fraction was the active fraction of pomegranate peels, of which punicalagin, corilagin, and ellagic acid were responsible for the antidiarrheal effect of aqueous extracts.
The antidiarrheal activities of aqueous extracts of pomegranate peels have been evaluated. However, the effective ingredients of antidiarrheal activities need to be determined.( The ethyl acetate fraction was the active fraction of pomegranate peels, of which punicalagin, corilagin, and ellagic acid were responsible for the antidiarrheal effect of aqueous extracts. )Determination of effective ingredients is conductive to the application of pomegranate peels on diarrheal diseases.
About 3196 EA-type binaries (EAs) were observed by LAMOST by 2017 June 16 and their spectral types were derived. Meanwhile, the stellar atmospheric parameters of 2020 EAs were determined. In this ...paper, those EAs are cataloged and their physical properties and evolutionary states are investigated. The period distribution of EAs suggests that the period limit of tidal locking for the close binaries is about 6 days. It is found that the metallicity of EAs is higher than that of EW-type binaries (EWs), indicating that EAs are generally younger than EWs and they are the progenitors of EWs. The metallicities of long-period EWs ( days) are the same as those of EAs with the same periods, while their values of Log (g) are usually smaller than those of EAs. These support the evolutionary process that EAs evolve into long-period EWs through the combination of angular momentum loss (AML) via magnetic braking and case A mass transfer. For short-period EWs, their metallicities are lower than those of EAs, while their gravitational accelerations are higher. These reveal that they may be formed from cool short-period EAs through AML via magnetic braking with little mass transfer. For some EWs with high metallicities, they may be contaminated by material from the evolution of unseen neutron stars and black holes or they have third bodies that may help them to form rapidly through a short timescale of pre-contact evolution. The present investigation suggests that the modern EW populations may have formed through a combination of these mechanisms.
A low-temperature solar Rankine system utilizing R245fa as the working fluid is proposed and an experimental system is designed, constructed and tested. Both the evacuated solar collectors and the ...flat plate solar collectors are used in the experimental system, meanwhile, a rolling-piston R245fa expander is also mounted in the system. The new designed R245fa expander works stably in the experiment, with an average expansion power output of 1.73
kW and an average isentropic efficiency of 45.2%. The overall power generation efficiency estimated is 4.2%, when the evacuated solar collector is utilized in the system, and with the condition of flat plate solar collector, it is about 3.2%. The experimental results show that using R245fa as working fluid in the low-temperature solar power Rankine cycle system is feasible and the performance is acceptable.
Neoadjuvant therapy is recommended for locally advanced esophageal cancer, but the optimal strategy remains unclear. We aimed to evaluate the safety and efficacy of neoadjuvant chemoradiotherapy ...(nCRT) versus neoadjuvant chemotherapy (nCT) followed by minimally invasive esophagectomy (MIE) for locally advanced esophageal squamous cell carcinoma (ESCC).
Eligible patients staged as cT3-4aN0-1M0 ESCC were randomly assigned (1 : 1) to the nCRT or nCT group stratified by age, cN stage, and centers. The chemotherapy, based on paclitaxel and cisplatin, was administered to both groups, while concurrent radiotherapy was added for the nCRT group; then MIE was carried out. The primary endpoint was 3-year overall survival. This study is registered with ClinicalTrials.gov (NCT03001596).
A total of 264 patients were eligible for the intention-to-treat analysis. By 30 November 2021, 121 deaths had occurred. The median follow-up was 43.9 months (interquartile range 36.6-49.3 months). The overall survival in the intention-to-treat population was comparable between the nCRT and nCT strategies hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.58-1.18; P = 0.28, with a 3-year survival rate of 64.1% (95% CI 56.4% to 72.9%) versus 54.9% (95% CI 47.0% to 64.2%), respectively. There were also no differences in progression-free survival (HR 0.83, 95% CI 0.59-1.16; P = 0.27) and recurrence-free survival (HR 1.07, 95% CI 0.71-1.60; P = 0.75), although the pathological complete response in the nCRT group (31/112, 27.7%) was significantly higher than that in the nCT group (3/104, 2.9%; P < 0.001). Besides, a trend of lower risk of recurrence was observed in the nCRT group (P = 0.063), while the recurrence pattern was similar (P = 0.802).
NCRT followed by MIE was not associated with significantly better overall survival than nCT among patients with cT3-4aN0-1M0 ESCC. The results underscore the pending issue of the best strategy of neoadjuvant therapy for locally advanced bulky ESCC.
•The CMISG1701 trial assessed the safety and efficacy of nCRT versus nCT followed by MIE for locally advanced bulky ESCC.•The nCRT followed by MIE strategy could not improve survival significantly compared with the nCT strategy.•The best strategy of neoadjuvant therapy for locally advanced bulky ESCC remains a pending issue.
This paper presents the analysis of low-temperature solar Rankine cycles for power generation using zeotropic mixtures. Three typical mass fractions 0.9/0.1 (Ma) 0.65/0.35 (Mb), 0.45/0.55 (Mc) of ...R245fa/R152a are chosen. In the proposed temperature range from 25
°C to 85
°C, the three zeotropic mixtures are investigated as the working fluids of the low-temperature solar Rankine cycle. Because there is an obvious temperature glide during phase change for zeotropic mixtures, an internal heat exchanger (IHE) is introduced to the Rankine cycle. Investigation shows that different from the pure fluids, among the proposed zeotropic mixtures, the isentropic working fluid Mb possesses the lowest Rankine cycle efficiency. For zeotropic mixtures a significant increase of thermal efficiencies can be gained when superheating is combined with IHE. It is also indicated that utilizing zeotropic mixtures can extend the range of choosing working fluids for low-temperature solar Rankine cycles.