Single-incision laparoscopic appendectomy vs conventional laparoscopic appendectomy:Systematic review and meta-analysis

AIM: To assess the differences in clinical benefits and disadvantages of single-incision laparoscopic appendectomy(SILA) and conventional laparoscopic appendectomy(CLA).METHODS: The Cochrane Library,MEDLINE,Embase,Science Citation Index Expanded,and Chinese Biomedical Literature Database were electronically searched up through January 2013 to identify randomized controlled trails(RCTs) comparing SILA with CLA.Data was extracted from eligible studies to evaluate the pooled outcome effects for the total of 1068 patients.The meta-analysis was performed using Review Manager 5.2.0.For dichotomous data and continuous data,the risk ratio(RR) and the mean difference(MD) were calculated,respectively,with 95%CI for both.For continuous outcomes with different measurement scales in different RCTs,the standardized mean difference(SMD) was calculated with 95%CI.Sensitivity and subgroup analyses were performed when necessary.RESULTS: Six RCTs were identified that compared SILA(n = 535) with CLA(n = 533).Five RCTs had a high risk of bias and one RCT had a low risk of bias.SILA was associated with longer operative time(MD = 5.68,95%CI: 3.91-7.46,P < 0.00001),higher conversion rate(RR = 5.14,95%CI: 1.25-21.10,P = 0.03) and better cosmetic satisfaction score(MD = 0.52,95%CI: 0.30-0.73,P < 0.00001) compared with CLA.No significant differences were found for total complications(RR = 1.15,95%CI: 0.76-1.75,P = 0.51),drain insertion(RR = 0.72,95%CI: 0.41-1.25,P = 0.24),or length of hospital stay(SMD = 0.04,95%CI:-0.08-0.16,P = 0.57).Because there was not enough data among the analyzed RCTs,postoperative pain was not calculated.CONCLUSION: The benefit of SILA is cosmetic satisfaction,while the disadvantages of SILA are longer operative time and higher conversion rate.

Association of three single nucleotide polymorphisms of ESR1 with breast cancer susceptibility:a meta-analysis

Expression of estrogen receptors is correlated with breast cancer risk,but inconsistent results have been reported.To clarify potential estrogen receptor（ESR）-related breast cancer risk,we analyzed genetic variants of ESR1 in association with breast cancer susceptibility.We performed a meta-analysis to investigate the association between rs2234693,rs1801132,and rs2046210（single nucleotide polymorphisms of ESR1）,and breast cancer risk.Our analysis included 44 case-control studies.For rs2234693,the CC genotype had a higher risk of breast cancer compared to the TT or CT genotype.For rs2046210,the AA,GA,or GA ＋ GG genotype had a much higher risk compared to the GG genotype.No significant association was found for the rs 1801132 polymorphism with breast cancer risk.This meta-analysis demonstrates association between the rs2234693 and rs2046210 polymorphisms of ESR1 and breast cancer risk.The correlation strength between rs2234693 and breast cancer susceptibility differs in subgroup assessment by ethnicity.

Non-platinum doublets versus single agents in non-small cell lung cancer （NSCLC） patients with elderly age and/or poor performance status： a meta-analysis

Objective： The aim of the study was to compare the efficacies and toxicities of non-platinum doublets （doublets group） with a non-platinum single agent （single-agent group） in previously untreated advanced non-small cell lung cancer （NSCLC） patients with elderly age and/or poor performance status （PS）. Methods： The PubMed database was screened. Subsequently, the hazard ratios （HRs） for overall survival （OS） and progression-free survival （PFS）, relative risks （RRs） for overall response rate （ORR） and one-year survival, and odds ratios （ORs） for the different types of toxicities were pooled using the Review Manager 5.0 package. Results： This study comprised of 1427 patients enrolled in four randomized controlled trials. The pooled HR showed that the doublet group could increase ORR （P = 0.002） with no heterogeneity （P = 0.64）, and might improve OS （P = 0.01 / P = 0.06） with heterogeneity （P 0.001）. There was no significant difference in PFS （P = 0.16） and one-year survival （P = 0.25） between two treatment groups. The doublet group led to more grade 3/4 neutropenia and thrombocytopenia than the single-agent group （P = 0.02 and P = 0.000, respectively）. The incidences of grade 3/4 anemia, vomiting, mucositis, constipation, diarrhea, neurotoxicity, allergy, and fatigue between the two treatment groups were insignificant. Conclusion： Except for neutropenia and thrombocytopenia, the non-platinum doublets could increase ORR, and might improve OS for NSCLC patients with elderly age and/or poor PS without addition of more side effects; however, the doublets showed an increased rate of neutropenia and thrombocytopenia. The addition of doublets may not improve PFS and one-year survival.

Dynamic strength of rock with single planar joint under various loading rates at various angles of loads applied

Intact rock-like specimens and specimens that include a single, smooth planar joint at various angles are prepared for split Hopkinson pressure bar（SHPB） testing. A buffer pad between the striker bar and the incident bar of an SHPB apparatus is used to absorb some of the shock energy. This can generate loading rates of 20.2-4627.3 GPa/s, enabling dynamic peak stresses/strengths and associated failure patterns of the specimens to be investigated. The effects of the loading rate and angle of load applied on the dynamic peak stresses/strengths of the specimens are examined. Relevant experimental results demonstrate that the failure pattern of each specimen can be classified as four types： Type A, integrated with or without tiny flake-off; Type B, slide failure; Type C, fracture failure; and Type D, crushing failure. The dynamic peak stresses/strengths of the specimens that have similar failure patterns increase linearly with the loading rate, yielding high correlations that are evident on semi-logarithmic plots. The slope of the failure envelope is the smallest for slide failure, followed by crushing failure, and that of fracture failure is the largest. The magnitude of the plot slope of the dynamic peak stress against the loading rate for the specimens that are still integrated after testing is between that of slide failure and crushing failure. The angle of application has a limited effect on the dynamic peak stresses/strengths of the specimens regardless of the failure pattern, but it affects the bounds of the loading rates that yield each failure pattern, and thus influences the dynamic responses of the single jointed specimen. Slide failure occurs at the lowest loading rate of any failure, but can only occur in single jointed specimen that allows sliding.Crushing failure is typically associated with the largest loading rate, and fracture failure may occur when the loading rate is between the boundaries for slide failure and crushing failure.

Effect of solidification rate on MC-type carbide morphology in single crystal Ni-base superalloy AM3

In order to study the effect of the withdrawing rate on carbide morphology,MC-type carbide in single crystal superalloy AM3 was systematically investigated with sample growth rates from 3.5 μm/s to 500 μm/s.The carbide morphologies were investigated by scanning electron microscopy(SEM),and the electron probe microanalysis(EPMA) was used to characterize the carbide composition.The results indicate that the solidification rate is the important factor governing MC carbide growth morphology,size and distribution,composition and growth mechanism.With the increase of withdrawing rate,nodular,rod-like,Chinese script types of carbide morphology are observed.For the low withdrawing rate,with the increase of withdrawing rate,the carbide size becomes larger.For the case of dendritic interface,the carbide size becomes smaller with refinement of dendrites as withdrawing rate increases.The volume fraction of carbides increases with the withdrawing rate increasing.

SOLIDIFICATION AND MICROSEGREGATION BEHAVIORS OF NICKEL-BASE SINGLE CRYSTAL SUPERALLOY SOLIDIFIED AT MEDIUM COOLING RATE

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Evolution mechanism of recrystallization in a nickel-based single crystal superalloy under various cooling rates during heat treatment

The recrystallization behaviors of a nickel-based single crystal superalloy during heat treatment at 1,200℃ for 4 h with various cooling rates were studied.Results show that the thickness of recrystallization layer decreases with the increase of cooling rate.In addition,the microstructures ofγ′phase in the recrystallization region are different in various cooling rates.In the high cooling rates(70,100℃·min^(-1)),small size and high volume fraction ofγ′phases are formed in the recrystallization region.It is also found that irregular fine secondaryγ′phases are precipitated between matrix channels with an average size of 150 nm in the original matric(100℃·min^(-1)).The sizes of the secondaryγ′phase decrease with the increase of cooling rate.In contrast,large size and small volume fraction ofγ′phases are formed in the recrystallization region,and a grain boundary layer is formed under a low cooling rate(10℃·min^(-1)).The evolution mechanism of recrystallization at various cooling rates during heat treatment is analyzed.

Grain Yield and Nitrogen Use Efficiency Vary with Cereal Crop Type and Nitrogen Fertilizer Rate in Ethiopia: A Meta-Analysis

The crop production in Ethiopia is markedly constrained by soil nutrient depletion and limited fertilizer input. Nitrogen is among the most yield-limiting factors of cereal crops, especially in sub-Saharan Africa (SSA). A meta-analysis of 82 studies was carried out to evaluate the response of major cereal crops, viz. wheat, maize, barley, teff, and sorghum, to nitrogen fertilization in Ethiopia. The results showed that N-application significantly increased yields of all the five crops examined herein. The average yields of the treatment effects over controls for the five crops were 3775.8 kg∙ha−1 and 2593.3 kg∙ha−1, respectively. The overall yield response to nitrogen treatments for all the crops was 64.8% (wheat, 96.5%;maize, 40.65%;barley 84.36%;teff, 50.48%;and sorghum;23%). Overall, nitrogen agronomic efficiency (AEN) and partial factor productivity (PFPN) were 18.2 and 71.81 kg∙kg−1, respectively. A downtrend of nitrogen use efficiency with an increase in N rate was realized. The yield response was higher for the nitrogen treatment effects of >100 kg∙N∙ha−1 (123.9%), clay soils (75.46%), low initial soil organic carbon (SOC) and available phosphorous (AP) (92.4% and 101.6%), respectively, Therefore, we recommend the application of nitrogen fertilizer (>100 kg∙N∙ha−1), especially on infertile soils for improved grain yield and NUE in aforementioned cereal crops in Ethiopia and similar regions in sub-Saharan Africa (SSA).

Dark count rate and band to band tunneling optimization for single photon avalanche diode topologies

This paper proposes two optimal designs of single photon avalanche diodes(SPADs) minimizing dark count rate(DCR). The first structure is introduced as p^+/pwell/nwell, in which a specific shallow pwell layer is added between p^+and nwell layers to decrease the electric field below a certain threshold. The simulation results show on average 19.7%and 8.5% reduction of p^+/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. Moreover, a new structure is introduced as n+/nwell/pwell, in which a specific shallow nwell layer is added between n+and pwell layers to lower the electric field below a certain threshold. The simulation results show on average 29.2% and 5.5% decrement of p^+/nwell structure’s DCR comparing with similar previous structures in different operational excess bias and temperatures respectively. It is shown that in higher excess biases(about 6 volts), the n+/nwell/pwell structure is proper to be integrated as digital silicon photomultiplier(dSiPM) due to low DCR. On the other hand, the p^+/pwell/nwell structure is appropriate to be utilized in dSiPM in high temperatures(above 50?C) due to lower DCR value.

STRAIN RATE SENSITIVTTY OF POLYCRYSTALLINE AND SINGLE CRYSTAL NiAl

The compressive and tensile strain rate sensitivities of polycrystalline and single crystal NiAl have been evaluated at 877 ℃ which is well above DBTT. Samples were prepared to specific sizes by hot press consolidation of appropriate powder sizes and minimizing past consolidation thermal exposures. NiAl single crystals were grown in the [100]orientation using a modified Bridgeman technique. The yield and tensile strength of polycrystalline NiAl as a function of grain size generally follows a Hall-Petch type relationship . A tensile strain rate effect was found at strain rate of 1 to 10-4 sec-1. The strain rate sensitivity coefficient, m,in the equation of σ = Kε is in the range of 0. 10 to 0. 13. The highest strain rate (1 sec-1) resulted in significantly higher strengths and little or no observed ductility. Compressive strain rate testing al strain rate of 10-5to 10-2 sec-1 and at temperature of 1050°to 1250°K was conducted both for polycrystalline and for single crystal NiAl. The calculated stress exponents and the activation energy for creep were compared with the reference data.

Network meta-analysis of the prognosis of curative treatment strategies for recurrent hepatocellular carcinoma after hepatectomy

BACKGROUND Recurrent hepatocellular carcinoma(rHCC)is a common outcome after curative treatment.Retreatment for rHCC is recommended,but no guidelines exist.AIM To compare curative treatments such as repeated hepatectomy(RH),radiofrequency ablation(RFA),transarterial chemoembolization(TACE)and liver transplantation(LT)for patients with rHCC after primary hepatectomy by conducting a network meta-analysis(NMA).METHODS From 2011 to 2021,30 articles involving patients with rHCC after primary liver resection were retrieved for this NMA.The Q test was used to assess heterogeneity among studies,and Egger’s test was used to assess publication bias.The efficacy of rHCC treatment was assessed using disease-free survival(DFS)and overall survival(OS).RESULTS From 30 articles,a total of 17,11,8,and 12 arms of RH,RFA,TACE,and LT subgroups were collected for analysis.Forest plot analysis revealed that the LT subgroup had a better cumulative DFS and 1-year OS than the RH subgroup,with an odds ratio(OR)of 0.96(95%CI:0.31-2.96).However,the RH subgroup had a better 3-year and 5-year OS compared to the LT,RFA,and TACE subgroups.Hierarchic step diagram of different subgroups measured by the Wald test yielded the same results as the forest plot analysis.LT had a better 1-year OS(OR:1.04,95%CI:0.34-03.20),and LT was inferior to RH in 3-year OS(OR:10.61,95%CI:0.21-1.73)and 5-year OS(OR:0.95,95%CI:0.39-2.34).According to the predictive P score evaluation,the LT subgroup had a better DFS,and RH had the best OS.However,meta-regression analysis revealed that LT had a better DFS(P<0.001)as well as 3-year OS(P=0.881)and 5-year OS(P=0.188).The differences in superiority between DFS and OS were due to the different testing methods used.CONCLUSION According to this NMA,RH and LT had better DFS and OS for rHCC than RFA and TACE.However,treatment strategies should be determined by the recurrent tumor characteristics,the patient’s general health status,and the care program at each institution.

Clinical effect of preventive nursing on the rate of deep vein thrombosis in patients with lung cancer: A meta-analysis

Objective:To explore the clinical effect of preventive nursing intervention on deep venous thrombosis rate,nursing satisfaction and average hospitalization time after treatment of lung cancer.Methods:Chinese databases(Wanfang,Weipu and China Knowledge Network)and English databases(Pubmed,Cochrane and Scopus)were searched and read references for relevant research.Statistical analysis was performed using Review Manager 5.3.The odds ratio(OR)and the mean difference(MD)were used as the combined effect values of the comparison groups.Sensitivity analysis was performed by changing the effect model or excluding the literature with a large weight ratio,and the symmetry of the funnel plot was observed for publication bias test.Results:A total of 14 Chinese studies included.Compared with routine nursing intervention,preventive nursing intervention could significantly reduce the rate of deep vein thrombosis after lung cancer treatment[OR=0.16(0.10,0.23)],improve nursing satisfaction[OR=6.42(3.32,12.41)]and shorten the average hospital stay[MD=-7.41(-8.16,-6.65)],without heterogeneous existing.And regardless of whether the lung cancer patient was undergoing resection or chemotherapy,the effect of preventive nursing intervention to reduce the rate of deep vein thrombosis was very significant.Conclusion:Preventive nursing intervention is beneficial to patients with lung cancer,which can significantly reduce the formation rate of deep vein thrombosis,which is worthy of clinical promotion.

<i>Lactobacillus</i>GG Supplementation on Anti-<i>Helicobacter pylori</i>Therapy-Related Side Effects and Eradication Rates: A Meta-Analysis

Background: Concerns still exist with respect to unsatisfactory eradication rates and/or therapy-associated side effects for the use of standard triple therapy in the treatment of Helicobacter pylori infection, which prompts considerable interest in new therapy. We systematically reviewed the literature to investigate whether Lactobacillus GG as supplementation to standard triple therapy could improve H. pylori eradication rates and/or reduce therapy-associated side effects. Methods: PubMed, EMBASE, the Cochrane Central Register of Controlled Trials (CENTRAL) were systematically searched from their inception to August 4, 2015 for randomized controlled trials (RCTs). The language was restricted to English only. Results: Four RCTs involving a total of 305 participants (including 83 children) were included. Lactobacillus GG given along with triple therapy significantly reduced the risk of overall H. pylori therapy-related adverse effects (three RCTs, n = 221, RR 0.59, 95% CI 0.45 - 0.78), particularly of diarrhea (four RCTs, n = 285, RR 0.23, 95% CI 0.11 - 0.47), bloating (four RCTs, n = 289, RR 0.61, 95% CI 0.41 - 0.90), and taste disturbance (four RCTs, n = 288, RR 0.38, 95% CI 0.23 - 0.62). There were no significant differences between groups in the risk of other adverse effects. No beneficial effects of Lactobacillus GG were observed for H. pylori eradication rates (four RCTs, n = 284, RR 0.99, 95% CI 0.88 - 1.13). Conclusion: Current evidence indicates that Lactobacillus GG administered along with standard triple therapy is a feasible way to reduce therapy-related side effects, particularly diarrhea, bloating, and taste disturbance. However, Lactobacillus GG shows no effects on eradication rates.

Theoretic expression of flow rate for a single fracture with linearly varying width

By means of reasonable assumption and mathematical derivation, a theoretic expression of flow rate for a single fracture with linearly varying width was obtained. The mathematical derivation was based on the cubic law and the new theoretic expression was an extention of traditional parallel plate model. This study may help to analyze seepage in fractured rock mass.

Meta-analysis of the willingness rate of community home-based care in China

Objective:To systematically evaluate the willingness rate of the community to provide for the aged at home and analyze its influencing factors.Methods:By searching the CNKI,VIP,Wanfang,we collected literature on the willingness of the elderly in the community to provide for the aged from 2011 to 2021,extracted the data,and evaluated the quality of the included literature.Then,CMA 2.0 software was used for Meta-analysis.Results:A total of 13 articles were included in this study,and 16,402 people over 60 years old were surveyed,1782 people were willing to provide for the aged at home in the community,with a total willingness rate of 11%(95%CI:9%to 26%).The results of subgroup analysis showed that there was a statistically significant difference in the community home care willingness rate of elderly people with different gender,education levels,marital status,monthly income,living alone,the number of children,and residence(P<0.05).There was not any statistically significant difference in the willingness rate of the elderly with different ages,chronic diseases,self-care ability,and loneliness(P>0.05).Conclusion:The overall willingness rate of the elderly in the community of the elderly is relatively low in China.Gender,education level,marital status,monthly income,living alone,number of children,and residence are factors affecting the prediction of community elderly will.

Single-Channel Speech Enhancement Using Critical-Band Rate Scale Based Improved Multi-Band Spectral Subtraction

This paper addresses the problem of single-channel speech enhancement in the adverse environment. The critical-band rate scale based on improved multi-band spectral subtraction is investigated in this study for enhancement of single-channel speech. In this work, the whole speech spectrum is divided into different non-uniformly spaced frequency bands in accordance with the critical-band rate scale of the psycho-acoustic model and the spectral over-subtraction is carried-out separately in each band. In addition, for the estimation of the noise from each band, the adaptive noise estimation approach is used and does not require explicit speech silence detection. The noise is estimated and updated by adaptively smoothing the noisy signal power in each band. The smoothing parameter is controlled by a-posteriori signal-to-noise ratio (SNR). For the performance analysis of the proposed algorithm, the objective measures, such as, SNR, segmental SNR, and perceptual evaluations of the speech quality are conducted for the variety of noises at different levels of SNRs. The speech spectrogram and objective evaluations of the proposed algorithm are compared with other standard speech enhancement algorithms and proved that the musical structure of the remnant noise and background noise is better suppressed by the proposed algorithm.

Effect of ruthenium on γ' precipitation behavior and evolution in single crystal superalloys

The effect of Ru on γ＇ precipitation behavior and evolution in single crystal superalloys with different Ru contents were investigated by scanning electron microscopy with energy dispersive spectroscopy,3D atomic probing,differential scanning calorimetry.The results show that the solvus of the γ＇ phase decreases gradually with increasing Ru content in the alloys by casting or by the same solution and aging treatments,the alloy with a larger Ru content yields a smaller γ＇ phase.The addition of Ru increases the growth rate and coarsening rate of the γ＇ phase.Ru mainly distributes in the γ phase,which causes more Re and Mo partition into the γ＇ phase,increasing the absolute value of mismatch and the rafting rate of the γ＇ phase.

Heavy-ion and pulsed-laser single event effects in 130-nm CMOS-based thin/thick gate oxide anti-fuse PROMs

Single event effects of 1-T structure programmable read-only memory(PROM) devices fabricated with a 130-nm complementary metal oxide semiconductorbased thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset(SEU) for radiationhardened PROMs were measured using a linear energy transfer(LET) ranging from 9.2 to 95.6 MeV cm^2mg^(-1).The result indicated that the LET threshold for a dynamic bit upset was ～ 9 MeV cm^2mg^(-1), which was lower than the threshold of ～ 20 MeV cm^2mg^(-1) for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing209 Bi ions with extremely high LET values(～ 91.6 MeV cm^2mg^(-1)) and large ion fluence(～ 1×10~8 ions cm^(-2)). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device.This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a ^(181)Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CRèME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit.

Comparison of perceived pain and patients’ satisfaction with traditional local anesthesia and single tooth anesthesia: A randomized clinical trial

BACKGROUND Contemporary innovations in the area of local anesthesia have attempted to provide an absolutely pain free experience for patients.Since the introduction of Computer-Controlled Local Anesthetic Delivery Systems to dentistry,many studies have compared its efficacy and safety to conventional anesthesia.However,very few studies have compared single tooth anesthesia(STA)and traditional local anesthesia.AIM To compare pain rating,changes in blood pressure,and heart rate during the local anesthetic injection.The secondary objectives were to measure the patients’level of satisfaction and the differences in anesthetic efficiency between the STA system and traditional local infiltration.METHODS A randomized controlled trial was conducted and a total of 80 patients with dental restorative needs were enrolled for the study.The patients were evaluated for their general physical status and oral clinical findings before enrollment.Information regarding perceived pain,changes in heart rate and blood pressure,and patients’satisfaction was collected using an electronic data form and was analyzed using paired and unpaired t-tests.RESULTS No significant difference was noted in perceived pain(P=0.59)and systolic blood pressure(P=0.09)during anesthetic injection using both traditional and STA techniques.STA patients had a significantly higher heart rate during anesthesia,although a statistically significant difference was noted among the traditional anesthesia and the STA groups even before anesthesia.During the restorative procedure,less pain was perceived by STA patients on the Wong-Baker FACES pain scale,which was statistically significant(P<0.001).Analyses of post-procedure patient responses showed that STA patients had a significantly better treatment experience and preferred to have the same method of injection in the future(P=0.04).CONCLUSION STA system can provide less painful and more comfortable restorative treatment procedures in comparison to the traditional infiltration technique.

Effect of solidification parameters on the microstructures of a single crystal Ni-based superalloy AM3

A single crystal Ni-based superalloy AM3 was processed at withdraw rates of 3.5, 10, 50, 100, 200, and 500 μm·s-1, respectively.The as-cast microstructures and solidification segregation ratio were characterized with various withdraw rates.The shape and size of carbide microstructures were determined.As expected, the primary and secondary dendrite arm spacings (PDAS and SDAS) decrease with the increase of withdraw rate.The highest volume fraction of eutectic γ/γ' is observed at the 100 μm·s-1 withdraw rate.The volume fraction of eutectic γ/γ' does not appear to be a strong function of the withdraw rate.With increasing withdraw rate, interface morphologies change in the sequence of planar, cellular, and dendrite.There is a general refinement of the microstructure as the withdraw rate increases.EPMA analysis showed that withdraw rate does not have obvious influence on the segregation of elements.