超声乳化白内障摘除联合小梁切除术对眼表的影响

目的:采用Keratograph5M眼表综合分析仪比较小梁切除术和超声乳化白内障摘除联合小梁切除术对眼表的影响。方法:纳入原发性闭角型青光眼合并白内障患者62例62眼,按手术方式分为两组:小梁切除术组32例32眼,超声乳化白内障摘除联合小梁切除术组(青白联合手术组)30例30眼。运用Keratograph5M评估术前,术后3d,1、3mo的非侵入性首次泪膜破裂时间(NifBUT)、非侵入性平均泪膜破裂时间(NiaBUT)、泪河高度(TMH)和角膜荧光素染色评分(CFS)。结果:术前两组患者眼表参数比较差异均无统计学意义(P>0.05)。术后3d青白联合手术组的NiaBUT、NifBUT、CFS、TMH最差,分别为10.13±1.48、12.59±1.96s、0.80±0.22分与0.31±0.02mm,变化幅度明显高于小梁切除组(均P<0.05),术后1mo两组的各项指标均有所恢复,但直到术后3mo仍未完全恢复到术前水平。结论:眼表综合分析仪可以客观、精确地用于评估抗青光眼手术后泪膜功能的变化。在术后3mo短期内超声乳化白内障摘除联合小梁切除术比单纯小梁切除术对眼表的影响更为严重,提示在此期间应加强对眼表的护理。

Application of modified primary closure of the pelvic floor in laparoscopic extralevator abdominal perineal excision for low rectal cancer

AIM To introduce a novel,modified primary closure technique of laparoscopic extralevator abdominal perineal excision(LELAPE) for low rectal cancer.METHODS We retrospectively analyzed data from 76 patients with rectal cancer who underwent LELAPE from March 2013 to May 2016.Patients were classified into the modified primary closure group(32 patients) and the biological mesh closure group(44 patients).The total operating time,reconstruction time,postoperative stay duration,total cost,postoperative complications and tumor recur-rence were compared.RESULTS All surgery was successfully performed.The pelvic reconstruction time was 14.6 ± 3.7 min for the modified primary closure group,which was significantly longer than that of the biological mesh closure group(7.2 ± 1.9 min,P < 0.001).The total operating time was not different between the two groups(236 ± 20 min vs 248 ± 43 min,P = 0.143).The postoperative hospital stay duration was 8.1 ± 1.9 d,and the total cost was 9297 ± 1260 USD for the modified primary closure group.Notably,both of these categories were significantly lower in this group than those of the biological mesh closure group(P = 0.001 and P = 0.003,respectively).There were no differences observed between groups when comparing other perioperative data,long-term complications or oncological outcomes.CONCLUSION The modified primary closure method for reconstruction of the pelvic floor in LELAPE for low rectal cancer is technically feasible,safe and cost-effective.

Microstructural evolution during reheating of A356 machining chips at semisolid state

The microstructural evolution of A356 machining chips in the semisolid state was studied at different temperatures and holding times. The results showed that the elongated α-Al grains first recrystallized in the semisolid state and then became globular with a high shape factor(SF). Both the temperature and the holding time clearly affected the grain size and SF. When the heating temperature or holding time was increased, the grain size and SF gradually increased and finally became stable. Moreover, the Vickers hardness of primary α-Al grains gradually decreased with increasing heating temperature. The optimal slurry for semisolid processing, with a good combination of grain size and SF, was obtained when the chips were held at 600℃ for 15 min. The semisolid slurry of A356 chips exhibited a lower coarsening rate of α-Al grains than those produced by most of the conventional semisolid processes. The coarsening coefficient was determined to be 436 μm^3·s^(-1) on the basis of the linear Lifshitz–Slyozov–Wagner(LSW) relationship.

Non-invasive measurement of pan-colonic pressure over a whole digestive cycle:Clinical applications of a capsule-style manometric system

AIM: To study the prolonged colonic motility under normal conditions with a novel capsule-style micro-system and to assess its clinical significance.METHODS: A single use telemetry capsule (10 mm in diameter, 20 mm in length) embedded with a pressure sensor was ingested by the subjects. The sensor is capable of transmitting colonic pressure wirelessly for more than 130 h. The time of capsule entering the segmental colon was detected by ultrasound. The ultrasonic electrodes were mounted on the surface of the ileocecum and navel and at the junction of the left and rectosigmoid colon of the subjects in sequence, which were identified by abdominal X-rays with radiopaque markers. To verify the accuracy and reliability of ultrasonic detection of telemetry capsules at key points of colon, the segmental colonic transit time was simultaneously recorded by using radiopaque markers.RESULTS: The signal lamp showed that all recorders could receive the radio signal transmitted by the telemetry capsule. The X-rays showed that all telemetry capsules were detected successfully when they were passing through the key points of colon. There was a significant correlation between the transit results obtained by ultrasonic detection or by radiopaque markers. Colorectal recording was obtained from 20 healthy subjects during 613 h (411 h during waking, 202 h during sleep). Compared to waking, the number of pressure contractions and the area under pressure contractions were significantly (P < 0.05) decreased during sleep (21 ± 5 h-1 vs 15 ± 4 h-1, 463 ± 54mmHg·s/min vs 342 ± 45 mmHg·s/min). The colonic motility exhibited significant regional variations both in the circadian behavior and in response to waking and meal.CONCLUSION: The capsule-style micro-system is reliable and noninvasive, and may represent a useful tool for the study of physiology and pathology of colonic motor disorders.

Improving interfacial and electrical properties of HfO_(2)/SiO_(2)/p-Si stacks with N_(2)-plasma-treated SiO_(2) interfacial layer

The effect of N_(2)-plasma-treated SiO_(2) interfacial layer on the interfacial and electrical characteristics of HfO_(2)/SiO_(2)/p-Si stacks grown by atomic layer deposition(ALD) was investigated.The microstructure and interfacial chemical bonding configuration of the HfO_(2)/SiO_(2)/Si stacks were also examined by high-resolution transmission electron microscopy(HRTEM) and X-ray photoelectron spectroscopy(XPS).Compared with the samples without N2-plasma treatment,it is found that the samples with N2-plasma treatment have less oxygen vacancy density for SiO_(2) interfacial layer and better HfO_(2)/SiO_(2) interface.In agreement with XPS analyses,electrical measurements of the samples with N2-plasma treatment show better interfacial quality,including lower interface-state density(Dit,9.3 × 1011 cm^(-2)·eV^(-1) near midgap) and lower oxidecharge density(Q_(ox),2.5 × 1012 cm^(-2)),than those of the samples without N_(2)-plasma treatment.Additionally,the samples with N_(2)-plasma treatment have better electrical performances,including higher saturation capacitance density(1.49 μF·cm^(-2)) and lower leakage current density(3.2 × 10^(-6) A·cm^(-2) at V_(g)=V_(fb)-1 V).Furthermore,constant voltage stress was applied on the gate electrode to investigate the reliability of these samples.It shows that the samples with N_(2)-plasma treatment have better electrical stability than the samples without N_(2)-plasma treatment.

Synthesis and performances of poly(butylene-succinate) with enhanced viscosity and crystallization rate via introducing a small amount of diacetylene groups

A cross-linkable comonomer containing a diacetylene group,named dimethyl 4,4＇-（buta-l,3-diyne-l,4-diyl）dibenzoate（DA） was synthesized and copolymerized with dimethyl succinate and 1,4-butanediol to prepare a series of slightly cross-linked PBS copolyesters（PBDASx）.The chemical structure,crystallization and Theological behaviours of PBDASx were well investigated.Compared to neat PBS,PBDASx showed the greatly increased crystallization rate because of the promoting nucleation of the cross-linking domains,and the XRD results indicated that it had no influence on crystallization structure of PBS.The rheological behaviours indicate that PBDASx possessed higher viscosity than neat PBS even at high shear rate and temperature.PBDAS0.3 exhibited better comprehensive properties than neat PBS,which will widen applications of PBS.

Aggregation structures of organic conjugated molecules on their optoelectronic properties

The intimate connection between stacking modes and optoelectronic properties of organic conjugated materials has been discussed from the viewpoints of developing microscopic models and further understanding of their functions and potential applications.In particular,three basal dimer configurations（cofacial configuration,staggered configuration,and crossed configuration） and their respective optical（including radiative and non-radiative） and electrical properties are expatiated in detail.Eventually,we put forward the perspective on achieving the promising laser material that features high fluorescence quantum yield and charge mobility.