不同手术及缝合方式治疗中重度宫颈上皮内瘤变的临床观察

目的:探讨中重度宫颈上皮内瘤变(CINⅡ-Ⅲ)行宫颈锥切治疗的不同止血方式。方法分析75例在阴道镜下活检,病理诊断 CINⅡ-Ⅲ患者,其中行宫颈环形电切(LEEP)术治疗的40例,行宫颈冷刀锥切采用二、二、二式(甲、乙、丙、丁)缝合的35例,对比两组手术后的出血、宫颈残端感染、残端愈合、及病理诊断切缘情况。结果 LEEP术中出血超过20 mL者15例,占37.5%;术后宫颈残端感染者10例,占25%;病理诊断切缘阳性者5例,占12.5%;术后2个月残端愈合10例,占25%。宫颈冷刀锥切采用二、二、二式(甲、乙、丙、丁)缝合术后出血超过20 mL者0例,占0%,术后宫颈残端感染者2例,占5.7%;病理诊断切缘阳性者0例,占0%,均明显低于LEEP术组。术后2个月残端愈合35例,占100%,均明显高于LEEP术组。结论宫颈残面采用二、二、二式(甲、乙、丙、丁)缝合应用于宫颈冷刀锥切术,较LEEP术止血效果好,感染机会小,疤痕少,对标本切缘的病理诊断无影响,残端愈合快。

Using genetic algorithms to calibrate a dimethylsulfide production model in the Arctic Ocean

The global climate is intimately connected to changes in the polar oceans. The variability of sea ice coverage affects deep-water formations and large-scale thermohaline circulation patterns. The polar radiative budget is sensitive to sea-ice loss and consequent surface albedo changes. Aerosols and polar cloud microphysics are crucial players in the radioactive energy balance of the Arctic Ocean. The main biogenic source of sulfate aerosols to the atmosphere above remote seas is dimethylsulfide (DMS). Recent research suggests the flux of DMS to the Arctic atmosphere may change markedly under global warming. This paper describes climate data and DMS production (based on the five years from 1998 to 2002) in the region of the Barents Sea (30–35°E and 70–80°N). A DMS model is introduced together with an updated calibration method. A genetic algorithm is used to calibrate the chlorophyll-a (CHL) measurements (based on satellite SeaWiFS data) and DMS content (determined from cruise data collected in the Arctic). Significant interannual variation of the CHL amount leads to significant interannual variability in the observed and modeled production of DMS in the study region. Strong DMS production in 1998 could have been caused by a large amount of ice algae being released in the southern region. Forcings from a general circulation model (CSIRO Mk3) were applied to the calibrated DMS model to predict the zonal mean sea-to-air flux of DMS for contemporary and enhanced greenhouse conditions at 70–80°N. It was found that significantly decreasing ice coverage, increasing sea surface temperature and decreasing mixed-layer depth could lead to annual DMS flux increases of more than 100% by the time of equivalent CO2 tripling (the year 2080). This significant perturbation in the aerosol climate could have a large impact on the regional Arctic heat budget and consequences for global warming.

Elevating the flexibility and operability of dividing-wall distillation columns via feed thermal condition adjustment

Because of the complicated interplay between the prefractionator and main distillation column involved,the black-hole problem might occur and prohibit the assignment of four specifications to dividing-wall distillation columns(DWDCs)(e.g., the three main product compositions plus an impurity ratio in the intermediate product), which lowers terribly process flexibility and operability. In this paper, a feed thermal condition adjustment strategy, achieved by the installation of a pre-heater in feed pipeline, is employed to eliminate the black-hole problem and serve to enhance process flexibility and operability. Through the strong influence to the overall mass and energy balance of the DWDC, the feed thermal condition adjustment can alter the interlinking flows between the thermally coupled prefractionator and main distillation column and work effectively to coordinate their relationship. A DWDC separating a benzene, toluene, and o-xylene mixture is chosen to ascertain the feasibility of the philosophy proposed. The static and dynamic studies demonstrate that the feed thermal condition adjustment is an effective way to refine process design and can completely eliminate the black-hole problem and elevate consequently process flexibility and operability.

Solar Oxidation and Removal of Arsenic from Groundwater Utilizing a Semicircular Section Tubular Photoreactor

A semicircular section tubular photoreactor has been constructed, characterized and applied to the treatment of groundwater contaminated with As（V） by means of the SORAS （solar oxidation and removal of arsenic） technique, using ferrous and citrate salts. The solar concentrator was built with recyclable waste materials： glass tubes from fluorescent lamps and 6-inch diameter PVC pipes cut in half and covered by aluminum foil. The reactor concentrates solar radiation up to 2.8 times its natural intensity. Batch irradiation experiments followed by controlled agitation （shear rate = 30-33 s^-1; 20 min agitation period） showed that the photoreactor accelerates the formation of settleable floccules （Dp 〉 0.5mm）, compared with a fluorescent lamp glass tube alone and a 2 L PET （polyethylene terephthalate） bottle. Irradiation times necessary for floccule formation in the photoreactor, the fluorescent lamp tube and the PET bottle were 15 min, 25 min and 60 min, respectively. Continuous flow experiments using a photoreactor with a photo-collection area of 0.9 m^2 and a hydraulic retention time （equal to the irradiation time） of 15 rain showed that immediate formation of floccules of good settleability occurs when the solution is subjected to moderate agitation （33 s^-1）. An efficiency of 98.36% for As（V） removal was obtained with a final concentration of 16.5 ktg/L in decanted waters. In accordance to these results, the photoreactor is able to treat approximately 130 L/m^2 within a 5-h period with UVA irradiation intensities of 50-70 W/mE.

Synthesis and Crystal Structure of cis-[1,2-Bis(phenyl-thiomethyl)benzene]dichloroplatinum(Ⅱ)·0.5acetonitrile

The title complex was prepared from the reaction of 1,2-bis(phenylthiomethyl)- benzene L with K2PtCl4 at room temperature and its structure has been determined by single-crystal X-ray diffraction. There exist two independent cis-[1,2-bis(phenylthiomethyl)benzene]dichloro- platinum(Ⅱ) [PtCl2L] molecules without significant structural difference and a molecule of acetonitrile in one crystallographic asymmetric unit. Crystallographic data: triclinic, space group Pī, a = 11.010(3), b = 12.080(3), c = 16.095(4) ? = 94.728(5), = 90.129(5), = 99.274(5)? C20H18Cl2NPtS20.5CH3CN, Mr = 608.98, V = 2105(1) ?, Z = 4, Dc = 1.921 g/cm3, (Mo-K) = 7.122 mm1, F(000) = 1172, R = 0.0503 and wR = 0.0848 for 3929 observed reflections with I > 2s(I). The title complex is a neutral molecule in which the central Pt(Ⅱ) ion is four-coordinated with two S-donors of the ligand and two Cl anions, forming a distorted square planar geometry. In the crystal, there exist two kinds of molecular packing patterns. One [PtCl2L] molecule is connected to the other one through the weak interactions of Pt…Pt, Pt…S and Pt…Cl, forming a supramolecular quasi-dimer. The other one complex molecule is connected with the CH3CN molecule by weak Cl…N interaction.

Stereoselective synthesis of cis- and trans-4-acyl-β-lactams from vicinal diketones and ketoaldehydes

4-Acyl-β-lactams are important synthetic intermediates in both pharmaceutical and organic chemistry. Cis- and trans-4-acyl-β- lactams were synthesized stereoselectively from vicinal diketones via the formation of bulky and less bulky diimines as key intermediates, respectively. The diimines reacted with acyl chloride in the presence of triethylamine to give rise to the corre- sponding 4-imino-β-lactams, which were further hydrolyzed to afford 4-acyl-β-lactams. The cis- and trans selectivity is de- pended on the steric hindrance of the imine N-substituents. A series of cis-4-acyl-β-lactams were synthesized from vicinal ketoaldehydes via the formation of their monoimines and diimines as intermediates. Pyruvic aldehyde produced cis-4-acetyl-β- lactams and cis-4-formyl-β-lactams, respectively, through the reactions of its monoimine and diimine with acyl chlorides. Phenylglyoxal generated cis-4-benzoyl-β-lactams via its monoaldimine.

Fabrication of ordered micro- and nano-scale patterns based on optical discs and nanoimprint

A simple method to fabricate one-dimensional(1-D) and two-dimensional(2-D) ordered micro- and nano-scale patterns is developed based on the original masters from optical discs, using nanoimprint technology and soft stamps. Polydimethylsiloxane(PDMS) was used to replicate the negative image of the 1-D grating pattern on the masters of CD-R, DVD-R and BD-R optical discs, respectively, and then the 1-D pattern on one of the PDMS stamps was transferred to a blank polycarbonate(PC) substrate by nanoimprint. The 2-D ordered patterns were fabricated by the second imprinting using another PDMS stamp. Different 2-D periodic patterns were obtained depending on the PDMS stamps and the angle between the two times of imprints. This method may provide a way for the fabrication of complex 2-D patterns using simple 1-D masters.