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Background Petersen's hernia, which occurs after minimally invasive surgery for gastric cancer, can be reduced by defect closure. This study aimed to demonstrate the incidence of bowel obstruction above Clavien–Dindo classification grade III due to Petersen's hernia between the mesenteric fixation method(MEFIX) and the conventional methods during the 5-year follow-up period after laparoscopic gastric cancer surgery. Methods This prospective, single-blind, non-inferiority randomized controlled trial and multicenter study was conducted at hospitals in Korea. Patients with histologically diagnosed gastric cancer of clinical stage I, II, or III who underwent Roux-en-Y or B- II gastrojejunostomy anastomosis after laparoscopic gastrectomy were enrolled in this study. Patients who met the inclusion criteria were randomly assigned to two groups: a CLOSURE group that underwent Petersen's defect closure method and a MEFIX group that underwent the mesenteric fixation method. Discussion This trial is expected to provide high-level evidence showing that the MEFIX method can quickly and easily close Petersen's defect and reduce postoperative complications compared to the conventional method. It is also expected to be applicable not only after gastric cancer surgery but also after bariatric surgery. Trial registration The MEFIX study protocol was registered in htrp://register.clinicaltrials.gov as NCT05105360 (registration date: November 3, 2021)

Background The aim of this multicenter cohort study was to compare the clinical courses between open and laparoscopic Petersen’s hernia (PH) reduction. Method We retrospectively collected the clinical data of patients who underwent PH repair surgery after gastrectomy for gastric cancer from 2015–2018. Forty patients underwent PH reduction operations that were performed by six surgeons at four hospitals. Among the 40 patients, 15 underwent laparoscopic PH reduction (LPH), and 25 underwent open PH reduction (OPH), including 4 patients who underwent LPH but required conversion to OPH. Results We compared the clinical factors between the LPH and OPH groups. In the clinical course, we found no differences in operation times or intraoperative bowel injury, morbidity, or mortality rates between the two groups (p > 0.05). However, the number of days on a soft fluid diet (OPH vs. LPH; 5.8 vs. 3.7 days, p = 0.03) and length of hospital stay (12.6 vs. 8.2 days, p = 0.04) were significantly less in the LPH group than the OPH group. Regarding postoperative complications, the OPH group had a case of pneumonia and sepsis with multi-organ failure, which resulted in mortality. In the LPH group, one patient experienced recurrence and required reoperation for PH. Conclusion Laparoscopic PH reduction was associated with a faster postoperative recovery period than open PH reduction, with a similar incidence of complications. The laparoscopic approach should be considered an appropriate strategy for PH reduction in selected cases.

Introduction Petersen's hernia (PH) is a potentially fatal complication of bowel infarction that is difficult to treat by laparoscopic reduction. Aim To define predictive computed tomography (CT) profiles to identify PH patients who would be suitable for laparoscopic reduction by a comparative analysis between patients treated by laparoscopic and open reduction. Material and methods We retrospectively collected the clinical data of patients (n = 28) who underwent PH reduction surgery after minimally invasive gastrectomy for gastric cancer in the period 2015-2018 at four training hospitals. We examined the preoperative CT scans to identify the indications for laparoscopic PH reduction. Results We compared the laparoscopic reduction group (laparoscopic group, n = 15) and the open reduction group (open group, n = 13). Patients in the laparoscopic group were younger (55.7 ±10.4) than those in the open group (69.3 ±9.1), but there were no differences in clinical or laboratory findings. We found that there were two CT profiles with significant differences between the open and laparoscopic groups: superior mesenteric vein (SMV) narrowing and small bowel dilation. We found that small bowel dilatation was an independent factor on multivariate analysis for laparoscopic PH reduction. Conclusions We found that small bowel dilatation is the most important CT profile for identifying PH patients contraindicated for laparoscopic reduction. Despite the retrospective design of this study, these CT profiles are expected to define the scope of laparoscopic reduction in PH patients and to establish indications for the laparoscopic approach.

Cyclic polymers are topologically interesting and envisioned as a lubricant material. However, scalable synthesis of pure cyclic polymers remains elusive. The most straightforward way is to recycle a used catalyst for the synthesis of cyclic polymers. Unfortunately, it is demanding because of the catalyst’s vulnerability and inseparability from polymers, which depreciates the practicality of the process. Here, we develop a continuous process streamlined in a circular way that polymerization, polymer separation, and catalyst recovery happen in situ, to dispense a pure cyclic polymer after bulk ring-expansion metathesis polymerization of cyclopentene. It is enabled by introducing silica-supported ruthenium catalysts and a newly-designed glassware. Also, different depolymerization kinetics of the cyclic polymer from its linear analogue is discussed. This process minimizes manual labor, maximizes security of vulnerable catalysts, and guarantees purity of cyclic polymers, thereby showcasing a prototype of a scalable access to cyclic polymers with increased reusability of precious catalysts (≥415,000 turnovers).

Graphene nanoribbons (GNRs) – an emerging family of carbon-based semiconductors – can be precisely synthesised from small molecules such as benzene derivatives through bottom-up approaches. This review outlines a summary of the development of bottom-up synthesis of GNRs in liquid phase. The strategies are classified based on edge structures and widths of the materials, which are the crucial factors for properties of GNRs. In addition, views on challenges in the field and the future outlook are also provided.

Poly-substituted aromatic sulfur compounds are widely found in pharmaceuticals, agrochemicals and organic materials. However, the position that a sulfur moiety can be introduced to is largely restricted to a pre-functionalized site; otherwise, use of electronically biased substrates or auxiliary groups that direct catalysis is required. Here we report a general ortho thiolation of common aryl and heteroaryl iodides via palladium-norbornene cooperative catalysis. Using this approach, an aryl or alky sulfur moiety can be site-selectively introduced at the arene ortho position without using sterically or electronically biased substrates. The arene ipso functionalization is simultaneously achieved through Heck, Suzuki or Sonogashira termination. The reaction is enabled by a unique class of electrophiles in palladium-norbornene cooperative catalysis, which are sulfenamides derived from seven-membered lactams. The broad substrates scope and high chemoselectivity could make this method attractive for synthesis of complex sulfur-containing aromatic compounds., Poly-substituted aromatic sulfur compounds are part of many pharmaceuticals, agrochemicals and organic materials. Here, the authors developed a sulfenamide-enabled ortho-thiolation of aryl iodides via Pd/norbornene cooperative catalysis for the preparation of polysubstituted aromatic sulfur compounds.

Assessment of male fertility is based on the evaluation of sperm. Semen evaluation measures various sperm quality parameters as fertility indicators. However, semen evaluation has limitations, and it requires the advancement and application of strict quality control methods to interpret the results. This article reviews the recent advances in evaluating various sperm-specific quality characteristics and methodologies, with the help of different assays to assess sperm-fertility status. Sperm evaluation methods that include conventional microscopic methods, computer-assisted sperm analyzers (CASA), and flow cytometric analysis, provide precise information related to sperm morphology and function. Moreover, profiling fertility-related biomarkers in sperm or seminal plasma can be helpful in predicting fertility. Identification of different sperm proteins and diagnosis of DNA damage has positively contributed to the existing pool of knowledge about sperm physiology and molecular anomalies associated with different infertility issues in males. Advances in methods and sperm-specific evaluation has subsequently resulted in a better understanding of sperm biology that has improved the diagnosis and clinical management of male factor infertility. Accurate sperm evaluation is of paramount importance in the application of artificial insemination (AI) and assisted reproductive technology (ART). However, no single test can precisely determine fertility; the selection of an appropriate test or a set of tests and parameters is required to accurately determine the fertility of specific animal species. Therefore, a need to further calibrate the CASA and advance the gene expression tests is recommended for faster and field-level applications.

A three-step preparation of a highly water-soluble poly(p-phenylene ethynylene) (PPE) from commercially available starting materials is disclosed. The palladium/norbornene-catalyzed AB–C-type polym...

This experiment was conducted to analyse the effects of flavone supplementation on the preimplantation development of in-vitro produced porcine embryos. During in-vitro development, immature oocytes and early embryos were exposed to different concentrations of flavone (0, 1μM, 25μM, 50 μM, and 100 μM respectively). Results showed that 100 μM of flavone significantly reduced the intracellular ROS levels of oocytes accompanied with a significant rise in GSH level. In parthenogenesis, no significant change was observed in the cleavage rates whether flavone was supplemented in IVM or IVC media. In IVM supplemented group, the blastocyst development rate was significantly enhanced by 1 μM concentration than other groups (51.5% vs. 41.3%, 44.0%, 36.3%, 31.7%; P

Despite the great promise of armchair graphene nanoribbons (aGNRs) as high-performance semiconductors, practical band-gap engineering of aGNRs remains an unmet challenge. Given that width and edge structures are the two key factors for modulating band-gaps of aGNRs, a reliable synthetic method that allows control of both factors would be highly desirable. Here we report a simple modular strategy for efficient preparation of N = 6 aGNR, the narrowest member in the N = 3p (p: natural number) aGNR family, and two unsymmetrically edge-functionalized GNRs that contain benzothiadiazole and benzotriazole moieties. The trend of band-gap transitions among these GNRs parallels those in donor–acceptor alternating conjugated polymers. In addition, post-functionalization of the unsymmetrical heterocyclic edge via C–H borylation permits further band-gap tuning. Therefore, this method opens the door for convenient band-gap engineering of aGNRs through modifying the heteroarenes on the edge., Effective band-gap engineering of armchair graphene nanoribbons calls for control over both width and edge structure. Here, the authors report a modular synthesis of narrow N = 6 armchair graphene nanoribbons whose edges can be unsymmetrically modified with heteroarenes, introducing a simple way to tune band gap.

Bacteria in the genus Polaribacter, belonging to the family Flavobacteriaceae, are typically isolated from marine environments. Polaribacter dokdonensis DSW-5, the type strain of the species, is a Gram-negative bacterium isolated from the East Sea of Korea. Whole genome shotgun sequencing was performed with the HiSeq 2000 platform and paired-end reads were generated at 188-fold coverage. The sequencing reads were assembled into two contigs with a total length of 3.08 Mb. The genome sequences of DSW-5 contain 2,776 proteincoding sequences and 41 RNA genes. Comparison of average nucleotide identities among six available Polaribacteria genomes including DSW-5 suggested that the DSW-5 genome is most similar to that of Polaribacter sp. MED152, which is a proteorhodopsin-containing marine bacterium. A phylogenomic analysis of the six Polaribacter strains and 245 Flavobacteriaceae bacteria confirmed a close relationship of the genus Polaribacter with Tenacibaculum and Kordia. DSW-5's genome has a gene encoding proteorhodopsin and genes encoding 85 enzymes belonging to carbohydrate-active enzyme families and involved in polysaccharide degradation, which may play important roles in energy metabolism of the bacterium in the marine ecosystem. With genes for 238 CAZymes and 203 peptidases, DSW-5 has a relatively high number of degrading enzymes for its genome size suggesting its characteristics as a free-living marine heterotroph.

Retina, one of the highest oxygen demanding tissues, is vulnerable to vascular insufficiencies, and various ocular vascular disorders can cause chronic retinal ischemia. To investigate the pathophysiology, rodent models developed by bilateral common carotid artery occlusion (BCCAO) have been utilized. However, mice lack posterior communicating arteries in the circle of Willis and cannot endure the brain ischemia induced by the bilateral occlusion. A mouse model to better reflect the localized ischemic stress in the retina without affecting the brain is still needed. Here, we established a mouse model of ischemic injury by permanent unilateral common carotid artery occlusion (UCCAO). Adult male mice were subjected to UCCAO, and changes in the ipsilateral retina were examined in comparison with the contralateral retina. Delayed perfusion was observed in the ipsilateral retina right after the occlusion and was not recovered later on. Common features of retinal ischemia were observed: hypoxia-inducible factor (HIF) stabilization; upregulation of hypoxia-responsive genes; altered levels of cytokines and chemokines. Activation of astrocytes and Muller cells in the inner retina was detected at day 2, and thinning of the inner retinal layer became significant at week 10. Together, our model can simulate retinal ischemia with morphological and molecular changes. It can be utilized to investigate pathophysiology of ischemic retinopathies.

Ru–cyclic alkyl amino carbene (Ru–CAAC) olefin metathesis catalysts perform extraordinarily in metathesis macrocyclization and ethenolysis, but previous studies have been limited to the use of five-membered CAAC (CAAC-5) ligands. In this work, we synthesized a different group of ruthenium catalysts with more σ-donating and π-accepting six-membered CAAC (CAAC-6) ligands, and their metathesis activity was probed through initiation studies, ring-closing metathesis (RCM), cross-metathesis, and ethenolysis. These catalysts display higher initiation rates than analogous Ru–CAAC-5 complexes but demonstrate lower activity in RCM and ethenolysis.

To expand the synthetic platform of the palladium-norbornene cooperative catalysis, here we report a general ortho thiolation of aryl and heteroaryl iodides using sulfenamides as a new class of electrophiles. The sulfenamides derived from a ε-tbutyl-lactam were found most efficient to introduce various aryl and methyl sulfur groups at the arene ortho position. The ipso functionalization is achieved through Heck or Suzuki termination. This reaction also provides a convenient access to the corresponding aryl sulfoxides and sulfones via selective oxidation of the ortho thiolation products.

Realization of a highly flexible, lightweight, and high performance flexible supercapacitor was achieved using three-dimensional graphene on flexible graphite-paper. A simple and fast self-assembly approach was utilized for the uniform deposition of chemical vapor deposition (CVD)-grown high quality 3D-graphene powders on a flexible graphite-paper substrate. The fabricated paper-based symmetric supercapacitor exhibited a maximum capacitance of 260 F g −1 (15.6 mF cm −2 ) in a three electrode system, 80 F g −1 (11.1 mF cm −2 ) in a full cell, high capacitance retention and a high energy density of 8.8 Wh kg −1 (1.24 μWh cm −2 ) at a power density of 178.5 W kg −1 (24.5 μW cm −2 ). The flexible supercapacitor maintained its supercapacitor performance well, even under bent, rolled, or twisted conditions, signifying the excellent flexibility of the fabricated device. Our straightforward approach to the fabrication of highly flexible and lightweight supercapacitors offers new design opportunities for flexible/wearable electronics and miniaturized device applications that require energy storage units that meet the demands of the multifarious applications.

Animal models, particularly pigs, have come to play an important role in translational biomedical research. There have been many pig models with genetically modifications via somatic cell nuclear transfer (SCNT). However, because most transgenic pigs have been produced by random integration to date, the necessity for more exact gene-mutated models using recombinase based conditional gene expression like mice has been raised. Currently, advanced genome-editing technologies enable us to generate specific gene-deleted and -inserted pig models. In the future, the development of pig models with gene editing technologies could be a valuable resource for biomedical research.

This study introduces an in situ fabrication of nanoporous hematite with a Ti-doped SiOx passivation layer for a high-performance water-splitting system. The nanoporous hematite with a Ti-doped SiOx layer (Ti-(SiOx /np-Fe2 O3 )) has a photocurrent density of 2.44 mA cm(-2) at 1.23 VRHE and 3.70 mA cm(-2) at 1.50 VRHE . When a cobalt phosphate co-catalyst was applied to Ti-(SiOx /np-Fe2 O3 ), the photocurrent density reached 3.19 mA cm(-2) at 1.23 VRHE with stability, which shows great potential of the use of the Ti-doped SiOx layer with a synergistic effect of decreased charge recombination, the increased number of active sites, and the reduced hole-diffusion pathway from the hematite to the electrolyte.

Herein an efficient bottom-up solution-phase synthesis of N=9 armchair graphene nanoribbons (GNRs) is described. Catalyzed by Pd(PtBu3 )2 , Suzuki-Miyaura polymerization of a simple and readily available triaryl monomer provides a novel GNR precursor with a high molecular weight and excellent solubility. Upon cyclodehydrogenation, the resulting GNR exhibits semiconducting properties with an approximately 1.1 eV band gap (LUMO: -3.52 eV; HOMO: -4.66 eV) as characterized by UV/Vis-NIR spectroscopy and cyclic voltammetry.

Herein, we report a cooperatively palladium/norbornene-catalyzed polymerization, which simplifies the synthesis of functional aromatic polymers, including conjugated polymers. Specifically, an A2 B2 C-type multicomponent polymerization that is based on an ortho amination/ipso alkynylation reaction was developed for the preparation of various amine-functionalized arylacetylene-containing polymers. Within a single catalytic cycle, the amine side chains are site-selectively installed in situ by C-H activation during the polymerization process, which represents a major difference from conventional cross-coupling polymerizations. This "in situ functionalization" strategy enables the modular incorporation of functional side chains starting from simple monomers, thereby conveniently affording a diverse range of functional polymers.

In the last 10 years, porcine somatic cell nuclear transfer to generate transgenic pig has been performed tremendous development with introduction and knockout of many genes. However, efficiency of porcine somatic cell nuclear transfer is still low and embryo transfer (ET) is one of important step for production efficiency. In porcine ET for production of transgenic cloned pig, we can consider many of points to increase production rates. In respect of seasonality and weather, porcine ET usually is not performed in summer and winter. Cloned transgenic embryos must be transferred into reproductive tracts of recipients where embryos are located after natural fertilization with similar estrous cycle. If cloned embryos with 2∼4 cell stage are transferred, they must be transferred into oviducts in periovulatory stage. Number and deposition sites of transferred cloned embryos are important. And we must compare the methods of ET between surgical and non-surgical ones in respect of production efficiency. Sow recipients after natural estrus is most preferred recipients however its cost is must be considered. Here we will review many of current studies about porcine embryo transfer to increase production efficiency of transgenic pigs and strategies for further studies.

The surgical indications for the treatment of gastroesophageal reflux disease (GERD) in patients with esophageal motility disorders have been debated. We report a case of antireflux surgery performed in a patient with absent esophageal motility as categorized by the Chicago classification (2011). A 54-year-old man underwent laparoscopic Toupet fundoplication due to apparent GERD and desire to discontinue all medications. After surgery, his subjective symptoms improved. Furthermore, objective findings including manometry and 24-hour pH-metry also improved. In our experience, antireflux surgery can improve GERD symptoms patients, even with absent esophageal motility.

Previously, we reported the one-pot synthesis of polyacetylene (PA) diblock copolymers which formed various nanostructures via the in situ nanoparticlization of conjugated polymers (INCP), using a two-step protocol based on sequential monomer addition. Herein, we report a much simpler one-shot method for nanostructure formation by the synthesis of PA blocklike copolymers. The blocklike copolymers could be prepared by the one-shot ROMP of comonomers with large differences in their reactivities because the monomers that formed the first block, namely norbornene (NB) derivatives or endo-tricyclo[4.2.2.0]deca-3,9-diene (TD) derivatives, polymerized much faster than the monomers that formed the second PA block, cyclooctatetraene (COT). Owing to their blocklike microstructures, the copolymers formed various nanostructures such as nanospheres, nanocaterpillars, and nanoaggregates depending on the chemical structures of the soluble shell polymers and feed ratio of COT, which formed the insoluble PA core. Using dy...

This study aimed to evaluate the efficacy of post-operative oral nutrition supplementation after major gastrointestinal surgery.A prospective randomized controlled trial was conducted to evaluate 174 subjects who were discharged within 2 weeks after major gastrointestinal surgery. The subjects in the study group were prescribed 400 ml/day of Encover® from the day of discharge for 8 weeks, but no supplementation was allowed in the control group. The primary endpoint was the weight loss rate at 8 weeks after discharge compared with the pre-operative weight, and the secondary endpoints included changes in body weight, body mass index, Patient-Generated Subjective Global Assessment score/grade, hematological/ biochemical parameters, and adverse events evaluated at 2, 4, and 8 weeks after discharge.The weight loss rate at 8 weeks after discharge did not differ between two groups (4.23±5.49% vs 4.80±4.84%, p=0.481). The total lymphocyte count, the level of total cholesterol, total protein, and albumin were significantly higher in the study group after discharge. Diarrhea was the most frequent adverse event, and the incidence of adverse events with a severity score of=3 did not differ between groups (2.3% vs 1.2%).The utility of routine oral nutritional support after major gastrointestinal surgery was not proven in terms of weight loss at 8 weeks after discharge. However, it can be beneficial for early recovery of biochemical parameters.

Feline ovulation time after LH surge have not been defined because its LH surge is occurred by several times of coital vaginal induction and cat has relatively longer time between LH surge and ovulation compared with other mammalian species. This study was performed to investigate the feline ovulation time after LH surge that was induced by hCG injection for superovulation with PMSG. For superovulation, all cats were received an initial injection of PMSG (200 IU, i.m.) followed 80 hrs later with an injection of hCG (200 IU, i.m.). And then, sampling of both ovaries was surgically performed at each 6 different times (10, 18, 22, 26, 29, and 32 hrs) after hCG injection. Cumulus-oocyte-complexes (COCs) were collected from 2 sides of oviducts and ovaries were fixed for ovarian histology. Total 38 COCs were collected only at hCG 32 hrs and no COCs were shown at earlier 5 times. However, in the ovarian histology, corpus haemorrhagicum or corpus luteum was not shown in all groups including ovary at hCG 32 hrs that COCs were collected. In conclusion, it was suggested that feline ovulation was occurred at 29~32 hrs after LH surge and taken relatively long time for CL formation after ovulation.

Previously we reported a one-pot preparation of nano-objects resembling a caterpillar (nanocaterpillar) from polyacetylene (PA) diblock copolymers, via the in situ nanoparticlisation of conjugated polymers (INCP) approach. However, they showed the following limitations: micro-structure of PA block was stereo-random containing mixtures of E and Z polyenes, and their nanostructures were contaminated by nanosphere defects. Herein, we report strategies to prepare not only defect-free nanocaterpillars, but also the stereo-regular PA diblock copolymers. By altering the ROMP temperature, we can control the stereochemistry (E/Z) of the PA block, the degree of chain-transfer reaction and molar mass dispersity. As a result of a suppressed chain-transfer reaction at low temperature, ROMP of cyclooctatetraene (COT) at 0 °C produced defect-free nanocaterpillars containing cis-major PAs and they can be transformed into those containing trans-major PAs by thermal isomerisation. Compared to previously reported ill-defined block copolymers, these well-defined block copolymers lead to an increase in the length of nanocaterpillars and narrower length distribution.

Nanostar and nanonetwork crystals were prepared from fully conjugated poly(3-(2-ethylhexyl)thiophene)-block-polythiophene (P3EHT-b-PT) via a simple INCP process. The structural conformation of the nanocrystals was investigated in detail, revealing that with an increase in the block length of PT, the morphology of the nanocrystals changed from nanospheres to nanorods, nanostars, and to nanonetworks.

This randomized, phase II, multicenter clinical trial was conducted to evaluate the feasibility of laparoscopy-assisted distal gastrectomy (LADG) with D2 lymph node dissection compared with open distal gastrectomy (ODG) for the treatment of advanced gastric cancer (AGC).D2 lymph node dissection has been accepted as standard treatment for AGC. Although LADG is widely performed in early gastric cancer (EGC), the feasibility of LADG in AGC has not been proven yet.Patients with cT2-T4a and cN0-2 (AJCC 7 staging system) distal gastric cancer were randomly but not blindingly assigned to LADG or ODG groups using fixed block sizes with a 1:1 allocation ratio. The primary endpoint was the noncompliance rate of the lymph node dissection, which was used to evaluate feasibility. Secondary endpoints included 3-year disease-free survival (DFS), 5-year overall survival, complications, and surgical stress response.Between June 2010 and October 2011, 204 patients enrolled and underwent either LADG (n = 105) or ODG (n = 99). Of these, 196 patients (100 in LADG and 96 in ODG) were included in the intention-to-treat analysis. There were no significant differences in the overall noncompliance rate of lymph node dissection between LADG and ODG groups (47.0% and 43.2%, respectively; P = 0.648). In the subgroup analysis, the noncompliance rate in the LADG group was significantly higher than the ODG group for clinical stage III disease (52.0% vs 25.0%, P = 0.043). No difference was found in the 3-year DFS rate between the groups (LADG, 80.1%; ODG, 81.9%; P = 0.448). Differences in postoperative complication rates and surgical stress response were found to be insignificant between the 2 arms.LADG was feasible for AGC treatment based on the noncompliance rate of D2 lymph node dissection. Subgroups analysis data suggest that further studies are needed for stage III gastric cancer.

We report a direct one-pot route for the preparation of supramolecules from simple polyacetylene diblock copolymers synthesized by mild ring-opening metathesis polymerization of cyclooctatetraene. This in situ nanoparticlization of conjugated polymer (INCP) approach is advantageous over conventional self-assembly processes because this method does not require any tedious postsynthetic treatments. Also, this direct approach provides intriguing supramolecules with a unique nanostructure resembling a caterpillar. Furthermore, the new supramolecules are highly stable adducts because the polyacetylene core block provides an exceptionally strong driving force for the self-assembly. Even though pristine polyacetylene is unstable in air, the polyacetylene segment in the nanocaterpillar is very stable because it is protected within the shell of the supramolecule.

We evaluated a method for the assessment of bacterial viability that is based on ultraviolet and visible (UV-Vis) spectroscopy analysis. The quantities of intracellular materials inside a cell vary depending on change of bacterial viability by disruption of the membrane integrity. Therefore, normalized optical density in the range of 200–290 nm was analyzed to determine if it varied in samples containing different proportions of live bacteria. Our results indicate that samples containing higher proportions of live bacteria such as Escherichia coli, Bacillus subtilis, and Staphylococcus epidermidis had higher optical densities. In addition, the optical density at 230 nm divided by the optical density at 670 nm was found to have a strong linear correlation with bacterial viability (the R 2 values of E. coli, B. subtilis, and S. epidermidis are 0.9964, 0.9118, and 0.9861, respectively). Our proposed rapid assessment method takes less than three minutes and only requires optical measurements at 230 and 670 nm; therefore, it is simpler and faster than colony counting, fluorochromasia, or the dyeexclusion test. Moreover, our method was applied to bioaerosols, which are currently important issues in public health, microbiology, aerosol science, and other fields. In our study, the bacteria (E. coli) were dispersed into the air using a Collisontype atomizer, and were sampled in sterilized deionized water using an impinger with a pump. According to our method, the viability of E. coli was approximately 55.2%, which was similar to 52.5 ± 4.7% determined from the LIVE/DEAD BacLight bacterial viability assay.

Purpose: Pancreatic leakage is a serious complication of gastrectomy due to stomach cancer. Therefore, we analyzed amylase and lipase concentrations in blood and drainage fluid, and evaluated the volume of drainage fluid to discern their usefulness as markers for the early detection of serious pancreatic leakage requiring reoperation after gastrectomy. Methods: From January 2001 to December 2007, we retrospectively analyzed data from 24,072 patient samples. We divided patients into two groups; 1) complications with pancreatic leakage (CG), and 2) no complications associated with pancreatic leakage (NCG). Values of amylase and lipase in the blood and drainage fluid, volume of the drainage fluid, and relationships among the volumes, amylase values, and lipase values in the drainage fluid were evaluated, respectively in the two groups. Results: The mean amylase values of CG were significantly higher than those of NCG in blood and drainage fluid (P ＜ 0.05). For lipase, statistically significant differences were observed in drainage fluid (P ＜ 0.05). The mean volume (standard deviation) of the drained fluid through the tube between CG (n = 22) and NCG (n = 236) on postoperative day 1 were 368.41 (266.25) and 299.26 (300.28), respectively. There were no statistically significant differences between the groups (P = 0.298). There was a correlation between the amylase and lipase values in the drainage fluid (r = 0.812, P = 0.000). Conclusion: Among postoperative amylase and lipase values in blood and drainage fluid, and the volume of drainage fluid, the amylase in drainage fluid was better differentiated between CG and NCG than other markers. The volume of the drainage fluid did not differ significantly between groups.

There are making many pedestrian piers in the West Coast due to the increase of tourism population. The Coastal and Harbor Design Specifications(2005) are used to design domestic pedestrian piers, but the Specifications produce very conservative design for the pedestrian piers because of the heavy design loads. This paper presents the comparisons and evaluations of several domestic and foreign design criteria to determine the design load of the pedestrian piers. Numerical analyses using finite-element program MIDAS were performed to suggest some of performance-based design sections in pile supported modular pedestrian piers(PSMP). Five of analyses parameters and Four of loading conditions were applied to 324 analyses models. Deflections, stresses, and natural frequencies from the analyses results were investigated to evaluate the design sections. Finally, this study suggests the performance-based design sections of the PSMP based on the specifications and the design parameters considered in this paper.

We grew multi-walled carbon nanotubes (MWCNTs) on a glass fiber air filter using thermal chemical vapor deposition (CVD) after the filter was catalytically activated with a spark discharge. After the CNT deposition, filtration and antibacterial tests were performed with the filters. Potassium chloride (KCl) particles (

Laboratory tests of particle removal were performed with a pair of carbon fiber ionizers installed upstream of a glass fiber air filter. For air flow face velocities of 0.4, 0.6, and 0.8 m/s, the overall particle removal efficiencies of the filter for all submicron particles were 17%, 16%, and 14%, respectively, when the ionizers were not turned on. These values increased to 27%, 23%, and 19%, respectively, when the ionizers were used to generate ions of 6.0 × 10 9 ions/cm 3 in concentration. The carbon fiber ionizers were then installed in front of a glass fiber air filter located in a heating, ventilation, and air-conditioning (HVAC) system. Field tests were performed in a test office room with a total indoor particle concentration of 2.2 × 10 4 particles/cm 3 . When the flow rate was 75 cubic meters per hour (CMH), the steady-state values of the total indoor particle concentrations using the glass fiber air filter with and without ionizers decreased to 0.87 × 10 4 particles/cm 3 and 1.15 × 10 4 particles/cm 3 , respectively, resulting in a 25% decrease of the ionizer effect. When the operation flow rate was increased to 115 and 150 CMH, the effect of the ionizer decreased to 19% and 17%, respectively. These experimental data match the results calculated using a mass-balance model whose parameters were determined from laboratory tests.

The effect of condensational growth, one of the important characteristics for both monitoring and controlling bioaerosols, on bioaerosol culturability was assessed in this study. Three species of bacteria (Staphylococcus epidermidis, Pseudomonas fluorescens, and Escherichia coli) were used. The measured growth factors of the bioaerosols ranged from 1.07 to 1.67 under various conditions and these data coincided with calculated results using both the thermodynamic approach and the moment method. The culturable fractions obtained using an Anderson type impactor were observed to increase as a result the formation of the liquid layer around the bioaerosols via condensational growth of the particle, which correspondingly resulted in both increase of physical collection efficiency and decrease of impaction stress. The culturable fractions of sampled bioaerosols increased up to 43% (for S. epidermidis), 27% (for P. fluorescens), and 12% (for E. coli) by condensational growth, compared to no condensational growth. However, the culturable fraction decreased when the condensational growth was excessive, probably due to heat transfer to the bioaerosols during the condensational process.

The process of waste decomposition releases odors, airborne particles, and bioaerosols; therefore, air quality control at composting facilities is very important to the health of workers and the effective operation of such facilities. Because dielectric barrier discharge (DBD) produces chemical species, it has been used to remove undesired species interesting for environmental applications. In this study, a DBD reactor was applied to a composting facility to simultaneously remove odors, airborne particles and bioaerosols. The power consumption required was below 18.9 W when the flow volume of the pollutant gas was 0.2 L and the concentrations of ammonia, amines, airborne particles, and bioaerosols were 150 (or 75) ppm, 140 ppm, 2.1 × 108 particles/m3, and 1.1 × 104 CFU/m3, respectively. The removal efficiency of contaminants in the air increased as the specific energy densities (SED) increased, with removal efficiencies of up to 80% and 76% being achieved for ammonia and amines. Moreover, the removal efficiency of the overall airborne particles was 75% when 113 J/L of SED was employed, while the bioaerosols removal efficiency was 89% when 38 J/L of SED used.