Surgical management of mesenteric ischemia

The aim of the research was to assess the initial results of the application of “Damage Control Surgery” (DCS) principle in the treatment of acute mesenteric ischemia (AMI). Despite the successes achieved in the surgical treatment of the AMI the lethality rate in this group of patients is still 70-90%. Several surgical options have been reflected until now in literature, but there are few articles on the application of DCS principle in the surgical management of AMI. We present the results of the surgical management of 13 consecutive cases of AMI treated according to the DCS management option (immediate resection of nonviable bowel without the reconstruction of the digestive tract, laparostoma, including VAC-system, stabilizing the patient in the Intensive Care department and eventual elective reconstructive surgery later) between January 2009 and march 2010. Mean age was 67.92±2.48 (48-79) years, with the mean period of time before check-in of 45.62±14.47 hours. Diagnosis was set using the results of D-dimers test, 3D-CT with angiography and laparoscopy. 11 cases of arterial AMI and 2 cases of venous AMI were identified. The primary surgery included resection of the nonviable portion of the intestine: ileum (n=2), jejunum+ileum (n=3), jejunum+ileum+right hemicolonectomy (n=8). The final reconstructive surgery was performed after 50.82± 5.31 hours. The postoperative mortality was 61.53% (died 8 patients). The initial experience demonstrates that the Damage Control Surgery principle can be considered the only surgical option for the treatment of patients with AMI. The final conclusions will be defined after the analysis of a bigger group of patients

The influence of LiF layer abd ZnO nanoparticels addings on the performances of flexible photovoltaic cells based on polymer blends

International audienceFlexible organic solar cells were successfully prepared using spin-coating technique on PET substrates covered with a thick layer of ITO. The goal of this study is to identify the effects of the LiF layer and ZnO nanoparticles mixing in PEDOT:PSS solution and to compare the photovoltaic properties of these „customized” cells PET/ITO/PEDOT:PSS + ZnO nanoparticles/P3HT:PCBM(1:1)/Al, PET/ITO/PEDOT:PSS + ZnO nanoparticles/P3HT:PCBM(1:1)/LiF/Al, with ones of the “conventional” structures, PET/ITO/PEDOT:PSS/P3HT:PCBM(1:1)/Al. The thickness of the LiF layer, deposited by thermal vacuum evaporation, was two nanometers. Composite samples were prepared by adding ZnO nanoparticles into PEDOT:PSS solution, followed by ultrasonication. I-V characteristics were measured in dark and under A.M.1.5 conditions for all samples immediately and after one month from the preparation date. The action spectra measurements revealed that the structures which have a nanometric LiF layer are more stable than those without. Photoelectrical measurements indicate that the ZnO nanoparticles have a positive influence on the conversion efficiency and also to reduce the serial resistance of the structure

„Second look laparatomy” în tratamentul ischemiei mezenterice acute venoase

Nicolae Anestiadi Department of Surgery no. 1, Nicolae Testemitanu SUMPhBackground. Acute mesenteric venous thrombosis (AMVT) - is a rare pathology, which is ≈1 / 1000 cases of acute surgical pathology with lethality up to 25% according to the literature. Objective of the study. To optimize surgical treatment of acute mesenteric venous ischemia (AMVI). Material and Methods. 75 cases of AMI were analyzed. In 12 (16%) cases, TMVA was determined, the ratio M: F = 1.2: 1, mean age - 51.1 ± 5.2 years (95% CI: 39.51–62.85). Intraoperative revision - TMVA with involvement of jejunum (n = 3), ileum (n = 5) and jejunum + ileum (n = 3). Results. The principle of second look laparatomy (SLL) - initiated in the absence of clear delimitation of the segment with venous infarction, systemic heparin therapy is applied starting with the intraoperative period, repeated revision with bowel resection and application of anastomosis or finding of total venous AMVI regression, was used in 6 patients - 50% cases of venous AMVI. Postoperative lethality was zero. As an etiology of AMVT, it was established that hereditary thrombophilia predominated statistically significant (p = 0.0003), including antithrombin deficiency III (n = 7), C and protein S deficiency (n = 3). In all cases, patients were included in the permanent anticoagulant therapy protocol. Conclusion. The SLL in case of venous AMVI significantly reduces the postoperative mortality rate and the volume of the resected intestine, compared to the standard methodology.Introducere. Tromboza mezenterială venoasă acută (TMVA) – este o patologie rar întâlnită, care constituie ≈1/1000 cazuri din patologia acută chirurgicală, cu letalitatea până la 25 %, conform literaturii. Scopul lucrării. Optimizarea tacticii tratamentului chirurgical al ischemiei mezenterice acute (IMA) venoase. Material și Metode. S-a analizat 75 de cazuri de IMA. În 12 (16%) cazuri s-a determinat TMVA, raportul B:F=1.2:1, vârsta medie – 51.1±5.2 ani (95% CI:39.51–62.85). Revizia intraoperatorie –TMVA cu implicarea jejunului (n=3), ileonului (n=5) şi jejun + ileon (n=3). Rezultate. Principiul second look laparatomy (SLL) – inițiat în lipsa delimitării certe a segmentului cu infarct venos, se apilică terapia sistemică cu heparină începând cu perioada intraoperatorie, revizia repetată cu rezecţia intestinului şi aplicarea anastomozei sau constatarea regresiei totale a IMA venoase, a fost utilizat la 6 pacienți – 50% cazuri de IMA venoasă. Letalitatea postoperatorie a fost zero. Ca etiologie a TMVA, s-a stabilit că trombofilia ereditară a predominat statistic semnificativ (p=0.0003), inclusiv deficienţa de antitrombina III (n=7), C și isuficienta de proteină S (n=3). ). În toate cazurile pacienţii au fost incluşi în protocolul de terapie anticoagulantă permanentă. Concluzii. Tactica SLL în caz de IMA venoasă reduce semnificativ rata mortalității postoperatorii și volumul intestinului rezectat, comparativ cu metoda standard

Sodium Alginate-g-acrylamide/acrylic Acid Hydrogels Obtained by Electron Beam Irradiation for Soil Conditioning

Being both a cause and a victim of water scarcity and nutrient deficiency, agriculture as a sustainable livelihood is dependent now on finding new suport solutions. Biodegradable hydrogels usage as soil conditioners may be one of the most effective solutions for irrigation efficiency improvement, reducing the quantity of soluble fertilizers per crop cycle and combating pathogens, due to their versatility assured by both obtaining method and properties. The first goal of the work was the obtaining by electron beam irradiation and characterization of some Sodium Alginate-g-acrylamide/acrylic Acid hydrogels, the second one being the investigation of their potential use as a soil conditioner by successive experiments of absorption and release of two different aqueous nutrient solutions. Alginate-g-acrylamide/acrylic Acid hydrogels were obtained by electron beam irradiation using the linear accelerator ALID 7 at 5.5 MeV at the irradiation doses of 5 and 6 kGy. For this were prepared monomeric solutions that contained 1 and 2% sodium alginate, acrylamide and acrylic acid in ratios of 1:1 and 1.5:1, respectively, for the obtaining of materials with hybrid properties derived from natural and synthetic components. Physical, chemical, structural and morphological characteristics of the obtained hydrogels were investigated by specific analysis using swelling, diffusion and network studies and Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Four successive absorption and release experiments of some synthetic and natural aqueous solutions with nutrients were performed

Nanomaterials Characterization Using Nuclear Methods at IFIN-HH

The aim of this study is to analyze nanostructured materials using Positron Annihilation Spectroscopy (PAS), Nuclear Reaction Analysis (NRA) and Rutherford Backscattering Spectrometry (RBS) nuclear techniques. Three different types of nanomaterials: polymer nanofibers (polyurethane doped with silver nanoparticles), carbon nanowalls (CNW) and InN thin films on yttria-stabilized-zirconia (YSZ) substrate were investigated using these methods. PAS was demonstrated on polymer nanofibers providing information on vacancy defects, RBS was applied on InN thin films providing information regarding the thickness and the stoichiometry of the films. Preliminary NRA results are also presented, showing the possibility of detecting and measuring the hydrogen content in CNW

Degradation by Electron Beam Irradiation of Some Composites Based on Natural Rubber Reinforced with Mineral and Organic Fillers

Composites based on natural rubber reinforced with mineral (precipitated silica and chalk) and organic (sawdust and hemp) fillers in amount of 50 phr were obtained by peroxide cross-linking in the presence of trimethylolpropane trimethacrylate and irradiated by electron beam in the dose range of 150 and 450 kGy with the purpose of degradation. The composites mechanical characteristics, gel fraction, cross-linking degree, water uptake and weight loss in water and toluene were evaluated by specific analysis. The changes in structure and morphology were also studied by Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. Based on the results obtained in the structural analysis, possible mechanisms specific to degradation are proposed. The increasing of irradiation dose to 450 kGy produced larger agglomerated structures, cracks and micro voids on the surface, as a result of the degradation process. This is consistent with that the increasing of irradiation dose to 450 kGy leads to a decrease in crosslinking and gel fraction but also drastic changes in mechanical properties specific to the composites’ degradation processes. The irradiation of composites reinforced with organic fillers lead to the formation of specific degradation compounds of both natural rubber and cellulose (aldehydes, ketones, carboxylic acids, compounds with small macromolecules). In the case of the composites reinforced with mineral fillers the degradation can occur by the cleavage of hydrogen bonds formed between precipitated silica or chalk particles and polymeric matrix also

Influence of PEDOT:PSS layer on the performances of "bulk-heterojunction" photovoltaic cells based on MEH-PPV:PCBM(1:4) polymeric blends

cited By 9Photovoltaic cells having as active layer a mixture between poly[2-[2',5'-bis(2-ethyhexyloxy)phenyl]-1,4-phenylenevinylene]-co-[2-methoxy-5-(2'-ethylexyloxy)-1,4-phenylenevinylene] (MEH-PPV) regioregular polymer and [6,6]-phenyl C 61 butyric acid methyl ester (PCBM) fullerene derivative were prepared on ITO covered optical glass and plastic sheets, as substrates. The samples have the same architecture, the main difference between them being the presence or not of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). For all the prepared structures, the morphological, optical and electrical characterization was carried out, comparatively. The current-voltage (I-V) characteristics in monochromatic light and the action spectra of the prepared structures were recorded, at room temperature. The parameters characterizing photovoltaic cells (short-circuit current, open circuit voltage and fill factor) were calculated and compared for prepared structures with or without PEDOT:PSS "buffer" layer

The influence of lif layer and ZnO nanoparticles addings on the performances of flexible photovoltaic cells based on polymer blends

cited By 24Flexible organic solar cells were successfully prepared using spin-coating technique on PET substrates covered with a thick layer of ITO. The goal of this study is to identify the effects of the LiF layer and ZnO nanoparticles mixing in PEDOT:PSS solution and to compare the photovoltaic properties of these "customized" cells PET/ITO/PEDOT:PSS + ZnO nanoparticles/P3HT:PCBM(1:1)/Al, PET/ITO/PEDOT:PSS + ZnO nanoparticles/P3HT:PCBM(1:1)/LiF/Al, with ones of the "conventional" structures, PET/ITO/PEDOT:PSS/P3HT:PCBM(1:1)/Al. The thickness of the LiF layer, deposited by thermal vacuum evaporation, was two nanometers. Composite samples were prepared by adding ZnO nanoparticles into PEDOT:PSS solution, followed by ultrasonication. I-V characteristics were measured in dark and under A.M.1.5 conditions for all samples immediately and after one month from the preparation date. The action spectra measurements revealed that the structures which have a nanometric LiF layer are more stable than those without. Photoelectrical measurements indicate that the ZnO nanoparticles have a positive influence on the conversion efficiency and also to reduce the serial resistance of the structure