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Ecological Processes 2017年第1期6卷 184-191页

作者： Petru Spataru Francisco Fernandez Joseph W.sista Tudor Spataru Oxana Spinu Igor Povar Institute of Chemistry of the Academy of Sciences of Moldova 3 Academiei str.ChisinauMD 2028Republic of Moldova Natural Sciences Department Hostos Community College500 Grand ConcourseBronxNY 10451USA Chemistry Department Columbia University3000 BroadwayNew YorkNY 10027USA.

Introduction:The influence of the interaction of calcium carbonate(CaCO3)and surface-active substances(SAS;surfactants)with different chain lengths and cationic and anionic hydrophilic centers has been ***:Laboratory simulations indicate reduced negative influences on cationic SAS nitrification/self-purification processes in the presence of anionic *** suggests the role of complex ionic formation[anionic SAS*cationic SAS]as a cause of this ***-Vis spectra of lauryl sulfate(LS)and of cetyltrimethylammonium(CTMA),as well as of their mixtures in ratios of 2:1 and 1:1,treated by fine particles of CaCO3,display decreased amounts of SAS in analyzed solutions and their presence on the surface of CaCO3 ***-Vis spectra reveal the decomposition of the complex[anionic SAS(SAS-An)*cationic SAS(SAS-Ct)]in solutions when CaCO3 is *** can be bonded by LS through hydrophobic chains,on the surface of CaCO3 ***,CaCO3 modifies the nature of LS and CTMA *** leads to an increased degree of toxicity of cationic SAS in aquatic *** amounts of CTMA in aqueous solutions are diminished in the presence of ammonium ion NH4+(2 mg/L).In the presence of two orders higher concentration of ammonium ion,this effect strongly increases,making the association *** structure of cationic SAS does not influence this *** obtained results have been confirmed both by timed natural aquatic sample analysis and laboratory simulations using water from Moldovan small rivers(Isnovat,Raut,and Bic).Conclusions:UV-Vis spectra and laboratory simulations demonstrate the change due to the addition of calcium *** and laboratory tests of water samples from Isnovat,Bic,and Raut Rivers,establish the cationic SAS negative influence on treatment and self-purification processes.

关键词： Anionic and cationic surface-active substances Calcium carbonate Small rivers Cetyltrimethylammonium Lauryl sulfate Tetrabutylammonium Toxicity Water pollution

Light Induced Green Synthesis of Silver Nanoparticles Using Aqueous Extract of Prunus amygdalus

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Green and Sustainable Chemistry 2016年第1期6卷 26-33页

作者： sista Kameswara Srikar Deen Dayal Giri Dan Bahadur Pal Pradeep Kumar Mishra Siddh Nath Upadhyay Department of Chemical Engineering & Technology Indian Institute of Technology (BHU) Varanasi Varanasi Uttar Pradesh India Tata Steel Jamshedpur Jharkhand India Department of Botany IFTM University Moradabad Uttar Pradesh India

Light driven, photon mediated green synthesis of silver nano-particles (AgNPs) was carried out using aqueous silver nitrate solution (1 mM) and aqueous extract of almond (Prunus amygdalus). Experiments were carried out in dark, diffused sunlight and direct sunlight to study the influence of light intensity as well as by wrapping the reaction tubes with colored cellophane filters (violet, green, yellow and red) to investigate the effect of light color on AgNP synthesis. It was observed that the violet filter enhanced the AgNPs synthesis appreciably. The FTIR spectroscopic analysis confirmed participation of bio-molecules with hydroxyl and amide groups present in the almond extract as reducing and capping or stabilizing agents, respectively. Dynamic light scattering (DLS) studies revealed the particle size distribution of nano-particles as 2 – 400 nm, and scanning electron microscopy (SEM) confirmed their spherical shape with an average size of about 20 nm. Growth analysis of AgNPs revealed an increase in number of nano-particles with time, whereas their rate of growth decreased gradually. The AgNP suspension was stable even beyond 3 weeks.

关键词： AgNPs Nano-Particles Green Synthesis Prunus amygdalus

Green Synthesis of Silver Nanoparticles: A Review

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Green and Sustainable Chemistry 2016年第1期6卷 34-56页

The bio-molecules from various plant components and microbial species have been used as potential agents for the synthesis of silver nanoparticles (AgNPs). In spite of a wide range of bio-molecules assisting in the process, synthesizing stable and widely applicable AgNPs by many researchers still poses a considerable challenge to the researchers. The biological agents for synthesizing AgNPs cover compounds produced naturally in microbes and plants. More than 100 different biological sources for synthesizing AgNPs are reported in the past decade by various authors. Reaction parameters under which the AgNPs were being synthesized hold prominent impact on their size, shape and application. Available published information on AgNPs synthesis, effects of various parameters, characterization techniques, properties and their application are summarised and critically discussed in this review.

关键词： AgNPs Green Synthesis Silver Nano Plant Extract Microbe

Adenocarcinoma of the third duodenal portion:Case report and review of literature

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World Journal of Gastrointestinal Surgery 2012年第1期4卷 23-26页

作者： Federico sista Giuseppe De Santis Antonio Giuliani Emanuela Marina Cecilia Federica Piccione Laura Lancione Sergio Leardi Gianfranco Amicucci General Surgery Department of SurgeryUniversity of L’Aquila

We focus on the diagnostic and therapeutic problems of duodenal adenocarcinoma, reporting a case and reviewing the literature. A 65-year old man with adenocarcinoma in the third duodenal portion was successfully treated with a segmental resection of the third part of the duodenum, avoiding a duodeno-cephalo-pancreatectomy. This tumor is very rare and frequently affects the III and IV duodenal portion. A precocious diagnosis and the exact localization of this neoplasia are crucial factors in order to decide the surgical strategy. Given a non-specificity of symptoms, endoscopy with biopsy is the diagnostic gold standard. Duodeno-cephalo-pancreatectomy (DCP) and segmental resection of the duodenum (SRD) are the two surgical options, with overlapping morbidity (27% vs 18%) and post operative mortality (3% vs 1%). The average incidence of postoperative long-term survival is 100%, 73.3% and 31.6% of cases after 1, 3 and 5 years from surgery, respectively. Long-term survival is made worse by two factors: the presence of metastatic lymph nodes and tumor localization in the proximal duodenum. The two surgical options are radical: DCP should be used only for proximal localizations while SRD should be chosen for distal localizations.

关键词： Duodenal carcinoma Duodeno-cephalo-pancreatectomy Segmental resection Survival III duodenal portion Duodenal embryological development

Systemic inflammation and immune response after laparotomy vs laparoscopy in patients with acute cholecystitis, complicated by peritonitis

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World Journal of Gastrointestinal Surgery 2013年第4期5卷 73-82页

作者： Federico sista Mario Schietroma Giuseppe De Santis Antonella Mattei Emanuela Marina Cecilia Federica Piccione Sergio Leardi Francesco Carlei Gianfranco Amicucci Department of Surgery University of L'Aquila Department of Medicine Health and Environment Sciences University of L'Aquila

AIM: To evaluate acute cholecystitis, complicated by peritonitis, acute phase response and immunological status in patients treated by laparoscopic or open approach. METHODS: From January 2002 to May 2012, we conducted a prospective randomized study on 45 consecutive patients (27 women, 18 men; mean age 58 years). These subjects were taken from a total of 681 patients who were hospitalised presenting similar preoperative findings: acute upper abdominal pain with tenderness, involuntary guarding under the right hypochondrium and/or in the flank; fever higher than 38 ℃, leukocytosis greater than 10 × 10 9 /L or both, and ultrasonographic evidence of calculous cholecystitis possibly complicated by peritonitis. These patients had undergone cholecystectomy for acute calculous cholecystitis,complicated by bile peritonitis. Randomly, 23 patients were assigned to laparoscopic cholecystectomy (LC), and 22 patients to open cholecystectomy (OC). Blood samples were collected from all patients before operation and at days 1, 3 and 6 after surgery. Serum bacteraemia, endotoxaemia, white blood cells (WBCs), WBC subpopulations, human leukocyte antigen-DR (HLA-DR), neutrophil elastase, interleukin-1 (IL-1) and IL-6, and C-reactive protein (CRP) were measured at 0, 30, 60, 90, 120 and 180 min, at 4, 6, 12, 24 h, and then daily (8 A.M.) until post-operative day ***: The two groups were comparable in the severity of peritoneal contamination as indicated by the viable bacterial count (open group = 90% of positive cultures vs laparoscopic group = 87%) and endotoxin level (open group = 33.21 ± 6.32 pg/mL vs laparoscopic group = 35.02 ± 7.23 pg/mL). Four subjects in the OC group (18.1%) and 1 subject (4.3%) in the LC group (P < 0.05) developed intra-abdominal abscess. Severe leukocytosis (range 15.8-19.6/mL) was observed only after OC but not after LC, mostly due to an increase in neutrophils (days 1 and 3, P < 0.05). This value returned to the normal range within 3-4 d after LC and

关键词： Systemic inflammation Immune response Laparoscopy Cholecystectomy Bile peritonitis