232 research outputs found

    Low-power micro-scale CMOS-compatible silicon sensor on a suspended membrane.

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    In this paper we describe a new, simple and cheap silicon device operating at high temperature at a very low power of a few mW. The essential part of the device is a nano-size conductive link 10-100 nm in size (the so-called antifuse) formed in between two poly-silicon electrodes separated by a thin SiO2 layer. The device can be utilized in chemical sensors or chemical micro-reactors requiring high temperature and very low power consumption e.g. in portable, battery operated systems. As a direct application, we mention a gas sensor (i.e. Pellistor) for hydrocarbons (butane, methane, propane, etc.) based on temperature changes due to the catalytic combustion of hydrocarbons. The power consumed by our device is at about 2% of the power consumed by conventional Pellistors

    Perioperative management of patients undergoing pancreaticoduodenectomies (PD). Surgical clinic no. III Cluj expertise

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    Clinica Chirurgie III, Institutul Regional de Gastroenterologie si Hepatologie, UMF ā€œIuliu Hatieganuā€ Cluj-Napoca, RomĆ¢nia, Al XIII-lea Congres al Asociației Chirurgilor ā€žNicolae Anestiadiā€ și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ā€V.M.Guțuā€ din Republica MoldovaIntroducere: Ǝn 2009, Ć®n Clinica Chirurgie III Cluj-Napoca a fost introdus un protocol care cuprinde aspecte legate de pregătirea preoperatorie a pacienților pentru DPC, de tactica și tehnica intraoperatorie, și tratament postoperator. Material si metode: Studiul Ć®nrolează 444 pacienti cu DPC operați Ć®n clinica Ć®ntre 2009-2018, Ć®mpărțiți Ć®n două loturi: 2009-2015 și 2016-2018. Au fost urmăriți factorii incriminați Ć®n apariția principalelor complicații postoperatorii, rezultatele fiind comparate cu cele obținute Ć®nainte de 2009. InformaÅ£iile s-au colectat utilizĆ¢nd Excel 2009, analiza statistică efectuandu-se cu software-ul R v3.2.4. Rezultate: Nu am obtinut reducerea semnificativă a morbidității (53% Ć®nainte de 2009, 45,6% Ć®ntre 2009-2015 și 42% Ć®ntre 2016- 2018), Ć®nsă a scăzut rata de apariție a fistulei pancreatice (de la 10% la 9,06%, respectiv 7,5%) și a stazei gastrice (de la 43% la 20,47%, respectiv 12,8%). Hemoragia bontului pancreatic a apărut mai frecvent (de la 2%, la 6,71%, respectiv 7,2%). Mortalitatea s-a redus semnificativ (de la 11,9%, la 6,04%, respectiv 3,99%), datorită scăderii fistulelor pancreatice grad C. Concluzie: Implementarea protocolului de pregătire a DPC și-a dovedit utilitatea, iar preocuparea de Ć®mbunătațire a acestuia, prin adaptarea la literatură și la propria experiență rămĆ¢ne o prioritate.Introduction: In 2009, a protocol was introduced at the Surgical Clinic III Cluj-Napoca, which included aspects related to preoperative preparation of patients for PD, intraoperative tactics and technique, and postoperative treatment. Material and Method: The study includes 444 patients with PD operated in the clinic between 2009-2018, divided into two batches: 2009-2015 and 2016-2018. We followed the factors involved in the occurrence of the main postoperative complications and the results were compared with those we obtained before 2009. The information was collected using Excel 2009, the statistical analysis being performed with the software R v3.2.4. Results: We have not achieved a significant decrease in morbidity (53% before 2009, 45.6% between 2009-2015 and 42% between 2016-2018), but decreased the rate of pancreatic fistula (from 10% to 9, 06% and 7.5% respectively) and gastric stasis (from 43% to 20.47% and 12.8% respectively). Pancreas bleeding occurred more frequently (from 2% to 6.71% and 7.2%, respectively). Mortality was significantly reduced (from 11.9% to 6.04% and 3.99%, respectively) due to the reduce rate of grade C pancreatic fistulae. Conclusion: Implementation of the protocol has proven useful and the concern for improvement by adapting it to literature and our experience remains a priority

    The laparoscopic treatment of perforated duodenal ulcer in Romania ā€“ a multicentric study

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    Clinica Chirurgie 2, Timișoara, RomĆ¢nia, Clinica Chirurgie, Spitalul de Urgență, București, Al XI-lea Congres al Asociației Chirurgilor ā€žNicolae Anestiadiā€ din Republica Moldova și cea de-a XXXIII-a Reuniune a Chirurgilor din Moldova ā€žIacomi-Răzeșuā€ 27-30 septembrie 2011Aims. This retrospective study was evaluated the results of laparoscopic treatment of the perforated duodenal ulcer (PDU) in 6 Romanian centres with an important experience in laparoscopic surgery.Methods. Between 2000 and 2010, 221 patients (38 females and 183 men) aged from 18 to 78 years, were operated laparoscopicaly for PDU, by using 3 (66.0%), 4 (27%) or 5 (7.0%) trocars. Forty six (20.8%) of them had a weak, 143(64.7%) an important and 32(14.5%) a grave peritonitis. Procedures performed were: simple suture 84(38.1%) patients, suture with epiplonoplasty 135(61.1%) patients, only epiplonoplasty 1(0.4%) patients, excision with suture 1(0.4%) patients. All patients had abundant peritoneal cavity washing and tub drainage (1-3 tubs).Results. The interventions lasted between 30 and 120 min, with an average of 63 min. No mortality was reported. Postoperative oral nutrition began after 24 hours for 114(51.6%) patients and after intestinal transit has restarted for 107(48.4%) patients. The intestinal transit has restarted after 1-6 days (average 3.5 days), depending of the gravity of peritonitis. Complications were: parietal infections 3 (1.3%), duodenal fistula 1 (0.4%), abdominal abcesses 1(0.4%), digestive haemorrhage 1(0.4%) and duodenal stenosis 1 (0.4%). Hospitalization lasted between 2 and 13 days (average 5.5 days). In comparison with open techniques, patients had the same intravenous perfusions, less pain, less antibiotics, less dressings, less complications during postoperative evolution. Conclusion. Laparoscopic treatment of PDU is safe even in case of severe peritonitis, with faster patientā€™s recovery. with less complications and with less postoperative medical care than open procedures. Aims. This retrospective study was evaluated the results of laparoscopic treatment of the perforated duodenal ulcer (PDU) in 6 Romanian centres with an important experience in laparoscopic surgery.Methods. Between 2000 and 2010, 221 patients (38 females and 183 men) aged from 18 to 78 years, were operated laparoscopicaly for PDU, by using 3 (66.0%), 4 (27%) or 5 (7.0%) trocars. Forty six (20.8%) of them had a weak, 143(64.7%) an important and 32(14.5%) a grave peritonitis. Procedures performed were: simple suture 84(38.1%) patients, suture with epiplonoplasty 135(61.1%) patients, only epiplonoplasty 1(0.4%) patients, excision with suture 1(0.4%) patients. All patients had abundant peritoneal cavity washing and tub drainage (1-3 tubs). Results. The interventions lasted between 30 and 120 min, with an average of 63 min. No mortality was reported. Postoperative oral nutrition began after 24 hours for 114(51.6%) patients and after intestinal transit has restarted for 107(48.4%) patients. The intestinal transit has restarted after 1-6 days (average 3.5 days), depending of the gravity of peritonitis. Complications were: parietal infections 3 (1.3%), duodenal fistula 1 (0.4%), abdominal abcesses 1(0.4%), digestive haemorrhage 1(0.4%) and duodenal stenosis 1 (0.4%). Hospitalization lasted between 2 and 13 days (average 5.5 days). In comparison with open techniques, patients had the same intravenous perfusions, less pain, less antibiotics, less dressings, less complications during postoperative evolution. Conclusion. Laparoscopic treatment of PDU is safe even in case of severe peritonitis, with faster patientā€™s recovery. with less complications and with less postoperative medical care than open procedures

    Cellulose acetate membranes functionalized with resveratrol by covalent immobilization for improved osseointegration

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    Covalent immobilization of resveratrol onto cellulose acetate polymeric membranes used as coating on a Mg-1Ca-0.2Mn-0.6Zr alloy is presented for potential application in the improvement of osseointegration processes. For this purpose, cellulose acetate membrane is hydrolysed in the presence of potassium hydroxide, followed by covalent immobilization of aminopropyl triethoxy silane. Resveratrol was immobilized onto membranes using glutaraldehyde as linker. The newly synthesised functional membranes were thoroughly characterized for their structural characteristics determination employing X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (FT-IR), Raman spectroscopy, thermogravimetric analysis (TGA/DTG) and scanning electron microscopy (SEM) techniques. Subsequently, in vitro cellular tests were performed for evaluating the cytotoxicity biocompatibility of synthesized materials and also the osseointegration potential of obtained derivatised membrane material. It was demonstrated that both polymeric membranes support viability and proliferation of the pre-osteoblastic MC3T3-E1 cells, thus providing a good protection against the potential harmful effects of the compounds released from coated alloys. Furthermore, cellulose acetate membrane functionalized with resveratrol exhibits a significant increase in alkaline phosphatase activity and extracellular matrix mineralization, suggesting its suitability to function as an implant surface coating for guided bone regeneration

    Measuring and Estimating GFR and Treatment Effect in ADPKD Patients: Results and Implications of a Longitudinal Cohort Study

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    Trials failed to demonstrate protective effects of investigational treatments on glomerular filtration rate (GFR) reduction in Autosomal Dominant Polycystic Kidney Disease (ADPKD). To assess whether above findings were explained by unreliable GFR estimates, in this academic study we compared GFR values centrally measured by iohexol plasma clearance with corresponding values estimated by Chronic Kidney Disease Epidemiology Collaboration (CKD-Epi) and abbreviated Modification of Diet in Renal Disease (aMDRD) formulas in ADPKD patients retrieved from four clinical trials run by a Clinical Research Center and five Nephrology Units in Italy. Measured baseline GFRs and one-year GFR changes averaged 78.6Ā±26.7 and 8.4Ā±10.3 mL/min/1.73 m2 in 111 and 71 ADPKD patients, respectively. CKD-Epi significantly overestimated and aMDRD underestimated baseline GFRs. Less than half estimates deviated by <10% from measured values. One-year estimated GFR changes did not detect measured changes. Both formulas underestimated GFR changes by 50%. Less than 9% of estimates deviated <10% from measured changes. Extent of deviations even exceeded that of measured one-year GFR changes. In ADPKD, prediction formulas unreliably estimate actual GFR values and fail to detect their changes over time. Direct kidney function measurements by appropriate techniques are needed to adequately evaluate treatment effects in clinics and research

    Progress of the IAHE Nuclear Hydrogen Division on international hydrogen production programs

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    This paper presents recent activities of the IAHE Nuclear Hydrogen Division and associated research advances in Canada, China, France, Germany, Poland, and Romania on programs and major initiatives on large-scale hydrogen production and utilization. Germany and France have made significant advances in high temperature steam electrolysis (HTSE). Germany is going to demonstrate a 3-kW steam electrolyzer and 100-kW Hybrid Sulfur Cycle powered by solar energy soon. France operated several HTSE 25-cell stacks at various operating points. Recently, a HTSE packaged system has been built, containing this 25-cell stack and other Balance of Plant components. At 700 Ā°C, this system produces 1.2 Nm3/h of H2 with a total electrical consumption of 3.9 kWh/Nm3, achieving 92% of efficiency (electrical consumption of the system vs HHV of the produced hydrogen). It demonstrates that a 150 Ā°C heat source temperature is sufficient for the steam generation, and that a slightly exothermic operating mode of the stack is sufficient to preheat the inlet gas up to 700 Ā°C and compensate the heat losses of the system. China has also made significant progress in developing the HTSE process at a hydrogen production rate of 105 dm3/h and the thermochemical Sulfurā€“Iodine (SI) cycle at the rate of 60 dm3/h, which already achieved the goal of China's HTR-PM Demonstration Nuclear Power Plant Project. The components and facilities were developed and tested in Tsinghua University. Romania is collaborating with Canada on nuclear hydrogen production with the thermochemical Cuā€“Cl cycle. The individual unit operations of the Cuā€“Cl cycle have been verified experimentally. Research on integration of a laboratory scale system to produce 3 kg of hydrogen per day is underway at the University of Ontario Institute of Technology in Oshawa, Ontario. Poland has developed advanced simulation capabilities for Solid Oxide Fuel/Electrolysis Cells for hydrogen peak energy storage as well as laboratory scale experiments focused on solid oxide and molten carbonate fuel cells. This paper presents a review of activities of members of the IAHE Nuclear Hydrogen Division in these six countries

    Investigations on the properties of a two-dimensional nanopatterned metallic film

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    This paper presents some investigations of the effect of nanopatterning on the properties of aluminum layer deposited by sputtering. UV-Nanoimprint Lithography technique has been used for the realization of a 2D array of nanostructures (pillars) in aluminum film characterized by cylindrical shape and the following structural parameters: diameter between 400 nm and 490 nm, depth between 320 nm and 420 nm and periodicity of 1.1 Ī¼ m, which have been revealed by SEM and AFM measurements. The UV-Vis transmission, reflection and photoluminescence measurements have evidenced the effect of the nanopatterning on the optical properties of the Al layer

    4-Phenylbutyric acid treatment rescues trafficking and processing of a mutant surfactant protein C

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    Mutations in the SFTPC gene, encoding surfactant proteinā€“C (SP-C), are associated with interstitial lung disease (ILD). Knowledge of the intracellular fate of mutant SP-C is essential in the design of therapies to correct trafficking/processing of the proprotein, and to prevent the formation of cytotoxic aggregates. We assessed the potential of a chemical chaperone to correct the trafficking and processing of three disease-associated mutant SP-C proteins. HEK293 cells were stably transfected with wild-type (SP-C(WT)) or mutant (SP-C(L188Q), SP-C(Ī”exon4), or SP-C(I73T)) SP-C, and cell lines with a similar expression of SP-C mRNA were identified. The effects of the chemical chaperone 4-phenylbutyric acid (PBA) and lysosomotropic drugs on intracellular trafficking to the endolysosomal pathway and the subsequent conversion of SP-C proprotein to mature peptide were assessed. Despite comparable SP-C mRNA expression, proprotein concentrations varied greatly: SP-C(I73T) was more abundant than SP-C(WT) and was localized to the cell surface, whereas SP-C(Ī”exon4) was barely detectable. In contrast, SP-C(L188Q) and SP-C(WT) proprotein concentrations were comparable, and a small amount of SP-C(L188Q) was localized to the endolysosomal pathway. PBA treatment restored the trafficking and processing of SP-C(L188Q) to SP-C(WT) concentrations, but did not correct the mistrafficking of SP-C(I73T) or rescue SP-C(Ī”exon4). PBA treatment also promoted the aggregation of SP-C proproteins, including SP-C(L188Q). This study provides proof of the principle that a chemical chaperone can correct the mistrafficking and processing of a disease-associated mutant SP-C proprotein

    A sequence variant associating with educational attainment also affects childhood cognition

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    Only a few common variants in the sequence of the genome have been shown to impact cognitive traits. Here we demonstrate that polygenic scores of educational attainment predict specific aspects of childhood cognition, as measured with IQ. Recently, three sequence variants were shown to associate with educational attainment, a confluence phenotype of genetic and environmental factors contributing to academic success. We show that one of these variants associating with educational attainment, rs4851266-T, also associates with Verbal IQ in dyslexic children (P=4.3 x 10(-4), beta=0.16 s.d.). The effect of 0.16 s.d. corresponds to 1.4 IQ points for heterozygotes and 2.8 IQ points for homozygotes. We verified this association in independent samples consisting of adults (P=8.3 x 10(-5), beta=0.12 s.d., combined P=2.2 x 10(-7), beta=0.14 s.d.). Childhood cognition is unlikely to be affected by education attained later in life, and the variant explains a greater fraction of the variance in verbal IQ than in educational attainment (0.7% vs 0.12%,. P=1.0 x 10(-5))
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