307 research outputs found

    Experimental and quantum chemical calculations on corrosion inhibition of mild steel by two furan derivatives

    Get PDF
    Two furan derivatives namely 5-methylfurfurylamine (MFA) and furfurylamine (FAM) were investigated as corrosion inhibitors for mild steel in 1 M HCl. The corrosion inhibition efficiencies (IE) were measured at 0.005M of the inhibitors using electrochemical potentiodynamic polarization measurements. The studied furan derivatives inhibit mild steel corrosion in acidic medium. The MFA shows higher inhibition efficiency of 84.77% compared to FAM of 41.75%. Quantum chemical calculations were performed at the B3LYP/6-311++G(d,p) level of density functional theory (DFT). Several quantum parameters were calculated to study the correlation between the molecular structures and the corrosion inhibition performance of the inhibitors. The MFA inhibitor shows higher HOMO energy, softness (S), fraction of electrons transferred (ΔN), and lower energy gap (ΔE) compared to the FAM. This result indicates a better corrosion inhibition performance of the MFA inhibitor. The results show that the calculated values of the quantum parameters using DFT calculations are consistent with the experimental findings

    Estimating hospital costs of catheter‐associated urinary tract infection

    Get PDF
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100140/1/jhm2079.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/100140/2/jhm2079-sup-0002-suppinfo.pd

    Gestational Sac Aspiration of Heterotopic Ectopic Pregnancy in a Cesarean Section Scar

    Full text link
    Background: This article describes a case of heterotopic pregnancy that included a normal twin intrauterine pregnancy and one cesarean section (CS) scar pregnancy diagnosed at 6 weeks of gestation. Ultrasound-guided aspiration of the ectopic gestational sac was performed, and the concurrent twin intrauterine pregnancy (IUP) was preserved successfully. The patient was a 50-year-old woman with secondary infertility. Case: The patient underwent in vitro fertilization and embryo transfer using a donor-egg program to achieve pregnancy with her current partner. At 6-weeks' gestation, she underwent a transvaginal ultrasound scan (US) examination showing a viable twin IUP with a third gestational sac with viable embryo located low within the anterior wall of the uterus. The appearance was consistent with a cesarean scar ectopic pregnancy. This was confirmed on a subsequent US 1 week later. She desired to continue the intrauterine pregnancy. US-guided aspiration of the cesarean scar ectopic pregnancy was attempted. The treatment was successful. Results: The twin pregnancy progressed without further complications. Conclusions: Heterotopic CS ectopic pregnancy can be successfully treated with transvaginal US-guided aspiration. (J GYNECOL SURG 29:317)Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140090/1/gyn.2012.0026.pd

    Predictive model of 2-cyclohexylthiophene for corrosion inhibition in mild steel using computational method

    Get PDF
    Corrosion inhibition activity of 2-cyclohexylthiophene (2CHT) for mild steel in acidic media was predicted using QSAR tool. The model used two descriptors namely; Moran autocorrelation of lag4 weighted by mass (MATS4M) which explained the linearity and branching of the compounds and largest eigen values n3 of burden matrix weighted by mass (SPMAX3-Bh(m)) describes the nature and size of the neighboring atom. The modeling results revealed the potential of the compounds as a good corrosion inhibitor with percentage inhibition efficiency (%IE) of 76.5%. Quantum chemical calculation using DFT with 6-311G++(d,p) basis was used to evaluate the performance of the predicted compound as corrosion inhibitor by quantum chemical parameters such as EHUMO, ELUMO, Energy gap (Egap), hardness (?), softness (S), dipole moment (µ), electronegativity (X), electron affinity (A), ionization energy (I) and total energy (TE). The results obtained from quantum chemical parameters were found to be consistent with predicted result

    Differential participation of plant ribosomal proteins from the small ribosomal subunit in protein translation under stress

    Get PDF
    Abstract Upon exposure to biotic and abiotic stress, plants have developed strategies to adapt to the challenges imposed by these unfavorable conditions. The energetically demanding translation process is one of the main elements regulated to reduce energy consumption and to selectively synthesize proteins involved in the establishment of an adequate response. Emerging data have shown that ribosomes remodel to adapt to stresses. In Arabidopsis thaliana, ribosomes consist of approximately eighty-one distinct ribosomal proteins (RPs), each of which is encoded by two to seven genes. Recent research has revealed that a mutation in a given single RP in plants can not only affect the functions of the RP itself but can also influence the properties of the ribosome, which could bring about changes in the translation to varying degrees. However, a pending question is whether some RPs enable ribosomes to preferentially translate specific mRNAs. To reveal the role of ribosomal proteins from the small subunit (RPS) in a specific translation, we developed a novel approach to visualize the effect of RPS silencing on the translation of a reporter mRNA (GFP) combined to the 5’UTR of different housekeeping and defense genes. The silencing of genes encoding for NbRPSaA, NbRPS5A, and NbRPS24A in Nicotiana benthamiana decreased the translation of defense genes. The NbRACK1A-silenced plant showed compromised translations of specific antioxidant enzymes. However, the translations of all tested genes were affected in NbRPS27D-silenced plants. These findings suggest that some RPS may be potentially involved in the control of protein translation

    Artificial Intelligence: Serving American Security and Chinese Ambitions

    Get PDF
    In recent years artificial intelligence has entered a new era, which gives rise to many hopes for powerful states such as the United States and China. In this paper, we analyze the importance and role of artificial intelligence in technological development in each of the two countries on the one hand, and its influence on China-American relations in terms of technological and geopolitical conflict

    Performance optimisation of the MAC protocol with multiple contention slots in MIMO ad hoc networks

    Get PDF
    The multiple-input multiple-output (MIMO) technique can be used to improve the performance of ad hoc networks. Various medium access control (MAC) protocols with multiple contention slots have been proposed to exploit spatial multiplexing for increasing the transport throughput of MIMO ad hoc networks. However, the existence of multiple request-to-send/clear-to-send (RTS/CTS) contention slots represents a severe overhead that limits the improvement on transport throughput achieved by spatial multiplexing. In addition, when the number of contention slots is fixed, the efficiency of RTS/CTS contention is affected by the transmitting power of network nodes. In this study, a joint optimisation scheme on both transmitting power and contention slots number for maximising the transport throughput is presented. This includes the establishment of an analytical model of a simplified MAC protocol with multiple contention slots, the derivation of transport throughput as a function of both transmitting power and the number of contention slots, and the optimisation process based on the transport throughput formula derived. The analytical results obtained, verified by simulation, show that much higher transport throughput can be achieved using the joint optimisation scheme proposed, compared with the non-optimised cases and the results previously reported

    Modelling the impact of interventions on imported, introduced and indigenous malaria infections in Zanzibar, Tanzania

    Get PDF
    Malaria cases can be classified as imported, introduced or indigenous cases. The World Health Organization's definition of malaria elimination requires an area to demonstrate that no new indigenous cases have occurred in the last three years. Here, we present a stochastic metapopulation model of malaria transmission that distinguishes between imported, introduced and indigenous cases, and can be used to test the impact of new interventions in a setting with low transmission and ongoing case importation. We use human movement and malaria prevalence data from Zanzibar, Tanzania, to parameterise the model. We test increasing the coverage of interventions such as reactive case detection; implementing new interventions including reactive drug administration and treatment of infected travellers; and consider the potential impact of a reduction in transmission on Zanzibar and mainland Tanzania. We find that the majority of new cases on both major islands of Zanzibar are indigenous cases, despite high case importation rates. Combinations of interventions that increase the number of infections treated through reactive case detection or reactive drug administration can lead to substantial decreases in malaria incidence, but for elimination within the next 40 years, transmission reduction in both Zanzibar and mainland Tanzania is necessary
    corecore