An Experimental Study on the Influence that Failure Number, Specialization, and Domain have on Confidence in Predicting System Failures

Design reviews are typically used for three types of design activities: 1) identifying errors, 2) assessing the impact of the errors, and 3) suggesting solutions for the errors. This experimental study focuses on understanding the second issue as it relates to the number of errors considered, the existence of controls, and the level of domain familiarity of the assessor. A set of design failures and associated controls developed for a completed industry sponsored project is used as the experimental design problem. Non-domain individuals (psychology class students), domain generalists (first year engineering students), and domain specialists (graduate mechanical students) are provided a set of failure modes and asked to estimate the likelihood that the system would still successfully achieve the stated objectives. Primary results from the study include the following: the confidence level for all domain population decreased significantly as the number of design errors increased (largest p-value=0.0793) and this decrease in confidence is more significant as the design errors increase. The impact on confidence is less when solutions (controls) are provided to prevent the errors (largest p-value=0.0334), the confidence decreased faster for domain general engineers as compared to domain specialists (p= The research presents a study on how estimations are made in design reviews. It answers the question on how individuals assess the performance of systems which is necessary to be addressed in order to evaluate the importance of methods such as design reviews and design review tools (FMEA, DFMEA, FTA) used in design engineering. It addresses the challenges faced by the impact of design errors in the design process and how they affect assessment by different types of designers in predicting successful system performance

Synthesis and characterization of oligo/polythiophenes bearing stable radicals

Two categories of verdazyl radical functionalized oligothiophenes have been prepared: 1,5-diisopropyl-6-oxoverdazyl radical directly linked to terthiophene (2.6), and 1,5- diisopropyl-6-oxoverdazyl radical attached to terthiophene through a π system bridge, e.g., pyridine (2.11). Compound radical 2.6 was prepared by a two step process starting with the condensation of terthiophene carboxaldehyde and 2,4-diisopropylcarbonhydrazide bis-hydrochloride to give the tetrazane 2.5, which was subsequently oxidized chemically to give the corresponding verdazyl radical grafted at the 3’ position of the terthiophene moiety. The latter displays excellent stability toward organic solvents and moisture. The electropolymerization of radical 2.6 resulted in the formation of its polymer (poly(2.6)), which was characterized by cyclic voltammetry and infrared spectroscopy. The electrochemical oxidation of the tetrazane, 2.5, yielded surprisingly a poly(terthiophene) bearing verdazyl radical, with similar electrochemical and infrared properties of those found for the polymer produced in the electro-oxidation of the terthiophene bearing verdazyl radical (poly(2.6)). Moreover, the electrochemical oxidation of 2.5 (beyond its oxidation potential of the tetrazane motif) affords the radical 2.6. A similar strategy has been used for the synthesis and the characterization of tetrazane 2.10 and its corresponding verdazyl 2.11.Master's These

Metal-Mediated Vinylogous Nazarov Cyclization Reaction

The Nazarov cyclization reaction has been used as an effective method to synthesize cyclopentanones. While 6-membered ring systems can be available by way of the homo Nazarov variant, 7-membered ring formation involving a Nazarov-type reaction is very rare, and completely unknown thermally. Using the established concept of the ability of the alkyne-Co2(CO)6 moiety to enable the formation of -carbonyl cations and the good stability of this generated cation, 7-membered ring formation via the vinylogous Nazarov reaction with electron deficient enones has been investigated. The desired aryl substituted enyone-Co2(CO)6 complex precursors for the cyclization reaction have been prepared from commercially available starting materials, using a series of reactions that include Sonogashira cross-coupling, desilylation, organolithium reactions with aldehydes, oxidation and complexation reactions. The treatment of the respective complex precursors, using SnCl4 as a suitable Lewis acid, successfully generated cycloheptynone-Co2(CO)6 complexes. The substitution effects have been examined, showing that introducing a bulky group at the alpha-position to the carbonyl enhances the cyclization efficiency by enabling the desired s-trans/s-trans conformation. On the other hand, beta-substituting with an R group other than H atom reduces the reaction rate and allows formation of the desired 7-membered ring only in very low yield. Preparation of appropriate dienynone-Co2(CO)6 complex substrates allowed expansion of the reaction scope to non-aromatic starting materials. Successful reductive decomplexation of the cycloheptynone-Co2(CO)6 unit also was demonstrated

Patterns of plant diversity in seven temperate forest types of Western Himalaya, India

AbstractPlant biodiversity patterns were analyzed in seven temperate forest types [Populus deltoides (PD), Juglans regia, Cedrus deodara, Pinus wallichiana, mixed coniferous, Abies pindrow (AP) and Betula utilis (BU)] of Kashmir Himalaya. A total of 177 plant species (158 genera, 66 families) were recorded. Most of the species are herbs (82.5%), while shrubs account for 9.6% and trees represent 7.9%. Species richness ranged from 24 (PD) to 96 (AP). Shannon, Simpson, and Fisher α indices varied: 0.17–1.06, 0.46–1.22, and 2.01–2.82 for trees; 0.36–0.94, 0.43–0.75, and 0.08–0.35 for shrubs; and 0.35–1.41, 0.27–0.95, and 5.61–39.98 for herbs, respectively. A total of five species were endemic. The total stems and basal area of trees were 35,794 stems (stand mean 330 stems/ha) and 481.1 m2 (stand mean 40.2 m2/ha), respectively. The mean density and basal area ranged from 103 stems/ha (BU) to 1,201 stems/ha (PD), and from 19.4 m2/ha (BU) to 51.9 m2/ha (AP), respectively. Tree density decreased with increase in diameter class. A positive relationship was obtained between elevation and species richness and between elevation and evenness (R2 = 0.37 and 0.19, respectively). Tree and shrub communities were homogenous in nature across the seven forest types, while herbs showed heterogeneous distribution pattern

ANTIOXIDATIVE AND ANTIBACTERIAL POTENTIALS OF FUNGAL ENDOPHYTES FROM JUSTICIA WYNAADENSIS HEYNE: AN ETHNOMEDICINAL RAIN FOREST SPECIES OF WESTERN GHATS

Objective: Endophytes, living within the medicinal plants, are recognized as an alternative source of bioactive components useful for human health. This study aims to isolate and identify the fungal endophytes from the ethnomedicinal rain forest plant Justicia wynaadensis and evaluation of their antioxidant and antimicrobial potentials. Methods: Endophytic fungi were isolated and identified by sequencing the internal transcribed spacer. The secondary metabolites were extracted with ethyl acetate and evaluated for the total phenolic, flavonoid, antioxidant, and antibacterial potentials. The antioxidative capacities were determined using different experimental models, viz., radical scavenging capacity, reducing power, and inhibition of lipid peroxidation. The antibacterial potential of extracts was determined through disc diffusion method and by evaluating minimum inhibitory concentration through microplate technique. Results: A total of nine fungal endophytes belonging to six genera were identified. The total phenolic content of the extracts ranged from 4.8±0.08 to 20.74±0.96 mg Gallic acid equivalent/g dry extract. Flavonoid was present in eight extracts in the range of 2.1±0.08 to 8.75±0.6 mg catechin equivalent/g dry extract. Fusarium incarnatum was found to have potentially high antioxidant capacity as well as broad spectrum antibacterial activity against Gram-positive and Gram-negative bacteria. Conclusion: This study reported various endophytic fungi from the plant J. wynaadensis. This is the first attempt to explore the treasure of endophytes and their bioactive potentiality from this plant. Hence, our findings encourage the exploration of these fungi and exploit them in search of potential drug discovery

Suppression of eukaryotic initiation factor 4E prevents chemotherapy-induced alopecia

BACKGROUND: Chemotherapy-induced hair loss (alopecia) (CIA) is one of the most feared side effects of chemotherapy among cancer patients. There is currently no pharmacological approach to minimize CIA, although one strategy that has been proposed involves protecting normal cells from chemotherapy by transiently inducing cell cycle arrest. Proof-of-concept for this approach, known as cyclotherapy, has been demonstrated in cell culture settings. METHODS: The eukaryotic initiation factor (eIF) 4E is a cap binding protein that stimulates ribosome recruitment to mRNA templates during the initiation phase of translation. Suppression of eIF4E is known to induce cell cycle arrest. Using a novel inducible and reversible transgenic mouse model that enables RNAi-mediated suppression of eIF4E in vivo, we assessed the consequences of temporal eIF4E suppression on CIA. RESULTS: Our results demonstrate that transient inhibition of eIF4E protects against cyclophosphamide-induced alopecia at the organismal level. At the cellular level, this protection is associated with an accumulation of cells in G1, reduced apoptotic indices, and was phenocopied using small molecule inhibitors targeting the process of translation initiation. CONCLUSIONS: Our data provide a rationale for exploring suppression of translation initiation as an approach to prevent or minimize cyclophosphamide-induced alopecia.1U01 CA168409 - NCI NIH HHS; P01 CA 87497 - NCI NIH HHS; P30 CA008748 - NCI NIH HHS; MOP-106530 - Canadian Institutes of Health Research; P01 CA013106 - NCI NIH HH

Acceleration-based Kalman tracking for super-resolution ultrasound imaging in vivo

Super-resolution ultrasound can image microvascular structure and flow at sub-wave-diffraction resolution based on localising and tracking microbubbles. Currently, tracking microbubbles accurately under limited imaging frame rates and high microbubble concentrations remains a challenge, especially under the effect of cardiac pulsatility and in highly curved vessels. In this study, an acceleration-incorporated microbubble motion model is introduced into a Kalman tracking framework. The tracking performance was evaluated using simulated microvasculature with different microbubble motion parameters, concentrations and acquisition frame rates, and in vivo human breast tumour ultrasound datasets. The simulation results show that the acceleration-based method outperformed the non-acceleration-based method at different levels of acceleration and acquisition frame rates and achieved significant improvement in true positive rate (up to 11.3%), false negative rate (up to 13.2%). The proposed method can also reduce errors in vasculature reconstruction via the acceleration-based nonlinear interpolation, compared with linear interpolation (up to 16.7 μm). The tracking results from temporally downsampled low frame rate in vivo datasets from human breast tumours show that the proposed method has better microbubble tracking performance than the baseline method, if using results from the initial high frame data as reference. Finally, the acceleration estimated from tracking results also provides a spatial speed gradient map that may contain extra valuable diagnostic information

Assessment of tree diversity in distinctive deciduous forests of Suruli falls, Southern Western Ghats

A quantitative inventory was conducted in two distinctive tropical deciduous forests at Suruli falls forest of southern Western Ghats.  Two one-hectare plots were established and all trees >10cm DBH measured. Species richness, density, family importance value (FIV) and importance value index (IVI) were calculated and the results varied among the two sites. A total of 777 stems and 52 species were documented in both the sites and moist deciduous forest (MDF) had maximum number species richness and density than dry deciduous forest (DDF). The basal area was higher in MDF (502 stems/ha and 16.52 m2/ha) than in DDF (275 stems/ha and 7.23 m2/ha). However, Shannon and evenness indices showed a negative trend (DDF- 2.62, 0.41 and MDF- 2.37, 0.27). Diameter class-wise distribution of trees showed reverse ‘J shaped’ curve in both the forest types. Pterocarpus marsupium was the mono-dominant species holding one-third of the IVI (113), 27% of the stem density and 30% of the total basal area. DDF site is suspected to recurrence of annual fire. Anogeissus latifolia and Strychnos potatorum were the fire-tolerant species only found in lower diameter class. The maximum species shared contiguous distribution in the deciduous forests. The observed variations in the tree community between the two deciduous forest sites are possibly due to variations in altitude, rainfall, temperature, past disturbance, fire and edaphic characteristics