Adapting Load Limiter Deployment for Frontal Crash Diversity

Objective: Current European restraint systems may not realize their full protection potential in real-world frontal crashes because they are highly optimized for specific conditions. This research sought to quantify the potential benefit of adapting seat belt load limit thresholds to a wider range of occupant and crash characteristics.Methods: Numerical simulations using Hybrid III dummies were conducted to determine how varying load limiter thresholds could affect occupant kinematics and injury outcome in frontal impacts. Occupant–compartment models were developed with a restraint system consisting of a frontal airbag and a 3-point belt with retractor, buckle pretensioner, and load limiting at the shoulder. Load limiting threshold was varied in 5 frontal impact scenarios, covering as wide a range of real frontal crash conditions as possible. The simulated thoracic injury risks were converted into injury probability values using Abbreviated Injury Scale (AIS) 2+ age-dependent thoracic risk curves. These values were then applied to a British real-world frontal impact sample to determine the injury reduction potential of optimized load limiting, taking into account occupant seating position, impact scenario, occupant size, and occupant age and assuming that an appropriate adaptive system was fitted to all cars.Results: In low-severity impacts, a low load limit provided the best chest protection, without increasing risk to other body regions, for both the 50th and 95th percentile dummies in both front seating positions. In high-severity impacts, the low limit was not recommended because it allowed the driver dummy to move into close proximity with the vehicle interior, although there appeared to be some benefit of lower load limiting for the 50th percentile front passenger dummy, due to the increased ride down space in that seating position. Adapting the load limit showed no injury reduction potential for 5th percentile drivers. Utilizing the best load limit threshold in real-world crashes could reduce the number of occupants with AIS 2+ chest injuries from belt loading from 377 to 251 (a 33% reduction), correspondingly reducing the number of occupants with AIS 2+ chest injuries (from all sources) in the whole frontal impact population from 496 to 370. This is a reduction in injury rate from 6.4% to 4.8%.Conclusions: The concept of an adaptive load limiter shows most promise in low-speed frontal crashes where it could lower the AIS 2+ chest injury risk for most front seat occupants, except the smallest of drivers. Generally, adaptive limiters show less potential effectiveness with increased crash severities. Overall, an intelligent adjustment of load limiting threshold could result in a reduction of at least a third of front seat occupants with AIS 2+ chest injuries associated with restraining loads and an overall reduction in AIS 2+ chest injury rate in frontal crashes from 6.4% to 4.8%</div

Factors associated with chest injuries to front seat occupants in frontal impacts

Objective: Improving crash protection for older car occupants is a matter of urgency since the number of older car users is forecast to grow dramatically over the next two decades. The thorax is particularly vulnerable in older occupants, and this study aimed to provide real-world in-depth analysis of factors contributing to chest injuries in frontal impacts involving European cars. Methods: Real world crash injury data were interrogated, focusing on cars with current restraint components. The research examined belted front-seat occupants in frontal impacts where air bags, pretensioners and load limiters were present. Results: The chest was the most often injured body region at AIS 2+, 3+ and 4+ injury levels. The rate of AIS 2+ and AIS 3+ chest injuries was highest among elderly occupants and lowest among young occupants, and elderly occupants sustained proportionally more severe chest injuries in low/moderate speed impacts compared to young and middle-aged occupants. However, it should be noted that rates of AIS 2 chest injury were also significantly higher for middle-aged occupants compared to the young. The front passenger seat was shown to be more often associated with significant chest injury than the driver seat. The higher proportion of elderly female occupants was postulated as a reason for this. Skeletal injury was the most frequent type of AIS 2+ chest injury and the rate of injury for elderly occupants with such injuries was higher than for young and middle-aged occupants. With the increase in the number of rib fractures, the risk of pulmonary complications and organ injuries tended to increase. The major cause of chest injury was identified as restraining loads transmitted to the chest via the seat belt. The absence of intrusion in the majority of cases, suggests an opportunity for the restraint system to better manage the crash pulse. Not only for elderly occupants but for those who are middle-aged as well. Conclusions: This study shows the necessity for safety interventions, through new vehicle crashworthiness systems to improve chest protection especially for middle aged and elderly car occupants. Deployment of appropriate injury risk criteria, use of an appropriate dummy thorax, development of a low energy restraint test, and the development of more adaptive restraints have been discussed as possible solutions to the problem

Synthesis and down conversion emission property of Eu3+ doped LaAlO3 CsAlO2 and LiLaO2 phosphors

[EN] LaAlO3:Eu3+, CsAlO2:Eu3+ and LiLaO2:Eu3+ phosphors with varying concen- trations of Eu3+ from 3 to 10 mol% were prepared by combustion synthesis method and the samples were further heated to 1,000ºC to improve the crystallinity of the materials. The structure and morphology of materials have been examined by X-ray diffraction and scan- ning electron microscopy. SEM images depicted that the morphology of crystallites have no uniform shapes and sizes. Small and coagulated particles of irregular shapes of different sizes are obtained. The characteristic emissions of Eu3+ were clearly observed at nearly 580, 592, 650, 682 to 709 (multiplet structure) nm for 5D - 7 Fn transitions where n = 0, 1, 3, 4 respectively, including the strongest emission peaks at 614 and 620 nm for 5 D0 - 7 F2 transitions in CsAlO2:Eu3+ and LiLaO2:Eu3+ host lattices. The intensity of emission peak corresponding to 5 D0 !&#8594; 7 F1 transitions in LaAlO3 :Eu3+ material is comparable to that of 5D0 5D-7F2 transitions which is also a singlet. Photoluminescence intensity follows the order as in LiLaO2 > LaAlO3 > CsAlO2 lattices. Remarkable high photoluminescence intensity with 7 mol% doping of Eu3+ in LiLaO2 makes it a strong contender for red colored display applications.This work was supported by the European Commission through Nano CIS project (FP7-PEOPLE-2010-IRSES ref. 269279).Marí Soucase, B.; Singh, KC.; Moya Forero, MM.; Singh, I.; Om, H.; Chand, S. (2015). Synthesis and down conversion emission property of Eu3+ doped LaAlO3 CsAlO2 and LiLaO2 phosphors. Optical and Quantum Electronics. 47(7):1569-1578. https://doi.org/10.1007/s11082-014-9997-9S15691578477Abbattista, F., Vallino, M.: Remarks on the $$\text{La}_{2}\text{O}_{3}-\text{Li}_{2}\text{O}$$ La 2 O 3 - Li 2 O binary system between 750 and 1,000  $$^{\circ}$$ ∘ C. Ceram. Int. 9, 35–38 (1983)Bae, Y., Lee, K., Byeon, S.: Synthesis and $$\text{Eu}^{3+}$$ Eu 3 + concentration-dependent photoluminescence of $$\text{Gd}_{\rm 2-x}\text{Eu}_{\rm x}\text{O}_{3}$$ Gd 2 - x Eu x O 3 nanowires. J. Lumin. 129, 81–85 (2009)Blasse, G., Grambier, B.: Luminescent Materials, vol. 43. Springer, Berlin, pp. 43–46 (1994)Dereń, P., Krupa, J.: Spectroscopic investigations of $$\text{LaAlO}_{3}$$ LaAlO 3 : $$\text{Eu}^{3+}$$ Eu 3 + . J. Lumin. 102–103, 386–390 (2003)Ekambaram, S., Patil, K.: Synthesis and properties of $$\text{Eu}^{2+}$$ Eu 2 + activated blue phosphors. J. Alloys Compd. 248, 7–12 (1997)Gao, X., Lei, L., Lv, C., Sun, Y., Zheng, H., Cui, Y.: Preparation and photoluminescence property of a loose powder, $$\text{Ca}_{3}\text{Al}_{2}\text{O}_{6}$$ Ca 3 Al 2 O 6 : $$\text{Eu}^{3+}$$ Eu 3 + by calcination of a layered double hydroxide precursor. J. Solid State Chem. 181, 1776–1781 (2008)Hayakawa, T., Kamt, N., Yamada, K.: Visible emission characteristics in $$\text{Tb}^{3+}$$ Tb 3 + -doped fluorescent glasses under selective excitation. J. Lumin. 68, 179–186 (1996)Hreniak, D., Strek, W., Dereń, P., Bednarkiewicz, A., Łukowiak, A.: J. Alloys Compd. 408, 828–830 (2006)Huang, Y., Jiang, C., Cao, Y., Shi, L., Seo, H.: Luminescence and microstructures of $$\text{Eu}^{3+}$$ Eu 3 + -doped in triple phosphate $$\text{Ca}_{8}\text{MgR}(\text{PO}_{4})_{7}$$ Ca 8 MgR ( PO 4 ) 7 (R = La, Gd, Y) with whitlockite structure. Mater. Res. Bull. 44, 793–798 (2009)Kharbache, H., Mahiou, R., Boutinaud, P., Boyer, D., Zakaria, D., Deren, P.: Experimental evidence of $$\text{Eu}^{3+}$$ Eu 3 + pairs in $$\text{K}_{2}\text{EuF}_{5}$$ K 2 EuF 5 . Opt. Mater. 31, 558–561 (2009)Kijima, T., Shinbori, T., Sekita, M., Uota, M., Sakai, G.: Abnormally enhanced $$\text{Eu}^{3+}$$ Eu 3 + emission in $$\text{Y}_{2}\text{O}_{2}\text{SO}_{4}$$ Y 2 O 2 SO 4 : $$\text{Eu}^{3+}$$ Eu 3 + inherited from their precursory dodecylsulfate-templated concentric-layered nanostructure. J. Lumin. 128, 311–316 (2008)Liu, G., Hong, G., Wang, J., Dong, X.: Hydrothermal synthesis of spherical and hollow $$\text{Gd}_{2}\text{O}_{3}$$ Gd 2 O 3 : $$\text{Eu}^{3+}$$ Eu 3 + phosphors. J. Alloys Compd. 432, 200–204 (2007)Mączka, M., Bednarkiewicz, A., Mendoza-Mendoza, E., Fuentes, A.F., Kępiński, L.: Optical properties of Eu and Er doped $$\text{LaAlO}_{3}$$ LaAlO 3 nanopowders prepared by low-temperature method. J. Solid State Chem. 194, 264–269 (2012)Mao, Z., Wang, D., Lu, Q., Yu, W., Yuan, Z.: Tunable single-doped single-host full-color-emitting $$\text{LaAlO}_{3}$$ LaAlO 3 : $$\text{Eu}$$ Eu phosphor via valence state-controlled means. Chem. Commun. 3, 346–348 (2009)Mao, Z.Y., Wang, D.J., Liu, Y.H., Fei, Q.N., Zheng, X., Xu, S.C., Qiu, K.: Tuning the color purity of $$\text{LaAlO}_{3}$$ LaAlO 3 : $$\text{Eu}^{3+}$$ Eu 3 + red phosphor by the cross relaxation. Opto Electron. Lett. 6, 116–119 (2010)Marí, B., Singh, K., Sahal, M., Khatkar, S., Taxak, V., Kumar, M.: Preparation and luminescence properties of $$\text{Tb}^{3+}$$ Tb 3 + doped $$\text{ZrO}_{2}$$ ZrO 2 and $$\text{BaZrO}_{3}$$ BaZrO 3 phosphors. J. Lumin. 130, 2128–2132 (2010)Marí, B., Singh, K.C., Cembrero-Coca, P., Singh, I., Singh, D., Chand, S.: Red emitting $$\text{MTiO}_{3}$$ MTiO 3 (M = Ca & Sr) phosphor doped with $$\text{Eu}^{+3}$$ Eu + 3 or $$\text{Pr}^{+3}$$ Pr + 3 with some cations as co-dopands. Displays 34, 346–351 (2013)Ningthoujam, R., Sudarsan, V., Kulshreshtha, S.: $$\text{SnO}_{2}$$ SnO 2 : $$\text{Eu}$$ Eu nanoparticles dispersed in silica: A low-temperature synthesis and photoluminescence study. J. Lumin. 127, 747–756 (2007)Ogasawara, K., Watanabe, S., Toyoshima, H., Brik, M.G.: Handbook on Physics and Chemistry of Rare Earths, vol. 1. Elsevier, Amsterdam (2007)Pereyra-Perea, E., Estrada-Yañez, M.R., García, M.: Preliminary studies on luminescent terbium-doped ZrO2 thin films prepared by the sol-gel process. J. Phys. D 31, 7–10 (1998)Perez, D., Vegas, A.: The Zintl-Klemm concept applied to cations in oxides. I. The structures of ternary aluminates. Acta Cryst. B 59, 305–323 (2003)Pieterson, L., Heeroma, M., Heer, E., Meijerink, A.: Charge transfer luminescence of $$\text{Yb}^{3+}$$ Yb 3 + . J. Lumin. 91, 177–193 (2000)Shi, C., Shi, J., Deng, J., Han, Z., Zhou, Y., Zhang, G.: Excitation states of $$\text{RE}^{3+}$$ RE 3 + -pentaphosphates in VUV and UV range. J. Electron. Spectros. Relat. Phenomena 79, 121–124 (1996)Singh, V., Watanabe, S., Gundu Rao, T.K., Chubaci, J.F.D., Kwak, H.-Y.: Characterization, photoluminescence, thermally stimulated luminescence and electron spin resonance studies of $$\text{Eu}^{3+}$$ Eu 3 + doped $$\text{LaAlO}_{3}$$ LaAlO 3 phosphor. Solid State Sci. 13, 66–71 (2011)Solovyev, O.V., Malkin, B.Z.: Modeling of electron-vibrational $$4\text{f}^{\rm n}-4\text{f}^{{\rm n}-1}5\text{d}$$ 4 f n - 4 f n - 1 5 d spectra in $$\text{LiYF}_{4}$$ LiYF 4 : $$\text{RE}^{3+}$$ RE 3 + crystals. J. Mol. Struct. 838, 176–181 (2007)Zhang, Y., Li, W., Jingjun, X.: Structure and photoluminescence properties of $$\text{KSr}_{4}(\text{BO}_{3})_{3}$$ KSr 4 ( BO 3 ) 3 : $$\text{Eu}^{3+}$$ Eu 3 + red-emitting phosphor. Opt. Mater. Express 2(2012), 92–102 (2012)Zhou, L., Yan, B.: Sol-gel synthesis and photoluminescence of $$\text{CaSiO}_{3}$$ CaSiO 3 : $$\text{Eu}^{3+}$$ Eu 3 + nanophosphors using novel silicate sources. J. Phys. Chem. Solids 69, 2877–2882 (2008

In vitro anti-HIV activity of some Indian medicinal plant extracts

Background Human Immunodeficiency Virus (HIV) persists to be a significant public health issue worldwide. The current strategy for the treatment of HIV infection, Highly Active Antiretroviral Therapy (HAART), has reduced deaths from AIDS related disease, but it can be an expensive regime for the underdeveloped and developing countries where the supply of drugs is scarce and often not well tolerated, especially in persons undergoing long term treatment. The present therapy also has limitations of development of multidrug resistance, thus there is a need for the discovery of novel anti-HIV compounds from plants as a potential alternative in combating HIV disease. Methods Ten Indian medicinal plants were tested for entry and replication inhibition against laboratory adapted strains HIV-1IIIB, HIV-1Ada5 and primary isolates HIV-1UG070, HIV-1VB59 in TZM-bl cell lines and primary isolates HIV-1UG070, HIV-1VB59 in PM1 cell lines. The plant extracts were further evaluated for toxicity in HEC-1A epithelial cell lines by transwell epithelial model. Results The methanolic extracts of Achyranthes aspera, Rosa centifolia and aqueous extract of Ficus benghalensis inhibited laboratory adapted HIV-1 strains (IC80 3.6–118 μg/ml) and primary isolates (IC80 4.8–156 μg/ml) in TZM-bl cells. Methanolic extract of Strychnos potatorum, aqueous extract of Ficus infectoria and hydroalcoholic extract of Annona squamosa inhibited laboratory adapted HIV-1 strains (IC80 4.24–125 μg/ml) and primary isolates (IC80 18–156 μg/ml) in TZM-bl cells. Methanolic extracts of Achyranthes aspera and Rosa centifolia, (IC801-9 μg/ml) further significantly inhibited HIV-1 primary isolates in PM1cells. Methanolic extracts of Tridax procumbens, Mallotus philippinensis, Annona reticulate, aqueous extract of Ficus benghalensis and hydroalcoholic extract of Albizzia lebbeck did not exhibit anti-HIV activity in all the tested strains. Methanolic extract of Rosa centifolia also demonstrated to be non-toxic to HEC-1A epithelial cells and maintained epithelial integrity (at 500 μg/ml) when tested in transwell dual-chamber. Conclusion These active methanolic extracts of Achyranthes aspera and Rosa centifolia, could be further subjected to chemical analysis to investigate the active moiety responsible for the anti-HIV activity. Methanolic extract of Rosa centifolia was found to be well tolerated maintaining the epithelial integrity of HEC-1A cells in vitro and thus has potential for investigating it further as candidate microbicide

Civil society leadership in the struggle for AIDS treatment in South Africa and Uganda

Includes abstract.Includes bibliographical references.This thesis is an attempt to theorise and operationalise empirically the notion of ‘civil society leadership’ in Sub-Saharan Africa. ‘AIDS leadership,’ which is associated with the intergovernmental institutions charged with coordinating the global response to HIV/AIDS, is both under-theorised and highly context-specific. In this study I therefore opt for an inclusive framework that draws on a range of approaches, including the literature on ‘leadership’, institutions, social movements and the ‘network’ perspective on civil society mobilisation. This framework is employed in rich and detailed empirical descriptions (‘thick description’) of civil society mobilisation around AIDS, including contentious AIDS activism, in the key case studies of South Africa and Uganda. South Africa and Uganda are widely considered key examples of poor and good leadership (from national political leaders) respectively, while the Treatment Action Campaign (TAC) and The AIDS Support Organisation (TASO) are both seen as highly effective civil society movements. These descriptions emphasise ‘transnational networks of influence’ in which civil society leaders participated (and at times actively constructed) in order to mobilise both symbolic and material resources aimed at exerting influence at the transnational, national and local levels