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This study aimed to examine attachment and adult separation anxiety (ASA) among women who lost a parent in their youth. We hypothesized that insecure attachment and increased ASA from a romantic partner would be found among women who have lost a parent in youth, compared to women whose parents were both alive. Sixty women who lost one or both parents in their youth and 60 who had living parents participated in the study (mean age: 32.3, range: 18-62 years). Participants filled out the ASA and Short Attachment questionnaires. Women who lost a parent reported higher levels of anxious attachment and ASA from partner; the two groups did not differ, however, in terms of avoidant attachment. Additionally, similar effects on ASA and attachment were found among adult women who lost a father or a mother in their youth. In conclusion, the loss of a parent early in life may be associated with an insecure attachment style and increased ASA.
Asunto(s)
Ansiedad de Separación , Apego a Objetos , Humanos , Femenino , Adulto , Ansiedad de Separación/psicología , Adolescente , Adulto Joven , Persona de Mediana Edad , Divorcio/psicología , Encuestas y Cuestionarios , Padres/psicologíaRESUMEN
The density functional theory method was employed to calculate three-dimensional structures for a series of novel explosophores. The design of new molecules (DA1-DA12) was based on the bridge-ring structures that could be formed via Diels-Alder (DA) reaction of selected nitrogen-rich dienes and tetranitroethylene dienophile. The feasibility of the proposed DA reactions was predicted on the basis of the molecular orbital theory. The strong interactions between the HOMO of dienes, with electron-donating groups (Diene2, Diene6, and Diene8), and the LUMO of tetranitroethylene dienophile suggested thermodynamically favorable formation of the desired DA reaction products. In addition to molecular structures of the explored DA compounds, their physicochemical and energetic properties were also calculated in detail. Due to compact bridge-ring structures, new energetic molecules have highly positive heats of formation (up to 1124.90 kJ·mol-1) and high densities (up to 2.04 g·cm-3). Also, as a result of all-right ratios of nitrogen and oxygen, most of the new compounds possess high detonation velocities (8.28-10.02 km·s-1) and high detonation pressures (30.87-47.83 GPa). Energetic compounds DA1, DA4, and DA12 exhibit a superior detonation performance over widely used HMX explosive, and DA5, DA7, and DA10 could be comparable to the state-of-the-art CL-20 and ONC explosives. Our proposed designs and synthetic methodology should provide a platform for the development of novel energetic materials with superior performance.
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A series of novel highly thermostable energetic coordination polymers (ECPs), with promising mechanical sensitivity properties, were prepared by an in situ oxidation-coordination reaction of triaminoguanidine hydrochloride with copper nitrate in aqueous solution. The molecular structures and properties of these ECPs could be tuned, by varying the ratios and concentrations of the starting materials. Our ECPs exhibit remarkable thermostability (>390 °C) and very low sensitivity to impact (Im > 98 J). The best-performing material (ECP-5) has a calculated detonation velocity of 8969 m·s(-1) and a decomposition peak temperature of 396.9 °C, demonstrating an outstanding balance between two inherently contradicting properties: high detonation performance and very low sensitivity.
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In recent years, research in the field of carbon nanomaterials (CNMs), such as fullerenes, expanded graphite (EG), carbon nanotubes (CNTs), graphene, and graphene oxide (GO), has been widely used in energy storage, electronics, catalysts, and biomaterials, as well as medical applications. Regarding energy storage, one of the most important research directions is the development of CNMs as carriers of energetic components by coating or encapsulation, thus forming safer advanced nanostructures with better performances. Moreover, some CNMs can also be functionalized to become energetic additives. This review article covers updated preparation methods for the aforementioned CNMs, with a more specific orientation towards the use of these nanomaterials in energetic compositions. The effects of these functionalized CNMs on thermal decomposition, ignition, combustion and the reactivity properties of energetic compositions are significant and are discussed in detail. It has been shown that the use of functionalized CNMs in energetic compositions greatly improves their combustion performances, thermal stability and sensitivity. In particular, functionalized fullerenes, CNTs and GO are the most appropriate candidate components in nanothermites, solid propellants and gas generators, due to their superior catalytic properties as well as facile preparation methods.
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We previously demonstrated that anti-third-party CTLs (stimulated under IL-2 deprivation against cells with an MHC class I [MHC-I] background different from that of the host and the donor) are depleted of graft-versus-host reactivity and can eradicate B cell chronic lymphocytic leukemia cells in vitro or in an HU/SCID mouse model. We demonstrated in the current study that human allogeneic or autologous anti-third-party CTLs can also efficiently eradicate primary non-Hodgkin B cell lymphoma by inducing slow apoptosis of the pathological cells. Using MHC-I mutant cell line as target cells, which are unrecognizable by the CTL TCR, we demonstrated directly that this killing is TCR independent. Strikingly, this unique TCR-independent killing is induced through lymphoma MHC-I engagement. We further showed that this killing mechanism begins with durable conjugate formation between the CTLs and the tumor cells, through rapid binding of tumor ICAM-1 to the CTL LFA-1 molecule. This conjugation is followed by a slower second step of MHC-I-dependent apoptosis, requiring the binding of the MHC-I α2/3 C region on tumor cells to the CTL CD8 molecule for killing to ensue. By comparing CTL-mediated killing of Daudi lymphoma cells (lacking surface MHC-I expression) to Daudi cells with reconstituted surface MHC-I, we demonstrated directly for the first time to our knowledge, in vitro and in vivo, a novel role for MHC-I in the induction of lymphoma cell apoptosis by CTLs. Additionally, by using different knockout and transgenic strains, we further showed that mouse anti-third-party CTLs also kill lymphoma cells using similar unique TCR-independence mechanism as human CTLs, while sparing normal naive B cells.
Asunto(s)
Apoptosis/inmunología , Antígenos CD8/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunidad Celular , Linfoma de Células B/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Apoptosis/genética , Linfocitos B/inmunología , Linfocitos B/patología , Antígenos CD8/genética , Línea Celular Tumoral , Femenino , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Molécula 1 de Adhesión Intercelular/genética , Molécula 1 de Adhesión Intercelular/inmunología , Antígeno-1 Asociado a Función de Linfocito/genética , Antígeno-1 Asociado a Función de Linfocito/inmunología , Linfoma de Células B/genética , Linfoma de Células B/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ratones SCID , Mutación , Linfocitos T Citotóxicos/patologíaRESUMEN
TV-5010 is a higher molecular weight version of glatiramer acetate (GA), the active ingredient of Copaxone - an approved drug for the treatment of multiple sclerosis (MS). GA has been shown to ameliorate colitis in several experimental models when administered by daily injection. The present study aimed to explore the effect of TV-5010 in a murine model of inflammatory bowel disease (IBD) and the possibility for its administration in tapered frequency. As demonstrated here, TV-5010 ameliorated the various pathological manifestations of Dextran (DSS)-induced colitis, i.e. weight loss, intestinal bleeding and diarrhea, resulting in substantial reduction of disease activity, colonic damage and mortality. In contrast to GA, which was more effective when administered daily by injection of 2.0 mg/mouse, TV-5010 was most effective when administered once a week, at dose of 0.2-1.0 mg/mouse. TV-5010 treatment abrogated the characteristic inflammation in the diseased organ as demonstrated by reduction in the colonic mRNA expression of TNF-alpha, IFN-gamma and the Th1 transcription factor T-bet, as well as by augmentation of the regulatory cytokine TGF-beta. Injection of naive mice with TV-5010 generated lymphocyte population of the Th2/3 subtype that effectively reduced disease manifestations upon adoptive transfer to mice with DSS-colitis. Moreover, TV-5010-specific T-cells, either exogenously labeled or genetically marked, adoptively transferred to colitis-induced mice, localized in the inner layers of the injured colon and expressed TGF-beta in situ. Thus, TV-5010 is effective in the suppression of experimental colitis similarly to GA, with the advantage of less frequent administration, possibly via immunomodulation at the site of pathological damage.