369 research outputs found
Ecological basis of coevolutionary history
Journal ArticleMacroevolutionary patterns are difficult to interpret because they are the product of a time scale so vast that deterministic and chance events are hard to distinguish. Although the macroevolutionary history of a group can be reconstructed from extant species, determining the ecological context in which that group evolved is a tall order. Ecology involves interactions between organisms and both the living and nonliving components of their environments
Antioxidant, antimicrobial, and theoretical studies of the thiosemicarbazone derivative Schiff base 2-(2-imino-1-methylimidazolidin-4-ylidene)hydrazinecarbothioamide (IMHC)
Fullerenes and Nanodiamonds for Medical Drug Delivery
Carbon is a chemical element has the ability of forming long carbonic chain. Due to its special electronic structure, each carbon atom can be linked with another carbon atom or with another element via single, double or triple covalent bonds. The special electronic structure of carbon atom affecting on its properties also affecting on its ability of existing in different forms called allotropes. During few last decades, new carbon-based nanomaterials have been described including fullerene, carbon nanotube, graphene and nanodiamond. These new allotropes attracted the interest of science and industry and became as a new and important class of materials due to its outstanding features which candidate for numerous applications. In parallel with new developments in nanomedicine especially in drug delivery field, the targeted delivery systems became an important to overcome the limitations of the old fashion systems. So, it become very important to translate this idea into reality. Fullerene and nanodiamond have a unique combination of structure, morphology and biological properties that make them as a powerful tools for targeted delivery system. So, this chapter will focus on two major aspects: synthesis routes of fullerenes and nanodiamonds, and their role in nanomedicine as drug delivery systems
A state-of-the-art review of energy-efficient and renewable energy systems in higher education facilities
Amid escalating energy demands and growing environmental concerns, educational institutions are transforming into crucibles for enduring innovation. This comprehensive review summarizes the complex relationship between Energy Efficiency and Renewable Energy Systems (EERES) within the sphere of educational institutions. By instituting Energy Efficiency initiatives, organizations can curtail energy consumption, resulting in substantial cost savings and a diminished carbon footprint. Moreover, the integration of renewable energy technologies empowers the localized generation of electricity, ensuring a reliable and sustainable energy source. Noteworthy in this study is the novel linkage of energy usage indicators to the comfort levels experienced in university settings during both summer and winter. An exhaustive examination of consumption indicators, rooted in the diverse activities on college campuses, further enriches the investigation. Beyond technical intricacies, this study scrutinizes the economic viability, environmental advantages, and educational significance of these integrated systems. Embracing EERES not only aligns with the commitment of educational institutions to environmental stewardship but also establishes a paradigm for broader communities. These institutions aspire to exemplify sustainable practices, influencing larger societal behavior positively. Various factors, including the institution’s type, energy source, facility nature, building construction, internal activities, weather conditions, and user behavior, wield substantial influence over energy utilization. This study offers a nuanced exploration, shedding light not only on the technical dimensions but also on the broader economic, environmental, and educational implications of adopting EERES
A Comparison Study in the Management of Ectopic Pregnancy between State of Qatar and Kingdom of Bahrain
Ectopic pregnancy is of increasing concern to gynecologists since it is a major cause of maternal mortality and morbidity in reproductive age women. It occurs when the conceptus implants in an abnormal position other than the uterus. Although the incidence of ectopic pregnancy during the 20 years studied increased five-folds, the risk of death from ectopic pregnancy declined by 90%. This decline might be related to the increase awareness of this condition that accompanied improved diagnostic technology and thus improved management and care. However, ectopic pregnancy remains the leading cause of maternal mortality in first trimenster. This study was to evaluate the management of ectopic pregnancy in the State of Qatar and the Kingdom of Bahrain in a time period from January I, 2000 to August 31, 2003. Statistical analysis showed high incidence of ectopic pregnancy with increase in age and abortion. Etiological factors including contraceptive usage, infertility treatment and previous ectopic pregnancy were shown to increases ectopic pregnancy rates. In the Kingdom of Bahrain, management of ectopic pregnancy was carried by surgical salpingectomy and Laparoctomy and to a lesser extend medical Methotrexate management was also carried on. While in the State of Qatar it was the opposite as Methotrexate was mainly used rather than the surgical treatment. It is recommended that further investigations are needed to enhance this data and to prove the benefits of medical management over the surgical management.qscienc
2-{[5-(Adamantan-1-yl)-4-methyl-4H-1,2,4-triazol-3-yl]sulfanyl}-N,N-dimethylethanamine
In the title compound, C17H28N4S, the 1,2,4-triazole ring is nearly planar [maximum deviation = 0.005 (2) Å]. There are no significant hydrogen bonds observed in the crystal structure. The crystal studied was a non-merohedral twin, the refined ratio of twin components being 0.281 (3):0.719 (3)
Culpability, blame, and stigma after pregnancy loss in Qatar
Background: Following a miscarriage many women report feeling guilty and culpable for what has happened
particularly when aspects of societal blame and stigma are involved. This research investigated the impact of
cultural context on the experience of miscarriage. In particular, it focused on how elements of stigma and blame
are linked to notions of miscarriage etiology and risk among Qatari women.
Methods: The research used an ethnographic approach. The data was collected over 18 months of fieldwork in
Qatar, using semi-structured face to face interviews, and participant observation. A purposive sample of 40 women
(primary participants) who had recently miscarried, participated in the study. Potential subjects were initially
identified in the Women’s Hospital and were consented, and then interviewed in Arabic either in the hospital or at
their preferred location. The interviews were audio recorded, transcribed and translated into English. Additional key
interviews were performed with 20 secondary participants related to the miscarriage cohort including family
members and husbands. Inductive thematic analysis of content was performed manually to extract themes.
Results: Two main themes emerged from the material looking specifically at miscarriage aftermaths: rhetorics of
blame, self-blame and feelings of guilt; and miscarriage attitudes. Overall society is sympathetic and miscarriage is
seen as normal and not particularly worrying, but understood to be upsetting to women. However, findings
suggest there is some ambivalence around blame, culpability and stigma applied to miscarriage; some participants
perceived miscarriage as a relatively normal and common event, whereas, others felt that miscarriage is resounding
stigma and shame.
Conclusion: Miscarriage aftermaths are embedded in social, cultural and religious frameworks in relation to notions
of risk and causation. Attention should be paid to ensure women and those around them are given appropriate
and robust information about miscarriage causation to deflect discourses of blame that may be employed and
reduce harm to women who suffer miscarriage
Optimization of a Patient-Specific External Fixation Device for Lower Limb Injuries
From MDPI via Jisc Publications RouterHistory: accepted 2021-08-02, pub-electronic 2021-08-10Publication status: PublishedFunder: Engineering and Physical Sciences Research Council; Grant(s): EP/R01513/1Funder: King Saud University; Grant(s): RSP-2021/299The use of external fixation devices is considered a valuable approach for the treatment of bone fractures, providing proper alignment to fractured fragments and maintaining fracture stability during the healing process. The need for external fixation devices has increased due to an aging population and increased trauma incidents. The design and fabrication of external fixations are major challenges since the shape and size of the defect vary, as well as the geometry of the human limb. This requires fully personalized external fixators to improve its fit and functionality. This paper presents a methodology to design personalized lightweight external fixator devices for additive manufacturing. This methodology comprises data acquisition, Computer tomography (CT) imaging analysis and processing, Computer Aided Design (CAD) modelling and two methods (imposed predefined patterns and topology optimization) to reduce the weight of the device. Finite element analysis with full factorial design of experiments were used to determine the optimal combination of designs (topology optimization and predefined patterns), materials (polylactic acid, acrylonitrile butadiene styrene, and polyamide) and thickness (3, 4, 5 and 6 mm) to maximize the strength and stiffness of the fixator, while minimizing its weight. The optimal parameters were found to correspond to an external fixator device optimized by topology optimization, made in polylactic acid with 4 mm thickness
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