23 research outputs found

    Gold nanoparticles assembled with dithiocarbamate-anchored molecular wires

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    A protocol for the bottom-up self-assembly of nanogaps is developed through molecular linking of gold nanoparticles (AuNPs). Two €-conjugated oligo(phenylene ethynylene) molecules (OPE) with dithiocarbamate anchoring groups are used as ligands for the AuNPs. OPE-4S with a dithiocarbamate in each end of the molecule and a reference molecule OPE-2S with only a single dithiocarbamate end group. The linking mechanism of OPE-4S is investigated by using a combination of TEM, UV-Vis absorption and surface enhanced Raman spectroscopy (SERS) as well as studying the effect of varying the OPE-4S to AuNP concentration ratio. UV-Vis absorption confirms the formation of AuNP aggregates by the appearance of an extended plasmon band (EPB) for which the red shift and intensity depend on the OPE-4S:AuNP ratio. SERS confirms the presence of OPE-4S and shows a gradual increase of the signal intensity with increasing OPE-4S:AuNP ratios up to a ratio of about 4000, after which the SERS intensity does not increase significantly. For OPE-2S, no linking is observed below full coverage of the AuNPs indicating that the observed aggregate formation at high OPE-2S:AuNP ratios, above full AuNP coverage, is most likely of a physical nature (van der Waals forces or €-€ interactions)

    Parenteral Medication Prescriptions, Dispensing and Administration Habits in Mongolia

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    High levels of injection prescribing were reported in Mongolia. Understanding the factors influencing the injection prescribing is essential to reduce their inappropriate use. The study evaluated the views, experiences and attitudes of community members associated with the prescribing of injections in Mongolia. A structured questionnaire focusing on respondents’ characteristics, experiences and views about injections was developed and administered face-to-face to community members in Ulaanbaatar, Mongolia. Standard descriptive statistics were used to summarize demographic data and responses to the questionnaires. Dependant variables were compared using Kruskal-Wallis Tests for independence. Statistical analyses were performed using SPSS Version 21.0. Six hundred participants were approached and the response rate was 79% (n 474). Almost half of the respondents were aged between 31 and 50 (n 228, 48.1%) and 40.9% of respondents were male (n 194). Most respondents were from Ulaanbaatar city (n 407, 85.7%). All respondents had received injections in the past and 268 (56.5%) had received injection in the past year. The most common reason for having an injection in the past year was reported as treatment of a disease (n 163, 60.8%), or for administration of vitamins (n 70, 26.1%). Injections were prescribed by a doctor (n 353, 74.9%), dispensed by a pharmacist (n 283, 59.7%) and administered by a nurse (n 277, 54.9%). Only 16% of all respondents had the expectation of receiving injections when they visited a doctor (n 77). An important perception regarding injections was that they hastened the recovery process (n 269, 56.8%). When asked their opinion about therapeutic injections, 40% of all respondents agreed that injections were a better medicine (n 190) than oral medications, with older respondents strongly agreeing (p<0.001). Based on this total sample, approximately 1891 injections per 1000 patients were administered. The excessive injection use seems to be promoted by inappropriate prescribing, dispensing and administration of medication by doctors and others

    Gold nanoparticles assembled with dithiocarbamate-anchored molecular wires

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    A protocol for the bottom-up self-assembly of nanogaps is developed through molecular linking of gold nanoparticles (AuNPs). Two €-conjugated oligo(phenylene ethynylene) molecules (OPE) with dithiocarbamate anchoring groups are used as ligands for the AuNPs. OPE-4S with a dithiocarbamate in each end of the molecule and a reference molecule OPE-2S with only a single dithiocarbamate end group. The linking mechanism of OPE-4S is investigated by using a combination of TEM, UV-Vis absorption and surface enhanced Raman spectroscopy (SERS) as well as studying the effect of varying the OPE-4S to AuNP concentration ratio. UV-Vis absorption confirms the formation of AuNP aggregates by the appearance of an extended plasmon band (EPB) for which the red shift and intensity depend on the OPE-4S:AuNP ratio. SERS confirms the presence of OPE-4S and shows a gradual increase of the signal intensity with increasing OPE-4S:AuNP ratios up to a ratio of about 4000, after which the SERS intensity does not increase significantly. For OPE-2S, no linking is observed below full coverage of the AuNPs indicating that the observed aggregate formation at high OPE-2S:AuNP ratios, above full AuNP coverage, is most likely of a physical nature (van der Waals forces or €-€ interactions)

    Social and cultural dimensions of hygiene in Cambodian health care facilities

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    <p>Abstract</p> <p>Background</p> <p>The frequency of bloodborne pathogen healthcare-associated infections is thought to be high in developing Southeast Asian Countries. The underlying social-cultural logics contributing to the risks of transmission are rarely studied. This report provides some insights on the social and cultural factors that shape hygiene practices in Cambodian health care settings.</p> <p>Methods</p> <p>We conducted qualitative surveys in various public and private health facilities in Phnom Penh, the capital city and in provinces. We observed and interviewed 319 participants, health care workers and patients, regarding hygiene practices and social relationships amongst the health care staff and with patients. We also examined the local perceptions of hygiene, their impact on the relationships between the health care staff and patients, and perceptions of transmission risks. Data collection stem from face to face semi-structured and open-ended interviews and focus group discussions with various health care staffs (i.e. cleaners, nurses, midwives and medical doctors) and with patients who attended the study health facilities.</p> <p>Results</p> <p>Overall responses and observations indicated that hygiene practices were burdened by the lack of adequate materials and equipements. In addition, many other factors were identified to influence and distort hygiene practices which include (1) informal and formal social rapports in hospitals, (2) major infection control roles played by the cleaners in absence of professional acknowledgment. Moreover, hygiene practices are commonly seen as an unessential matter to be devoted to low-ranking staff.</p> <p>Conclusion</p> <p>Our anthropological findings illustrate the importance of comprehensive understanding of hygiene practices; they need to be considered when designing interventions to improve infection control practices in a Cambodian medical setting.</p

    Anthropological perspectives on injections: a review.

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    Qualitative studies from developing countries have pointed to the widespread popularity of injections. In addition to their use by formal and informal providers and traditional healers, there is now increasing evidence of the use of injections and injection equipment by lay people. Epidemiological research links the large number of unsafe injections to serious bloodborne infections such as viral hepatitis B and C and acquired immunodeficiency syndrome (AIDS). The present article examines the reasons behind the demand for injections by consumers and the administration of unnecessary or unsafe injections by different types of provider. Interventions aimed at reducing the risk of unsafe injections are discussed in relation to cultural and social factors as well as those factors associated with health systems. Suggestions are made for approaches to the design of such interventions
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