Curvature dependence of the effect of ionic functionalization on the attraction among nanoparticles in dispersion

Solubilization of nanoparticles facilitates nanomaterial processing and enables new applications. An effective method to improve dispersibility in water is provided by ionic functionalization.We explore how the necessary extent of functionalization depends on the particle geometry. Using molecular dynamics/umbrella sampling simulations, we determine the effect of the solute curvature on solventaveraged interactions among ionizing graphitic nanoparticles in aqueous dispersion. We tune the hydrophilicity of molecular-brush coated fullerenes, carbon nanotubes, and graphane platelets by gradually replacing a fraction of the methyl end groups of the alkyl coating by the ionizing –COOK or –NH3Cl groups. To assess the change in nanoparticles’ dispersibility in water, we determine the potential-of-mean-force profiles at varied degrees of ionization. When the coating comprises only propyl groups, the attraction between the hydrophobic particles intensifies from spherical to cylindrical to planar geometry. This is explained by the increasing fraction of surface groups that can be brought into contact and the reduced access to water molecules, both following the above sequence. When ionic groups are added, however, the dispersibility increases in the opposite order, with the biggest effect in the planar geometry and the smallest in the spherical geometry. These results highlight the important role of geometry in nanoparticle solubilization by ionic functionalities, with about twice higher threshold surface charge necessary to stabilize a dispersion of spherical than planar particles. At 25%–50% ionization, the potential of mean force reaches a plateau because of the counterion condensation and saturated brush hydration. Moreover, the increase in the fraction of ionic groups can weaken the repulsion through counterion correlations between adjacent nanoparticles. High degrees of ionization and concomitant ionic screening gradually reduce the differences among surface interactions in distinct geometries until an essentially curvature-independent dispersion environment is created. Insights into tuning nanoparticle interactions can guide the synthesis of a broad class of nonpolar nanoparticles, where solubility is achieved by ionic functionalization

Randomized, double-blind comparison of once-weekly dalbavancin versus twice-daily linezolid therapy for the treatment of complicated skin and skin structure infections

Background. Dalbavancin, a novel lipoglycopeptide with a pharmacokinetic profile that allows weekly dosing, is active against gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA). The efficacy of dalbavancin for treatment of skin and skin structure infections (SSSIs) was demonstrated in a phase 2 study. Methods. In a phase 3 noninferiority study, patients with complicated SSSIs, including infections known or suspected to involve MRSA, were randomized (ratio, 2:1) in a double-blind manner to receive dalbavancin (1000 mg given intravenously on day 1 and 500 mg given intravenously on day 8) or linezolid (600 mg given intravenously or intravenously/orally every 12 h for 14 days). Efficacy was assessed by determining clinical and microbiological responses at the end of therapy and at the test-of-cure visit. Relapses were identified by additional follow-up ~1 month later. Results. MRSA was identified in 51% of patients from whom a pathogen was isolated at baseline. Dalbavancin and linezolid demonstrated comparable clinical efficacy in the clinically evaluable population at the test-of-cure visit (88.9% and 91.2% success, respectively). The rate of clinical success at the end of therapy was >90% in both arms. Less than 1.0% of patients in either treatment arm experienced relapse after the test-of-cure visit. Both treatments yielded successful microbiological response in excess of 85% among microbiologically evaluable patients at end of therapy and at the test-of-cure visit for all pathogens combined, for all S. aureus strains, and for MRSA. Gastrointestinal symptoms were among the most common adverse events in both arms. A higher proportion of patients in the linezolid arm reported adverse events that were judged by the investigator to be probably/possibly related to treatment (dalbavancin arm, 25.4% of subjects; linezolid arm, 32.2% of subjects). Conclusions. Two doses of dalbavancin (1000 mg given on day 1 followed by 500 mg given on day 8) were as well tolerated and as effective as linezolid given twice daily for 14 days for the treatment of patients with complicated SSSI, including those infected with MRSA.Peer reviewe

Excess-entropy scaling in supercooled binary mixtures

Supercooled liquids near the glass transition show remarkable non-Arrhenius transport phenomena, whose origin is yet to be clarified. Here, the authors use GPU molecular dynamics simulations for various binary mixtures in the supercooled regime to show the validity of a quasiuniversal excess-entropy scaling relation for viscosity and diffusion

Work-related stress and interruptions in the emergency department

The impact of interruptions in the workplace has begun to receive a lot of attention in the last few years (Mark, Klocke, 2008). Different studies have shown that interruptions can result in lapses of attention, memory or perception increasing cognitive load, stress and anxiety, deteriorating decision-making performance, but data are not always convergent (Hudson et al., 2002). In particular, in healthcare only limited evidence (Ebright et al., 2003) has been available. This study investigated the impact of interruption of physician stress in an emergency care department of an Italian Hospital. A total amount of 180 h of observation were performed. Observed physicians were evaluated for cognitive level of stress before and after the observed work shift. Visual analogical measures and a Self-Perceived Stress scale were used. We also evaluated personality dimensions using the BIS/BAS scale (Carver and Whyte, 1994). BIS reflects a reaction towards events that occurred (like interruptions), and hence a sensitivity to these events. We found that doctors were typically interrupted 7.1 times per hour; 18% percent of all tasks were interrupted. Consistent with the literature, the sources of interruptions most often were other physicians (23%), and fixed telephone (21%). In 84% of the interruptions, physicians returned to the interrupted activity; in 16% they did not. Interruptions led emergency department doctors to spend less time on the tasks they were working on. Furthermore, a signi ficant correlation between the number of interruption and the level of stress variation was found. We also found that doctors with higher scores at the BIS scale actually showed higher level of work related stress, but we didn't' find a correlation with the number of interruptions experienced. The study suggests that interrupted physicians often experience a higher workload, more stress, more time pressure, leading people to change not only work regularity but also mental and physiological states. The e ffect of this change might be mediated by some biological and personality dimensions. Our data may be a starting point to improve the emergency department sterilization by interruptions helping physician to reduce cognitive workload and stress and thus limiting the potentials effect on adverse events

An Analysis and Comparison of Expectations and Perceptions on Sustainable Tourism among Italian and German Tourists

The paper investigates the relationship of Italian and German consumers with sustainable tourism through a quantitative online questionnaire. The study’s first aim is to understand the representation of sustainable tourism. It also analyzes if the issue of sustainability denotes an abstract or concrete value to consumers, the extent to which sustainability is considered an important factor in the process of purchasing and consumption of a tourism product, and then becomes a driver for consumers to choose from. The analysis of tourist flows and the literature of the field have shown that in Germany there is extensive experience on the topics of sustainability and sustainable tourism, while little has been written on these issues with respect to Italian tourists. The key dimensions of the questionnaire were based on an analysis of the scientific literature of the field and on an earlier qualitative phase carried out through interviews with opinion leaders that have identified main themes, values, expectations, and needs of the consumer of tourism. The questionnaire was divided into three parts: the first explores the socio-demographic characteristics and values, the second tourism habits, the third knowledge, perceptions, attitudes, and behaviors. The results provide a better understanding of the drivers that influence the choice of tourism and have important practical implications for the implementation and communication of sustainable tourism

Evaluasi Pelaksanaan Pelayanan Kefarmasian di Apotek Telemedika Farma 14 Manado

Penelitian ini bersifat deskriptif kualitatif yang bertujuan untuk mendapatkan informasi secara menyeluruh bagaimana sistem pelayanan kefarmasian di Apotek Telemedika Farma 14 Manado. Responden dalam penelitian ini adalah Apoteker Pengelolah Apotek (APA), Tenaga Teknis Kefarmasian. Berdasarkan hasil penelitian maka di dapatkan hasil bahwa standar pelayanan kefarmasian yang ada di Apotek Telemedika Farma 14 Manado belum sepenuhnya menerapkan standar pelayanan kefarmasian berdasarkan Peraturan Menteri Kesehatan. Standar pelayanan kefarmasian pada pelayanan informasi obat tidak dilakukan informasi kepada konsumen terkait farmakokinetik. Pada saat konseling tidak dilakukan konseling yang terdokumentasi. Pelayanan kefarmasian dirumah belum sepenuhnya dilaksanakan. Pemantauan terapi obat tidak melakukan pemilihan pasien sesuai kriteria, dan tidak melakukan dokumentasi pelaksanaa pemantauan terapi obat. Pelayanan Kefarmasian Di Rumah dan Monitoring Efek Samping obat belum dilakukan sepenuhnya

Comparison of the efficacy of ramoplanin and vancomycin in both in vitro and in vivo models of clindamycin-induced Clostridium difficile infection

Treatment of Clostridium difficile infection (CDI) is limited primarily to either metronidazole or vancomycin. We compared vancomycin and a novel glycolipodepsipeptide, ramoplanin, in both hamster and in vitro gut models of clindamycin-induced CDI.Peer reviewe