Nano-carriers (NCs) provide drugs with protective and oriented strategies. Despite their success in parenteral administration, NCs still need to be optimized to meet the more serious obstacles ...encountered in the gastrointestinal tract (GIT). The main defense mechanisms include renewing mucus, epithelial obstacles and digestion by GIT segments. These hurdles pose challenges even before NCs target molecules or proteins, which has often led to unsatisfactory delivery efficiency. Therefore, a critical focus is the exemption from negative effects of GIT. A series of adapted NCs have been designed based on surface strategies to form an expected distribution and increase gastrointestinal utilization. In this paper, we review the strategies and efforts of NCs to adapt to gastrointestinal defense components, including the mucus, epithelium and gastrointestinal segments; the related gastrointestinal mechanisms and functions are also summarized synchronously. Last, we discuss the delivery challenges in terms of physiopathological GIT and surface properties of the NCs.
Understanding how to mitigate language barriers is becoming increasingly important for health care providers around the world. Language barriers adversely affect patients in their access to health ...services; comprehension and adherence; quality of care; and patient and provider satisfaction. In 2003, the United States (US) government made a major change in national policy guidance that significantly affected limited English proficient patients’ ability to access language services.
The objectives of this paper are to describe the state of the language barriers literature inside and outside the US since 2003 and to compare the research that was conducted before and after a national policy change occurred in the US. We hypothesize that language barrier research would increase inside and outside the US but that the increase in research would be larger inside the US in response to this national policy change.
We reviewed the research literature on language barriers in health care and conducted a cross sectional analysis by tabulating frequencies for geographic location, language group, methodology, research focus and specialty and compared the literature before and after 2003.
Our sample included 136 studies prior to 2003 and 426 studies from 2003 to 2010. In the 2003–2010 time period there was a new interest in studying the providers’ perspective instead of or in addition to the patients’ perspective. The methods remained similar between periods with greater than 60% of studies being descriptive and 12% being interventions.
There was an increase in research on language barriers inside and outside the US and we believe this was larger due to the change in the national policy. We suggest that researchers worldwide should move away from simply documenting the existence of language barriers and should begin to focus their research on documenting how language concordant care influences patient outcomes, providing evidence for interventions that mitigate language barriers, and evaluating the cost effectiveness of providing language concordant care to patients with language barriers. We think this is possible if funding agencies around the world begin to request proposals for these types of research studies. Together, we can begin document meaningful ways to provide high quality health care to patients with language barriers.
The work examines noise barriers and evaluates their effectiveness when changing their geometry and shape. Noise barriers are one of the most effective and widely used methods of reducing noise ...caused by road and railway transport. The effectiveness of the barrier depends on the materials used in the construction, the barrier’s height, geometry, shape, and the acoustic properties of the additional elements installed on top of the barriers. The aim of the work is to review and analyze the scientific literature, which would allow to evaluate the dependence of the acoustic characteristics of noise-reducing barriers on the geometry and shape of the barrier, and to provide recommendations for the design and selection of noise barriers.
THE HNC/HCN RATIO IN STAR-FORMING REGIONS Graninger, Dawn M; Herbst, Eric; Oberg, Karin I ...
The Astrophysical journal,
05/2014, Volume:
787, Issue:
1
Journal Article
Peer reviewed
Open access
HNC and HCN, typically used as dense gas tracers in molecular clouds, are a pair of isomers that have great potential as a temperature probe because of temperature dependent, isomer-specific ...formation and destruction pathways. Previous observations of the HNC/HCN abundance ratio show that the ratio decreases with increasing temperature, something that standard astrochemical models cannot reproduce. We have undertaken a detailed parameter study on which environmental characteristics and chemical reactions affect the HNC/HCN ratio and can thus contribute to the observed dependence. Using existing gas and gas-grain models updated with new reactions and reaction barriers, we find that in static models the H + HNC gas-phase reaction regulates the HNC/HCN ratio under all conditions, except for very early times. We quantitatively constrain the combinations of H abundance and H + HNC reaction barrier that can explain the observed HNC/HCN temperature dependence and discuss the implications in light of new quantum chemical calculations. In warm-up models, gas-grain chemistry contributes significantly to the predicted HNC/HCN ratio and understanding the dynamics of star formation is therefore key to model the HNC/HCN system.
Clinical evidence indicates increased amyloid deposition in HIV-1-infected brains, which contributes to neurocognitive dysfunction in infected patients. Here we show that HIV-1 exposure stimulates ...amyloid beta (Aβ) nuclear entry in human brain endothelial cells (HBMEC), the main component of the blood–brain barrier (BBB). Treatment with HIV-1 and/or Aβ resulted in concurrent increase in early endosomal antigen-1 (EEA1), Smad, and phosphorylated Smad (pSmad) in nuclear fraction of HBMEC. A series of inhibition and silencing studies indicated that Smad and EEA1 closely interact by influencing their own nuclear entry; the effect that was attenuated by dynasore, a blocker of GTP-ase activity of dynamin. Importantly, inhibition of dynamin, EEA1, or TGF-β/Smad effectively attenuated HIV-1-induced Aβ accumulation in the nuclei of HBMEC. The present study indicates that nuclear uptake of Aβ involves the dynamin-dependent EEA1 and TGF-β/Smad signaling pathways. These results identify potential novel targets to protect against HIV-1-associated dysregulation of amyloid processes at the BBB level.
•HIV-1 induces nuclear accumulation of amyloid beta (Aβ) in brain endothelial cells.•EEA-1 and TGF-Β/Smad act in concert to regulate nuclear entry of Aβ.•Dynamin appropriates the EEA-1 and TGF-Β/Smad signaling.•Dynamin serves as a master regulator of HIV-1-induced nuclear accumulation of Aβ.
Epithelial cells are the most common cell type in all animals, forming the sheets and tubes that compose most organs and tissues. Apical-basal polarity is essential for epithelial cell form and ...function, as it determines the localization of the adhesion molecules that hold the cells together laterally and the occluding junctions that act as barriers to paracellular diffusion. Polarity must also target the secretion of specific cargoes to the apical, lateral or basal membranes and organize the cytoskeleton and internal architecture of the cell. Apical-basal polarity in many cells is established by conserved polarity factors that define the apical (Crumbs, Stardust/PALS1, aPKC, PAR-6 and CDC42), junctional (PAR-3) and lateral (Scribble, DLG, LGL, Yurt and RhoGAP19D) domains, although recent evidence indicates that not all epithelia polarize by the same mechanism. Research has begun to reveal the dynamic interactions between polarity factors and how they contribute to polarity establishment and maintenance. Elucidating these mechanisms is essential to better understand the roles of apical-basal polarity in morphogenesis and how defects in polarity contribute to diseases such as cancer.
This study provides a twenty-two-year record of in situ degradation of chlorinated organic compounds by a granular iron permeable reactive barrier (PRB). Groundwater concentrations of trichloroethene ...(TCE) entering the PRB were as high as 10670 μg/L. Treatment efficiency ranged from 81 to >99%, and TCE concentrations from <1 μg/L to 165 μg/L were detected within and hydraulically down-gradient of the PRB. After 18 years, effluent TCE concentrations were above the maximum contaminant level (MCL) along segments of the PRB exhibiting upward trending influent TCE. Degradation products included cis-dichloroethene ( cis-DCE), vinyl chloride (VC), ethene, ethane, >C4 compounds, and possibly CO
and methane. Abiotic patterns of TCE degradation were indicated by compound-specific stable isotope data and the distribution of degradation products. δ
C values of methane within and down-gradient of the PRB varied widely from -94‰ to -16‰; these values cover most of the isotopic range encountered in natural methanogenic systems. Methanogenesis is a sink for inorganic carbon in zerovalent iron PRBs that competes with carbonate mineralization, and this process is important for understanding pore-space clogging and longevity of iron-based PRBs. The carbon isotope signatures of methane and inorganic carbon were consistent with open-system behavior and 22% molar conversion of CO
to methane.
Due to expected benefits such as citizen participation and innovation, the release of Public Sector Information as open data is getting increased attention on various levels of government. However, ...currently data release by governments is still novel and there is little experience and knowledge thus far about its benefits, costs and barriers. This is compounded by a lack of understanding about how internal processes influence data release. Our aim in this paper is to get a better understanding of these processes and how they influence data release, i.e., to find determinants for the release of public sector information. For this purpose, we conducted workshops, interviews, questionnaires, desk research and practice based cases in the education program of our university, involving six local public sector organizations. We find that the way data is stored, the way data is obtained and the way data is used by a department are crucial indicators for open data release. We conclude with the lessons learned based on our research findings. These findings are: we should take a nuanced approach towards data release, avoid releasing data for its own sake, and take small incremental steps to explore data release.
•We examined six public sector organizations aiming to release open data.•Decentralized data storage acts as a barrier to data release.•External data sourcing acts as a barrier to data release.•Not using data in the core process of a public service acts as barrier to data release.
The circular economy concept is much discussed in the European Union (EU), but only limited progress has been accomplished so far regarding its implementation. Most scholarly studies blame this on ...various technological barriers. Our work rebuts these studies. We present the first large-N-study on circular economy barriers in the EU (208 survey respondents, 47 expert interviews). We find that cultural barriers, particularly a lack of consumer interest and awareness as well as a hesitant company culture, are considered the main circular economy barriers by businesses and policy-makers. These are driven by market barriers which, in turn, are induced by a lack of synergistic governmental interventions to accelerate the transition towards a circular economy. Meanwhile, not a single technological barrier is ranked among the most pressing circular economy barriers, according to our research. Overall, our work suggests that circular economy is a niche discussion among sustainable development professionals at this stage. Significant efforts need to be undertaken for the concept to maintain its momentum.
•The first large-N-study on barriers to the circular economy (CE) in the European Union (EU).•The core barriers are cultural (lack of consumer interest/awareness, hesitant company culture).•The CE concept is still a niche discussion among sustainable development professionals.
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