The Implementation of LAB 2000 and Synergistic Systems in Middle School Laboratories in Virginia

To solve this problem, the following goals were developed: 1. Determine the effectiveness of the high tech laboratories with regard to implementing the middle school curriculum; 2. Make recommendations for facility and curriculum changes based upon the observations of the practicing middle school teachers

Chitosan and its derivatives for application in mucoadhesive drug delivery systems

Mucoadhesive drug delivery systems are desirable as they can increase the residence time of drugs at the site of absorption/action, provide sustained drug release and minimize the degradation of drugs in various body sites. Chitosan is a cationic polysaccharide that exhibits mucoadhesive properties and it has been widely used in the design of mucoadhesive dosage forms. However, its limited mucoadhesive strength and limited water-solubility at neutral and basic pHs are considered as two major drawbacks of its use. Chemical modification of chitosan has been exploited to tackle these two issues. In this review, we highlight the up-to-date studies involving the synthetic approaches and description of mucoadhesive properties of chitosan and chitosan derivatives. These derivatives include trimethyl chitosan, carboxymethyl chitosan, thiolated chitosan, chitosan-enzyme inhibitors, chitosan-ethylenediaminetetraacetic acid (chitosan-EDTA), half-acetylated chitosan, acrylated chitosan, glycol chitosan, chitosan-catechol, methyl pyrrolidinone-chitosan, cyclodextrin-chitosan and oleoyl-quaternised chitosan. We have particularly focused on the effect of chemical derivatization on the mucoadhesive properties of chitosan. Additionally, other important properties including water-solubility, stability, controlled release, permeation enhancing effect, and in vivo performance are also described

Developing mucoadhesive and mucuspenetrating nanoparticles for drug delivery: silica and chitosan models

Mucosal drug delivery is often limited by the presence of several barriers including mucus, the harsh pH and enzymatic activity on the mucosal surfaces. Nanoparticles have shown some potential to overcome these barriers. The aim of this thesis was to investigative how functionalisation of nanoparticles with non-ionic hydrophilic polymers (polyethylene glycol (PEG), polyhydroxyethyl acrylate (PHEA), poly-2-ethyl-2-oxazoline (POZ) and polyvinyl pyrrolidone (PVP)) affects their physicochemical and mucoadhesive properties, diffusion in mucin solution as well as ability to penetrate into mucosal tissues. Silica and chitosan nanoparticles were chosen. Thiolated silica nanoparticles were functionalised with PEG and POZ and therefore three types of silica nanoparticles were obtained; thiolated, PEGylated and POZylated. After the synthesis, the effect of the pH on the size of the silica nanoparticles was studied. No significant change in the size of PEGylated silica nanoparticles over the pH range of 1.5–9 was observed. A significant increase in the size of thiolated and POZylated silica nanoparticles at pH  ≤ 2 was observed. Fluorescently labelled thiolated, PEGylated and POZylated silica nanoparticles were incubated with freshly excised rat intestinal mucosae. Then, the mucosae with the nanoparticles were washed with phosphate buffer solution for several cycles and their fluorescent images were taken. It was found that PEGylated and POZylated silica nanoparticles were less mucoadhesive compared to the thiolated counterpart. This was evident by the lower fluorescence signal of the PEGylated and POZylated silica nanoparticles compared to the thiolated counterpart. Four chitosan derivatives (PEG-, PHEA-, POZ- and PVP-chitosan) were synthesised, which showed complete solubility over a broad pH range (3-9). Unmodified and modified chitosan nanoparticles were prepared using ionic gelation with sodium tripolyphosphate. Modified chitosan nanoparticles diffused faster in bovine submaxillary mucin solution measured by nanoparticle tracking analysis. The penetration of chitosan nanoparticles was evaluated using fluorescence microscopy and demonstrated that modified chitosan nanoparticles penetrated deeper into sheep nasal mucosa compared to unmodified chitosan nanoparticles. The possibilities of incorporating psychoactive drugs (haloperidol and phenobarbital) into unmodified and PVP-chitosan nanoparticles were investigated. Haloperidol-unmodified chitosan nanoparticles showed a relatively low loading capacity. However, phenobarbitalunmodified and PVP-chitosan nanoparticles showed a high loading capacity and provided a sustained drug release. These findings illustrate how the functionalisation of nanoparticles affect their physicochemical properties, which in turn determine their mucoadhesive properties and ability to penetrate mucus. They provide an important contribution to the field of mucosal drug delivery

Silica nanoparticles in transmucosal drug delivery

Transmucosal drug delivery includes the administration of drugs via various mucous membranes, such as gastrointestinal, nasal, ocular, and vaginal mucosa. The use of nanoparticles in transmucosal drug delivery has several advantages, including the protection of drugs against the harsh environment of the mucosal lumens and surfaces, increased drug residence time, and enhanced drug absorption. Due to their relatively simple synthetic methods for preparation, safety profile, and possibilities of surface functionalisation, silica nanoparticles are highly promising for transmucosal drug delivery. This review provides a description of silica nanoparticles and outlines the preparation methods for various core and surface-functionalised silica nanoparticles. The relationship between the functionalities of silica nanoparticles and their interactions with various mucous membranes are critically analysed. Applications of silica nanoparticles in transmucosal drug delivery are also discussed

Synthesis of thiolated, PEGylated and POZylated silica nanoparticles and evaluation of their retention on rat intestinal mucosa in vitro

In this study, we synthesised thiolated silica nanoparticles using 3-mercaptopropyltrimethoxysilane and functionalised them with either 5 kDa methoxy polyethylene glycol maleimide (PEG) or 5 kDa alkyne-terminated poly(2-ethyl-2-oxazoline) (POZ). The main objectives of this study are to investigate the effects of pH on the size and ξ-potential of these nanoparticles and evaluate their mucoadhesive properties ex vivo using rat intestinal mucosa. The sizes of thiolated, PEGylated and POZylated silica nanoparticles were 53 ± 1, 68 ± 1 and 59 ± 1 nm, respectively. The size of both thiolated and POZylated nanoparticles significantly increased at pH ≤ 2, whereas no size change was observed at pH 2.5–9 for both these two types of nanoparticles. On the other hand, the size of PEGylated nanoparticles did not change over the studied pH range (1.5–9). Moreover, thiolated nanoparticles were more mucoadhesive in the rat small intestine than both PEGylated and POZylated nanoparticles. After 12 cycles of washing (with a total of 20 mL of phosphate buffer solution pH 6.8), a significantly greater amount of thiolated nanoparticles remained on the intestinal mucosa than FITC-dextran (non-mucoadhesive polymer, p  0.1 for both). Thus, this study indicates that thiolated nanoparticles are mucoadhesive, whereas PEGylated and POZylated nanoparticles are non-mucoadhesive in the ex vivo rat intestinal mucosa model. Each of these nanoparticles has potential applications in mucosal drug delivery

Estimation of Water and Energy Saving by Rainwater Harvesting: Sulaimani City as a Case Study

Rainwater harvesting could be a possible solution to decrease the consequences of water scarcity and energy deficiency in Iraq and the Kurdistan Region of Iraq (KRI). This study aims to calculate the water and energy (electricity) saved by rainwater harvesting for rooftops and green areas in Sulaimani city, KR, Iraq. Various data were acquired from different formal entities in Sulaimani city. Moreover, Google Earth and ArcMap 10.4 software were used for digitizing and calculating the total rooftop and green areas. The results showed that for the used runoff coefficients (0.8 and 0.95), the harvested rainwater volumes were 2901563 and 12197131 m³ during the study period (2005 – 2006) and (2019-2020). Moreover, by comparing the study area's rainwater harvesting volume and water production, the water-saving percentage was 8.21 to 22.68%. Furthermore, the energy-saving percentage recorded was from 7.70 to 22.5% by implementing rooftop rainwater harvesting. On the other hand, using average daily rainfall data for the year (2005-2020), the total water-saving percentage and the total energy-saving rate for both runoff coefficients were very close. Water and energy-saving results were calculated using year-by-year rainfall data, taking more time and effort for its computation. Moreover, the water-saving percentage for the selected green area was not encouraging, and the results were between 0.73 and 11.15%. Additionally, the storage size for three typical buildings was calculated, and the results show the average storage size required for rainwater harvesting using daily rainfall data was 11.2 to 14.68 m³ (house), 291.42 to 422.33 m³ (school), and 10.5 to 11.41 m³ (hotel) for runoff coefficients of 0.8 and 0.95, respectively.

Evaluation of a multifaceted "Resident-as-Teacher" educational intervention to improve morning report

BACKGROUND: Resident-led morning report is an integral part of most residency programs and is ranked among the most valuable of educational experiences. The objectives of this study were to evaluate the effect of a resident-as-teacher educational intervention on the educational and teaching experience of morning report. METHODS: All senior internal medicine residents were invited to participate in this study as teaching participants. All internal medicine residents and clerks were invited to participate as audience participants. The educational intervention included reading material, a small group session and feedback after teaching sessions. The educational and teaching experiences were rated prior to and three months after the intervention using questionnaires. RESULTS: Forty-six audience participants and 18 teaching participants completed the questionnaires. The degree to which morning report met the educational needs of the audience was higher after the educational intervention (effect size, d = 0.26, p = 0.01). The perceptions of the audience were that delivery had improved and that the sessions were less intimidating and more interactive. The perception of the teaching participants was that delivery was less stressful, but this group now reported greater difficulty in engaging the audience and less confidence in their medical knowledge. CONCLUSION: Following the educational intervention the audience's perception was that the educational experience had improved although there were mixed results for the teaching experience. When evaluating such interventions it is important to evaluate the impact on both the educational and teaching experiences as results may differ

Diabetic autonomic neuropathy: evidence for apoptosis in situ in the rat

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75065/1/j.1365-2982.2004.00524.x.pd