Some edaphic factors related to the distribution of flora (including soil fungi) along the bank of the hiver wear at Shincliffe, county Durham

Not availabl

Soil fertility as a parameter in land evaluation of moorland, Waldridge Fell, County Durham

The aim of these investigations is to assess the importance of soil fertility as a parameter in land evaluation of moorland. Waldridge Fell of County Durham is chosen as a specific reference, and the thesis comprises three parts:- I. General background to the problem, II. The environment of Waldridge Fell and III. Investigations and implications. Part I indicates the contemporary land use in Britain and its relation to the potential of moorland. The present land capability classification of County Durham and Waldridge Fell is reviewed and the approaches to the assessment of biological production in land evaluation are discussed. There follows a resume of moorland soils, and the influence of grazing and afforestation on them. Part II outlines the environmental background of Waldridge Fell, including a detailed description of the study site. The vegetation pattern and the correlated edaphic and biotic variables of the area are analysed in detail. Part III consists of experimental work and its implications. Environmental monitoring, from Nov. I970 - June 1972 was undertaken to investigate the seasonal fluctuations of soil fertility and biological yields of Calluna as affected by the weather conditions. A further assessment of different soils from the research area was undertaken in the laboratory. This leads to conclusions relating to the factors regulating productivity of Calluna in the field. The last chapter integrates soil fertility and the biological productivity assessment in land evaluation. Further analyses were carried out to test the interrelationships between the nutrient contents both in the soils and Calluna tissues, the effects of climate and the productivity of Calluna. The possibility of using soil chemical nutrients as parameters in predicting yield is also discussed

Instant messaging for enquiry-based learning and peer learning communities

Instant Messaging (IM) tools such as Telegram may effectively be used to engage students in their learning. This paper explored how IM can enhance traditional teaching and learning in higher education by creating additional informal learning spaces, rather to disturb the existing classroom practices. There are three objectives that this paper was expected to achieve:- • To measure the student Response rate in using IM for the assessment of effectiveness in enquiry-based learning; • To evaluate the impact of IM on peer-to-peer participation through the analysis of dialogues among the learning communities; and • To discuss the essentials of successful application of IM in informal learning spaces. A module named Highway Engineering (CON4381) of Higher Diploma in Civil Engineering at the Hong Kong Institute of Vocational Education was selected with a large class size of over 300 students. The results were encouraging with over 100 students participated in the learning communities and more than 200 number of questions posed and interaction counts. The activities trends and students’ feedbacks showed positive perception and acceptance of the use of Telegram for teaching and learning. A questionnaire designed by the authors was used at the end of the semester and the participants showed positive perception and acceptance of the use of Telegram for teaching and learning. It was revealed that IM tools could elicit new learning opportunities, foster enquiry-based learning, offer informal and formal learning opportunities, and support peer learning community. A valuable discussion was conducted to address challenges in adopting IM as transmission pedagogy including merging of academic and non-academic contents, perceived distractive nature and potential to trigger off-task behaviours and sometimes limited participation of all students etc. Although such challenges exist in adopting IM as pedagogy, the potential to foster an effective learning environment should not be underestimated. Together with the widespread participation of all students and enhanced willingness on public expression of silenced voices, the utilization of instant messaging was found to be reasonably valid. Furthermore, an investigation into a mobile app which supplemented Vocational Training Council\u27s Moodle learning management platform was made so as to explore further usability whenever appropriate

Esophageal secondary peristalsis following acid infusion and chemical clearance correlate with mucosal integrity and acid sensitivity in GERD patients

BACKGROUND: Acid sensitivity can be altered in patients with gastroesophageal reflux disease (GERD). Secondary peristalsis helps clear gastro-esophageal refluxate and residual ingested food bolus. OBJECTIVES: The aim of this study was to investigate the associations among acid sensitivity, esophageal mucosal integrity, chemical clearance, and secondary peristalsis before and after esophageal acid infusion. DESIGN: This was an investigator-initiated, prospective, cross-sectional study. METHODS: Adult reflux patients underwent high resolution manometry and 24 h impedance-pH monitoring off acid suppression to identify GERD phenotypes, including non-erosive reflux disease (NERD), reflux hypersensitivity (RH), and functional heartburn (FH). Secondary peristalsis was assessed using five rapid 20 mL air injections into the esophagus before and after infusion of hydrochloric acid (0.1 N) into the mid-esophagus. Conventional acid infusion parameters recorded included lag time, intensity rating, and sensitivity score. Chemical clearance was evaluated using the post-reflux swallow-induced peristaltic wave (PSPW), and mucosal integrity was assessed by the mean nocturnal baseline impedance (MNBI) derived from impedance-pH monitoring. RESULTS: A total of 88 patients (age 21-64 years, 62.5% women) completed the study including 12 patients with NERD, 45 with RH, and 31 with FH. There was no significant difference in acid infusion parameters between patients with NERD, RH, and FH. Upon acid infusion, patients who exhibited successful secondary peristalsis had longer lag time, higher MNBI, and shorter bolus contact time than those without secondary peristalsis. Meanwhile, patients with intact PSPW demonstrated significantly higher intensity ratings in response to acid perfusion and higher MNBI than those with impaired PSPW. The lag time correlated positively with MNBI ( CONCLUSION: In conclusion, the protective effect of esophageal secondary peristalsis and chemical clearance on esophageal mucosal integrity was demonstrated. Concerning acid sensitivity, longer lag time in patients with intact secondary peristalsis may be attributed to better esophageal mucosal integrity, while stronger intensity ratings may have a greater tendency to induce PSPW and protect esophageal mucosal integrity

Polarized Secretion of Interleukin (IL)-6 and IL-8 by Human Airway Epithelia 16HBE14o- Cells in Response to Cationic Polypeptide Challenge

BACKGROUND: The airway epithelium participates in asthmatic inflammation in many ways. Target cells of the epithelium can respond to a variety of inflammatory mediators and cytokines. Damage to the surface epithelium occurs following the secretion of eosinophil-derived, highly toxic cationic proteins. Moreover, the surface epithelium itself is responsible for the synthesis and release of cytokines that cause the selective recruitment, retention, and accumulation of various inflammatory cells. To mimic the damage seen during asthmatic inflammation, the bronchial epithelium can be challenged with highly charged cationic polypeptides such as poly-L-arginine. METHODOLOGY/PRINCIPAL FINDINGS: In this study, human bronchial epithelial cells, 16HBE14o- cells, were "chemically injured" by exposing them to poly-l-arginine as a surrogate of the eosinophil cationic protein. Cytokine antibody array data showed that seven inflammatory mediators were elevated out of the 40 tested, including marked elevation in interleukin (IL)-6 and IL-8 secretion. IL-6 and IL-8 mRNA expression levels were elevated as measured with real-time PCR. Cell culture supernatants from apical and basolateral compartments were collected, and the IL-6 and IL-8 production was quantified with ELISA. IL-6 and IL-8 secretion by 16HBE14o- epithelia into the apical compartment was significantly higher than that from the basolateral compartment. Using specific inhibitors, the production of IL-6 and IL-8 was found to be dependent on p38 MAPK, ERK1/2 MAPK, and NF-kappaB pathways. CONCLUSIONS/SIGNIFICANCE: The results clearly demonstrate that damage to the bronchial epithelia by poly-L-arginine stimulates polarized IL-6 and IL-8 secretion. This apically directed secretion of cytokines may play an important role in orchestrating epithelial cell responses to inflammation

Oral health of community dwelling elders in Hong Kong

Introduction: The world’s population is ageing and the elders are vulnerable to oral health problems. This project aimed to observe the oral health status of community dwelling elders in Hong Kong, investigate the oral health impact on their quality of life and nutritional status, and provide oral health education and preventive service. Methods: Community dwelling elders (65 or above) were recruited from five community centers. An interviewer-administered questionnaire was completed to collect information on their socio-demographic background and oral health perception/practice. Their oral health related quality of life (OHQoL) and nutritional status were measured by using the Geriatric Oral Health Assessment Index (GOHAI) and Mini-Nutritional Assessment (MNA), respectively. Their tooth and periodontal status, oral hygiene and soft tissues were examined. Individualized advice, oral health education and scaling were provided. Results: A total of 195 elders participated. Despite their sound knowledge on dental caries, their awareness of the causes and risk factors of periodontal diseases was low. Several misconceptions of oral health were common and their expectation towards oral health was low. Although 81% brush their teeth at least twice a day, over 75% did not perform interdental cleaning mainly due to unawareness of the necessity (32%) and lack of skills (42%). Their dental visits were treatment-driven and mainly for pain-relieving and emergency care. Only 19% were regular dental attendees. The mean (SD) DMFT was 8.9 (7.8). Over 60% had periodontal pockets; 6% were edentulous and 38% had fewer than 20 teeth. The mean (SD) total GOHAI score was 56.4 (8.0); 60% reported negative impact of oral health on their quality of life. The mean (SD) MNA score was 25.2 (2.9); 30% had malnutrition or were at risk. Multivariate analysis showed that tooth loss and untreated decayed teeth (DT) were significant determinants of poor OHQoL; older age, higher education level, and poorer OHQoL were significantly associated with higher risk of malnutrition (all p<0.05). Conclusions: Oral health problems are common among community dwelling elders in Hong Kong. Their oral health awareness and practice are yet to be improved. Tooth loss and unmet treatment need for dental caries significantly compromise elders’ quality of life, which in turn increases their risk for malnutrition. Outreach oral health education and service are well received by the community.published_or_final_versio

Engineering microbes to sense and eradicate Pseudomonas aeruginosa, a human pathogen

A synthetic genetic system is designed and characterized that allows Escherichia coli to sense and eradicate Pseudomonas aeruginosa, providing a novel antimicrobial strategy that could potentially be applied to fighting infectious pathogens

Active RIS-Assisted MIMO-OFDM System: Analyses and Prototype Measurements

In this study, we develop an active reconfigurable intelligent surface (RIS)-assisted multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) prototype compliant with the 5G New Radio standard at 3.5 GHz. The experimental results clearly indicate that active RIS plays a vital role in enhancing MIMO performance, surpassing passive RIS. Furthermore, when considering factors such as complexity, energy consumption, and performance, the comparative evaluation between passive RIS and active RIS reinforces the critical role of active RIS in MIMO systems. These findings underscore the practical significance of active RIS in improving MIMO gain in 5G scenarios.Comment: 5 pages, 6 figures, 1 table. This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

A Study of Success Rate of Miniscrew Implants as Temporary Anchorage Devices in Singapore

Objective. To find out the success rate of miniscrew implants in the National Dental Centre of Singapore (NDCS) and the impact of patient-related, location-related, and miniscrew implant-related factors. Materials and Methods. Two hundred and eighty-five orthodontic miniscrew implants were examined from NDCS patient records. Eleven variables were analysed to see if there is any association with success. Outcome was measured twice, immediately after surgery prior to orthodontic loading (T1) and 12 months after surgery (T2). The outcome at T2 was assessed 12 months after the miniscrew’s insertion date or after its use as a temporary anchorage device has ceased. Results. Overall success rate was 94.7% at T1 and 83.3% at T2. Multivariate analysis revealed only the length of miniscrew implant to be significantly associated with success at both T1 (P=0.002) and T2 (P=0.030). Miniscrew implants with lengths of 10–12 mm had the highest success rate (98.0%) compared to other lengths, and this is statistically significant (P=0.035). At T2, lengths of 10–12 mm had significantly (P=0.013) higher success rates (93.5%) compared to 6-7 mm (76.7%) and 8 mm (82.1%) miniscrew implants. Conclusion. Multivariate statistical analyses of 11 variables demonstrate that length of miniscrew implant is significant in determining success