901 resultados para Mill Neck


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Background: In this study, the efficiency of Guar gum as a biopolymer has been compared with two other widely used inorganic coagulants, ferric chloride (FeCl3) and aluminum chloride (AlCl3), for the treatment of effluent collected from the rubber-washing tanks of a rubber concentrate factory. Settling velocity distribution curves were plotted to demonstrate the flocculating effect of FeCl3, AlCl3 and Guar gum. FeCl3 and AlCl3 displayed better turbidity removal than Guar gum at all settling velocities.

Result: FeCl3, AlCl3 and Guar gum removed 92.8%, 88.2% and 88.1% turbidity, respectively, of raw wastewater at a settling velocity of 0.1 cm min-1, respectively. Scanning electron microscopic (SEM) study conducted on the flocs revealed that Guar gum and FeCl3produced strong intercoiled honeycomb patterned floc structure capable of entrapping suspended particulate matter. Statistical experimental design Response Surface Methodology (RSM) was used to design all experiments, where the type and dosage of flocculant, pH and mixing speed were taken as control factors and, an optimum operational setting was proposed.

Conclusion: Due to biodegradability issues, the use of Guar gum as a flocculating agent for wastewater treatment in industry is highly recommended.

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Background: Evidence for non-steroidal anti-inflammatory drugs (NSAIDs) preventing head and neck cancer (HNC) is inconclusive; however, there is some suggestion that aspirin may exert a protective effect.

Methods: Using data from the United States National Cancer Institute Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial, we examined the association between aspirin and ibuprofen use and HNC.

Results: Regular aspirin use was associated with a significant 22% reduction in HNC risk. No association was observed with regular ibuprofen use.

Conclusion: Aspirin may have potential as a chemopreventive agent for HNC, but further investigation is warranted.

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It is estimated that 60% of patients diagnosed with head and neck cancer will receive radiotherapy at some stage in their disease trajectory. The aim of this literature review was to find and analyse papers pertaining to the lived experiences of patients with head and neck cancer receiving radiotherapy. The review identified a limited number of high-quality research papers focusing on this topic, with only 10 papers fitting the inclusion/exclusion criteria. The majority of the investigative studies were not generalisable owing to small sample sizes and many of them being conducted in only one centre. However, the findings do highlight and contribute to the understanding of the lived experiences of this patient group and provide some insight into the unique physical, social, and psychological difficulties they encounter as a result of their treatment. There appears to be a need for further high-level research into these patients, particularly focusing on the provision of support and information prior to, during, and following radiotherapy. Further attention needs to be paid to preparing patients for the slow recovery following radiotherapy. Interventional studies are also required to develop clinical guidelines and protocols that can assist health professionals in meeting the holistic needs of this patient group.

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Recovery of cellulose fibres from paper mill effluent has been studied using common polysaccharides or biopolymers such as Guar gum, Xanthan gum and Locust bean gum as flocculent. Guar gum is commonly used in sizing paper and routinely used in paper making. The results have been compared with the performance of alum, which is a common coagulant and a key ingredient of the paper industry. Guar gum recovered about 3.86 mg/L of fibre and was most effective among the biopolymers. Settling velocity distribution curves demonstrated that Guar gum was able to settle the fibres faster than the other biopolymers; however, alum displayed the highest particle removal rate than all the biopolymers at any of the settling velocities. Alum, Guar gum, Xanthan gum and Locust bean gum removed 97.46%, 94.68%, 92.39% and 92.46% turbidity of raw effluent at a settling velocity of 0.5 cm/min, respectively. The conditions for obtaining the lowest sludge volume index such as pH, dose and mixing speed were optimised for guar gum which was the most effective among the biopolymers. Response surface methodology was used to design all experiments, and an optimum operational setting was proposed. The test results indicate similar performance of alum and Guar gum in terms of floc settling velocities and sludge volume index. Since Guar gum is a plant derived natural substance, it is environmentally benign and offers a green treatment option to the paper mills for pulp recycling.

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Background: The association between body size and head and neck cancers (HNCA) is unclear, partly because of the biases in case–control studies. Methods: In the prospective NIH–AARP cohort study, 218,854 participants (132,288 men and 86,566 women), aged 50 to 71 years, were cancer free at baseline (1995 and 1996), and had valid anthropometric data. Cox proportional hazards regression was used to examine the associations between body size and HNCA, adjusted for current and past smoking habits, alcohol intake, education, race, and fruit and vegetable consumption, and reported as HR and 95% confidence intervals (CI). Results: Until December 31, 2006, 779 incident HNCAs occurred: 342 in the oral cavity, 120 in the oro- and hypopharynx, 265 in the larynx, 12 in the nasopharynx, and 40 at overlapping sites. There was an inverse association between HNCA and body mass index, which was almost exclusively among current smokers (HR = 0.76 per each 5 U increase; 95% CI, 0.63–0.93), and diminished as initial years of follow-up were excluded. We observed a direct association with waist-to-hip ratio (HR = 1.16 per 0.1 U increase; 95% CI, 1.03–1.31), particularly for cancers of the oral cavity (HR, 1.40; 95% CI, 1.17–1.67). Height was also directly associated with total HNCAs (P = 0.02), and oro- and hypopharyngeal cancers (P < 0.01). Conclusions: The risk of HNCAs was associated inversely with leanness among current smokers, and directly with abdominal obesity and height. Impact: Our study provides evidence that the association between leanness and risk of HNCAs may be due to effect modification by smoking. Cancer Epidemiol Biomarkers Prev; 23(11); 2422–9. ©2014 AACR.

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Novel nucleoside analogues containing photoswitchable moieties were prepared using 'click' cycloaddition reactions between 5 '-azido-5 '-deoxythymidine and mono- or bis-N-propargylamide-substituted azobenzenes. In solution, high to quantitative yields were achieved using 5mol% Cu(I) in the presence of a stabilizing ligand. 'Click' reactions using the monopropargylamides were also effected in the absence of added cuprous salts by the application of liquid assisted grinding (LAG) in metallic copper reaction vials. Specifically, high speed vibration ball milling (HSVBM) using a 3/32('') (2.38mm) diameter copper ball (62mg) at 60Hz overnight in the presence of ethyl acetate lead to complete consumption of the 5 '-azido nucleoside with clean conversion to the corresponding 1,3-triazole.

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Milling is an important operation in many industries, such as mining and pharmaceutical. Although the comminution process during milling has been extensively studied, the material fragmentation mechanisms in a mill are still not well understood partly because of the lack of an understanding on the local stressing and dynamic information under operational conditions in mills. This paper presents a DEM simulation of particle dynamics and impact events in a centrifugal impact pin mill. The main focus is the statistical characteristics of the dominant stressing modes during the milling process. The frequency, velocity and force of the different impact events between particles and mill components, or between particles, are analysed. © 2013 AIP Publishing LLC.

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Objectives: Approximately 300 people are diagnosed with Head and Neck cancer annually in Northern Ireland. The management may include treatment by surgery or by chemotherapy and radiotherapy,
or a combination of modalities. Patients whose oral cavity, teeth, salivary glands and jaws that
will be affected by treatment, particularly radiotherapy should have a pre-treatment assessment. This should be done as early as possible to maximise the time available for dental management. However, this can be challenging owing to the complexities of cancer diagnosis, treatment planning and multidisciplinary management. At the Belfast Dental Hospital, a number of patients were referred post- radiotherapy with complications after not having received a pre-treatment assessment. The referrals for pre- treatment dental assessment were also late in patients’ multidisciplinary journey, limiting the time period
for dental input. The purpose of this audit was to examine the time period between dental assessment and commencement of radiotherapy and whether this was an adequate time frame for dental management. This audit will also examine the dental diseases present and the treatments required pre-radiotherapy. Methods: Data for this audit was collected over 4 months in 2012
by analysing the dental charts and referrals of new patients who were referred to and attended the dental head and neck oncology clinic. A standardised referral pro-forma was introduced from September 2013 to improve the referral process.
A re-audit was conducted over 4 months in 2014. Data was collected similarly as previous. The time period between dental assessment and commencement of radiotherapy was examined. The presence of dental disease and subsequent treatments required were also noted.
Results: 63 new patients were examined in the dental head and neck oncology clinic over 4 months in 2012. 48 (76.2%) were examined pre-radiotherapy. The average length of time between dental assessment and radiotherapy commencement was 11 days. A new standardised referral pro-forma was introduced in 2013. In the re-audit, 65 new patients were seen over 4 months in 2014.
60 (92.3%) patients were examined pre-radiotherapy. The average length of time between dental assessment and radiotherapy commencement was 18 days.
Conclusion: Given the high prevalence of pre-existing dental disease amongst head and neck cancer patients, prompt dental assessment and treatment is vital. Efforts aimed at improving the care pathway are on-going through the implementation of a mandatory referral pro-forma and a dedicated assessment clinic.

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Background: Upon completion of Specialty Training in Restorative Dentistry, trainees (StRs) should
be proficient in maxillofacial prosthodontics to meet the restorative needs of head and neck cancer patients (HANC), and in preparation for the Intercollegiate Specialty Fellowship Examination (ISFE).1,2
Objective: The aim of this study is to collate and compare data relating to the training of Restorative Dentistry Rs in the management of HANC patients across different geographical locations within the British Isles. Methods: Current trainees were invited to complete an online questionnaire by the Specialty Registrars in Restorative Dentistry Group (SRRDG). Participants were asked to rate their confidence and experience in assessing and planning treatment for HANC patients, attending theatre and manufacturing surgical obturators, and in providing implants for appropriate cases. Respondents were also asked to appraise clinical and didactic teaching within their unit, and to rate their confidence of passing oncology- based questions in a future ISFE. Results: Responses were obtained from 21 StRs (n=21) training in all five countries within the British Isles. Most respondents were based in England (76%). A third were in their 5th year of training. Less than half reported that they were confident
of independently assessing (48%) or treatment planning (38%) HANC patients. More than half of StRs (52%) indicated that they were not confident of attending theatres alone and manufacturing a surgical obturator. One third (33%) rated their experience of treating oncology patients with implants as poor or very poor, including three in their 5th year of training. Less than one third rated didactic teaching in maxillofacial prosthodontics at their unit as good or excellent. Only 4 respondents indicated that they were confident of answering an ISFE oncology question on management of healthcare delivery. Six StRs expressed concerns over a lack of case-based exposure.
Conclusion: Experience and training in maxillofacial prosthodontics is inconsistent for StRs across the British Isles with many lacking in clinical exposure.

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BACKGROUND: Head and neck (H&N) cancers are a heterogeneous group of malignancies, affecting various sites, with different prognoses. The aims of this study are to analyse survival for patients with H&N cancers in relation to tumour location, to assess the change in survival between European countries, and to investigate whether survival improved over time.
METHODS: We analysed about 250,000 H&N cancer cases from 86 cancer registries (CRs). Relative survival (RS) was estimated by sex, age, country and stage. We described survival time trends over 1999-2007, using the period approach. Model based survival estimates of relative excess risks (RERs) of death were also provided by country, after adjusting for sex, age and sub-site.
RESULTS: Five-year RS was the poorest for hypopharynx (25%) and the highest for larynx (59%). Outcome was significantly better in female than in male patients. In Europe, age-standardised 5-year survival remained stable from 1999-2001 to 2005-2007 for laryngeal cancer, while it increased for all the other H&N cancers. Five-year age-standardised RS was low in Eastern countries, 47% for larynx and 28% for all the other H&N cancers combined, and high in Ireland and the United Kingdom (UK), and Northern Europe (62% and 46%). Adjustment for sub-site narrowed the difference between countries. Fifty-four percent of patients was diagnosed at advanced stage (regional or metastatic). Five-year RS for localised cases ranged between 42% (hypopharynx) and 74% (larynx).
CONCLUSIONS: This study shows survival progresses during the study period. However, slightly more than half of patients were diagnosed with regional or metastatic disease at diagnosis. Early diagnosis and timely start of treatment are crucial to reduce the European gap to further improve H&N cancers outcome.

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Aims. 2P/Encke is a short period comet that was discovered in 1786 and has been extensively observed and studied for more than 200years. The Taurid meteoroid stream has long been linked with 2P/Encke owing to a good match of their orbital elements, even thoughthe comet’s activity is not strong enough to explain the number of observed meteors. Various small near-Earth objects (NEOs) havebeen discovered with orbits that can be linked to 2P/Encke and the Taurid meteoroid stream. Maribo and Sutter’s Mill are CM typecarbonaceous chondrite that fell in Denmark on January 17, 2009 and April 22, 2012, respectively. Their pre-atmospheric orbits placethem in the middle of the Taurid meteoroid stream, which raises the intriguing possibility that comet 2P/Encke could be the parentbody of CM chondrites.
Methods. To investigate whether a relationship between comet 2P/Encke, the Taurid complex associated NEOs, and CM chondritesexists, we performed photometric and spectroscopic studies of these objects in the visible wavelength range. We observed 2P/Enckeand 10 NEOs on August 2, 2011 with the FORS instrument at the 8.2 m Very Large Telescope on Cerro Paranal (Chile).
Results. Images in the R filter, used to investigate the possible presence of cometary activity around the nucleus of 2P/Encke andthe NEOs, show that no resolved coma is present. None of the FORS spectra show the 700 nm absorption feature due to hydratedminerals that is seen in the CM chondrite meteorites. All objects show featureless spectra with moderate reddening slopes at λ < 800nm. Apart for 2003 QC10 and 1999 VT25, which show a flatter spectrum, the spectral slope of the observed NEOs is compatible withthat of 2P/Encke. However, most of the NEOs show evidence of a silicate absorption in lower S/N data at λ > 800 nm, which is notseen in 2P/Encke, which suggests that they are not related.
Conclusions. Despite similar orbits, we find no spectroscopic evidence for a link between 2P/Encke, the Taurid complex NEOs andthe Maribo and Sutter’s Mill meteorites. However, we cannot rule out a connection to the meteorites either, as the spectral differencesmay be caused by secondary alteration of the surfaces of the NEOs. 

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Michaelis–Arbuzov reactions of S-aryl disulfide derivatives of 3′-thiothymidine or 5′-thioadenosine with tris(trimethylsilyl) phosphite proceeded in high yields to the corresponding phosphorothiolate monoesters. Subsequent hydrolytic desilylation and phosphate coupling were effected in one-pot using liquid-assisted grinding in a vibration ball mill. Novel 3′,5′- and 5′,5′-pyrophosphorothiolate-linked dinucleoside cap analogues were thereby prepared.