Explore the vast range of titles available.

Recently developed Nickel-Titanium (NiTi) instruments with practical changes have resulted in safer instrumentation. In addition, topographical features on the file surface are a contributing factor to clinical durability. Therefore, this study aimed to investigate both the cyclic fatigue resistance and the roughness change of MTwo and Rotate instruments (VDW, Munich, Germany). Each instrument (n = 6/each group) was scanned with an atomic force microscopy prior to and after instrumentation. In addition, cyclic fatigue testing was conducted for each instrument (n = 11/each group) with stainless-steel blocks, including 45°-60°-90° degrees of curvature milled to the instruments’ size. The roughness parameters increased for both systems after instrumentation (p<0.05). Both systems presented an increased roughness following instrumentation (p<0.05). The cyclic fatigue resistance was lowest at 90° for both systems (p<0.05), whereas the Rotate files presented a higher resistance than that of the Mtwo files (p<0.05). Compared to the Mtwo files, Rotate files presented better resistance, while the resistance decreased as the curvature increased.

The focus for the exhibition was Jane Austen’s writing slope, on loan from the British Library. In Training for a Heroine: An Exhibition of Jane Austen’s Travelling Writing Desk [ Image Omitted ] Jane Austen’s traveling writing desk belonged to the author from 1794 until her death in 1817. A recipe can be found in a handwritten household book owned by Martha Lloyd, a family friend of the Austens who lived with them in both Southampton and Chawton. Take 4 oz: of blue gauls, 2 oz: of green Copperas 1 oz & half of gum Arrabic, break the galls, the gum & Copperas must be beaten in a Mortar & put into a pint of strong stale Beer; with a pint of small Beer, put in a little double refin’d Sugar, it must stand in a chimney Corner fourteen days & shaken two or three times a day. (24 October 1798) [ Image Omitted ] The art of letter writing Letter writing was part of Jane Austen’s typical morning routine, often undertaken before breakfast.

Manure is a key nutrient resource on smallholder farms in the tropics, especially on poorly buffered sandy soils, due to its multiple benefits for soil fertility. Farmers preferentially apply manure to fields closest to homesteads (homefields), which are more fertile than fields further away (outfields). A three-year experiment was established on homefields and outfields on sandy and clayey soils to assess the effects of mineral nitrogen (N) fertilizer application in combination with manure or mineral phosphorus (P) on maize yields and soil chemical properties. Significant maize responses to application of N and manure were observed on all fields except the depleted sandy outfield. Large amounts of manure (17 t ha-¹ year-¹) were required to significantly increase soil organic carbon (SOC), pH, available P, and base saturation, and restore productivity of the depleted sandy outfield. Sole N as ammonium nitrate (100 kg N ha-¹) or in combination with single superphosphate led to acidification of the sandy soils, with a decrease of up to 0.8 pH units after three seasons. In a greenhouse experiment, N and calcium (Ca) were identified as deficient in the sandy homefield, while N, P, Ca, and zinc (Zn) were deficient or low on the sandy outfield. The deficiencies of Ca and Zn were alleviated by the addition of manure. This study highlights the essential role of manure in sustaining and replenishing soil fertility on smallholder farms through its multiple effects, although it should be used in combination with N mineral fertilizers due to its low capacity to supply N.

Abstract Objectives The aim of this study is to evaluate the influence of ionizing radiotherapy on the resin-dentin interface in endodontically treated teeth restored with fiber posts using a dual-cure resin cement performed with the etch-and-rinse (ER) and self-etch (SE) approaches in terms of push-out bond strength (MPa), and to analyze the post/cement/dentin interface using scanning electron microscopy (SEM).Materials and methodsSeventy-six single-rooted human teeth were used and randomly assigned into two main groups (n = 38): one non-irradiated group (NoRad) and one group subjected to a cumulative radiation dose of 60 Gy (Rad). All root canals were instrumented and were further subdivided into two subgroups (n = 19) following the adhesive approach: ER (RadER; NoRadER) and SE (RadSE; NoRadSE) used for fiber post luting with the universal adhesive and dual cure resin cement. Each root was sectioned perpendicularly to its long axis and sections from the middle third of the roots were chosen for SEM analysis and push-out bond strength test. Two-way ANOVA with post hoc Tukey tests and a dummy variable linear regression analysis were used for data analysis.ResultsRegardless of the adhesive approach, push-out bond strength in irradiated teeth resulted in significantly lower values than non-irradiated teeth (p = 0.0001). There were no significant differences between the ER and SE approaches in non-irradiated teeth (p = 0.955), whereas the ER approach showed significantly higher bond strengths than the SE approach in irradiated teeth (p = 0.0001).ConclusionsIonizing radiotherapy resulted in dentin structure disruption and negatively affected the push-out bond strength of fiber posts to intraradicular dentin. The reduction in bond strength was also more significant with the SE approach than with the ER approach.Clinical relevanceThe alterations resulting from root dentin irradiation seem to influence adhesive systems bond strength to dentin, as these changes contribute to lower push-out bond strength in irradiated groups before fiber post luting. Thus, clinicians should prepare patients with a reasonable restorative treatment plan prior to radiotherapy and simultaneously initiate a preventive program during radiotherapy.

Variability of soil fertility within, and across farms, poses a major challenge for increasing crop productivity in smallholder systems of sub-Saharan Africa. This study assessed the effect of farmers' resource endowment and nutrient management strategies on variability in soil fertility and plant nutrient uptake between different fields in Gokwe South (ave. rainfall ~650 mm year⁻¹; 16.3 persons km⁻²) and Murewa (ave. rainfall ~850 mm year⁻¹; 44.1 persons km⁻²) districts, Zimbabwe. In Murewa, resource-endowed farmers applied manure (>3.5 t ha⁻¹ year⁻¹) on fields closest to their homesteads (homefields) and none to fields further away (outfields). In Gokwe the manure was not targeted to any particular field, and farmers quickly abandoned outfields and opened up new fields further way from the homestead once fertility had declined, but homefields were continually cultivated. Soil available P was higher in homefields (8-13 mg kg⁻¹) of resource-endowed farmers than on outfields and all fields on resource constrained farms (2-6 mg kg⁻¹) in Murewa. Soil fertility decreased with increasing distance from the homestead in Murewa while the reverse trend occurred in Gokwe South, indicating the impact of different soil fertility management strategies on spatial soil fertility gradients. In both districts, maize showed deficiency of N and P, implying that these were the most limiting nutrients. It was concluded that besides farmers' access to resources, the direction of soil fertility gradients also depends on agro-ecological conditions which influence resource management strategies.

The purpose of this study was to evaluate the general attitude of senior dental students towards rubber dam use, specifically focusing on endodontic practices prior to starting to serve community. Questionnaires were distributed to senior year students of a private school and a state school in Istanbul. Questions were asked about areas where the students used rubber dam, its advantages and difficulties, and whether they agreed or disagreed with some aspects of the rubber dam. The private school students rated isolation whereas those of the state school selected prevention of aspiration which the top advantage rubber dam provides. Students of the state school agreed with the opinion that isolation cannot be achieved without rubber dam and it extended the procedure with a significantly higher ratio compared to the private school. Within the limitations of the present study, it can be concluded that the perceptions of dental students on rubber dam needs to be improved and strategies should be developed so that this valuable adjunct will comprise one of the indispensable elements of dental care.

In 2005, the nutritional content of children's school lunches in England was widely criticised, leading to a major policy change in 2006. Food and nutrient-based standards were reintroduced requiring primary schools to comply by September 2008. We aimed to determine the effect of the policy on the nutritional content at lunchtime and in children's total diet. We undertook a natural experimental evaluation, analysing data from cross-sectional surveys in 12 primary schools in North East England, pre and post policy. Dietary data were collected on four consecutive days from children aged 4-7 years (n = 385 in 2003-4; n = 632 in 2008-9). We used linear mixed effect models to analyse the effects of gender, year, and lunch type on children's mean total daily intake. Both pre- and post-implementation, children who ate a school lunch consumed less sodium (mean change -128 mg, 95% CI: -183 to -73 mg) in their total diet than children eating home-packed lunches. Post-implementation, children eating school lunches consumed a lower % energy from fat (-1.8%, -2.8 to -0.9) and saturated fat (-1.0%; -1.6 to -0.5) than children eating packed lunches. Children eating school lunches post implementation consumed significantly more carbohydrate (16.4 g, 5.3 to 27.6), protein (3.6 g, 1.1 to 6.0), non-starch polysaccharides (1.5 g, 0.5 to 1.9), vitamin C (0.7 mg, 0.6 to 0.8), and folate (12.3 µg, 9.7 to 20.4) in their total diet than children eating packed lunches. Implementation of school food policy standards was associated with significant improvements in the nutritional content of school lunches; this was reflected in children's total diet. School food- and nutrient-based standards can play an important role in promoting dietary health and may contribute to tackling childhood obesity. Similar policy measures should be considered for other environments influencing children's diet.

This case report describes the tissue injury caused by inadvertently extruded NaOCl through the apical constriction. A 56-year-old female patient with complaints of pain, swelling, and ecchymosis on the left side of her face was referred to our clinic. The symptoms had emerged following root canal treatment of the maxillary left first premolar, and a soft tissue complication due to apical extrusion of NaOCl was diagnosed. Antibiotics and analgesics were prescribed. DVT images revealed that the buccal root apex had perforated the maxillary bone. The patient was followed up every other day and became asymptomatic on the 10th day. Endodontic therapy was completed with routine procedures. Determining working length precisely and following irrigation protocols meticulously are indispensable to prevent this type of complication. 3D visualization of the affected area may reveal the cause of the incident.

In September 2009, middle and secondary schools in England were required to comply with food and nutrient-based standards for school food. We examined the impact of this policy change on children's lunchtime and total dietary intake. We undertook repeat cross-sectional surveys in six Northumberland middle schools in 1999-2000 and 2009-10. Dietary data were collected from 11-12 y olds (n = 298 in 1999-2000; n = 215 in 2009-10). Children completed two consecutive 3-day food diaries, each followed by an interview. Linear mixed effect models examined the effect of year, lunch type and level of socio-economic deprivation on children's mean total dietary intake. We found both before and after the introduction of the food and nutrient-based standards children consuming a school lunch, had a lower per cent energy from saturated fat (-0.5%; p = 0.02), and a lower intake of sodium (-143 mg; p = 0.02), and calcium (-81 mg; p = 0.001) in their total diet, compared with children consuming a home-packed lunch. We found no evidence that lunch type was associated with mean energy, or absolute amounts of NSP, vitamin C and iron intake. There was marginal evidence of an association between lunch type and per cent energy NMES (p = 0.06). In 1999-2000, children consuming a school lunch had a higher per cent energy from fat in their total diet compared with children consuming a home-packed lunch (2.8%), whereas by 2009-10, they had slightly less (-0.2%) (year by lunch type interaction p<0.001; change in mean differences -3%). We found limited evidence of an impact of the school food and nutrient-based standards on total diet among 11-12 year olds. Such policies may need to be supported by additional measures, including guidance on individual food choice, and the development of wider supportive environments in school and beyond the school gates.

Smallholder farming systems in sub-Saharan Africa have undergone changes in land use, productivity and sustainability. Understanding of the drivers that have led to changes in land use in these systems and factors that influence the systems' sustainability is useful to guide appropriate targeting of intervention strategies for improvement. We studied low input Teso farming systems in eastern Uganda from 1960 to 2001 in a place-based analysis combined with a comparative analysis of similar low input systems in southern Mali. This study showed that policy-institutional factors next to population growth have driven land use changes in the Teso systems, and that nutrient balances of farm households are useful indicators to identify their sustainability. During the period of analysis, the fraction of land under cultivation increased from 46 to 78%, and communal grazing lands nearly completely disappeared. Cropping diversified over time; cassava overtook cotton and millet in importance, and rice emerged as an alternative cash crop. Impacts of political instability, such as the collapse of cotton marketing and land management institutions, of communal labour arrangements and aggravation of cattle rustling were linked to the changes. Crop productivity in the farming systems is poor and nutrient balances differed between farm types. Balances of N, P and K were all positive for larger farms (LF) that had more cattle and derived a larger proportion of their income from off-farm activities, whereas on the medium farms (MF), small farms with cattle (SF1) and without cattle (SF2) balances were mostly negative. Sustainability of the farming system is driven by livestock, crop production, labour and access to off-farm income. Building private public partnerships around market-oriented crops can be an entry point for encouraging investment in use of external nutrient inputs to boost productivity in such African farming systems. However, intervention strategies should recognise the diversity and heterogeneity between farms to ensure efficient use of these external inputs.