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Tonsillectomy is one of the most common otolaryngological procedures. Nonetheless, there is still no universally approved ‘gold standard’ technique.
To compare the safety and efficacy of argon plasma coagulation and coblation techniques in tonsillectomy.
A multi-institutional, retrospective cohort study was conducted, comprising 283 patients who underwent bilateral tonsillectomies performed by a single surgeon between 2014 and 2017. The outcome measures included: operative time, intra-operative blood loss, post-operative pain and post-operative haemorrhage.
In the argon plasma coagulation group, mean operative time and post-operative haemorrhage rate were significantly reduced, p = 0.0006 and p = 0.003 respectively. There was no statistically significant difference between the two groups in terms of post-operative pain and intra-operative blood loss.
The argon plasma coagulation technique is easy, safe and efficacious. Argon plasma coagulation tonsillectomy seems cost-effective compared to coblation tonsillectomy: the single-use disposable electrode tip and wand used in this study cost AUD$76.50 and AUD$380 respectively. Argon plasma coagulation appears to be a favourable alternative to current modalities such as coblation.
Queues are part of everyday routine and experienced by most shoppers, yet little attention has been given to providing historical accounts of queuing as a consumer task or as a shopper experience. This paper examines grocery shop queues and the changing experience of shoppers in historical perspective, specifically focusing upon the shift from counter-service to self-service grocery formats in Britain from 1945 to 1975. The paper draws upon a wide range of material using evidence from oral histories and witness groups, which is supported by contemporary sources from the Mass Observation Archive, newspapers, shopper surveys, and trade publications and reports. The conceptual framework developed in the paper explores the public and private dimensions of queues to consider the experiences and perceptions of shoppers during a period of rapid change in the retail grocery system. More generally, the paper contributes to our understanding of how management innovations are connected to untraded public values.
By soaking formalinized rat-tail tendons in 2 M resorcinol, the tendon lattice is expanded equatorially from an interplanar spacing of 11.7 Å to 14.5 Å, indicating a diameter of 7.2 Å for the spiral core of collagen. Resorcinol distorts the lattice of nylon (6:6), converting the normal triclinic cell to an orthorhombic cell whose a and b axes are approximately four times those of the original nylon and whose c axis is reduced from 17.2 to 16.5 Å.
Soldier operational performance is determined by their fitness, nutritional status, quality of rest/recovery, and remaining injury/illness free. Understanding large fluctuations in nutritional status during operations is critical to safeguarding health and well-being. There are limited data world-wide describing the effect of extreme climate change on nutrient profiles. This study investigated the effect of hot-dry deployments on vitamin D status (assessed from 25-hydroxyvitamin D (25(OH)D) concentration) of young, male, military volunteers. Two data sets are presented (pilot study, n 37; main study, n 98), examining serum 25(OH)D concentrations before and during 6-month summer operational deployments to Afghanistan (March to October/November). Body mass, percentage of body fat, dietary intake and serum 25(OH)D concentrations were measured. In addition, parathyroid hormone (PTH), adjusted Ca and albumin concentrations were measured in the main study to better understand 25(OH)D fluctuations. Body mass and fat mass (FM) losses were greater for early (pre- to mid-) deployment compared with late (mid- to post-) deployment (P<0·05). Dietary intake was well-maintained despite high rates of energy expenditure. A pronounced increase in 25(OH)D was observed between pre- (March) and mid-deployment (June) (pilot study: 51 (sd 20) v. 212 (sd 85) nmol/l, P<0·05; main study: 55 (sd 22) v. 167 (sd 71) nmol/l, P<0·05) and remained elevated post-deployment (October/November). In contrast, PTH was highest pre-deployment, decreasing thereafter (main study: 4·45 (sd 2·20) v. 3·79 (sd 1·50) pmol/l, P<0·05). The typical seasonal cycling of vitamin D appeared exaggerated in this active male population undertaking an arduous summer deployment. Further research is warranted, where such large seasonal vitamin D fluctuations may be detrimental to bone health in the longer-term.
Dissociation between caloric and head impulse test results in patients with vestibular disorders has been well documented since the introduction of video head impulse testing. Prior to the introduction of video head impulse testing, vestibular diagnostic services relied mainly on caloric testing, and it is now known that the caloric testing shows more positive results than video head impulse testing. A dissipation model was proposed to explain this dissociation.
This paper presents two cases in which caloric testing indicated an absent or significantly reduced response on the horizontal semicircular canal plane but video head impulse testing showed near-normal or normal vestibulo-ocular reflex gain on the same plane.
This report supports the dissipation theory and questions the functional relevance of canal paresis values calculated from caloric test results.
Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held across the United States between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide resistance management. The major goals of the sessions were to gain an understanding of stakeholders and their goals and concerns related to herbicide resistance management, to become familiar with regional differences, and to identify decision maker needs to address herbicide resistance. The messages shared by listening-session participants could be summarized by six themes: we need new herbicides; there is no need for more regulation; there is a need for more education, especially for others who were not present; diversity is hard; the agricultural economy makes it difficult to make changes; and we are aware of herbicide resistance but are managing it. The authors concluded that more work is needed to bring a community-wide, interdisciplinary approach to understanding the complexity of managing weeds within the context of the whole farm operation and for communicating the need to address herbicide resistance.
Seven half-day regional listening sessions were held between December 2016 and April 2017 with groups of diverse stakeholders on the issues and potential solutions for herbicide-resistance management. The objective of the listening sessions was to connect with stakeholders and hear their challenges and recommendations for addressing herbicide resistance. The coordinating team hired Strategic Conservation Solutions, LLC, to facilitate all the sessions. They and the coordinating team used in-person meetings, teleconferences, and email to communicate and coordinate the activities leading up to each regional listening session. The agenda was the same across all sessions and included small-group discussions followed by reporting to the full group for discussion. The planning process was the same across all the sessions, although the selection of venue, time of day, and stakeholder participants differed to accommodate the differences among regions. The listening-session format required a great deal of work and flexibility on the part of the coordinating team and regional coordinators. Overall, the participant evaluations from the sessions were positive, with participants expressing appreciation that they were asked for their thoughts on the subject of herbicide resistance. This paper details the methods and processes used to conduct these regional listening sessions and provides an assessment of the strengths and limitations of those processes.
Herbicide resistance, and in particular multiple-herbicide resistance, poses an ever-increasing threat to food security. A biotype of junglerice [Echinochloa colona (L.) Link] with resistance to four herbicides, imazamox, fenoxaprop-P-ethyl, quinclorac, and propanil, each representing a different mechanism of action, was identified in Sunflower County, MS. Dose responses were performed on the resistant biotype and a biotype sensitive to all four herbicides to determine the level of resistance. Application of a cytochrome P450 inhibitor, malathion, with the herbicides imazamox and quinclorac resulted in increased susceptibility in the resistant biotype. Differential gene expression analysis of resistant and sensitive plants revealed that 170 transcripts were upregulated in resistant plants relative to sensitive plants and 160 transcripts were upregulated in sensitive plants. In addition, 507 transcripts were only expressed in resistant plants and 562 only in sensitive plants. A subset of these transcripts were investigated further using quantitative PCR (qPCR) to compare gene expression in resistant plants with expression in additional sensitive biotypes. The qPCR analysis identified two transcripts, a kinase and a glutathione S-transferase that were significantly upregulated in resistant plants compared with the sensitive plants. A third transcript, encoding an F-box protein, was downregulated in the resistant plants relative to the sensitive plants. As no cytochrome P450s were differentially expressed between the resistant and sensitive plants, a single-nucleotide polymorphism analysis was performed, revealing several nonsynonymous point mutations of interest. These candidate genes will require further study to elucidate the resistance mechanisms present in the resistant biotype.
Childhood adversity (CA) is known to predict sensitization to proximal stressors. Researchers have suggested that disruptions in hypothalamus–pituitary–adrenal axis functioning may be a biological mechanism. If so, CA may predict altered associations between proximal life stress and markers of cortisol secretion. We examined whether CA moderates associations between recent episodic stress and (a) the cortisol awakening response (CAR), and (b) depressive symptoms, in 241 adolescents aged 14–17 years (cortisol n = 196). Salivary cortisol was sampled at 0, 30, and 60 min postawakening for 2 days. The CAR was calculated as the area under the curve with respect to increase and waking cortisol. CA and episodic stress were assessed using contextual-threat-method-coded objective interviews. CA significantly interacted with episodic stress to predict both the CAR and depression. Among those with low CA, episodic stress predicted increased CAR but did not predict depression. For adolescents with high CA, episodic stress predicted lower CAR and higher depression. These interactions were found only for independent (uncontrollable, fateful) events, and not for dependent (self-generated) stress. Increased allostatic load resulting from CA exposure may interfere with adolescents' ability to optimally regulate their CAR in relation to recent stress, contributing to increased depression risk.
Acute mastoiditis remains the commonest intratemporal complication of otitis media in the paediatric population. There has been a lack of consensus regarding the diagnosis and management of acute mastoiditis, resulting in considerable disparity in conservative and surgical management.
To review the current literature, proposing recommendations for the management of paediatric acute mastoiditis and appraising the treatment outcomes.
A systematic review was conducted using PubMed, Web of Science and Cochrane Library databases.
Twenty-one studies were included, with a total of 564 patients. Cure rates of medical treatment, conservative surgery and mastoidectomy were 95.9 per cent, 96.3 per cent and 89.1 per cent, respectively.
Mastoidectomy may be the most definitive treatment available; however, reviewed data suggest that conservative treatment alone has high efficacy as first-line treatment in uncomplicated cases of acute mastoiditis, and conservative therapy may be an appropriate first-line management when treating acute mastoiditis.
An evolution of the low-frequency pulse profile of PSR B2217+47 is observed during a six-year observing campaign with the LOFAR telescope at 150 MHz. The evolution is manifested as a new component in the profile trailing the main peak. The leading part of the profile, including a newly-observed weak component, is steady during the campaign. The transient component is not visible in simultaneous observations at 1500 MHz using the Lovell telescope, implying a chromatic effect. A variation in the dispersion measure of the source is detected in the same timespan. Precession of the pulsar and changes in the magnetosphere are investigated to explain the profile evolution. However, the listed properties favour a model based on turbulence in the interstellar medium (ISM). This interpretation is confirmed by a strong correlation between the intensity of the transient component and main peak in single pulses. Since PSR B2217+47 is the fourth brightest pulsar visible to LOFAR, we speculate that ISM-induced pulse profile evolution might be relatively common but subtle and that SKA-Low will detect many similar examples. In this scenario, similar studies of pulse profile evolution could be used in parallel with scintillation arcs to characterize the properties of the ISM.
The recent revelation that there are correlated period derivative and pulse shape changes in pulsars has dramatically changed our understanding of timing noise as well as the relationship between the radio emission and the properties of the magnetosphere as a whole. Using Gaussian processes we are able to model timing and emission variability using a regression technique that imposes no functional form on the data. We revisit the pulsars first studied by Lyne et al. (2010). We not only confirm the emission and rotational transitions revealed therein, but reveal further transitions and periodicities in 8 years of extended monitoring. We also show that in many of these objects the pulse profile transitions between two well-defined shapes, coincident with changes to the period derivative. With a view to the SKA and other telescopes capable of higher cadence we also study the detection limitations of period derivative changes.
CCDs make the near-infrared spectral region out to about 1.1 μ observable. A good deal of information on the spectra of AGNs in this range has been published, which we are trying to systematize and extend at Lick. Our original lens-grism spectrograph camera is opaque over the region λ8600-λ10250, no doubt as a result of a coating on one of the elements of the Nikon lens, making this program impossible with it. However our newer “UV-Schmidt” camera is quite effective in this region. With it we have obtained well exposed spectra at moderate resolution (FWHM ≈ 7 Å) of NGC 4151 in three overlapping segments covering the region 7000–11000 Å. Also, for comparison we obtained similar spectra of NGC 1976, the Orion Nebula. The wavelengths and relative line fluxes were measured, and most of the lines were identified. The strongest three lines in both objects are, in order, [S III] λ9532, He I λ10830, and [S III] λ9069. The Orion Nebula spectrum is very helpful for identifying lines in NGC 4151, and for comparison with it. Among the lines identified in NGC 1976, many of them previously known, are [O II], [S II], [Ar III], [Fe II], [Ni II], [Ni III], [Cl II], [C I], in addition to O I λ8446, many H I Paschen lines and He I.
In a recent essay, Harker and coauthors stated that considering herbicide resistance as a wicked problem “without clear causes or solutions” ignores what weed scientists know about the biology and management of herbicide-resistant weeds. In this response, we argue that this misrepresents what is meant by “wicked” and that the wicked problem concept is valuable in understanding the multifaceted nature of herbicide resistance as a human-caused phenomenon.
Unusual speleothems, associated with hyperalkaline (pH > 12) groundwaters
have formed within a shallow, abandoned railway tunnel at Peak Dale,
Derbyshire, UK. The hyperalkaline groundwaters are produced by the leaching
of a thin layer (<2 m) of old lime-kiln waste on the soil-bedrock surface
above the tunnel by rainwater. This results in a different reaction and
chemical process to that more commonly associated with the formation of
calcium carbonate speleothems from Ca-HCO3-type groundwaters and
degassing of CO2. Stalagmites within the Peak Daletunnel have
grown rapidly (averaging 33 mm y–1), following the closure of the
tunnel 70 years ago. They have an unusual morphology comprising a central
sub-horizontally-laminated column of micro- to nano-crystalline calcium
carbonate encompassed by an outer sub-vertical assymetricripple-laminated
layer. The stalagmites are composed largely of secondary calcite forming
pseudomorphs (<1 mm) that we believe to be predominantly after the 'cold
climate' calcium carbonate polymorph, ikaite (calcium carbonate hexahydrate:
CaCO3·6H2O), withminor volumes of small (<5 μm)
pseudomorphs after vaterite. The tunnel has a near constant temperature of
8–9°C, which is slightly above the previously published crystallization
temperatures for ikaite (<6°C). Analysis of a stalagmite actively growing
at the time ofsampling, and preserved immediately within a dry nitrogen
cryogenic vessel, indicates that following crystallization of ikaite,
decomposition to calcite occurs rapidly, if not instantaneously. We believe
this is the first occurrence of this calcium carbonate polymorph observed
Although high dose n-3 PUFA supplementation reduces exercise- and hyperpnoea-induced bronchoconstriction (EIB/HIB), there are concurrent issues with cost, compliance and gastrointestinal discomfort. It is thus pertinent to establish the efficacy of lower n-3 PUFA doses. Eight male adults with asthma and HIB and eight controls without asthma were randomly supplemented with two n-3 PUFA doses (6·2 g/d (3·7 g EPA and 2·5 g DHA) and 3·1 g/d (1·8 g EPA and 1·3 g DHA)) and a placebo, each for 21 d followed by 14 d washout. A eucapnic voluntary hyperpnoea (EVH) challenge was performed before and after treatments. Outcome measures remained unchanged in the control group. In the HIB group, the peak fall in forced expiratory volume in 1 s (FEV1) after EVH at day 0 (−1005 (sd 520) ml, −30 (sd 18) %) was unchanged after placebo. The peak fall in FEV1 was similarly reduced from day 0 to day 21 of 6·2 g/d n-3 PUFA (−1000 (sd 460) ml, −29 (sd 17) % v. −690 (sd 460) ml, −20 (sd 15) %) and 3·1 g/d n-3 PUFA (−970 (sd 480) ml, −28 (sd 18) % v. −700 (sd 420) ml, −21 (sd 15) %) (P<0·001). Baseline fraction of exhaled nitric oxide was reduced by 24 % (P=0·020) and 31 % (P=0·018) after 6·2 and 3·1 g/d n-3 PUFA, respectively. Peak increases in 9α, 11β PGF2 after EVH were reduced by 65 % (P=0·009) and 56 % (P=0·041) after 6·2 and 3·1 g/d n-3 PUFA, respectively. In conclusion, 3·1 g/d n-3 PUFA supplementation attenuated HIB and markers of airway inflammation to a similar extent as a higher dose. Lower doses of n-3 PUFA thus represent a potentially beneficial adjunct treatment for adults with asthma and EIB.
Castor is an industrially important oilseed crop. Vascular wilt caused by the soil borne fungus Fusarium oxysporum f. sp. ricini is a serious disease of castor. Use of resistant cultivars is the only viable option for management of wilt disease problem in castor production. Excellent sources of resistance to wilt have been found in castor germplasm. In this study, a set of four castor inbred lines (48–1, CI-1, AP42 and AP48) was characterized for inheritance of resistance to wilt by studying segregating populations generated by crossing these inbred lines with eight different susceptible genotypes. An artificial screening method (sick pot) with a new scoring system (days to wilt) was used for evaluation of plant progenies for reaction to the pathogen infection. The reaction of F1s indicated that the nature of resistance in 48–1, CI-1 and AP48 is recessive whereas it was dominant in AP42. Inheritance results from eight F2 populations showed that resistance to wilt is conferred by a single locus in one population and at least two loci, which interact in complementary way, in other seven populations. Different modes of inheritance were also observed when the same resistant source was crossed with different susceptible parents, indicating the possible role of genetic backgrounds in determining resistance. Overall, the results suggested that Mendelian resistance to wilt is predominant in the castor genotypes, which can be exploited for breeding cultivars. Particularly, AP42 with dominant nature of resistance will be of great interest to hybrid breeding.
Contemporary processes of moraine development at the margins of polar glaciers encompass a wide range of subtly different mechanisms. Two types of “controlled” moraine evolution, applicable to hummocks and transverse moraine ridges, are identified from Wright Lower Glacier and Webb Glacier, southern Victoria Land, Antarctica. Type 1 moraine complexes involve a relatively abundant supply of supraglacial debris, the development of transverse thrust blocks in the ablation-zone ice and the subsequent re-arrangement of ablation debris in ablation cusps and on inactive thrust blocks. Relict landform suites, apparently formed in this manner, reveal large coarse-grained hummocks inset behind moraine ridge remnants.
Type 2 moraines may develop where the supply of supraglacial debris is meagre but the growth of ablation cusps concentrates primarily englacial debris into small irregular hummocks. The gravel component of this debris is usually of finer texture than for type 1 deposits, reflecting abrasion/attrition effects of prior englacial transportation. Transverse moraine ridges may or may not be associated with type 2 hummocks, depending on local variations of ice motion, ice decay, and debris supply.
The interaction of Stokes’ edge waves with a developing near-shore ice zone is examined from two points of view. First, the effect of a well-fragmented ice suspension on the classical Stokes’ edge wave is discussed. Secondly, the possibility that ice-cusp formation (and, thereafter, ice mounds or volcanoes) can be initiated by edge waves is examined. Results indicate a negligible effect of a well-fragmented floating ice field on the Stokes’ dispersion equation for typical wave periods, but do indicate that the presence of a standing Stokes’ edge wave may lead to the initiation of ice-field cusps as ice formation occurs in the near-shore zone.