A photo-elicitation exploration of UK mothers' experiences of extended breastfeeding.

In this qualitative study we explored the experiences of women breastfeeding children over 12 months of age. Data were collected from 24 participants using semi-structured photo-elicitation interviews and photo-prompted online surveys. Participants took photographs of their extended breastfeeding experiences over one week and reflected on how the events depicted made them feel, and what they represented in terms of their experience. Data were analysed using Interpretative Phenomenological Analysis. Four themes were developed; parenting through breastfeeding: meeting the needs of my child, my body is not my own, social influences on the breastfeeding experience, and thinking about stopping: my choice or theirs? Findings highlight that extended breastfeeding was experienced as beneficial for both mother and child, promoting closeness, and bonding, and providing a valued parenting tool. However, some mothers reported conflict between their desire for child-led extended breastfeeding and the need to regain autonomy and control of their own bodies. The dangers of negative societal responses to extended breastfeeding and risks to mental health posed by cultural constructions of 'ideal' motherhood are discussed.

Drinking frequency effects on the performance of cattle: a systematic review.

This study used a systematic literature review methodology to determine whether there is evidence that drinking frequency has effects on cattle performance, what performance responses to drinking frequency are documented and how performance responses vary according to environmental and animal factors. Electronic databases were searched for English language articles with original data on at least one performance attribute (e.g. water intake, feed intake, live weight) of cattle in response to voluntary drinking frequency or controlled access periods to water. Sixteen experiments on dairy cows and 12 experiments on beef cattle were retrieved from the literature. For beef cattle, all experiments reported reduced water and feed intake with access to water once every second and/or third day compared with once-daily access. Median reductions of 15% and 25% in water intake and 16% and 9% in feed intake were found across experiments respectively. Live weight responses of beef cattle to access to water were limited and yielded positive, negative and no effects. For dairy cows, most experiments reported reduced water intake, milk yield and milk fat content with access to water twice or once daily compared with controls (ad libitum or ad libitum except at the dairy). Median reductions of 13% and 12% in water intake, 2% and 1% in milk yield and 1% and 2% in milk fat content were found across experiments respectively. Water availability effects on feed intake and live weight were very limited for dairy cows and yielded positive, neutral and negative effects. Season, climate, experiment conditions, animal class and animal genotype were identified to potentially influence intake responses of cattle. The review highlights a number of important gaps in the literature where future work is required to better understand the optimum drinking frequency of cattle and implications of water availability on health, welfare and performance.

The dual-acting chemotherapeutic agent Alchemix induces cell death independently of ATM and p53.

Topoisomerase inhibitors are in common use as chemotherapeutic agents although they can display reduced efficacy in chemotherapy-resistant tumours, which have inactivated DNA damage response (DDR) genes, such as ATM and TP53. Here, we characterise the cellular response to the dual-acting agent, Alchemix (ALX), which is a modified anthraquinone that functions as a topoisomerase inhibitor as well as an alkylating agent. We show that ALX induces a robust DDR at nano-molar concentrations and this is mediated primarily through ATR- and DNA-PK- but not ATM-dependent pathways, despite DNA double strand breaks being generated after prolonged exposure to the drug. Interestingly, exposure of epithelial tumour cell lines to ALX in vitro resulted in potent activation of the G2/M checkpoint, which after a prolonged arrest, was bypassed allowing cells to progress into mitosis where they ultimately died by mitotic catastrophe. We also observed effective killing of lymphoid tumour cell lines in vitro following exposure to ALX, although, in contrast, this tended to occur via activation of a p53-independent apoptotic pathway. Lastly, we validate the effectiveness of ALX as a chemotherapeutic agent in vivo by demonstrating its ability to cause a significant reduction in tumour cell growth, irrespective of TP53 status, using a mouse leukaemia xenograft model. Taken together, these data demonstrate that ALX, through its dual action as an alkylating agent and topoisomerase inhibitor, represents a novel anti-cancer agent that could be potentially used clinically to treat refractory or relapsed tumours, particularly those harbouring mutations in DDR genes.

Custom-made titanium cranioplasty: early and late complications of 151 cranioplasties and review of the literature.

A diverse range of techniques is available for reconstruction of full-thickness calvarial defects and the optimum substrate for cranioplasty remains unproven. During a 9-year period, 149 patients underwent insertion of 151 custom-made titanium cranioplasties using the same technique. Data relating to patient demographics, indication for cranioplasty, and site and size of the defect were collected from the clinical records. Patients were followed up in all cases for a mean of 1 year 2 months (range 7 days to 8 years 8 months). Early complications requiring intervention were experienced in 7% and included seroma, haematoma, and continued bleeding necessitating implant removal in one patient. One death occurred at 3 days post-operation due to haemorrhagic stroke. Late self-limiting complications such as seroma were experienced in 19% of patients, however complete failure requiring implant removal was seen in only 4% of cases. Infection was the cause of failure in all cases. A comprehensive literature review was carried out and data abstracted to compare reported failure rates in other techniques of full-thickness cranial reconstruction. This review shows that custom-made patient-specific titanium cranioplasties compare very favourably to the other published techniques and remain a tried and tested option for reconstruction of all sizes of full-thickness calvarial defect.

Mass spectral analysis of organic aerosol formed downwind of the Deepwater Horizon oil spill: field studies and laboratory confirmations.

In June 2010, the NOAA WP-3D aircraft conducted two survey flights around the Deepwater Horizon (DWH) oil spill. The Gulf oil spill resulted in an isolated source of secondary organic aerosol (SOA) precursors in a relatively clean environment. Measurements of aerosol composition and volatile organic species (VOCs) indicated formation of SOA from intermediate-volatility organic compounds (IVOCs) downwind of the oil spill (Science2011, 331, doi 10.1126/science.1200320). In an effort to better understand formation of SOA in this environment, we present mass spectral characteristics of SOA in the Gulf and of SOA formed in the laboratory from evaporated light crude oil. Compared to urban primary organic aerosol, high-mass-resolution analysis of the background-subtracted SOA spectra in the Gulf (for short, "Gulf SOA") showed higher contribution of C(x)H(y)O(+) relative to C(x)H(y)(+) fragments at the same nominal mass. In each transect downwind of the DWH spill site, a gradient in the degree of oxidation of the Gulf SOA was observed: more oxidized SOA (oxygen/carbon = O/C ∼0.4) was observed in the area impacted by fresher oil; less oxidized SOA (O/C ∼0.3), with contribution from fragments with a hydrocarbon backbone, was found in a broader region of more-aged surface oil. Furthermore, in the plumes originating from the more-aged oil, contribution of oxygenated fragments to SOA decreased with downwind distance. Despite differences between experimental conditions in the laboratory and the ambient environment, mass spectra of SOA formed from gas-phase oxidation of crude oil by OH radicals in a smog chamber and a flow tube reactor strongly resembled the mass spectra of Gulf SOA (r(2) > 0.94). Processes that led to the observed Gulf SOA characteristics are also likely to occur in polluted regions where VOCs and IVOCs are coemitted.

Amaurosis, ophthalmoplegia, ptosis, mydriasis and periorbital blanching following inferior alveolar nerve anaesthesia.

BACKGROUND: Ophthalmic complications following inferior alveolar nerve anaesthesia are rare. They include transient blindness (amaurosis), ophthalmoplegia, ptosis, mydriasis and diplopia. These events may occur following the intravascular administration of anaesthetic solution and are distressing to both patient and operator alike. CASE REPORT: We report the unusual case of a young patient who experienced amaurosis, total ophthalmoplegia, complete upper eyelid ptosis, mydriasis and periorbital blanching following inferior alveolar nerve anaesthesia. Similar but less profound signs were observed in the same patient on a subsequent occasion. This was following general anaesthesia, during which she had received local anaesthetic prior to mandibular wisdom tooth removal. CONCLUSIONS: Ophthalmic complications following inferior alveolar nerve anaesthesia are rare but distressing events. In particular, amaurosis is an extremely rare event and usually heralds a more sinister pathology such as stroke. Clinicians should be aware of these complications to minimise anxiety and reassure their patients appropriately.

Is coronal restoration more important than root filling for ultimate endodontic success?

The importance of a good coronal seal and restoration of the endodontically treated tooth has been hotly debated over recent years. This article reviews the evidence in the literature that exists to demonstrate which techniques can be used for optimal results, and whether the root filling or coronal seal is more relevant.

Woven polydioxanone biodegradable stents: a new treatment option for benign and malignant oesophageal strictures.

BACKGROUND: We present our initial experience with a new biodegradable (BD) esophageal stent in two patients, one for a therapy-resistant benign esophageal stricture, and the other as a temporary measure during curative radiotherapy for oesophageal carcinoma. METHODS: The BD stents need to be loaded into a conventional pull-back delivery system but are then placed in a standard fashion. Pre-dilatation should be avoided to reduce the risk of migration, however if migration occurs the stents can be left to dissolve in the stomach. The stents are radiolucent but easily identified on CT with minimal artefact and thus might even aid with radiotherapy planning. RESULTS: BD stents offer an exciting new strategy for therapy-resistant benign strictures as well as a supportive measure for oesophageal cancer undergoing non-surgical treatment.

Clinical correlates of cerebral white matter hyperintensities in cognitively normal older adults.

Many research studies have demonstrated asymptomatic white matter hyperintensities (WMHs) in older adults, which are postulated to be ischemic in origin. We hypothesized that certain clinical predictors, measured in a population of healthy older adults, would have a positive relationship with WMH scoring on magnetic resonance imaging (MRI). As part of a longitudinal study of cognitive aging we have performed MRI on healthy older adults. In a group of 46 volunteers (25 females; median age 73, range 63-84 years), we have calculated of the Hachinski score and Framingham Stroke Risk Profile (FSRP). Volunteers also provided self-reported health information using the Cornell Medical Index (CMI). These were compared against the total Age Related White Matter Changes (ARWMC) score. The mean total ARWMC score was 7.4 + or - 5.27 (+ or - S.D.) and only 3 (6.5%) individuals had no evidence of WMH. Regression analysis of individual variables identified self-report of cardiovascular disease from the CMI, section C as the only significant predictor of ARWMC. A multivariate linear regression model also identified FSRP at 1 year as a second independently significant predictor. The multivariate model accounted for 19% of the variance in total ARWMC score. The only 6.5% of individuals who had no WMH is in keeping with previous studies. The important finding was the positive relationship with self-reported cardiovascular disease, which is a possible biomarker of sub-clinical cerebrovascular disease (CVD).

Radiological balloon dilatation of post-treatment benign pharyngeal strictures.

AIMS: To assess the technical success, clinical outcomes and complications of radiologically guided balloon dilatation of benign strictures developing after treatment for head and neck cancer. MATERIALS AND METHODS: Forty-six balloon dilatations were performed in 20 patients. All dilatations were performed over a guidewire. RESULTS: Technical success was 100 per cent. Fifteen of the 20 patients demonstrated clinical improvement in dysphagia scores. Improvement in dysphagia was temporary in all patients (median 102 days), with multiple dilatations usually required (total dilatations ranged from one to seven). Immediate complications were encountered in six of the 46 (13 per cent) dilatations and were all minor. Late complications occurred after two procedures (4 per cent): localised perforation (later complicated by secondary infection) and recurrence of a previous, small, pharyngo-cutaneous fistula. CONCLUSION: Radiologically guided balloon dilatation is straightforward to perform and is well tolerated, but there is a small risk of perforation. Relief of symptoms is likely to be temporary, requiring multiple subsequent dilatations. A minority of patients will obtain no symptomatic relief.

Chemical and microphysical characterization of ambient aerosols with the aerodyne aerosol mass spectrometer.

The application of mass spectrometric techniques to the real-time measurement and characterization of aerosols represents a significant advance in the field of atmospheric science. This review focuses on the aerosol mass spectrometer (AMS), an instrument designed and developed at Aerodyne Research, Inc. (ARI) that is the most widely used thermal vaporization AMS. The AMS uses aerodynamic lens inlet technology together with thermal vaporization and electron-impact mass spectrometry to measure the real-time non-refractory (NR) chemical speciation and mass loading as a function of particle size of fine aerosol particles with aerodynamic diameters between approximately 50 and 1,000 nm. The original AMS utilizes a quadrupole mass spectrometer (Q) with electron impact (EI) ionization and produces ensemble average data of particle properties. Later versions employ time-of-flight (ToF) mass spectrometers and can produce full mass spectral data for single particles. This manuscript presents a detailed discussion of the strengths and limitations of the AMS measurement approach and reviews how the measurements are used to characterize particle properties. Results from selected laboratory experiments and field measurement campaigns are also presented to highlight the different applications of this instrument. Recent instrumental developments, such as the incorporation of softer ionization techniques (vacuum ultraviolet (VUV) photo-ionization, Li+ ion, and electron attachment) and high-resolution ToF mass spectrometers, that yield more detailed information about the organic aerosol component are also described.

Uptake of organic gas phase species by 1-methylnaphthalene.

Organic compounds are a significant component of tropospheric aerosols. In the present study, 1-methylnaphthalene was selected as a surrogate for aromatic hydrocarbons (PAHs) found in tropospheric aerosols. Mass accommodation coefficients (alpha) on 1-methylnaphthalene were determined as a function of temperature (267 K to 298 K) for gas-phase m-xylene, ethylbenzene, butylbenzene, alpha-pinene, gamma-terpinene, p-cymene, and 2-methyl-2-hexanol. The gas uptake studies were performed with droplets maintained under liquid-vapor equilibrium conditions using a droplet train flow reactor. The mass accommodation coefficients for all of the molecules studied in these experiments exhibit negative temperature dependence. The upper and lower values of alpha at 267 and 298 K respectively are as follows: for m-xylene 0.44 +/- 0.05 and 0.26 +/- 0.03; for ethylbenzene 0.37 +/- 0.03 and 0.22 +/- 0.04; for butylbenzene 0.47 +/- 0.06 and 0.31 +/- 0.04; for alpha-pinene 0.47 +/- 0.07 and 0.10 +/- 0.05; for gamma-terpinene 0.37 +/- 0.04 and 0.12 +/- 0.06; for p-cymene 0.74 +/- 0.05 and 0.36 +/- 0.07; for 2-methyl-2-hexanol 0.44 +/- 0.06 and 0.29 +/- 0.06. The uptake measurements also yielded values for the product HD(l)(1/2) for most of the molecules studied (H = Henry's law constant, D(l) = liquid-phase diffusion coefficient). Using calculated values of D(l), the Henry's law constants (H) for these molecules were obtained as a function of temperature. The H values at 298 K in units 10(3) M atm(-1) are as follows: for m-xylene (0.48 +/- 0.05); for ethylbenzene (0.50 +/- 0.08); for butylbenzene (3.99 +/- 0.93); for alpha-pinene (0.53 +/- 0.07); for p-cymene (0.23 +/- 0.07); for 2-methyl-2-hexanol (1.85 +/- 0.29).

Reversible posterior leukoencephalopathy syndrome associated with left ventricular assist device.

Reversible posterior leukoencephalopathy syndrome (RPLES), previously known as posterior reversible encephalopathy syndrome (PRES), is characterized by the presence of bilateral lesions located within the posterior border zones of the cerebral hemisphere and cerebellum. This condition commonly presents with headache, nausea, vomiting, decreased vision and level of consciousness, and seizures. RPLES has been associated with hypertensive encephalopathy, eclampsia, renal failure, and immunosuppressive therapy following transplant. We report the development of RPLES in a boy following implantation of a left ventricular assist device (LVAD). To our knowledge, this is the first report of RPLES in association with the use of LVAD.

A physiologically based biokinetic model for cesium in the human body.

A physiologically descriptive model of the biological behavior of cesium in the human body has been constructed around a detailed blood flow model. The rate of transfer from plasma into a tissue is determined by the blood perfusion rate and the tissue-specific extraction fraction of Cs during passage from arterial to venous plasma. Information on tissue-specific extraction of Cs is supplemented with information on the Cs analogues, K and Rb, and known patterns of discrimination between these metals by tissues. The rate of return from a tissue to plasma is estimated from the relative contents of Cs in plasma and the tissue at equilibrium as estimated from environmental studies. Transfers of Cs other than exchange between plasma and tissues (e.g. secretions into the gastrointestinal tract) are based on a combination of physiological considerations and empirical data on Cs or related elements. Model predictions are consistent with the sizable database on the time-dependent distribution and retention of radiocesium in the human body.

Role of duration and interval in perception of force pulses.

Three experiments investigated the perceptual threshold for a pulsed force stimulation of the middle phalanx of the forefinger. The first experiment (N = 5) manipulated duration of the pulse, and the second (N = 6) manipulated the interval between pulses. Both experiments held magnitude constant. The results confirmed high reliability and indicated that perceptual threshold decreased as both Duration and Interval increased. Although subjects responded consistently, they described the sensation as "muscular" and "diffuse." Exp. 3 (N = 12) covaried Duration and Interval and found effects similar to those of the first two studies. Also, Duration and Interval were independent. Additional research is needed to clarify the relations of duration, interval, and magnitude in contributing to conscious perception of the presence of applied force. Treating pulse magnitude as a dynamic variable by varying its rate of change within a train of force pulses could further our understanding of how perception of force changes depend upon rate.

Knowledge of results, movement type, and sex in coincidence timing.

The experiment tested 24 subjects (12 men and 12 women) on a Bassin anticipation timing task with a light stimulus velocity of 3 mph. The first aim was to compare the effects of three different types of movement responses, a simple key press with a finger, an arm movement to a key press, and a whole-body movement culminating with a kick to strike a target. The expectation that sensorimotor integra tion of the movement responses would be reflected in the accuracy and consistency of anticipation timing was supported by the results which showed that the key-press task was superior to either the arm or whole-body movement responses. This finding emphasises the role movement variables have in defining situational constraints and indicate that proficiency in coincidence anticipation appears to be influenced by the planning and organisation required for movement execution. The second aim was to examine the question of whether verbal knowledge of results was redundant. Analysis showed that verbal knowledge of results was redundant under all movement conditions. Further research is needed to identify conditions in which the visual system does not provide the motor control system with adequate information for appropriate execution of movement. An evaluation of sex differences in performance and learning comprised the third aim. That men were significantly more accurate and more consistent was in accord with previous evidence. Women might have a more conservative approach to responding than men. Effects of repeated practice, an inherent part of these studies, supported the principle that effective learning accrues from repeatedly solving the coincidence-timing problem. It was concluded that further investigation of movement variables is needed to develop understanding of how they are coupled with perceptual variables in coincidence-timing contexts.

Orientation, scale, and discontinuity as emergent properties of illusory contour shape.

A recent neural model of illusory contour formation is based on a distribution of natural shapes traced by particles moving with constant speed in directions given by Brownian motions. The input to that model consists of pairs of position and direction constraints, and the output consists of the distribution of contours joining all such pairs. In general, these contours will not be closed, and their distribution will not be scale-invariant. In this article, we show how to compute a scale-invariant distribution of closed contours given position constraints alone and use this result to explain a well-known illusory contour effect.