Easy data, hard data : the politics and pragmatics of Twitter research after the computational turn

In this chapter, we draw out the relevant themes from a range of critical scholarship from the small body of digital media and software studies work that has focused on the politics of Twitter data and the sociotechnical means by which access is regulated. We highlight in particular the contested relationships between social media research (in both academic and non-academic contexts) and the data wholesale, retail, and analytics industries that feed on them. In the second major section of the chapter we discuss in detail the pragmatic edge of these politics in terms of what kinds of scientific research is and is not possible in the current political economy of Twitter data access. Finally, at the end of the chapter we return to the much broader implications of these issues for the politics of knowledge, demonstrating how the apparently microscopic level of how the Twitter API mediates access to Twitter data actually inscribes and influences the macro level of the global political economy of science itself, through re-inscribing institutional and traditional disciplinary privilege We conclude with some speculations about future developments in data rights and data philanthropy that may at least mitigate some of these negative impacts.

Changes in healthcare-associated infections after the introduction of a national hand hygiene initiative

Introduction: Interventions that prevent healthcare-associated infections should lead to fewer deaths and shorter hospital stays. Cleaning hands with soap and water or alcohol rub is an effectiveway to prevent the transmission of organisms, but compliance is sometimes low. The National Hand Hygiene Initiative in Australia aimed to improve hand hygiene compliance among healthcare workers, with the goal of reducing rates of healthcare-associated infections. Methods: We examined if the introduction of the National Hand Hygiene Initiative was associated with a change in infection rates. Monthly infection rates for six types of healthcare-associated infections were examined in 38 Australian hospitals across six states. Infection categories were: bloodstream infections, centralline associated bloodstream infections, methicillin-resistant and methicillin-sensitive Staphylococcus aureus, Staphylococcus aureus bacteraemia and surgical site infections. Results: The National Hand Hygiene Initiative was associated with a statistically significant reduction in infection rates in 11 out of 23 state and infection combinations studied. There was no change in infection rates for nine combinations, and there was an increase in three infection rates in South Australia. Conclusions: The intervention was associated with reduced infection rates in many cases. The lack of improvement in nine cases may have been because they already had effective initiatives before the national initiative’s introduction.

Unsupervised online learning of condition-invariant images for place recognition

This paper presents an online, unsupervised training algorithm enabling vision-based place recognition across a wide range of changing environmental conditions such as those caused by weather, seasons, and day-night cycles. The technique applies principal component analysis to distinguish between aspects of a location’s appearance that are condition-dependent and those that are condition-invariant. Removing the dimensions associated with environmental conditions produces condition-invariant images that can be used by appearance-based place recognition methods. This approach has a unique benefit – it requires training images from only one type of environmental condition, unlike existing data-driven methods that require training images with labelled frame correspondences from two or more environmental conditions. The method is applied to two benchmark variable condition datasets. Performance is equivalent or superior to the current state of the art despite the lesser training requirements, and is demonstrated to generalise to previously unseen locations.

Cold water immersion enhances recovery of submaximal muscle function after resistance exercise

We investigated the effect of cold water immersion (CWI) on the recovery of muscle function and physiological responses following high-intensity resistance exercise. Using a randomized, cross-over design, 10 physically active men performed high-intensity resistance exercise, followed by one of two recovery interventions: 10 min of cold water immersion at 10°C, or 10 min active recovery (low-intensity cycling). After the recovery interventions, maximal muscle function was assessed after 2 h and 4 h by measuring jump height and isometric squat strength. Submaximal muscle function was assessed after 6 h by measuring the average load lifted during six sets of 10 squats at 80% 1RM. Intramuscular temperature (1 cm) was also recorded, and venous blood samples were analyzed for markers of metabolism, vasoconstriction and muscle damage. CWI did not enhance recovery of maximal muscle function. However, during the final three sets of the submaximal muscle function test, the participants lifted a greater load (p<0.05; 38%; Cohen’s d 1.3) following CWI compared with active recovery. During CWI, muscle temperature decreased 6°C below post-exercise values, and remained below pre-exercise values for another 35 min. Venous blood O2 saturation decreased below pre-exercise values for 1.5 h after CWI. Serum endothelin-1 concentration did not change after CWI, whereas it decreased after active recovery. Plasma myoglobin concentration was lower, whereas plasma interleukin-6 concentration was higher after CWI compared with active recovery. These results suggest that cold water immersion after resistance exercise allow athletes to complete more work during subsequent training sessions, which could enhance long-term training adaptations.

Systematic review of pharmacologic and non-pharmacologic interventions to manage cognitive alterations after chemotherapy for breast cancer

Purpose Cognitive alterations are reported in breast cancer patients receiving chemotherapy. This has adverse effects on patients’ quality of life and function. This systematic review investigates the effectiveness of pharmacologic and non-pharmacologic interventions to manage cognitive alterations associated with breast cancer treatment. Methods Medline via EBSCOhost, CINAHL and Cochrane CENTRAL were searched for the period January 1999 to May 2014 for prospective randomized controlled trials related to the management of chemotherapy-associated cognitive alterations. Included studies investigated the management of chemotherapy-associated cognitive alterations and used subjective or objective measures in patients with breast cancer during or after chemotherapy. Two authors independently extracted data and assessed the risk of bias. Results Thirteen studies involving 1138 participants were included. Overall, the risk of bias for the 13 studies were either high (n=11) or unclear (n=2). Pharmacologic interventions included psychostimulants (n=4), epoetin alfa (n=1), and Ginkgo biloba (n=1). Non-pharmacologic interventions were cognitive training (n=5) and physical activity (n=2). Pharmacologic agents were ineffective except for self-reported cognitive function in an epoetin alfa study. Cognitive training interventions demonstrated benefits in self-reported cognitive function, memory, verbal function and language and orientation/attention. Physical activity interventions were effective in improving executive function and self-reported concentration. Conclusion Current evidence does not favor the pharmacologic management of cognitive alterations associated with breast cancer treatment. Cognitive training and physical activity interventions appear promising, but additional studies are required to establish their efficacy. Further research is needed to overcome methodological shortfalls such as heterogeneity in participant characteristics and non-standardized neuropsychological outcome measures.

Women with self-reported lower-limb lymphedema after treatment for gynecological cancers: Are they more likely to self-report psychosocial symptoms and less likely to use services?

Background: Due to improved screening and treatment for gynaecological cancers survivorship has increased. Use of supportive care services after treatment is important to improve quality of life. Objective: To assess self-reported lower-limb lymphoedema (LLL), depression, anxiety, quality of life, unmet supportive care needs, and service use among gynaecological cancer survivors. Methods: In 2010 a population-based cross-sectional mail survey was conducted (n=160 gynaecological cancer survivors 5 to 30 month post-diagnosis (53% response rate)). Results: Overall, 30% of women self-reported LLL, 21% and 24% depression or anxiety, respectively. Women with LLL were more likely to also report symptoms of depression or anxiety, and with these symptoms had higher unmet supportive care needs. Services needed but not used by 10-15% of women with LLL, anxiety or depression respectively were lymphoedema specialist, pain specialist and physiotherapist, or psychiatrists, psychologists and pain specialists. Limitations: Small sample size, self-report data, limited generalisation to other countries, underrepresentation of older women (age >70) and women from non-Caucasian backgrounds. Conclusions: Women with LLL or high distress were less likely to use services they needed. Funding: This study was funded by Cancer Australia.

Tubule detection in testis images using boundary weighting and circular shortest path

In studies of germ cell transplantation, measureing tubule diameters and counting cells from different populations using antibodies as markers are very important. Manual measurement of tubule sizes and cell counts is a tedious and sanity grinding work. In this paper, we propose a new boundary weighting based tubule detection method. We first enhance the linear features of the input image and detect the approximate centers of tubules. Next, a boundary weighting transform is applied to the polar transformed image of each tubule region and a circular shortest path is used for the boundary detection. Then, ellipse fitting is carried out for tubule selection and measurement. The algorithm has been tested on a dataset consisting of 20 images, each having about 20 tubules. Experiments show that the detection results of our algorithm are very close to the results obtained manually. © 2013 IEEE.

Calibration of treatment time intensity modulated EPID images for anatomical imaging

Intensity Modulated Radiotherapy (IMRT) is a well established technique for delivering highly conformal radiation dose distributions. The complexity of the delivery techniques and high dose gradients around the target volume make verification of the patient treatment crucial to the success of the treatment. Conventional treatment protocols involve imaging the patient prior to treatment, comparing the patient set-up to the planned set-up and then making any necessary shifts in the patient position to ensure target volume coverage. This paper presents a method for calibrating electronic portal imaging device (EPID) images acquired during IMRT delivery so that they can be used for verifying the patient set-up.

Standardising and assessing digital images for use in clinical trials : a practical, reproducible method that blinds the assessor to treatment allocation

With the increasing availability of high quality digital cameras that are easily operated by the non-professional photographer, the utility of using digital images to assess endpoints in clinical research of skin lesions has growing acceptance. However, rigorous protocols and description of experiences for digital image collection and assessment are not readily available, particularly for research conducted in remote settings. We describe the development and evaluation of a protocol for digital image collection by the non-professional photographer in a remote setting research trial, together with a novel methodology for assessment of clinical outcomes by an expert panel blinded to treatment allocation.

Assessment of the effects of CT dose in averaged x-ray CT images of a dose-sensitive polymer gel

The signal-to-noise ratio achievable in x-ray computed tomography (CT) images of polymer gels can be increased by averaging over multiple scans of each sample. However, repeated scanning delivers a small additional dose to the gel which may compromise the accuracy of the dose measurement. In this study, a NIPAM-based polymer gel was irradiated and then CT scanned 25 times, with the resulting data used to derive an averaged image and a "zero-scan" image of the gel. Comparison between these two results and the first scan of the gel showed that the averaged and zero-scan images provided better contrast, higher contrast-to- noise and higher signal-to-noise than the initial scan. The pixel values (Hounsfield units, HU) in the averaged image were not noticeably elevated, compared to the zero-scan result and the gradients used in the linear extrapolation of the zero-scan images were small and symmetrically distributed around zero. These results indicate that the averaged image was not artificially lightened by the small, additional dose delivered during CT scanning. This work demonstrates the broader usefulness of the zero-scan method as a means to verify the dosimetric accuracy of gel images derived from averaged x-ray CT data.

Methotrexate-conjugated PEGylated dendrimers show differential patterns of deposition and activity in tumour-burdened lymph nodes after intravenous and subcutaneous administration in rats

The current study sought to explore whether the subcutaneous administration of lymph-targeted dendrimers, conjugated with a model chemotherapeutic (methotrexate, MTX), was able to enhance anticancer activity against lymph node metastases. The lymphatic pharmacokinetics and antitumour activity of PEGylated polylysine dendrimers conjugated to MTX [D-MTX(OH)] via a tumour-labile hexapeptide linker was examined in rats and compared to a similar system where MTX was α-carboxyl O-tert-butylated [D-MTX(OtBu)]. The latter has previously been shown to exhibit longer plasma circulation times. D-MTX(OtBu) was well absorbed from the subcutaneous injection site via the lymph, and 3 to 4%/g of the dose was retained by sentinel lymph nodes. In contrast, D-MTX(OH) showed limited absorption from the subcutaneous injection site, but absorption was almost exclusively via the lymph. The retention of D-MTX(OH) by sentinel lymph nodes was also significantly elevated (approximately 30% dose/g). MTX alone was not absorbed into the lymph. All dendrimers displayed lower lymph node targeting after intravenous administration. Despite significant differences in the lymph node retention of D-MTX(OH) and D-MTX(OtBu) after subcutaneous and intravenous administration, the growth of lymph node metastases was similarly inhibited. In contrast, the administration of MTX alone did not significantly reduce lymph node tumour growth. Subcutaneous administration of drug-conjugated dendrimers therefore provides an opportunity to improve drug deposition in downstream tumour-burdened lymph nodes. In this case, however, increased lymph node biodistribution did not correlate well with antitumour activity, possibly suggesting constrained drug release at the site of action.

Telephone-delivered health coaching improves anxiety outcomes after myocardial infarction: The 'ProActive Heart' trial

Background: Recently, we found a telephone-delivered secondary prevention programme using health coaching (‘ProActive Heart’) to be effective in improving a range of key behavioural outcomes for myocardial infarction (MI) patients. What remains unclear, however, is the extent to which these treatment effects translate to important psychological outcomes such as depression and anxiety outcomes, an issue of clinical significance due to the substantial proportion of MI patients who experience depression and anxiety. The objective of the study was to investigate, as a secondary hypothesis of a larger trial, the effects of a telephone-delivered health coaching programme on depression and anxiety outcomes of MI patients. Design: Two-arm, parallel-group, randomized, controlled design with six-months outcomes. Methods: Patients admitted to one of two tertiary hospitals in Brisbane, Australia following MI were assessed for eligibility. Four hundred and thirty patients were recruited and randomly assigned to usual care or an intervention group comprising up to 10 telephone-delivered ‘health coaching’ sessions (ProActive Heart). Regression analysis compared Hospital Anxiety and Depression Scale scores of completing participants at six months (intervention: n = 141 versus usual care: n = 156). Results: The intervention yielded reductions in anxiety at follow-up (mean difference = −0.7, 95% confidence interval=−1.4,−0.02) compared with usual care. A similar pattern was observed in mean depression scores but was not statistically significant. Conclusions: The ProActive Heart programme effectively improves anxiety outcomes of patients following myocardial infarction. If combined with psychological-specific treatment, this programme could impact anxiety of greater intensity in a clinically meaningful way.

An analysis of DNA methylation in human adipose tissue reveals differential modification of obesity genes before and after gastric bypass and weight loss

Background Environmental factors can influence obesity by epigenetic mechanisms. Adipose tissue plays a key role in obesity-related metabolic dysfunction, and gastric bypass provides a model to investigate obesity and weight loss in humans. Results Here, we investigate DNA methylation in adipose tissue from obese women before and after gastric bypass and significant weight loss. In total, 485,577 CpG sites were profiled in matched, before and after weight loss, subcutaneous and omental adipose tissue. A paired analysis revealed significant differential methylation in omental and subcutaneous adipose tissue. A greater proportion of CpGs are hypermethylated before weight loss and increased methylation is observed in the 3′ untranslated region and gene bodies relative to promoter regions. Differential methylation is found within genes associated with obesity, epigenetic regulation and development, such as CETP, FOXP2, HDAC4, DNMT3B, KCNQ1 and HOX clusters. We identify robust correlations between changes in methylation and clinical trait, including associations between fasting glucose and HDAC4, SLC37A3 and DENND1C in subcutaneous adipose. Genes investigated with differential promoter methylation all show significantly different levels of mRNA before and after gastric bypass. Conclusions This is the first study reporting global DNA methylation profiling of adipose tissue before and after gastric bypass and associated weight loss. It provides a strong basis for future work and offers additional evidence for the role of DNA methylation of adipose tissue in obesity.