The effectiveness of dietary counselling versus oral nutrition supplements in improving nutritional intake in malnourished patients with Chronic Obstructive Pulmonary Disease (COPD)

The evidence for nutritional support in COPD is almost entirely based on oral nutritional supplements (ONS) yet despite this dietary counseling and food fortification (DA) are often used as the first line treatment for malnutrition. This study aimed to investigate the effectiveness of ONS vs. DA in improving nutritional intake in malnourished outpatients with COPD. 70 outpatients (BMI 18.4 SD 1.6 kg/m2, age 73 SD 9 years, severe COPD) were randomised to receive a 12-week intervention of either ONS or DA (n 33 ONS vs. n 37 DA). Paired t-test analysis revealed total energy intakes significantly increased with ONS at week 6 (+302 SD 537 kcal/d; p = 0.002), with a slight reduction at week 12 (+243 SD 718 kcal/d; p = 0.061) returning to baseline levels on stopping supplementation. DA resulted in small increases in energy that only reached significance 3 months post-intervention (week 6: +48 SD 623 kcal/d, p = 0.640; week 12: +157 SD 637 kcal/d, p = 0.139; week 26: +247 SD 592 kcal/d, p = 0.032). Protein intake was significantly higher in the ONS group at both week 6 and 12 (ONS: +19.0 SD 25.0 g/d vs. DA: +1.0 SD 13.0 g/d; p = 0.033 ANOVA) but no differences were found at week 26. Vitamin C, Iron and Zinc intakes significantly increased only in the ONS group. ONS significantly increased energy, protein and several micronutrient intakes in malnourished COPD patients but only during the period of supplementation. Trials investigating the effects of combined nutritional interventions are required.

The effect of deprivation and disease-severity on malnutrition risk in chronic obstructive pulmonary disease (COPD)

Deprivation has previously been shown to be an independent risk factor for the high prevalence of malnutrition observed in COPD (Collins et al., 2010). It has been suggested the socioeconomic gradient observed in COPD is greater than any other chronic disease (Prescott & Vestbo, 1999). The current study aimed to examine the infl uence of disease severity and social deprivation on malnutrition risk in outpatients with COPD. 424 COPD outpatients were screened using the ‘Malnutrition Universal Screening Tool’ (‘MUST’). COPD disease severity was recorded in accordance with the GOLD criteria and deprivation was established according to the patient’s geographical location (postcode) at the time of nutritional screening using the UK Government’s Index of Multiple Deprivation (IMD). IMD ranks postcodes from 1 (most deprived) to 32,482 (least deprived). Disease severity was posi tively associated with an increased prevalence of malnutrition risk (p < 0.001) both within and between groups, whilst rank IMD was negatively associated with malnutrition (p = 0.020), i.e. those residing in less deprived areas were less likely to be malnourished. Within each category of disease severity the prevalence of malnutrition was two-fold greater in those residing in the most deprived areas compared to those residing in the least deprived areas. This study suggests that deprivation and disease severity are independent risk factors for malnutrition in COPD both contributing to the widely variable prevalence of malnutrition. Consideration of these issues could assist with the targeted nutritional management of these patients.

Who is seeing the dietitian? we are only seeing the tip of the iceberg

Poor dietary choices are associated with overweight and obesity and the development of chronic conditions. Over 12 million (~60%) Australians are currently overweight or obese. Accredited Practicing Dietitians (APDs) are the experts in nutrition and diet therapy, equipped to provide services and counselling to assist individuals in making dietary modifications to prevent or manage diet-related conditions. However, no existing research has investigated the proportion or characteristics of the Australian population that may be accessing APDs. Data from 25,906 participants in the 2004/05 National Health Survey (NHS) were analysed using logistic regression to identify the sociodemographic and health characteristics of individuals accessing an APD or Nutritionist. Only 0.4% (n = 105) of the sample reported accessing a Dietitian or Nutritionist, this was half the amount accessing a Naturopath. Diabetes Mellitus, cardiovascular disease and obesity were all significantly associated with having seen a Dietitian, and over 90% of those accessing services had a long-term condition. Of the total sample only 10% of those with a diet-related condition had seen an APD or Nutritionist. Household income and education were not associated with accessing an APD. Exploration around the barriers to referral and accessing services may be warranted to assist in enhancing the profile of APDs among the population and other healthcare professionals. The current number of approximately 5000 registered APDs is unlikely to be able to service the proportion of the population who require dietary intervention; further avenues for prevention, rather than acute treatment, and novel strategies for service provision also need to be explored.

Ineffective cerebral perfusion related to increased intracranial pressure secondary to subarachnoid haemorrhage : An examination of nursing interventions

Considered a condition of the elderly population, stroke will soon be the leading cause of death globally. In Singapore it is the fourth leading cause of death after cancer and heart disease. Subarachnoid haemorrhage, when compared with an embolic stroke, has a more devastating outcome because of the deleterious complications associated with it. Vasospam, re-bleeding and global cerebral ischemia are three of the most prominent complications. Therefore, nursing care and interventions developed to reduce the incidence of complications and optimise neurological function are critical in the acute phase of this condition. Using a casestudy approach this article will discuss and offer a rationale to a number of key nursing interventions based around a nursing care plan designed to reduce the incidence of complications.

Understanding welding practices on shipyards : an ethnographic study for designing an interactive robot welder

The aim of this ethnographic study was to understand welding practices in shipyard environments with the purpose of designing an interactive welding robot that can help workers with their daily job. The robot is meant to be deployed for automatic welding on jack-up rig structures. The design of the robot turns out to be a challenging task due to several problematic working conditions on the shipyard, such as dust, irregular floor, high temperature, wind variations, elevated working platforms, narrow spaces, and circular welding paths requiring a robotic arm with more than 6 degrees of freedom. Additionally, the environment is very noisy and the workers – mostly foreigners – have a very basic level of English. These two issues need to be taken into account when designing the interactive user interface for the robot. Ideally, the communication flow between the two parties involved should be as frictionless as possible. The paper presents the results of our field observations and welders’ interviews, as well as our robot design recommendation for the next project stage.

A numerical method for the fractional Fitzhugh–Nagumo monodomain model

A fractional FitzHugh–Nagumo monodomain model with zero Dirichlet boundary conditions is presented, generalising the standard monodomain model that describes the propagation of the electrical potential in heterogeneous cardiac tissue. The model consists of a coupled fractional Riesz space nonlinear reaction-diffusion model and a system of ordinary differential equations, describing the ionic fluxes as a function of the membrane potential. We solve this model by decoupling the space-fractional partial differential equation and the system of ordinary differential equations at each time step. Thus, this means treating the fractional Riesz space nonlinear reaction-diffusion model as if the nonlinear source term is only locally Lipschitz. The fractional Riesz space nonlinear reaction-diffusion model is solved using an implicit numerical method with the shifted Grunwald–Letnikov approximation, and the stability and convergence are discussed in detail in the context of the local Lipschitz property. Some numerical examples are given to show the consistency of our computational approach.

Repositioning "old" drugs for new causes : identifying new treatments for prostate cancer

The majority of prostate cancer related deaths are due to the spread of the disease. This project developed a screening protocol to identify existing drugs that could be used to prevent the spread of prostate cancer and thereby improve the survival of the patients.

Common values in assessing health outcomes from disease and injury: Disability weights measurement study for the Global Burden of Disease Study 2010

BACKGROUND Measurement of the global burden of disease with disability-adjusted life-years (DALYs) requires disability weights that quantify health losses for all non-fatal consequences of disease and injury. There has been extensive debate about a range of conceptual and methodological issues concerning the definition and measurement of these weights. Our primary objective was a comprehensive re-estimation of disability weights for the Global Burden of Disease Study 2010 through a large-scale empirical investigation in which judgments about health losses associated with many causes of disease and injury were elicited from the general public in diverse communities through a new, standardised approach. METHODS We surveyed respondents in two ways: household surveys of adults aged 18 years or older (face-to-face interviews in Bangladesh, Indonesia, Peru, and Tanzania; telephone interviews in the USA) between Oct 28, 2009, and June 23, 2010; and an open-access web-based survey between July 26, 2010, and May 16, 2011. The surveys used paired comparison questions, in which respondents considered two hypothetical individuals with different, randomly selected health states and indicated which person they regarded as healthier. The web survey added questions about population health equivalence, which compared the overall health benefits of different life-saving or disease-prevention programmes. We analysed paired comparison responses with probit regression analysis on all 220 unique states in the study. We used results from the population health equivalence responses to anchor the results from the paired comparisons on the disability weight scale from 0 (implying no loss of health) to 1 (implying a health loss equivalent to death). Additionally, we compared new disability weights with those used in WHO's most recent update of the Global Burden of Disease Study for 2004. FINDINGS 13,902 individuals participated in household surveys and 16,328 in the web survey. Analysis of paired comparison responses indicated a high degree of consistency across surveys: correlations between individual survey results and results from analysis of the pooled dataset were 0·9 or higher in all surveys except in Bangladesh (r=0·75). Most of the 220 disability weights were located on the mild end of the severity scale, with 58 (26%) having weights below 0·05. Five (11%) states had weights below 0·01, such as mild anaemia, mild hearing or vision loss, and secondary infertility. The health states with the highest disability weights were acute schizophrenia (0·76) and severe multiple sclerosis (0·71). We identified a broad pattern of agreement between the old and new weights (r=0·70), particularly in the moderate-to-severe range. However, in the mild range below 0·2, many states had significantly lower weights in our study than previously. INTERPRETATION This study represents the most extensive empirical effort as yet to measure disability weights. By contrast with the popular hypothesis that disability assessments vary widely across samples with different cultural environments, we have reported strong evidence of highly consistent results.

Cryptographic hash functions

Cryptographic hash functions are an important tool of cryptography and play a fundamental role in efficient and secure information processing. A hash function processes an arbitrary finite length input message to a fixed length output referred to as the hash value. As a security requirement, a hash value should not serve as an image for two distinct input messages and it should be difficult to find the input message from a given hash value. Secure hash functions serve data integrity, non-repudiation and authenticity of the source in conjunction with the digital signature schemes. Keyed hash functions, also called message authentication codes (MACs) serve data integrity and data origin authentication in the secret key setting. The building blocks of hash functions can be designed using block ciphers, modular arithmetic or from scratch. The design principles of the popular Merkle–Damgård construction are followed in almost all widely used standard hash functions such as MD5 and SHA-1.

Security Analysis of Randomize-Hash-then-Sign Digital Signatures

At CRYPTO 2006, Halevi and Krawczyk proposed two randomized hash function modes and analyzed the security of digital signature algorithms based on these constructions. They showed that the security of signature schemes based on the two randomized hash function modes relies on properties similar to the second preimage resistance rather than on the collision resistance property of the hash functions. One of the randomized hash function modes was named the RMX hash function mode and was recommended for practical purposes. The National Institute of Standards and Technology (NIST), USA standardized a variant of the RMX hash function mode and published this standard in the Special Publication (SP) 800-106. In this article, we first discuss a generic online birthday existential forgery attack of Dang and Perlner on the RMX-hash-then-sign schemes. We show that a variant of this attack can be applied to forge the other randomize-hash-then-sign schemes. We point out practical limitations of the generic forgery attack on the RMX-hash-then-sign schemes. We then show that these limitations can be overcome for the RMX-hash-then-sign schemes if it is easy to find fixed points for the underlying compression functions, such as for the Davies-Meyer construction used in the popular hash functions such as MD5 designed by Rivest and the SHA family of hash functions designed by the National Security Agency (NSA), USA and published by NIST in the Federal Information Processing Standards (FIPS). We show an online birthday forgery attack on this class of signatures by using a variant of Dean’s method of finding fixed point expandable messages for hash functions based on the Davies-Meyer construction. This forgery attack is also applicable to signature schemes based on the variant of RMX standardized by NIST in SP 800-106. We discuss some important applications of our attacks and discuss their applicability on signature schemes based on hash functions with ‘built-in’ randomization. Finally, we compare our attacks on randomize-hash-then-sign schemes with the generic forgery attacks on the standard hash-based message authentication code (HMAC).

Cryptanalysis of the 10-Round Hash and Full Compression Function of SHAvite-3-512

In this paper, we analyze the SHAvite-3-512 hash function, as proposed and tweaked for round 2 of the SHA-3 competition. We present cryptanalytic results on 10 out of 14 rounds of the hash function SHAvite-3-512, and on the full 14 round compression function of SHAvite-3-512. We show a second preimage attack on the hash function reduced to 10 rounds with a complexity of 2497 compression function evaluations and 216 memory. For the full 14-round compression function, we give a chosen counter, chosen salt preimage attack with 2384 compression function evaluations and 2128 memory (or complexity 2448 without memory), and a collision attack with 2192 compression function evaluations and 2128 memory.

On Randomizing Hash Functions to Strengthen the Security of Digital Signatures

Halevi and Krawczyk proposed a message randomization algorithm called RMX as a front-end tool to the hash-then-sign digital signature schemes such as DSS and RSA in order to free their reliance on the collision resistance property of the hash functions. They have shown that to forge a RMX-hash-then-sign signature scheme, one has to solve a cryptanalytical task which is related to finding second preimages for the hash function. In this article, we will show how to use Dean’s method of finding expandable messages for finding a second preimage in the Merkle-Damgård hash function to existentially forge a signature scheme based on a t-bit RMX-hash function which uses the Davies-Meyer compression functions (e.g., MD4, MD5, SHA family) in 2 t/2 chosen messages plus 2 t/2 + 1 off-line operations of the compression function and similar amount of memory. This forgery attack also works on the signature schemes that use Davies-Meyer schemes and a variant of RMX published by NIST in its Draft Special Publication (SP) 800-106. We discuss some important applications of our attack.

Cryptographic Hash Functions

In the modern era of information and communication technology, cryptographic hash functions play an important role in ensuring the authenticity, integrity, and nonrepudiation goals of information security as well as efficient information processing. This entry provides an overview of the role of hash functions in information security, popular hash function designs, some important analytical results, and recent advances in this field.