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Infants born preterm miss out on the peak period of in utero DHA accretion to the brain during the last trimester of pregnancy which is hypothesised to contribute to the increased prevalence of neurodevelopmental deficits in this population. This study aimed to determine whether DHA supplementation in infants born preterm improves attention at 18 months’ corrected age. This is a follow-up of a subset of infants who participated in the N3RO randomised controlled trial. Infants were randomised to receive an enteral emulsion of high-dose DHA (60 mg/kg per d) or no DHA (soya oil – control) from within the first days of birth until 36 weeks’ post-menstrual age. The assessment of attention involved three tasks requiring the child to maintain attention on toy/s in either the presence or absence of competition or a distractor. The primary outcome was the child’s latency of distractibility when attention was focused on a toy. The primary outcome was available for seventy-three of the 120 infants that were eligible to participate. There was no evidence of a difference between groups in the latency of distractibility (adjusted mean difference: 0·08 s, 95 % CI –0·81, 0·97; P = 0·86). Enteral DHA supplementation did not result in improved attention in infants born preterm at 18 months’ corrected age.
Although contamination of food can occur at any point from farm to table, restaurant food workers are a common source of foodborne illness. We describe the characteristics of restaurant-associated foodborne disease outbreaks and explore the role of food workers by analysing outbreaks associated with restaurants from 1998 to 2013 reported to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System. We identified 9788 restaurant-associated outbreaks. The median annual number of outbreaks was 620 (interquartile range 618–629). In 3072 outbreaks with a single confirmed aetiology reported, norovirus caused the largest number of outbreaks (1425, 46%). Of outbreaks with a single food reported and a confirmed aetiology, fish (254 outbreaks, 34%) was most commonly implicated, and these outbreaks were commonly caused by scombroid toxin (219 outbreaks, 86% of fish outbreaks). Most outbreaks (79%) occurred at sit-down establishments. The most commonly reported contributing factors were those related to food handling and preparation practices in the restaurant (2955 outbreaks, 61%). Food workers contributed to 2415 (25%) outbreaks. Knowledge of the foods, aetiologies, and contributing factors that result in foodborne disease restaurant outbreaks can help guide efforts to prevent foodborne illness.
Suicide message boards have been at the core of debates about negative influences of the Internet on suicidality. Nothing is currently known about communication styles that may help users to psychologically improve in these settings.
In all, 1182 archival threads with 20 499 individual postings from seven non-professional suicide message boards supporting an ‘against-suicide’, ‘neutral’ or ‘pro-suicide’ attitude were randomly selected and subject to content analysis. Initial needs of primary posters (i.e. individual who open a thread), their psychological improvement by the end of the thread, their responses received and indicators of suicidality were coded. Differences between ‘pro-suicide’, ‘neutral’ and ‘against suicide’ boards, and correlations between primary posters and respondents in terms of suicidality were assessed. Logistic regression was used to test associations with psychological improvement.
‘Pro-suicide’ boards (n = 4) differed from ‘neutral’ (n = 1) and ‘against-suicide’ (n = 2) boards in terms of communicated contents. Indicators of suicidality correlated moderately to strongly between primary posters and respondents on ‘pro-suicide’ message boards, but less on other boards. Several communicative strategies were associated with psychological improvement in primary posters, including the provision of constructive advice [adjusted odds ratio (aOR) 4.10, 95% confidence interval (CI) 2.40–7.03], active listening (aOR 1.60, 95% CI 1.12–2.27), sympathy towards the poster (aOR 2.22, 95% CI 1.68–2.95) and provision of alternatives to suicide (aOR 2.30, 95% CI 1.67–3.18).
Respondents resemble primary posters with regard to suicidality in ‘pro-suicide’ boards, which may hinder psychological improvement. Still, opportunities to intervene in these settings using simple communication techniques exist and need to be taken and evaluated.
Catheter-associated urinary tract infection (CAUTI) is considered a reasonably preventable event in the hospital setting, and it has been included in the US Department of Health and Human Services National Action Plan to Prevent Healthcare-Associated Infections. While multiple definitions for measuring CAUTI exist, each has important limitations, and understanding these limitations is important to both clinical practice and policy decisions. The National Healthcare Safety Network (NHSN) surveillance definition, the most frequently used outcome measure for CAUTI prevention efforts, has limited clinical correlation and does not necessarily reflect noninfectious harms related to the catheter. We advocate use of the device utilization ratio (DUR) as an additional performance measure for potential urinary catheter harm. The DUR is patient-centered and objective and is currently captured as part of NHSN reporting. Furthermore, these data are readily obtainable from electronic medical records. The DUR also provides a more direct reflection of improvement efforts focused on reducing inappropriate urinary catheter use.
Infect. Control Hosp. Epidemiol. 2016;37(3):327–333
Amyotrophic lateral sclerosis (ALS) is an adult-onset disease characterized by the selective degeneration of motor neurons in the brain and spinal cord resulting in progressive paralysis and death. Current diagnosis of ALS is based on clinical assessment of related symptoms, which appear only late in the disease course after degeneration of a significant number of motor neurons. As a result, the identification and development of disease-modifying therapies is difficult, making ALS an incurable disease. Novel strategies for early diagnosis of ALS, to monitor disease progression and to assess response to existing and future treatments are urgently needed.
Many neurological disorders, including ALS, are accompanied by skin changes that often precede the onset of neurological symptoms. We have developed a unique ALS tissue-engineered skin model (ALS-TES), derived from the cells of ALS patients, in order to study the earliest stages of ALS-related skin pathology. For each participant, two skin biopsies were collected using a 6-mm diameter punch biopsy. Tissue-engineered skin was then generated from isolated keratinocytes and fibroblasts, and examined by routine histochemistry and immunohistochemistry, as well as by confocal microscopy. The ALS-TES model presents a number of striking features including altered epidermal differentiation, abnormal dermo-epidermal junction, delamination, keratinocyte infiltration, collagen disorganization and cytoplasmic TDP-43 inclusions, which are not seen in skin models derived from healthy subjects. The same abnormal skin model changes were detected skin models derived from the cells of pre- symptomatic C9orf72-linked ALS patients carrying the GGGGCC DNA repeat expansion. Consequently, our ALS-TES skin model could represent a renewable source of human tissue to better understand the physiopathological mechanisms underlying this disease, including cytoplasmic TDP43 accumulation, and lead to better tools for early diagnosis and disease monitoring.
Piglets reared in swine production in the USA undergo painful procedures that include castration, tail docking, teeth clipping, and identification with ear notching or tagging. These procedures are usually performed without pain mitigation. The objective of this project was to develop recommendations for pain mitigation in 1- to 28-day-old piglets undergoing these procedures. The National Pork Board funded project to develop recommendations for pain mitigation in piglets. Recommendation development followed a defined multi-step process that included an evidence summary and estimates of the efficacies of interventions. The results of a systematic review of the interventions were reported in a companion paper. This manuscript describes the recommendation development process and the final recommendations. Recommendations were developed for three interventions (CO2/O2 general anesthesia, non-steroidal anti-inflammatory drugs (NSAIDs), and lidocaine) for use during castration. The ability to make strong recommendations was limited by low-quality evidence and strong certainty about variation in stakeholder values and preferences. The panel strongly recommended against the use of a CO2/O2 general anesthesia mixture, weakly recommended for the use of NSAIDs and weakly recommended against the use of lidocaine for pain mitigation during castration of 1- to 28-day-old piglets.
To estimate the proportion of patients who acquire methicillin-resistant Staphylococcus aureus (MRSA) while in hospital and to identify risk factors associated with acquisition of MRSA.
Retrospective cohort study.
Adult patients discharged from 36 general specialty wards of 2 Scottish hospitals that had implemented universal screening for MRSA on admission.
Patients were screened for MRSA on discharge from hospital by using multisite body swabs that were tested by culture. Discharge screening results were linked to admission screening results. Genotyping was undertaken to identify newly acquired MRSA in MRSA-positive patients on admission.
Of the 5,155 patients screened for MRSA on discharge, 2.9% (95% confidence interval [CI], 2.43–3.34) were found to be positive. In the subcohort screened on both admission and discharge (n = 2,724), 1.3% of all patients acquired MRSA while in hospital (incidence rate, 2.1/1,000 hospital bed-days in this cohort [95% CI, 1.5–2.9]), while 1.3% remained MRSA positive throughout hospital stay. Three risk factors for acquisition of MRSA were identified: age above 64 years, self-reported renal failure, and self-reported presence of open wounds. On a population level, the prevalence of MRSA colonization did not differ between admission and discharge.
Cross-transmission of MRSA takes place in Scottish hospitals that have implemented universal screening for MRSA. This study reinforces the importance of infection prevention and control measures to prevent MRSA cross-transmission in hospitals; universal screening for MRSA on admission will in itself not be sufficient to reduce the number of MRSA colonizations and subsequent MRSA infections.
Nanoporous MgAl2O4 particulates with high porosities were successfully prepared from sol-gel reactions, solvent exchange with castor oil and subsequent combustion and calcination at 700 °C. The products were crystalline and semitransparent. Changes in the metal precursor concentrations allowed control of pore volumes from 0.7 to 1.1 cm3/g and average pore sizes from 14 to 19 nm. The specific surface areas are about 200 m2/g regardless of the precursor concentrations. After heating at 1000 °C for 10 hours, the products kept about 70% of their original pore volume and about 60% of the original surface area. Heating at 1100 °C caused a drastic reduction of pore volume and surface area to 40 and 36%, respectively, as the average particle size increased to 23 nm.
A transition of porous structures in monolithic poly(methylsilsesquioxane) (PMSQ, CH3SiO1.5) gels from uniform mesopores to hierarchical pore structures consisting of macro- and mesopores, has been investigated using a sol-gel system containing surfactant Pluronic F127. A broad variation of porous morphology is controlled by changing the concentration of F127. Sufficient concentrations of F127 inhibit the occurrence of macroscopic phase separation of hydrophobic PMSQ condensates and lead to well-defined mesoporous transparent aerogels with high specific pore volume. Mesopores are developed through microscopic phase separation of PMSQ colloid-surfactant complexes in the solvent. Macroscopic phase separation regulates well-defined macropores in the micrometer range on decreasing concentrations of F127, in which microscopic phase separation concurrently takes place in the PMSQ-rich gelling phase after the onset of macroscopic phase separation. Monolithic PMSQ gels with hierarchical macro- and mesopore structures are consequently obtained.
Experiments and analysis have been conducted to characterize flow separators used in applications where heated fluid passes between layers of solid material such as in the manufacturing of gelatinous materials. The Biot number of the configuration is the key parameter, and must be taken into account when optimizing performance. It is shown that most prior work was for low Biot number systems, and the particular configurations under consideration operate at high Biot number. Existing designs developed for lower Biot number (such as membrane filter spacers) are shown to perform poorly for this application. An experimental apparatus was designed and fabricated to quantitatively assess pressure drop through the system using different separation strategies. These results were compared with a simplified two-term model based on the physics of viscous drag in these devices. Channels without separators behave like classical Poiseuille flow. Channels with separators can be modeled with a two-term equation: a baseline Poiseuille term and a form drag term. A variety of separator designs are compared and their overall performance is discussed. We also illustrate the high sensitivity to gap height in all configurations.
We describe organic aerogels derived from multifunctional isocyanates through reaction with water (polyureas), acid andydrides (polyimides) and carboxylic acids (polyamides). All processes are invariably single-step, one-pot and take place at room or slightly elevated temperatures. The resulting materials are robust, their density may vary over a very wide range and their nanomorphology can be either particulate or fibrous, but in all cases they all consist of similarly sized primary particles.
Mesoporous organosilicate materials combine tunable binding characteristics, high surface area, and low materials density with an ordered pore network. Surface modifications provide the potential for incorporation of a variety of functional groups. We have taken advantage of these characteristics for the development of a range of materials to be utilized in various applications. In one approach, porphyrins are incorporated into the materials to provide unique catalytic properties. In these materials, the organosilicate scaffold stabilizes the porphyrin catalyst and facilitates interaction of the catalyst and target. Catalysis can be stimulated through exposure to light or application of an electrical current. The selectivity of the materials can be influenced through choice of organic bridging groups in the organosilicate structure and through selection of the porphyrin component. In addition, a type of molecular imprinting can be applied to provide sites on the pore walls that enhance adsorption selectivity for the target. These materials are directed at the development of self-decontaminating surfaces and coatings. Similar materials characteristics have been utilized in the development of solidphase extraction materials for use in the pre-concentration of nitroenergetic targets from ground and surface water samples. These materials are being incorporated into systems for in situ water quality monitoring. Mesoporous organosilicates can also be applied to the encapsulation of proteins and nucleic acids, stabilizing them for wider application of technologies utilizing these reagents. Modifications to the pore surfaces, in this case, are used to incorporate stabilizing agents such as sugars and proteins which should extend shelf-life and reduce storage restrictions.
There are a lot of synthetic polymers which can be used for controlled drug delivery, however they are not easily accepted by the organism. Also incorporation of drugs into carriers runs under difficult conditions. Therefore scientists have been inclined to use natural-origin polymers, such as proteins and polysaccharides. Some of these promising natural polysaccharidic candidates are alginic acid sodium salt, guar gum and chitosan due to their outstanding merits. They are similar to extracellular matrix having high chemical versatility, good biological performance and cell or enzyme-controlled degradability. Many polysaccharidic hydrogels for drug delivery have already been prepared, but one of their weakness is their short life in dry air conditions; thus, special coating materials are being developed for enhancing their life time.
Alginates were used in the present research for synthesis of organic biodegradable gels by sol-gel process, which were further easily converted to aerogels by supercritical drying. They are safe for use, nontoxic, and derived from renewable sources. Aerogels made of alginate are dry and stable materials, which makes them interesting as a substitute to hydrogels. Alginates undergo reversible gelation in aqueous solution through interaction with divalent cations such as Ca2+, which create ionic inter-chain bridges. Two fundamental methods of ionic cross-linking were used to prepare alginate hydrogels: the diffusion method, where spheres are created and the internal setting method resulting in monoliths. After producing the hydrogel, alcogels were formed by solvent exchange using 100% ethanol. Ethanol was later replaced by supercritical CO2 with supercritical drying (100 bar, 35°C). Aerogels made from natural polysaccharides combine both biocharacteristics and aerogel characteristics such as high porosity and specific surface area, which makes them really attractive in drug delivery applications. The aerogels obtained in present research were therefore studied as drug carriers. The effects of the alginate composition and synthesis method on model drug nicotinic acid release were investigated. The results indicated that by using the internal setting cross-linking method for obtaining aerogels nicotinic acid was released in a more controlled manner. That is why further investigation was done on alginate spherical beads for prolonging their drug release. A multi-step sol-gel process was applied to generate complex aerogels with multi-membranes. First ionically cross-linked spherical cores were obtained by dropwise addition of sodium alginate solution into a CaCl2 solution. These cores were further immersed into alginate solution, filtered through a sieve and dropped into a salt solution again. By repeating the above process, different multi-membrane hydrogels were produced and further converted to aerogels. By adding more membranes around core burst drug release was successfully inhibited.
This article examines, from the energy viewpoint, a new lightweight, slim, high energy efficient, light-transmitting envelope system, providing for seamless, free-form designs for use in architectural projects. The research was based on envelope components already existing on the market, especially components implemented with granular silica aerogel insulation, as this is the most effective translucent thermal insulation there is today. The tests run on these materials revealed that there is not one that has all the features required of the new envelope model, although some do have properties that could be exploited to generate this envelope, namely, the vacuum chamber of vacuum insulated panels (VIP), the monolithic aerogel used as insulation in some prototypes, and reinforced polyester barriers. By combining these three design components — the high-performance thermal insulation of the vacuum chamber combined with monolithic silica aerogel insulation, the free-form design potential provided by materials like reinforced polyester and epoxy resins—, we have been able to define and test a new, variable geometry, energy-saving envelope system.