Impact of Facilitated Behavior Change Strategies on Food Intake Monitoring and Body Weight Measurements in Acute Care: Case Examples From the More-2-Eat Study

BACKGROUND

Assessing and monitoring food intake and body weight of all hospital patients is considered part of "best practice" nutrition care. This study presents case examples describing the impact of behavior change strategies on embedding these 2 monitoring processes in hospitals.

METHODS

Four hospital medical units that participated in the More-2-Eat implementation study to improve nutrition care focused on improving food intake and/or weight monitoring practices. The percentage of admitted patients who received these care practices were tracked through chart audits over 18 months. Implementation progress and behavior change strategies were documented through interviews, focus groups, scorecards, and monthly telephone calls. Case examples are explored using mixed methods.

RESULTS

Of the 4 units, 3 implemented food intake monitoring. One provided food service workers the opportunity to record food intake, with low intake discussed by an interdisciplinary team during bedside rounds (increased from 0% to 97%). Another went from 0% to 61% of patients monitored by introducing a new form ("environmental restructuring") reminding staff to ask patients about low intake. A third unit increased motivation to improve documentation of low intake and improved from 3% to 95%. Two units focused on regularity of body weight measurement. One unit encouraged a team approach and introduced 2 weigh days/week (improved from 14% to 63%), while another increased opportunity by having all patients weighed on Saturdays (improved from 11% to 49%).

CONCLUSION

Difficult-to-change nutrition care practices can be implemented using diverse and ongoing behavior change strategies, staff input, a champion, and an interdisciplinary team.

Multi-site implementation of nutrition screening and diagnosis in medical care units: Success of the More-2-Eat project

BACKGROUND

Improving the detection and treatment of malnourished patients in hospital is needed to promote recovery.

AIM

To describe the change in rates of detection and triaging of care for malnourished patients in 5 hospitals that were implementing an evidence-based nutrition care algorithm. To demonstrate that following this algorithm leads to increased detection of malnutrition and increased treatment to mitigate this condition.

METHODS

Sites worked towards implementing the Integrated Nutrition Pathway for Acute Care (INPAC), including screening (Canadian Nutrition Screening Tool) and triage (Subjective Global Assessment; SGA) to detect and diagnose malnourished patients. Implementation occurred over a 24-month period, including developmental (Period 1), implementation (Periods 2-5), and sustainability (Period 6) phases. Audits (n = 36) of patient health records (n = 5030) were conducted to identify nutrition care practices implemented with a variety of strategies and behaviour change techniques.

RESULTS

All sites increased nutrition screening from Period 1, with three achieving the goal of 75% of admitted patients being screened by Period 3, and the remainder achieving a rate of 70% by end of implementation. No sites were conducting SGA at Period 1, and sites reached the goal of a 75% completion rate or referral for those identified to be at nutrition risk, by Period 3 or 4. By Period 2, 100% of patients identified as SGA C (severely malnourished) were receiving a comprehensive nutritional assessment. In Period 1, the nutrition diagnosis and documentation by the dietitian of 'malnutrition' was a modest 0.37%, increasing to over 5% of all audited health records. The overall use of any Advanced Nutrition Care practices increased from 31% during Period 1 to 63% during Period 6.

CONCLUSION

The success of this multi-site study demonstrated that implementation of nutrition screening and diagnosis is feasible and leads to appropriate care. INPAC promotes efficiency in nutrition care while minimizing the risk of missing malnourished patients.

TRIAL REGISTRATION

Retrospectively registered ClinicalTrials.gov Identifier: NCT02800304, June 7, 2016.

Update on the Integrated Nutrition Pathway for Acute Care (INPAC): post implementation tailoring and toolkit to support practice improvements

The Integrated Nutrition Pathway for Acute Care (INPAC) is an evidence and consensus based pathway developed to guide health care professionals in the prevention, detection, and treatment of malnutrition in medical and surgical patients. From 2015 to 2017, the More-2-Eat implementation project (M2E) used a participatory action research approach to determine the feasibility, and evaluate the implementation of INPAC in 5 hospital units across Canada. Based on the findings of M2E and consensus with M2E stakeholders, updates have been made to INPAC to enhance feasibility in Canadian hospitals. The learnings from M2E have been converted into an online toolkit that outlines how to implement the key steps within INPAC. The aim of this short report is to highlight the updated version of INPAC, and introduce the implementation toolkit that was used to support practice improvements towards this standard.

Assessing the Effect of Preoperative Nutrition on Upper Body Function in Elderly Patients Undergoing Elective Abdominal Surgery

BACKGROUND

Malnutrition among elderly surgical patients has been associated with poor postoperative outcomes and reduced functional status. Although previous studies have shown that nutrition contributes to patient outcomes, its long-term impact on functional status requires better characterization. This study examines the effect of nutrition on postoperative upper body function over time in elderly patients undergoing elective surgery.

METHODS

This is a 2-year prospective study of elderly patients (≥70 years) undergoing elective abdominal surgery. Preoperative nutrition status was determined with the Subjective Global Assessment (SGA). The primary outcome was handgrip strength (HGS) at 1, 4, 12, and 24 weeks postsurgery. Repeated measures analysis was used to determine whether SGA status affects the trajectory of postoperative HGS.

RESULTS

The cohort included 144 patients with a mean age of 77.8 ± 5.0 years and a mean body mass index of 27.7 ± 5.1 kg/m² . The median (interquartile range) Charlson Comorbidity Index was 3 (2-6). Participants were categorized as well-nourished (86%) and mildly to moderately malnourished (14%), with mean preoperative HGS of 25.8 ± 9.2 kg and 19.6 ± 7.0 kg, respectively. At 24 weeks, 64% of well-nourished patients had recovered to baseline HGS, compared with 44% of mildly to moderately malnourished patients. Controlling for relevant covariates, SGA did not significantly affect the trajectory of postoperative HGS.

CONCLUSION

While HGS values over the 24 weeks were consistently higher in the well-nourished SGA group than the mildly to moderately malnourished SGA group, no difference in the trajectories of HGS was detected between the groups.

Costs of hospital malnutrition

BACKGROUND & AIMS

Hospital malnutrition has been established as a critical, prevalent, and costly problem in many countries. Many cost studies are limited due to study population or cost data used. The aims of this study were to determine: the relationship between malnutrition and hospital costs; the influence of confounders on, and the drivers (medical or surgical patients or degree of malnutrition) of the relationship; and whether hospital reported cost data provide similar information to administrative data. To our knowledge, the last two goals have not been studied elsewhere.

METHODS

Univariate and multivariate analyses were performed on data from the Canadian Malnutrition Task Force prospective cohort study combined with administrative data from the Canadian Institute for Health Information. Subjective Global Assessment was used to assess the relationship between nutritional status and length of stay and hospital costs, controlling for health and demographic characteristics, for 956 patients admitted to medical and surgical wards in 18 hospitals across Canada.

RESULTS

After controlling for patient and hospital characteristics, moderately malnourished patients' (34% of surveyed patients) hospital stays were 18% (p = 0.014) longer on average than well-nourished patients. Medical stays increased by 23% (p = 0.014), and surgical stays by 32% (p = 0.015). Costs were, on average, between 31% and 34% (p-values < 0.05) higher than for well-nourished patients with similar characteristics. Severely malnourished patients (11% of surveyed patients) stayed 34% (p = 0.000) longer and had 38% (p = 0.003) higher total costs than well-nourished patients. They stayed 53% (p = 0.001) longer in medical beds and had 55% (p = 0.003) higher medical costs, on average. Trends were similar no matter the type of costing data used.

CONCLUSIONS

Over 40% of patients were found to be malnourished (1/3 moderately and 1/10 severely). Malnourished patients had longer hospital stays and as a result cost more than well-nourished patients.

N-acetyl-L-tyrosine as a tyrosine source in adult parenteral nutrition

BACKGROUND

N-acetyl-L-tyrosine (NAT) is commonly used in place of tyrosine in parenteral nutrition, but human studies carried out to date indicate considerable amounts of it are excreted unchanged in the urine. NAT retention has not been well studied in parenterally fed adults.

METHODS

NAT retention was measured in 13 adults receiving continuous parenteral nutrition with Aminosyn II 15% (Abbott Laboratories, Abbott Park, IL).

RESULTS

Approximately 35% of administered NAT was excreted unchanged in the urine, with no important effect of infusion rate, N balance, or level of renal function on this value. Sufficient NAT was retained that the prescription of 1 g total amino acids/kg x day(-1) using this product exceeded the combined recommended dietary allowance for aromatic amino acids

CONCLUSION

As used in the clinical setting, the phenylalanine and NAT composition of Aminosyn II is sufficient to meet the combined aromatic amino acid needs of adults with normal phenylalanine hydroxylase activity.

Lower handgrip strength at discharge from acute care hospitals is associated with 30-day readmission: A prospective cohort study

BACKGROUND

Malnutrition at admission, using various parameters, is associated with 30-day readmission. However, the association between 30-day readmission and nutritional parameters at discharge has not been studied.

METHOD

From a large cohort study (n = 1022), 413 patients with a length of stay of ≥7 days who had information on readmission and discharge location were included into the analysis. Their nutritional status at discharge was assessed by subjective global assessment, body mass index, albumin, nutritional risk index and handgrip strength. Data on demography, diagnoses and Charlson comorbidity index (CCI) were also collected. Missing data was handled using multiple imputations by chained equations. Association of nutrition related measures with 30 day readmission was tested in logistic regression models.

RESULTS

Of the 413 patients, 86 (20.8%) were readmitted within 30 days. The proportion of readmitted patients was higher for medical (42.2%) versus surgical patients (25.6%) (p = 0.005) and disease severity was higher in the readmission group with (median (q1, q3) CCI of 3 (2, 6) versus 2(1, 4) for no readmission (p = 0.009). Among the nutritional parameters assessed at discharge, only handgrip strength was significantly associated with 30-day readmission both in unadjusted and adjusted models. Stronger handgrip was associated with decreased chances for readmission where adjusted OR (95% CI) per unit increase were 0.95 (0.92, 0.99). Handgrip strength was not associated with disease severity assessed by CCI (p = 0.14) but was significantly associated with SGA (SGA A and B significantly different from SGA C: both p-values <0.001) after adjusting for age and gender.

CONCLUSION

Lower handgrip at discharge was associated with 30-day readmission. This assessment may be useful to detect patients at risk of readmission to better individualize discharge planning including nutrition care.

Boreal forest health and global change

The boreal forest, one of the largest biomes on Earth, provides ecosystem services that benefit society at levels ranging from local to global. Currently, about two-thirds of the area covered by this biome is under some form of management, mostly for wood production. Services such as climate regulation are also provided by both the unmanaged and managed boreal forests. Although most of the boreal forests have retained the resilience to cope with current disturbances, projected environmental changes of unprecedented speed and amplitude pose a substantial threat to their health. Management options to reduce these threats are available and could be implemented, but economic incentives and a greater focus on the boreal biome in international fora are needed to support further adaptation and mitigation actions.

The Integrated Nutrition Pathway for Acute Care (INPAC): Building consensus with a modified Delphi

Background

Malnutrition is commonly underdiagnosed and undertreated in acute care patients. Implementation of current pathways of care is limited, potentially as a result of the perception that they are not feasible with current resources. There is a need for a pathway based on expert consensus, best practice and evidence that addresses this crisis in acute care, while still being feasible for implementation.

Methods

A modified Delphi was used to develop consensus on a new pathway. Extant literature and other resources were reviewed to develop an evidence-informed background document and draft pathway, which were considered at a stakeholder meeting of 24 experts. Two rounds of an on-line Delphi survey were completed (n = 28 and 26 participants respectively). Diverse clinicians from four hospitals participated in focus groups to face validate the draft pathway and a final stakeholder meeting confirmed format changes to make the pathway conceptually clear and easy to follow for end-users. Experts involved in this process were researchers and clinicians from dietetics, medicine and nursing, including management and frontline personnel.

Results

80 % of stakeholders who were invited, participated in the first Delphi survey. The two rounds of the Delphi resulted in consensus for all but two minor components of the Integrated Nutrition Pathway for Acute Care (INPAC). The format of the INPAC was revised based on the input of focus group participants, stakeholders and investigators.

Conclusions

This evidence-informed, consensus based pathway for nutrition care has greater depth and breadth than prior guidelines that were commonly based on systematic reviews. As extant evidence for many best practices is absent, the modified Delphi process has allowed for consensus to be developed based on better practices. Attention to feasibility during development has created a pathway that has greater implementation potential. External validation specifically with practitioner groups promoted a conceptually easy to use format. Test site implementation and evaluation is needed to identify resource requirements and demonstrate process and patient reported outcomes resulting from embedding INPAC into clinical practice.

Nutritional assessment: comparison of clinical assessment and objective variables for the prediction of length of hospital stay and readmission

BACKGROUND

Nutritional assessment commonly includes multiple nutrition indicators (NIs). To promote efficiency, a minimum set is needed for the diagnosis of malnutrition in the acute care setting.

OBJECTIVE

The objective was to compare the ability of different NIs to predict outcomes of length of hospital stay and readmission to refine the detection of malnutrition in acute care.

DESIGN

This was a prospective cohort study of 1022 patients recruited from 18 acute care hospitals (academic and community), from 8 provinces across Canada, between 1 July 2010 and 28 February 2013. Participants were patients aged ≥18 y admitted to medical and surgical wards. NIs measured at admission were subjective global assessment (SGA; SGA A = well nourished, SGA B = mild or moderate malnutrition, and SGA C = severe malnutrition), Nutrition Risk Screening (2002), body weight, midarm and calf circumference, serum albumin, handgrip strength (HGS), and patient-self assessment of food intake. Logistic regression determined the independent effect of NIs on the outcomes of length of hospital stay (<7 d and ≥7 d) and readmission within 30 d after discharge.

RESULTS

In total, 733 patients had complete NI data and were available for analysis. After we controlled for age, sex, and diagnosis, only SGA C (OR: 2.19; 95% CI: 1.28, 3.75), HGS (OR: 0.98; 95% CI: 0.96, 0.99 per kg of increase), and reduced food intake during the first week of hospitalization (OR: 1.51; 95% CI: 1.08, 2.11) were independent predictors of length of stay. SGA C (OR: 2.12; 95% CI: 1.24, 3.93) and HGS (OR: 0.96; 95% CI: 0.94, 0.98) but not food intake were independent predictors of 30-d readmission.

CONCLUSIONS

SGA, HGS, and food intake were independent predictors of outcomes for malnutrition. Because food intake in this study was judged days after admission and HGS has a wide range of normal values, SGA is the single best predictor and should be advocated as the primary measure for diagnosis of malnutrition. This study was registered at clinicaltrials.gov as NCT02351661.

Predictors of dietitian consult on medical and surgical wards

BACKGROUND & AIM

Guidelines promote dietitian consult (DC) for nutrition support. In Canada, dietitians are involved in the assessment of malnutrition and provide specialized dietary counseling. It is unknown however, what leads to a DC for patients fed orally. This study identifies independent predictors for a DC and determines what is the proportion of malnourished patients seeing a dietitian.

METHODS

The Canadian Malnutrition Task Force conducted a prospective cohort study in medical and surgical wards of 18 Canadian hospitals. 947 patients who did not receive enteral or parenteral nutrition were analyzed. At admission, subjective global assessment (SGA), body mass index, patient demography were collected. During hospitalization clinical data, including dietary intake and presence of a DC were obtained. Multivariate logistic regression was completed with dietitian consult ≤ 3 days and 4 + days as the outcome variables.

RESULTS

The prevalence of malnutrition (SGA B + C) was 45%. Dietitians were consulted for 23% of patients, and of these consults 44% were well nourished (SGA-A), 37% were mildly/moderately malnourished (SGA-B), and 19% were severely malnourished (SGA-C). DC missed 75% of the SGA-B and 60% of SGA-C patients. Predictors of consultation within 3 days of hospitalization were: renal diet (OR 5.75) modified texture diet (OR 5.38), metabolic diagnosis (3.91), ONS use pre-admission (OR 2.33), severe malnutrition (SGA-C, OR 1.88) and age (OR 0.98). Predictors for 4 + days were: dysphagia (OR 11.4), a new medical diagnosis (OR 2.3), severe malnutrition (OR 2.17), constipation (OR 2.16), more than one diagnosis (OR 1.8), antibiotic use (OR 1.6), and male gender (OR 1.6). Consuming < 50% of food in the first week was not a predictor as only 19% of those with low intake had a DC at 4 + days.

CONCLUSIONS

Overall predictors of DC were appropriate but SGA B and C patients and those eating <50% were missed. Screening at admission with algorithms of care that include referral to the dietitian are needed to improve the process of nutrition care.

Nurses' Perceptions Regarding the Prevalence, Detection, and Causes of Malnutrition in Canadian Hospitals: Results of a Canadian Malnutrition Task Force Survey

OBJECTIVES

Given the high prevalence of malnutrition in hospitalized patients, nurses frequently encounter patients with significantly impaired nutrition status. The objective of this study was to determine nurses' attitudes and perceptions regarding the prevalence, detection, and causes of malnutrition in Canadian tertiary care and community hospitals.

MATERIALS AND METHODS

In this descriptive study, a survey that focused on guidelines for nutrition support of hospitalized patients was completed by Canadian nurses working on medical and surgical wards in 11 hospitals participating in the Canadian Malnutrition Task Force study.

RESULTS

The survey was completed by 346 of 723 nurses (response rate 48%). Over 50% of nurses underestimated the documented prevalence of malnutrition in hospitalized patients. Nurses considered identification of malnourished patients very relevant (mean 8.4 on a 10-point scale) and would integrate a 3-question nutrition screen into their admission histories (92.5%). Nurses perceived lack of assistance with eating as a significant contributor to hospital malnutrition (17% felt this was a major contributor). While only 39% of nurses reported access to nutrition-related education, 92% were interested in receiving this form of updating.

CONCLUSIONS

Nurses consider nutrition assessment important and relevant and require access to training to improve their capacity to detect malnutrition in their patients. Nurses are vital to the nutrition care of hospitalized patients and are well positioned to screen for nutrition risk and assist in nutrition management. The role of nurses in nutrition care needs to be linked to hospital policy.

Physicians' perceptions regarding the detection and management of malnutrition in Canadian hospitals: results of a Canadian Malnutrition Task Force survey

OBJECTIVES

Since malnutrition is common in Canadian hospitals, physicians frequently encounter patients with significantly impaired nutrition status. The objective of this study was to determine physician attitudes and perceptions regarding the detection and management of malnutrition in Canadian hospitals.

MATERIALS AND METHODS

A survey based on a previously developed questionnaire that focused on guidelines for nutrition support of hospitalized patients was completed by Canadian physicians working on wards in the 18 hospitals participating in the Canadian Malnutrition Task Force study. Data were analyzed descriptively and according to ward (medical vs surgical) and hospital type (academic vs community).

RESULTS

The survey was completed by 428 of the 1220 physicians who were provided with a questionnaire and asked to participate (response rate 35%). While physicians believe that nutrition assessment should be performed at admission (364/419 [87%]), during hospitalization (363/421 [86%]), and at discharge (327/418 [78%]), most felt that this was not being done on a regular basis (admission, 140/423 [33%]; during hospitalization, 175/423 [41%]; at discharge, 121/424 [29%]). Similarly there was a gap between what was perceived to be the ideal management of hospital-related malnutrition and current practices. Physicians felt that the team's nutrition education and use of dietetic resources could be increased, and although their nutrition knowledge was limited, they felt that hospital-associated malnutrition was very relevant to the care they provided.

CONCLUSIONS

A multidisciplinary team is needed to address hospital malnutrition, and educational strategies that target physicians are needed to promote better detection and management throughout the hospital stay.

Growth of Multi Walled CNX Nanotubes: The Role of Synthesis Methods

Multi walled nitrogen doped nanotubes were synthesized using two different methods. The growth mechanism and nitrogen concentration of the nanotubes synthesized by both methods are discussed and studied. The morphology and nitrogen concentration of the nanotubes are seen to strongly depend on the synthesis methods. The results are based on detailed high resolution transmission electron microscopy (HRTEM) data coupled with electron energy loss spectroscopy (EELS).

Production of Fullerenes from Solar Energy

The high intensity of solar radiation, obtained with the Odeillo (France) solar furnace facilities, is used to vaporize graphite in inert gas atmosphere. The soot obtained contains C60, C70 and other heavier fullerenes. We discuss the possibility of increasing the evaporation rate of graphite and the yield of soot with this technique. From our last experiments, we obtain a first estimate of the soluble fullerene yield Y ( greater than 12%) and we have shown that 13C enriched fullerenes can be easily produced by this process.

Screening and therapy for malnutrition and related gastro-intestinal disorders in systemic sclerosis: recommendations of a North American expert panel

OBJECTIVES

To develop a set of recommendations for clinicians caring for patients with systemic sclerosis (SSc) to guide their approach to the patient with malnutrition and possible malabsorption.

METHODS

The Canadian Scleroderma Research Group convened a meeting of experts in the areas of nutrition, speech pathology, oral health in SSc, SSc and gastroenterology to discuss the nutrition-GI paradigm in SSc. This meeting generated a set of recommendations based on expert opinion.

RESULTS

Physicians should screen ALL patients with SSc for malnutrition. The physician should ask a series of questions that pertain to GI involvement. Patients who screen positive for malnutrition should be referred to a dietitian and gastroenterologist. Referral to a patient support group should be considered and if screening reveals oral health problems, referral to a dentist, preferably with expertise in treating patients with SSc, should be done. All SSc patients should weigh themselves monthly and report any sudden significant changes in weight. They should be assessed by a rheumatologist once a year for signs of malnutrition.

CONCLUSIONS

Malnutrition may be common in SSc and a multidisciplinary approach is important.

[Intraoperative transesophageal echocardiography to guide removal of a hypernephroma with vena cava and right atrial extension]

We describe the case of a 70-year-old man who underwent resection of a right hypernephroma with vena caval and right atrial extension with continuous monitoring by transesophageal echocardiography. The monitoring technique brought important advantages, providing images that facilitated anatomical and functional evaluation of cardiac structures without obstructing the surgical field. Images of the heart and great vessels obtained in real time allowed the surgeon to make operative decisions based on accurate assessment of the cephalad extension of the tumor to the right chambers. Transesophageal echocardiography also allowed the anesthesiologist to monitor hemodynamic status throughout surgery and watch for tumoral emboli. The imaging technique proved to be highly useful for both anesthetic and surgical management of the patient.

Synthesis of highly nitrogen-doped multi-walled carbon nanotubes

We present a new synthesis route for nitrogen doped carbon nanotubes (CNx) based on the aerosol method. Tubes with a record high concentration of nitrogen (approximately 20 atom%) have been synthesized, confirmed by electron energy loss spectroscopy (EELS). A strong correlation between the N/C ratio and morphology of the tubes is observed and discussed.

Increase in free radicals on UHMWPE hip prostheses components due to inflamed synovial cell products

Oxidative degradation of artificial UHMWPE joint implants caused by gamma-ray sterilization is thought to be responsible for the production of wear debris resulting in adverse tissue responses. On the other hand, it is well known that inflammation is associated with generation, by inflammatory cells, of free radicals (H(2)O(2) and NO) and destructive proteolytic enzymes (collagenases), which creates a strong oxidative environment. We hypothesized that when an UHMWPE implantation was performed in an inflammatory joint environment, the oxidative substances produced by inflamed synoviocytes could increase oxidative degradation of the polyethylene insert. We measured the amount of free radicals on conventional and on Duration-treated polyethylene samples by the electron spin resonance (ESR) technique before and after exposure of the samples to (1) inflamed synovial cell cultures; (2) normal synovial cell cultures; and (3) medium alone. We observed an increase in the number of free radicals on polyethylene samples after their immersion in cell cultures. Furthermore, it was observed that the increase of free radicals on polyethylene correlated with the degree of inflammation of synovial cells in culture.

Structural characterization of nanotube fibers by x-ray scattering

Nanotube fibers with diameters ranging between 10 and 100 microns were produced by a simple spinning process. These fibers were studied by x-ray scattering--a technique that allows good visualization of the composition as well as the alignment of the constituents. The fibers were found to be composed of bundles of single wall carbon nanotubes, poly(vinyl alcohol) polymer chains, graphitic objects, and Ni-based particles. The nanotubes and poly(vinyl alcohol) chains were preferentially oriented along the fiber axis.

13C NMR chemical shift of single-wall carbon nanotubes

We compute the magnetic shielding tensor within the London approximation and estimate the Knight shift of single-wall carbon nanotubes. Our results indicate that high resolution 13C NMR should be able to separate the metallic and insulator character of the nanotubes since a 11 ppm splitting is predicted from the respective resonances. As a model for disorder, bending, and defects in these structures, we investigate the magnetic response of nanotubes with finite size. We get a small line broadening coming from an intrinsic length dependent resonance effect. The nanotube packing is also studied and leads to a 20 ppm broadening which disappears under experimental high-resolution conditions.

Macroscopic fibers and ribbons of oriented carbon nanotubes

A simple method was used to assemble single-walled carbon nanotubes into indefinitely long ribbons and fibers. The processing consists of dispersing the nanotubes in surfactant solutions, recondensing the nanotubes in the flow of a polymer solution to form a nanotube mesh, and then collating this mesh to a nanotube fiber. Flow-induced alignment may lead to a preferential orientation of the nanotubes in the mesh that has the form of a ribbon. Unlike classical carbon fibers, the nanotube fibers can be strongly bent without breaking. Their obtained elastic modulus is 10 times higher than the modulus of high-quality bucky paper.