Production of Tetramethylpyrazine from Cane Molasses by Bacillus sp. TTMP20.

2,3,5,6-Tetramethylpyrazine (TTMP) is an active ingredient of Ligusticum wallichii Franch. It can be used in medicine and food fields. In this study, Bacillus sp. TTMP20 was applied to produce TTMP using cane molasses as a carbon source. After pretreatment with phosphoric acid, 170 mL/L treated molasses, combined with 10 g/L yeast powder, 30 g/L tryptone and 30 g/L (NH4)2HPO4 were used for fermentation. After 36 h, TTMP output reached the highest value of 208.8 mg/L. The yield of TTMP using phosphoric acid-treated molasses as carbon source was 145.59% higher than control. Under the sulfuric acid treatment process of molasses (150 g), the maximum yield of TTMP was 895.13 mg/L, which was 183.18% higher than that of untreated molasses (316.1 mg/L). This study demonstrated that molasses is a high-quality and inexpensive carbon source for the manufacture of TTMP, laying the groundwork for the future industrial production of TTMP.

Thyroid carcinosarcoma masquerading as a paraesophageal abscess in a Cane Corso dog.

A 12-year-old castrated male Cane Corso dog was presented with cervical swelling, lethargy, anorexia, and cough. An extensive neck mass with necrotic cysts was observed, severely adherent to surrounding tissues. Based on diagnostic imaging including ultrasound, computed tomography, and fine-needle aspiration cytology, paraesophageal abscess was tentatively diagnosed. However, after the mass was surgically removed, a diagnosis of thyroid carcinosarcoma composed of neoplastic cell populations with epithelial and mesenchymal origins was made via histopathology and immunohistochemistry. The dog died of a recurrent mass with pulmonary metastasis 105 d after surgery. This report describes a rare type of canine thyroid cancer, thyroid carcinosarcoma, preoperatively masquerading as an abscess and postoperatively confirmed by histopathology. Key clinical message: Thyroid carcinosarcoma, despite its rarity in dogs, should be included in the differential diagnoses of cervical mass especially with an aggressive progression.

Carcinosarcome thyroïdien déguisé en abcès paraoesophagien chez un chien Cane Corso. Un chien Cane Corso mâle castré de 12 ans a été présenté avec de l'enflure cervicale, de la léthargie, de l'anorexie et une toux. Une masse étendue du cou avec des kystes nécrotiques a été observée, adhérente fortement aux tissus environnants. Sur la base de l'imagerie diagnostique comprenant l'échographie, la tomodensitométrie et la cytologie par aspiration à l'aiguille fine, un abcès paraoesophagien a été provisoirement diagnostiqué. Cependant, après l'ablation chirurgicale de la masse, un diagnostic de carcinosarcome thyroïdien composé de populations de cellules néoplasiques d'origine épithéliale et mésenchymateuse a été posé par histopathologie et immunohistochimie. Le chien est décédé d'une masse récurrente avec métastase pulmonaire 105 jours après la chirurgie. Ce rapport décrit un type rare de cancer de la thyroïde canine, le carcinosarcome thyroïdien, se faisant passer pour un abcès en préopératoire et confirmé en postopératoire par histopathologie.Message clinique clé:Le carcinosarcome thyroïdien, malgré sa rareté chez le chien, doit être inclus dans les diagnostics différentiels de masse cervicale surtout à évolution agressive.(Traduit par Dr Serge Messier).

Cane Molasses Derived N-Doped Graphene Quantum Dots: Dynamic Quenching Synergistically Photoinduced Electron Transfer for the Instant Detection of Nitrofuran Antibiotics.

The development of a highly selective, simple, and rapid detection method for nitrofuran antibiotics (NFs) is of great significance for food safety, environmental protection, and human health. To meet these needs, in this work, cyan-color highly fluorescent N-doped graphene quantum dots (N-GQDs) were synthesized using cane molasses as the carbon source and ethylenediamine as the nitrogen source. The synthesized N-GQDs have an average particle size of 6 nm, a high fluorescence intensity with 9 times that of undoped GQDs, and a high quantum yield (24.4%) which is more than 6 times that of GQDs (3.9%). A fluorescence sensor based on N-GQDs for the detection of NFs was established. The sensor shows advantages of fast detection, high selectivity, and sensitivity. The limit of detection for furazolidone (FRZ) was 0.29 µM, the limit of quantification (LOQ) was 0.97 µM, and the detection range was 5-130 µM. The fluorescence quenching mechanism of the sensor was explored by fluorescence spectroscopy, UV-vis absorption spectroscopy, Stern-Volmer quenching constant, Zeta potential, UV-vis diffuse reflectance spectroscopy, and cyclic voltammetry. A fluorescence quenching mechanism of dynamic quenching synergized with photoinduced electron transfer was revealed. The developed sensor was also successfully applied for detecting FRZ in various real samples, and the results were satisfactory.

Enhanced docosahexaenoic acid production from cane molasses by engineered and adaptively evolved Schizochytrium sp.

Cane molasses (CM) is a sugar-rich agro-industrial byproduct. The purpose of this study is to synthesize docosahexaenoic acid (DHA) in Schizochytrium sp. by using CM. The single factor analysis showed that sucrose utilization was the main factor limiting the utilization of CM. Therefore, the endogenous sucrose hydrolase (SH) was overexpressed in Schizochytrium sp., which enhanced the sucrose utilization rate 2.57-fold compared to the wild type. Furthermore, adaptive laboratory evolution was used to further improve sucrose utilization from CM. Comparative proteomics and RT-qPCR were used out to analyze the metabolic differences of evolved strain grown on CM and glucose, respectively. Finally, a constant flow rate CM feeding strategy was implemented, whereby the DHA titer and lipid yield of the final strain OSH-end reached 25.26 g/L and 0.229 g/g sugar, respectively. This study demonstrated the CM is a cost-effective carbon source for industrial DHA fermentation.

Exploring the acceptability of the 'smart cane' to support mobility in older cancer survivors and older adults: A mixed methods study.

INTRODUCTION: Approximately 25% of older cancer survivors (i.e., ≥ 65 years, with cancer history) use ≥1 mobility device, surpassing usage by other older adults. Few tools exist for older "survivors" to regain function or follow lifestyle recommendations. Our goal was to explore opportunities to leverage technology-enabled mobility devices, such as the "smart cane," to support mobility goals in these survivors. The research objective was to assess perceptions related to acceptability, usability and preferences of participants regarding technology-enabled mobility devices in everyday life. MATERIALS AND METHODS: We used a convergent mixed-methods design, analyzing quantitative data followed by qualitative focus groups. A pre-survey derived from the Senior Technology Acceptance Model assessed the acceptability of technology-enabled devices among participants, who also participated in one of three focus groups delivered via Zoom. The Zoom sessions included facilitated 90-min discussions and video demonstration of the smart cane. Focus group sessions were recorded and transcribed verbatim and thematic content analysis was conducted. RESULTS: We recruited 12 older US survivors. Participants were 58% female, aged 68-86, and 16% non-White. From a pre-survey of participants, 83% said that they liked the idea of technology-enhanced mobility device and 100% said they thought they could be skillful at using a technology-enabled device if training was provided. Though participants were enthusiastic about the smart cane overall and felt the smart cane supported independence for older adults, the themes revealed concerns about safety, accessibility and technology support, as well as the concern for negative impact on self-image due to use of a mobility device. There was a strong preference for working with clinical professionals as the most trusted sources for referrals, if a smart cane was suggested. DISCUSSION: Older survivors in our sample found the smart cane very acceptable, and supportive of independence for older adults with cancer and other conditions. Participants also provided many insights that revealed additional research needed to support access, safety and usability for older adults, older survivors and caregivers, especially by partnering with clinical professionals.

Synthesis of Hyper-cross-linked Nonpolar Polystyrene Divinylbenzene Resins by Pendent Vinyl Groups and Application to the Decolorization of Cane Molasses.

Cane molasses is a by-product of sugar industry. It is widely used in fermentation field, but pigment compounds affect its further application. In this study, nonpolar hyper-cross-linked adsorption resins (HCARs) were synthesized by pendent vinyl groups cross-linking reaction, and were applied to decolorization of molasses. The correlation between the structure and the decolorization performance of HCARs was studied, and the results showed that the Brunauer-Emmett-Teller (BET) surface area and the pore volume of the resin significantly increased to 574.4 m2·g-1 and 1.40 cm3·g-1 after the Friedel-Crafts alkylation reaction with a catalyst dosage of 2.25% at 343 K for 7 h. Furthermore, the decolorization rate of molasses by the HCAR was 74%, and recycle decolorization performance of the resin was stable. The adsorption kinetics results showed that the pseudo-second-order dynamic model could more realistically reflect the decolorization mechanism of molasses on HCARs, and liquid film diffusion is the main rate-limiting step. The results of fixed-bed experiments show that D-ST-DVB resin has a good decolorization effect and recycling ability. Therefore, it is a feasible strategy for the decolorization of molasses with nonpolar HCAR.

Laser Sensing and Vision Sensing Smart Blind Cane: A Review.

Laser sensing and vision sensing smart canes can improve the convenience of travel for the visually impaired, but for the present, most of the system functions of laser sensing and vision sensing smart canes are still defective. Guide equipment and smart blind canes are introduced and classified first, and the smart blind canes based on vision sensing, laser sensing and laser vision sensing are investigated, respectively, and the research status of laser vision sensing smart blind canes is sorted out. The advantages and disadvantages of various laser vision sensing smart blind canes are summarized, especially the research development of laser vision fusion as the core of new smart canes. The future development prospects of laser vision sensing smart blind cane are overviewed, to boost the development of laser vision sensing smart blind cane, to provide safe and efficient travel guarantee for the visually impaired.

Effects of cane use on the kinematic and kinetic of lower-extremity joints in inexperienced users.

The cane is commonly prescribed for the elderly to maintain balance and enhance independent mobility. However, improper use of cane can increase the risk of falling. Understanding the characteristics of cane gait is critical for better establishing proper cane usage norms. The paper aimed to investigate effects of cane use on kinematics and kinetics of lower extremities in the elderly and the young to guide the development of adaptive cane gait. Twenty participants (10 elder and 10 young) were recruited and walked at a self-comfortable speed or with a cane in a two-point gait. The spatiotemporal gait parameters, hip/knee/ankle joint angles and ground reaction force (GRF) were statistically analyzed using MANOVAs to assess the effects of age and cane. Using the cane significantly decreased step length, cadence and speed and increased step time in both age groups. Age and cane had significant effects on ankle plantarflexion angle in initial swing phase (APA-ISw). In cane gait, the peaks of vertical GRF(V-GRF) and anterior-posterior GRF (AP-GRF) in bilateral lower extremities significantly decreased, and the troughs of right V-GRF significantly increased for both groups. These results suggest that using a cane does interfere with the natural gait of the user and insufficient ankle plantarflexion in initial swing phase (ISw) and reduced AP-GRF may be two key risk factors contributing to cane gait instability. Therefore, the users should consider actively increasing ankle plantarflexion in ISw to avoid deteriorating gait performance due to over-reliance on the cane.

Osteology and radiographic anatomy of the thoracic limb of the greater cane rat (Thryonomys swinderianus).

The greater cane rat (Thryonomys swinderianus) is mainly distributed in the humid and sub-humid regions of the sub-Saharan Africa. It is believed to be the second largest African rodent. The aim of this study was to describe the normal osteology and radiographic anatomy of the thoracic limb of the greater cane rat as a reference for teaching, clinical use, anatomical studies and biomedical research. Five intact dead greater cane rats were used for radiographic examination. Radiographic findings were correlated with bone specimens. The clavicle was seen in all animals. The scapula was wide with well-developed acromion and coracoid process. The major and minor tubercles did not extend higher than the head of the humerus. The deltoid tuberosity was very prominent. The medial epicondyle was larger than its lateral counterpart, and the supratrochlear foramen was present. The radial tuberosity was further distally located. The ulnar head was well-developed, and the olecranon tuber was square-shaped. The distal physes for the radius and ulna appeared transverse. The carpus had eight bones. The manus presented with five widely spread digits. The first digit was reduced in size and placed such that the dorsal and palmar surfaces face almost medial and lateral, respectively. Additionally, two rudimentary digits were seen. Variations exist in the normal osteology and radiographic anatomy of the thoracic limb in different species. Knowledge of the normal osteology and radiographic anatomy of the thoracic limb of individual species is important for species identification and diagnosis of musculoskeletal diseases involving the thoracic limb.

IoT Enabled Intelligent Stick for Visually Impaired People for Obstacle Recognition.

This paper presents the design, development, and testing of an IoT-enabled smart stick for visually impaired people to navigate the outside environment with the ability to detect and warn about obstacles. The proposed design employs ultrasonic sensors for obstacle detection, a water sensor for sensing the puddles and wet surfaces in the user's path, and a high-definition video camera integrated with object recognition. Furthermore, the user is signaled about various hindrances and objects using voice feedback through earphones after accurately detecting and identifying objects. The proposed smart stick has two modes; one uses ultrasonic sensors for detection and feedback through vibration motors to inform about the direction of the obstacle, and the second mode is the detection and recognition of obstacles and providing voice feedback. The proposed system allows for switching between the two modes depending on the environment and personal preference. Moreover, the latitude/longitude values of the user are captured and uploaded to the IoT platform for effective tracking via global positioning system (GPS)/global system for mobile communication (GSM) modules, which enable the live location of the user/stick to be monitored on the IoT dashboard. A panic button is also provided for emergency assistance by generating a request signal in the form of an SMS containing a Google maps link generated with latitude and longitude coordinates and sent through an IoT-enabled environment. The smart stick has been designed to be lightweight, waterproof, size adjustable, and has long battery life. The overall design ensures energy efficiency, portability, stability, ease of access, and robust features.

Intelligent Gait Analysis and Evaluation System Based on Cane Robot.

Gait analysis and evaluation are vital for disease diagnosis and rehabilitation. Current gait analysis technologies require wearable devices or high-resolution vision systems within a limited usage space. To facilitate gait analysis and quantitative walking-ability evaluation in daily environments without using wearable devices, a mobile gait analysis and evaluation system is proposed based on a cane robot. Two laser range finders (LRFs) are mounted to obtain the leg motion data. An effective high-dimensional Takagi-Sugeno-Kang (HTSK) fuzzy system, which is suitable for high-dimensional data by solving the saturation problem caused by softmax function in defuzzification, is proposed to recognize the walking states using only the motion data acquired from LRFs. The gait spatial-temporal parameters are then extracted based on the gait cycle segmented by different walking states. Besides, a quantitative walking-ability evaluation index is proposed in terms of the conventional Tinetti scale. The plantar pressure sensing system records the walking states to label training data sets. Experiments were conducted with seven healthy subjects and four patients. Compared with five classical classification algorithms, the proposed method achieves the average accuracy rate of 96.57%, which is improved more than 10%, compared with conventional Takagi-Sugeno-Kang (TSK) fuzzy system. Compared with the gait parameters extracted by the motion capture system OptiTrack, the average errors of step length and gait cycle are only 0.02 m and 1.23 s, respectively. The comparison between the evaluation results of the robot system and the scores given by the physician also validates that the proposed method can effectively evaluate the walking ability.

Action of silicon on the activity of antioxidant enzymes and on physiological mechanisms mitigates water deficit in sugarcane and energy cane plants.

Production of sugarcane and more recently of energy cane strengthen renewable bioenergy production capacity. However, droughts resulting from climate change have limited the production of these crops. One of the strategies to attenuate water deficit damage in these crops is the use of silicate, which contributes to plant physiology. This strategy is likely to increase water use efficiency, thus promoting crop sustainability. Notwithstanding, studies on this issue are still incipient. This study assesses whether Si applied via fertigation and foliar spraying in the seedling production phase and as a complement after seedling transplanting to the soil is efficient in attenuating water deficit in sugarcane and energy cane. The study further elucidates physiological and biochemical mechanisms involved in this process. For this, the authors conducted two experiments: one with sugarcane and the other with energy cane. Treatments were arranged in randomized blocks with 5 replications, in a 2 × 2 factorial scheme. Factors consisted of the absence (-Si) and presence of Si (+ Si) applied via fertigation and foliar spraying; and two water regimes: 70% (without water deficit) and 30% (severe water deficit) of the soil water retention capacity. Silicon was supplied during the formation phase of presprouted seedlings and during the transplanting of seedlings to pots filled with samples of Entisol (Quartzipsamment). In these pots, water regimes were induced from 7 to 160 days after transplanting. Severe water deficit reduced the water content and water potential of plants. This situation induced oxidative stress and impaired gas exchange and photosynthetic water use efficiency, reducing plant growth. Silicon supply via fertigation in association with foliar spraying in the seedling formation phase with complementation after transplanting was efficient in increasing Si accumulation in the plants. Silicon was effective in attenuating severe water deficit damage up to initial culm formation through mechanisms that maintain water and physiological balance by favoring the antioxidant defense system in sugarcane and energy cane plants.

[Guidelines: leash or walking stick?] / Richtlijnen: leiband of wandelstok?

Guidelines are undeniably of great value to practicing physicians, but there are also objections. Due to the multitude of guidelines, it is sometimes difficult to find the most appropriate and it is not always clear how well-founded recommendations are. In addition, guidelines can limit the freedom of action. Also, in individual patients - especially in the case of multimorbidity - recommendations from different guidelines can conflict with each other. Finally, drawing up guidelines takes a lot of time, which is at the expense of patient care, and conflicts of interest are difficult to avoid completely. It is therefore important to put the recommendations from guidelines into perspective: they are an aid to individual patient care, not a law. This perspective is also important in education, so that students are taught to use guidelines in a wise way. Finally, it is important to regularly evaluate recommendations and revise them if necessary.

Changes in cognitive-motor interference during rehabilitation of cane walking in patients with subacute stroke: A pilot study.

No previous research has examined cognitive-motor interference (CMI) repeatedly in patients with subacute stroke. This pilot study aimed to report on the changes over time in CMI in patients with stroke who have recently learned to walk with a cane. The assessment started as soon as the participants could walk independently with a quad cane, and was repeated up to six sessions as long as the cane was still used. The dual-tasking paradigm required participants to walk and perform continuous subtractions by 3s. Data were analyzed for 9 participants 33-127 days post-stroke. All 9 participants showed CMI in walking velocity at baseline and 8 of these showed improvement over time (Z = -2.547; p = 0.011). The improvement in CMI was associated with baseline dual-tasking performance (ρ = 0.600; p = 0.044), motor control ability (ρ = -0.695; p = 0.019), walking velocity (ρ = -0.767; p = 0.008), and functional mobility (ρ = 0.817; p = 0.004). All participants showed decrements in both tasks (mutual interference) at baseline, 1 evolved to decrements in walking velocity (cognitive-related motor interference), and 3 finally evolved to decrements in cognitive performance but increments in walking velocity (motor-priority tradeoff). In conclusion, during rehabilitation with cane walking in patients with subacute stroke, the dual-tasking paradigm revealed CMI and its improvements in the majority of participants. Greater improvement in CMI was moderately to strongly associated with worse baseline performance of many variables. The evolution of the CMI pattern over time provides novel information relevant to neurological recovery.

Cane Vinasses Contain Bioactive Concentrations of Auxin and Abscisic Acid in Their Composition.

Currently, high doses of vinasse are employed for the fertigation of sugarcane with positive results on yield. Usually, this effect is related to the presence of mineral nutrients in its composition as well as to its action on soil properties. Consequently, the concentrations of minerals, organic acids, and other metabolites in vinasse are very well characterized. However, considering that cane vinasses are obtained from the treatment of vegetal tissues, it is also possible that they might contain significant concentrations of phytoregulators that could have a relevant role in their beneficial action on yield. To investigate this hypothesis, we analyzed the main plant hormones in 22 samples of vinasse collected in different production sites of Brazil using HPLC-mass spectrometry. The results show that both ABA and IAA present concentrations in vinasse within the micromolar range, thus being potential active ingredients affecting plant development. In conclusion, the beneficial action of cane vinasses on sugarcane yield might involve, among other factors, the action of IAA and ABA on plant growth.

Semi-Quantitative Discrimination of Honey Adulterated with Cane Sugar Solution by an ETongue.

This study successfully applied a potentiometric E-tongue with 20 cross-selectivity lipidic polymeric membranes in the discrimination of three semi-quantitative groups, that represented the following intervals of honey adulteration percentage with cane sugar: 0 %; [0, 10]%; [10, 20]% of adulteration. We analysed five different types of Portuguese honey; five brands of cane sugar were added to the adulterated samples; a comparative analysis was then performed. Linear discriminant analysis coupled with a tabu search algorithm for feature selection was applied to the ETongue's analytical data to select the best model. A discriminant model with 12 sensors was obtained. This model classified correctly all samples in both in internal (train data, 15 samples) and external validation (test data,10 samples). Also, multiple linear regression with tabu search was applied to verify if ETongue's data would allow quantifying the honey's adulteration level. The results showed that it was possible to obtain a quantitative model but with unsatisfactory predictive performance in the test data group (external validation), giving, in general, values below the expected concentrations. E-tongue is a real-time green, flexible and low-cost analytical tool that requires minimum sample preparation and no special technical skills, being a promising tool for everyday application.

Mitochondrial genetic diversity of the Greater Cane rat (Thryonomys swinderianus) populations from the Eastern Arc Mountains ecosystem, Tanzania.

BACKGROUND: Management of most herbivorous small mammal species considered to be pests in Africa is still challenging partly because of the paucity of information on their biological traits that would help to manage their destructive impacts. This gap also precludes the potential for tapping species with potential food-value to improving the economy of rural communities through, for example, sustainable game farming programs in Africa. This study investigates the genetic diversity and population demography of the African Greater Cane rat (AGC), a rodent pest of crops and game species inhabiting two isolated blocks of the Eastern Arc Mountains (EAMs), Tanzania to contribute to the species management and conservation. METHODOLOGY AND RESULTS: We used non-invasive sampling techniques and DNA sequencing of the D-loop region of MtDNA (515bp) from 46 cane rats (Thryonomys swinderianus) samples to characterize the genetic diversity and structure of the species and potential population threats faced in natural habitats. We found 25 haplotypes:15 from Uluguru and 9 from Udzungwa mountains populations, containing 49 polymorphic regions (32 parsimoniously informative and 17 singleton sites). Haplotype diversity (range: 0.849-0.995) did not differ substantially across populations but the median haplotype diversity for Udzungwa South was overall lower than for other populations. Nucleotide diversity averaged 0.00641, 0.01528, 0.0111 and 0.01313, respectively for Udzungwa South, Udzungwa North, Uluguru Rural and Uluguru Urban, suggesting high genetic diversity within the four populations. Analysis of molecular variance (AMOVA) indicated significantly high genetic differences between the four populations (FST = 0.16, p = 0.00098) whereas neutrality test (FU's Fs) values were negative, indicating historical population expansion. Similarly, the Bayesian skyline analysis indicated a recent demographic expansion suggesting limited bottlenecks in the recent past in this population. CONCLUSIONS: Our results show the AGC population in EAMs consists of four distinct populations which have experienced a recent population expansion, especially among the urban population due perhaps to influence of urbanization process that may have favored assisted species movements across the rural-urban landscapes. Future research should focus on understanding impact of geographical isolation on the genetic structure and diversity of this species.

An IoT Machine Learning-Based Mobile Sensors Unit for Visually Impaired People.

Visually impaired people face many challenges that limit their ability to perform daily tasks and interact with the surrounding world. Navigating around places is one of the biggest challenges that face visually impaired people, especially those with complete loss of vision. As the Internet of Things (IoT) concept starts to play a major role in smart cities applications, visually impaired people can be one of the benefitted clients. In this paper, we propose a smart IoT-based mobile sensors unit that can be attached to an off-the-shelf cane, hereafter a smart cane, to facilitate independent movement for visually impaired people. The proposed mobile sensors unit consists of a six-axis accelerometer/gyro, ultrasonic sensors, GPS sensor, cameras, a digital motion processor and a single credit-card-sized single-board microcomputer. The unit is used to collect information about the cane user and the surrounding obstacles while on the move. An embedded machine learning algorithm is developed and stored in the microcomputer memory to identify the detected obstacles and alarm the user about their nature. In addition, in case of emergencies such as a cane fall, the unit alerts the cane user and their guardian. Moreover, a mobile application is developed to be used by the guardian to track the cane user via Google Maps using a mobile handset to ensure safety. To validate the system, a prototype was developed and tested.

Wearable Travel Aids for Blind and Partially Sighted People: A Review with a Focus on Design Issues.

The ability to travel (independently) is very important for participation in education, work, leisure activities, and all other aspects of modern life. Blind and partially sighted people experience a number of barriers to travel, including inaccessible information and environments, and consequently require support from technology or other people to overcome them. Despite the potential of advanced technologies and the development of electronic travel aids, the long cane and guide dog remains the most commonly used solutions. Wearable technologies are becoming increasingly popular. They have the particular advantage of keeping the hands free, thereby facilitating the use of a long cane, guide dog or another device at the same time. They also have the potential to change the ways in which users interact with the environment. The main contributions of this paper are surveying the current state-of-the-art of travel aids from a design perspective and investigating the following issues: (1) The important design issues in wearable travel aids and the extent to which they are taken into account in different devices; (2) The relationship, if any, between where and how travel aids are worn and their design, features and functions; (3) Limitations of existing devices, gaps in provision and future research directions, particularly with regard to meeting potential users' needs.