Fixation Time Research Articles

Acromial and Scapular Spine Fractures following Reverse Total Shoulder Arthroplasty—A Systematic Review of Fixation Constructs and Techniques

Fractures of the acromion and the scapular spine are established complications of reverse shoulder arthroplasty (RSA), and when they occur, the continuous strain by the deltoid along the bony fragments makes healing difficult. Evidence on treatment specific outcomes is poor, making the definition of a gold standard fixation technique difficult. The purpose of this systematic review is to assess whether any particular fixation construct offers improved clinical and/or radiographic outcomes. A systematic review of the literature on fixation of acromial and scapular spine fractures following RSA was carried out based on the guidelines of PRISMA. The search was conducted on PubMed, Embase, OVID Medline, and CENTRAL databases with strict inclusion and exclusion criteria applied. Methodological quality assessment of each included study was done using the modified Coleman methodology score to asses MQOE. Selection of the studies, data extraction and methodological quality assessment was carried out by two of the authors independently. Only clinical studies reporting on fixation of the aforementioned fractures were considered. Fixation construct, fracture union and time to union, shoulder function and complications were investigated. Nine studies reported on fixation strategies for acromial and scapular spine fractures and were therefore included. The 18 reported results related to fractures in 17 patients; 1 was classified as a Levy Type I fracture, 10 as a Levy Type II fracture and the remaining 7 fractures were defined as Levy Type III. The most frequent fixation construct in type II scapular spine fractures was a single plate (used in 6 of the 10 cases), whereas dual platin was the most used fixation for Levy Type III fractures (5 out of 7). Radiographic union was reported in 15 out of 18 fractures, whereas 1 patient (6.7%) had a confirmed non-union of a Levy Type III scapular spine fracture, requiring revision fixation. There were 5 complications reported, with 2 patients undergoing removal of metal and 1 patient undergoing revision fixation. The Subjective Shoulder Value and Visual Analogue Scale pain score averaged 75% and 2.6 points, respectively. The absolute Constant Score and the ASES score averaged 48.2 and 78.3 points, respectively. With the available data, it is not possible to define a gold standard surgical fixation but it seems that even when fracture union can be achieved, functional outcomes are moderate and there is an increased complication rate. Future studies are required to establish a gold standard fixation technique.

Drivers’ Eye Movement Characteristics in a Combined Bridge-Tunnel Scenario on a Mountainous Urban Expressway: A Realistic Study

Combined bridge-tunnel scenarios of driving on mountainous city expressways occur when bridges and tunnels frequently alternate during driving. The complex nature of these driving scenarios imposes crucial requirements on the drivers’ eye movement characteristics. This paper attempts to clarify these characteristics using descriptive statistics and the box graph method, registering the pupil diameter, blink duration, fixation, saccades, and fixation loci at different tunnel locations, bridges, and ramps. Realistic driving experiments were performed on the road segment spanning from the Nanchang tunnel to the Liujiatai tunnel freeway in Chongqing, China. Eye movement data were collected for 21 drivers. The experimental results showed that, while driving in the tunnel, the maximal pupil diameter of the participating drivers was approximately 4.0 mm as the driving mileage and the number of tunnels increased, and the maximal visual load on the drivers in the tunnel tended to be stable. At the second tunnel exit, the ramp, the middle section of the first bridge, and the third tunnel exit, the driving load was the highest, while the fixation duration was shorter for nighttime driving. The fixation duration was the longest for the diversion road of bridge B1 to the ramp during the day, and the fixation times were the longest at the beginning and end of the test road. The drivers more often paid attention to the speed dashboard while entering tunnels during daytime driving (compared with nighttime driving).

Efficient training approaches for optimizing behavioral performance and reducing head fixation time.

The use of head fixation has become routine in systems neuroscience. However, whether the behavior changes with head fixation, whether animals can learn aspects of a task while freely moving and transfer this knowledge to the head fixed condition, has not been examined in much detail. Here, we used a novel floating platform, the "Air-Track", which simulates free movement in a real-world environment to address the effect of head fixation and developed methods to accelerate training of behavioral tasks for head fixed mice. We trained mice in a Y maze two choice discrimination task. One group was trained while head fixed and compared to a separate group that was pre-trained while freely moving and then trained on the same task while head fixed. Pre-training significantly reduced the time needed to relearn the discrimination task while head fixed. Freely moving and head fixed mice displayed similar behavioral patterns, however, head fixation significantly slowed movement speed. The speed of movement in the head fixed mice depended on the weight of the platform. We conclude that home-cage pre-training improves learning performance of head fixed mice and that while head fixation obviously limits some aspects of movement, the patterns of behavior observed in head fixed and freely moving mice are similar.

Reduced cortical neuron number and neuron density in schizophrenia with focus on area 24: a post-mortem case–control study

Structural and functional abnormalities of the anterior cingulate cortex (ACC) have frequently been identified in schizophrenia. Alterations of von Economo neurons (VENs), a class of specialized projection neurons, have been found in different neuropsychiatric disorders and are also suspected in schizophrenia. To date, however, no definitive conclusions can be drawn about quantitative histologic changes in the ACC in schizophrenia because of a lack of rigorous, design-based stereologic studies. In the present study, the volume, total neuron number and total number of VENs in layer V of area 24 were determined in both hemispheres of postmortem brains from 12 male patients with schizophrenia and 11 age-matched male controls. To distinguish global from local effects, volume and total neuron number were also determined in the whole area 24 and whole cortical gray matter (CGM). Measurements were adjusted for hemisphere, age, postmortem interval and fixation time using an ANCOVA model. Compared to controls, patients with schizophrenia showed alterations, with lower mean total neuron number in CGM (− 14.9%, P = 0.007) and in layer V of area 24 (− 21.1%, P = 0.002), and lower mean total number of VENs (− 28.3%, P = 0.027). These data provide evidence for ACC involvement in the pathophysiology of schizophrenia, and complement neuroimaging findings of impaired ACC connectivity in schizophrenia. Furthermore, these results support the hypothesis that the clinical presentation of schizophrenia, particularly deficits in social cognition, is associated with pathology of VENs.

Attempts to Attract Eyesight in E-Commerce May Have Negative Effects.

E-commerce shop owners often want to attract user attention to a specific product to enhance the chances of sales, to cross-sell, or up-sell. The way of presenting a recommended item is as important as the recommendation algorithms are to gain that attention. In this study, we examined the following types of highlights: background, shadow, animation, and border, as well as the position of the item in a 5 × 2 grid in a furniture online store, and their relationships with user fixations and user interest. We wanted to verify the effects highlighting had on attracting user attention. Various levels of intensity were considered for each highlight: low, medium, and strong. Methods used for data collection were both implicit and explicit: eye tracking, tracking cart's contents, and a supplementary survey. Experimental results showed that a low-intensity background highlight should be the first-choice solution to best attract user attention in the presented shopping scenario, resulting in the best fixation times and most users' selections. However, in the case of the highest-intensity animations, highlighting seemed to have negative effects; despite successful attempts to attract eyesight and a long fixation time, users did not add the highlighted products to cart.

The Esthetics of the Nasolabial Fold and Age in the Elderly Via Eye-Tracking.

Facial aging is associated with the loss of soft tissue fullness. Perioral signs of facial aging can add years to individuals' appearances and even affect their facial expressions in smiling and nonsmiling images. To evaluate the influence of the nasolabial fold on the visual perception of esthetics and age in the elderly, eye-tracking and a visual analog scale were used. This study applied a cross-sectional study using 40 laypeople. Facial images of an elderly woman were modified to include facial expression lines such as nasolabial folds and marionette lines with no folds, intermediate, and accentuated depths folds. Eye tracking was implemented to measure the average number of fixations. Heat maps and dot maps were generated using eye-tracking software. A visual analog scale of attractiveness and age perception questionnaire were also incorporated into the study. Statistical analysis was performed using a significance of (P<0.05). The majority of visual attention was paid to the eye and mouth areas. In the images with no folds, the right eye attracted a greater degree of fixation. In the images in which nasolabial folds were accentuated, the mouth area served as an area of high fixation. No statistical difference was observed between the groups in which smiling images were viewed. Nonsmiling images demonstrated significant differences between groups for variables including time until first fixation, complete fixation time, and number of fixations on the eyes and hemifaces. Old age and diminished attractiveness were associated with attenuated nasolabial folds, especially in nonsmiling images. The facial lines and expressions of elderly female individuals were assessed by laypeople using eye-tracking, showing that the deeper one's nasolabial folds, the more aged and less attractive one appears, especially in nonsmiling images. Smiling pictures were perceived to be more attractive and youthful; these perceptions should be considered in the search for improved esthetic results, whether in dental or facial esthetic treatments.

Comparison of Post-Operative Results of Early Versus Delayed Open Reduction and Internal Fixation of Isolated Mandibular Fractures

Objective: To evaluate the impact of treatment time of open reduction internal fixation of mandibular fractures in post-operative complications.&#x0D; Study Design: Quasi-experimental study.&#x0D; Place and Duration of Study: Oral and Maxillofacial Surgery, Armed Forces Institute of Dentistry, Combined Military Hospital, Rawalpindi Pakistan, from Jan to Jun 2019.&#x0D; Methodology: A hundred and four patients with isolated mandibular fractures diagnosed clinically and radiologically were included in the study. Group-I was the early Group consisting of cases reported under 72 hours, and Group-II was the delayed Group consisting of patients after 72 hours and within fourteen days. Treatment outcomes were assessed and compared for all patients based on clinical parameters in the post-operative period during follow-up.&#x0D; Results: One hundred and four patients with mandibular fractures were treated with open reduction internal fixation. On a periodic follow-up of 6 months, all patients were evaluated for malocclusion, surgical site infection, hardware exposure, and non-union complications. Group-I showed six patients (11.70%) with malocclusion, whereas three patients (6.10%) in Group-II had malocclusion (p-value=0.295). Surgical site infection was present in 2(3.84%) patients in Group-I and 3(5.76%) patients in Group-II (p-value=0.647). There was no case of non-union and three patients (5.76%) of hardware exposure in Group-I and two patients (3.84%) in Group-II (p-value=0.647). No statistically significant increase in post-operative complications in malocclusion, surgical site infection, hardware exposure, and non-union was found in Group-II with comparison Group-I.&#x0D; Conclusion: Delay in the surgical intervention of mandible fractures does not lead to increased post-operative complications.&#x0D;

Using Eye-Tracking for Traffic Control Signage Design at Highway Work Zone

&#x0D; This paper discusses the application of Eye Tracking (ET) technologies for researchers to understand a driver’s perception of signage at the highway work zone. Combining ET within a screen-based motion pictures and a driving simulator, the team developed an analytical method that allowed designers to evaluate signage design. Two experiments were set up to investigate how signage design might affect a driver’s visual attention and interaction under various environmental complexities and glare conditions. The study explores the visual perception related to several spatial features, including signage modality, scene complexity, and color schemes. The ET method utilizes total fixation time and time to first fixation data to evaluate the effectiveness of signage presented through screen-based video and a driving simulator.

아이트랙커를 이용한 CMS (Camera Monitor System)과 후사경에 대한 비교 평가

Objective: The evaluation of driving performance is conducted on the CMS and the rear view of the side during the driving of the actual vehicle, and an improvement plan is proposed for CMS.BRBRBackground: Rearview mirrors play an essential role in the vehicle (especially in cars) while taking reverse, parking, and changing lanes. Current cars are equipped with many safeguards (cruiser functions, autonomous driving, lane departure prevention, etc.) to help drivers. The camera monitoring system (CMS) has been used as one of the rearview mirrors in recent times. However, the visual acuity while using CMS is not considered enough in ergonomics research.BRBRMethod: Thirty subjects without any eye diseases took part in this study. An experiment was performed with two vehicles installed with a rearview mirror and another with CMS. To compare the two conditions fixation time and saccade time were evaluated.BRBRResults: Overall, using CMS required lower fixation time and saccade time than the conventional rearview mirror. All these results showed that CMS requires less cognitive load than rearview mirrors.BRBRConclusion: There were problems with glare and distance, and there was no sign of caution in the available rearview mirror in CMS. BRBRApplication: If the problems and cautions about future glare and distance are solved and applied, it will be the design of a safer CMS.

The Outcome of Placing the Medial K-wire First and Then the Lateral K-wire in Treating Supracondylar Humerus Fractures in Children Treated by Closed Reduction.

Background Displaced Gartland type III and IV supracondylar fractures are difficult to reduce and invariably require closed pining. After closed reduction, taking the anteroposterior (AP) view does not present any problem but when the elbow is placed in flexion and the limb is rotated internally to take a lateral view, the reduction is invariably lost. However, the reduction stays when the arm is rotated outwards, keeping the medial condyle up. This stimulates the idea of whether the medial pin can be placed first and then the two lateral pins to stabilize the fracture. It is very frustrating for young orthopedic surgeons to see reduction getting lost during internal rotation after first doing lateral pinning. There is no clear guideline on which side should be fixed first. Hypothesis We hypothesized that placing the medial pin first maintains the reduction and facilitates the subsequent placing of lateral pins without the loss of reduction. Materials and methods A total of 170 children with displaced supracondylar humerus fractures were included in the study. A total of 120 children were grouped in the medial wire first group, and 50 were placed in the lateral wire first group, which was the control group. The mean age of the children was 7.5 years (range 2-13 years). The gender ratio (M: F) was 5:3; the left elbow was involved in 68% of the injuries, whereas the right elbow was involved in 32% of the injuries. All 170 children had an extension-type injury, with 91 (53.5%) fractures being Gartland type III and 79 (46.45%) fractures being type IV. Results Results were recorded as per Flynn's criteria. At the end of two years of follow-up, the children in the medial wire first group 117 (97.5%) showed excellent resultsand three (2.5%) children showed good results, whereas, in the lateral wire first group, 48 (96%) children showed excellent results and two (3.8%) children showed good results. There was a significant difference in the mean surgical time of 20.11±15.43 minutes in the medial wire first group vs 41.23±19.65 minutes in the lateral first group (p = 0.0021). None of the children developed permanent ulnar nerve palsy. Conclusions Placing the medial K-wire first rather than the conventional placing of the lateral wire first helps in maintaining the reduction and allows for the subsequent placement of lateral K-wires without losing the reduction, thus minimizing fixation time and producing good results.

Comparative study of monolateral and circular fixator in the treatment of infectious tibial nonunion

To compare treatment effect of monolateral and circular external fixator in infectious tibial nonunion and to explore external fixation structure with better osteogenic ability and fewer complications. A retrospective analysis was performed on 150 patients with infectious tibial nonunion admitted from January 2010 to December 2014. Patients who met the inclusion and exclusion criteria were divided into monolateral fixator group and circular fixator group according to the type of external fixation. Demographic and perioperative data of the two groups were collected. New bone quality was assessed by pixels ratio, treatment effect was assessed by complications. Notes for treatment was explored by case analysis. A total of 64 patients with infectious mid-tibial nonunion were included, 26 in monolateral fixator group and 38 in circular fixator group. There was no difference in demographic data between two groups. The pixel ratio of new bone between two groups was from 0.91 to 0.97 with an average of (0.94±0.03), and from 0.93 to 0.97 with an average of(0.95±0.02), respectively, with no statistical significance (P>0.05). The external fixation index was from 34.1 to 50.6 with an average of (42.3±8.3) days /cm in monolateral fixator group and from 44.5 to 56.1 with an average of (45.8±10.3) days/cm in the circular fixator group, and the difference was not statistically significant (P>0.05). There were 7 cases (26.9%) of complications in monolateral fixator group and 5 cases (13.2%) in circular fixator group, the difference was not statistically significant (P>0.05), but 5 cases of foot ptosis in monolateral fixator group and none in circular fixator group. The time of weight bearing in monolateral fixator group was later than that in circular fixator group, and the difference was statistically significant (P<0.05). Monolateral and circular fixators can achieve equivalent bone formation in the treatment of infected tibial nonunion. Circular fixator is recommended for patients with severe osteoporosis or concomitant medical diseases requiring early weight bearing. Hydroxyapatite coated screws are recommended if a monolateral external fixator is selected when the expected enlarged length is long and the fixation time is long and close monitoring of the ankle movement is required to avoid foot droop.

Differences in Visual Attraction between Historical Garden and Urban Park Walking Scenes

Previous studies on visual perception and landscape element preference have mainly focused on urban green spaces such as parks and forests; the visual attraction potential of historical gardens has been less explored. Based on the analysis framework of the visual landscape experience, this study employed normalized eye-tracking data and preference questionnaires to compare the difference in visual attraction of typical walking scenes between historical gardens and urban parks. The results showed that in terms of landscape elements, the variation fluctuation of the fixation time on various landscape elements by participants viewing historical garden walking scenes (HGWSs) was less than for urban park walking scenes (UPWSs). Additionally, the visual perception scores of the former (i.e., fascinating, coherent, complex, and mysterious) were higher than the latter. In terms of the visual attention area, the visual exploration of HGWSs around the scene (i.e., top, bottom, left, and right) was longer than for UPWSs, while the latter’s central fixation time was longer than that of the former. The visual attraction of HGWSs was related to the foreground and middle ground, while that of UPWSs was related to the middle ground and background. Additionally, for policy makers and managers of urban green spaces, the recommendation of the present study was to consider and evaluate the differences between HGWSs and UPWSs in terms of visual attraction before policy establishment.

Effects of negative emotional valence on readers’ text processing and memory for text: an eye-tracking study

AbstractComprehension of stories requires readers to take the perspective of the story characters and imagine or feel their cognitive and affective states. The study investigated how variations in emotional valence within a literary text affected readers’ global text processing, as reflected in their eye movements during the first and second-pass reading, and their memory for text. Processes of reading were also examined in relation to readers’ dispositional empathy. Undergraduate students (N = 42) were assigned to an emotionally negative or neutral reading condition. They read a natural text passage from a suspense story while their ocular behavior was registered. After reading, they responded to multiple-choice questions assessing their memory of the text. Results revealed longer first-pass fixation times for content evoking negative emotions than for neutral content, which could be suggestive of a more analytical processing of the former. These effects were however local and did not impact the processing of the text at global level. Memory for the emotionally negative content was more accurate than memory for the neutral content. Dispositional empathy did not contribute to reading processes and outcome. Findings are discussed against the mixed results in the current literature and practical implications are also outlined.

Can Laser-Assisted Indocyanine Green Angiography Be Used to Quantify Perfusion Changes During Staged Fixation of Pilon Fractures? A Pilot Study.

To quantify soft tissue perfusion changes in pilon fractures during staged treatment using laser-assisted indocyanine green angiography (LA-ICGA). Level 1 trauma center. Prospective cohort study. Twelve patients with 12 pilon fractures participated in the study. Seven patients had OTA/AO classification of 43-C3, 3 had 43-C2, and 2 had 43-B2. LA-ICGA was performed with the SPY fluorescence imaging platform. Analysis via ImageJ was used to generate a fractional area of perfusion (FAP) based on fluorescent intensity to objectively quantify soft tissue perfusion. Anterior, medial, and lateral measurements were performed at the time of initial external fixation (EF) application and then at the time of definitive fixation. FAP within the region of interest was on average 64% medially, 61% laterally, and 62% anteriorly immediately before EF placement. Immediately before definitive open reduction internal fixation, fractional region of interest perfusion was on average 86% medially, 87% laterally, and 86% anteriorly. FAP increased on average 24% medially ( P = 0.0004), 26% laterally ( P = 0.001), and 19% anteriorly ( P = 0.002) from the time of initial EF to the time of definitive open reduction and internal fixation. Quantitative improvement in soft tissue perfusion was identified through the course of staged surgical management in pilon fractures. LA-ICGA potentially may be used to determine appropriate timing for definitive surgical intervention based on the readiness of the soft tissue envelope. Ultimately, these findings may influence clinical outcomes with respect to choice of surgical approach, soft tissue management, surgical timing, and wound healing. Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Bone Transport to Arthrodesis for Ankle and Hindfoot Osseous Defects

Category: Trauma; Ankle; Hindfoot Introduction/Purpose: Distal tibia and hindfoot bone defects represent a challenging scenario for the foot and ankle surgeon. Recovering bone stock whilst achieving fusion in an infection-free environment with no soft tissue defects are the main objectives to obtain limb salvage. Bone transport to arthrodesis using distraction osteogenesis is a two-staged procedure for the management of intercalary defects. The initial stage consists of resection of non-vital osseous tissue and installation of a cement spacer. The second stage is performed after the infection process and soft tissue cover is completed and consists of a proximal tibial corticotomy with the installation of a circular external fixation. There are few reports in the literature of the salvage rate, functional/quality of life outcomes and satisfaction results of this technique. Methods: Retrospective IRB-approved study including patients with distal tibial and hindfoot bone defect treated in a trauma level I center between January 2015 and February 2020. We included patients treated with bone transport to tibiotalar o tibiocalcaneal arthrodesis using a circular external fixator with a minimum 12 months follow-up after frame removal. Demographic and clinical data were obtained. In addition, union rates, external fixator times and complications were noted. SMFA and SF-12 scores were obtained for assessing functional results and quality of life respectively. Residual pain was evaluated using a visual analog scale and patient's satisfaction was assessed with a likert-type categorical scale. Results: Eighteen patients with a mean age of 50.9 years (R:24-72) were included in this study. The mean defect size was 7.3 cm (R:3-12) with osteomyielitis of the distal tibia secondary to trauma as the most common etiology. Fifteen cases were transported to tibiotalar artrhodesis and in three cases to tibiocalcaneal artrhodesis. Free flaps were used to cover soft tissue defects in 10 patients (56%). Union rate was 94% (17/18 patients) with one patient requiring a below knee amputation for persistant infection during bone transport. The mean fixator time was 12 months (R:5-20). Conversion to internal fixation was performed in 12 patients. The mean SMFA dysfunction score was 37.9 and bother score 45.3. SF-12 results were 30.5 in the physical score and 45.5 regarding mental health. The mean VAS was 4 and sixteen patients were completely satisfied or satisfied with minor remarks with the procedure (89%). Conclusion: Bone transport to arthrodesis obtained a high rate of limb salvage in this series as a treatment for segmental osseous deficits of the hindfoot and ankle. Nevertheless is a technique that requires a long recovery and external fixation time. Patients at one-year follow-up after frame removal have lower functionality and quality of life scores than the general population but with a high rate of satisfaction.

Arthroscopic Reduction and Internal Fixation of Talus Fractures: An All-Inside Soft-Tissue Preserving Technique

Category: Arthroscopy; Hindfoot; Trauma Introduction/Purpose: Talus fractures, although rare, can lead to devastating complications of posttraumatic osteoarthritis (PTA), mal-union, non-unions, and avascular necrosis (AVN). The timing and method of fixation has been controversial, especially for open and extruded fractures. The purpose of this study is to present short-term outcomes using a posterior talus arthroscopic reduction internal fixation (TARIF) technique. The authors hypothesized that talus fractures reduced arthroscopically and fixed percutaneously would have similar outcomes with reduced overall complications compared to traditional open techniques. Methods: We performed a retrospective study on 14 consecutive patients undergoing primary posterior arthroscopic reduction internal fixation for talus fractures from August 2020 to January 2021. All cases were performed completely arthroscopically, utilizing a posterior approach and cannulated screws. Patient demographics, fracture pattern, perioperative complications, and radiographic findings were collected. Results: The mean age of our cohort was 37.3 years (range, 19-75), including 8 males and 6 females, with 58% utilizing nicotine. Motor vehicle accidents accounted for 64% of injuries, followed by falls and gunshot wounds. Fracture location included 9 body fractures, 5 neck fractures Hawkins type 2 (1), 3 (3), and 4 (1). Five fractures were open injuries, 2 of which had vascular injuries that underwent irrigation and debridement followed by external fixation. Intraoperatively, all patients had 2-3 anterior to posterior 3.5mm cannulated headless screws placed with a mean tourniquet time of 87 minutes (range, 0 - 88). Postoperatively, all fractures had the articular surface restored to within 2mm on radiographs. No patients required antibiotics and no debridement's were performed. No acute AVN has been recorded. Conclusion: Our short-term results indicate posterior arthroscopic reduction internal fixation of talus fractures is safe and able to restore the articular surfaces. It also suggests that an all-inside soft tissue preserving technique may reduce short term complications.

Latent Growth Modeling of Item Process Data Derived From Eye-tracking Technology: An Experimental Study Investigating Reading Behavior of Examinees When Answering A Multiple-Choice Test Item

This study illustrates how eye-tracking data can be translated to “item process data” for multiple-choice test items to study the relationship between subjects’ item responses and choice reading behavior. Several modes of analysis were used to test the hypothesized added value of using process data to identify choice reading patterns of subjects. In addition to the cross-sectional analises of agggregate measurements derived from the time series eye tracking data, Latent Growth Curve Model Analises were undertaken to test if the the shape of change observed in the sequential choice reading patterns differed for subjects depending on their responses to the item being correct or incorrect. Application data were from an experimental study and included seventy-one subjects’ responses to two multiple-choice test items measuring reading comprehension ability in English as a second language. Analyses were carried out for one item at a time. For each item, first, each subject’s recorded eye movements were coded into a set of Area of Interests (AOIs), segmenting the lines in the stem and the individual choices. Next, each subject’s fixation times on the AOIs were time stamped into seconds, indicating when and in what order each subject’s gaze had fixated on each AOI until a choice was marked as the correct answer, which ended the item encounter. A set of nested Latent Growth Curve models were considered for the choice-related AOIs to deliniate if distinct choice-process sequences were evident for correct and incorrect respoders. Model fit indices, random intercepts, slopes, and residuals were computed using the mean log fixation times over item encounter time. The results show that the LGM with the best model fit indicies, for both items, was the quadratic model using response variable as a covariate. Albeit limited due to the two-item – seventy-one subjects experimental setting of the study, the findings are promising and show that utilizing item-level process data can be very useful for defining distinct choice processing (task-oriented reading) patterns of examinees. Over all, the results warrant further study of choice derived AOIs using longitudinal statistical models. It is argued that, the screening methodology desribed in this study can be a useful tool to investigate speededness, distractor functioning, or even to flag subjects with irregular choice processing behavior, such as providing a direct mark on a choice, without any significant reading activity on any of the choices presented (i.e., whether cheating might have occurred.)

초등학교 읽기부진학생들의 읽기능력에 따른 잠재집단별 시선처리 특성 분석

This study analyzes the eye tracking characteristics associated with the reading ability of elementary school students with learning difficulties by using the LPA(latent profile analysis). A total of 32 elementary school students in S city were classified based on the results of the reading test. Eye tracking characteristics of each latent group were compared and analyzed by measuring the movement of the gaze in the reading fluency and silent word reading test. As a result, LPA identified five subgroups with patterns of strengths and weakness in the reading tests. There was a significant difference in the reading test scores for each latent group. Regarding the eye tracking variables for the latent groups, there was a statistically significant difference between the groups in both the total fixation time and regression in the reading fluency test. In addition, it was confirmed that the number of fixed gazes, the number of regressions, and the number of saccades were significant variables in the classification of the latent group. Based on these results, Implications of these results and suggestions for follow-up studies were discussed.

Shortening and re-lengthening versus bone transport for the treatment of distal tibial periarticular post-traumatic defects

In the present study, we presented our experience with a new modified technique of shortening and re-lengthening using a monolateral external frame combined with a calcaneal intramedullary nail and compared it with the bone transport technique for the treatment of distal tibial periarticular post-traumatic defects. Forty-one patients were retrospectively analyzed. Among them 19 were treated using our modified shortening and re-lengthening technique (MSR group) and 22 by bone transport (BT group). The difference in external fixation time (EFT), external fixation index (EFI), self-rating anxiety scale (SAS), and complications were compared between the two groups. The mean EFT was 3.4 ± 0.6 months in the MSR group and 7.5 ± 1.4 months in the BT group; the EFI was 0.57 ± 0.06 month/cm and 1.32 ± 0.23 month/cm, respectively. The EFT, EFI, and SAS scores were significantly lower in the MSR group than in the BT Group (p < 0.05). The mean number of complications per patient in the BT group was nearly 2.4 times that of the MSR group (p < 0.05). Our modified shortening and re-lengthening technique reduced the EFI and complication incidence compared to the bone transport technique. Therefore, patients with distal tibial periarticular post-traumatic defects can achieve great satisfaction with this new technique.

A Study on Visual Perception Differences between Hot Media and Cool Media ——Focusing on Image News and Text News Reading

The study attempted to investigate the visual perception differences between image news and text news using an eye-tracking device, the Tobii, to verify Marshall McLuhan's hot media and cool media theory. Experimental stimuli were four: two news items were edited as image news and text news, respectively. In order to analyze the subjects' visual responses to the actual viewing of the news content, we selected two parameters, Fixation Count and Total of Fixation Duration, from the multiple parameters recorded by the Tobii device. Then we used the AOI tool to divide the stimulus into two regions, the literal part and the whole material, analyzed these two parameters separately. The subjects in this study consisted of 22 people, and they were divided into two groups, each reading one text news item and one image news item. The experimental results showed significant visual perception differences in the Fixation Count between the subjects of the two media. This finding is consistent with McLuhan's hot and cool media theory, suggesting a significant difference between these media on human visual perception. For another parameter of total fixation time, however, although subjects spent more average time on text news relative to image news, this difference was not found to be statistically supported. This section is also discussed in this paper. The present paper discusses McLuhan's concept of hot and cool media and the distinction between the two concepts, the extension of the senses, the sensory ratio, and other important views. Through the vision data collected, this study explores the possibility of using an experimental approach to study McLuhan's theory of hot media and cool media from a sensory perspective. We hope that this research will provide ahelpful addition to understanding the more complex technical and cultural concepts underpinned by hot and cool media.