Cisplatin-based chemotherapy is an established treatment for head and neck squamous cell carcinoma (HNSCC); however, treatment resistance remains a major challenge. Biomarkers predictive of cisplatin response may improve risk stratification and treatment selection. We retrospectively analyzed data from The Cancer Genome Atlas (TCGA)- HNSC dataset to investigate the association between LIM homeobox 1 (LHX1) expression and clinical outcomes, particularly among cisplatin-treated patients. Kaplan–Meier survival analysis and differential expression analyses were conducted based on disease-specific survival (DSS) status. LHX1 mRNA expression in tumor and non-tumor tissues was also assessed using TCGA-derived transcriptomic data. In addition, LHX1 mRNA and protein levels were examined in cisplatin-sensitive oral squamous cell carcinoma (OSCC) cell lines and their matched cisplatin-resistant counterparts. Functional relevance was evaluated by performing siRNA-mediated LHX1 knockdown followed by cisplatin treatment in resistant OSCC cells. LHX1 mRNA expression was significantly higher in HNSCC tumors compared with non-tumor tissues (p < 0.001). High LHX1 expression was associated with poor survival in the overall cohort and in the cisplatin-treated subgroup (log-rank p < 0.05 for both). In the cisplatin-treated subgroup, LHX1 expression was significantly associated with DSS status (p < 0.05, q < 0.05). LHX1 expression was also upregulated in cisplatin-resistant OSCC cells (p < 0.05), and its knockdown enhanced cisplatin sensitivity in resistant OSCC cells (p < 0.05). LHX1 may be associated with adverse outcomes and cisplatin resistance in HNSCC/OSCC, supporting its potential as a treatment-relevant biomarker.

Background: Forward head posture (FHP) has become increasingly common owing to the widespread use of digital devices and sedentary work environments. This postural deviation leads to muscle imbalances, increased cervical and shoulder tension, and reduced range of motion (ROM). Various exercises and Transfer Electrode Capacitive and Resistive (TECAR) therapy are frequently used to address FHP-related problems. However, direct comparisons of their immediate effects remain limited. Objects: This study aimed to compare the immediate effects of TECAR therapy and self-exercise (SE) on cervical ROM, muscle tone, and rounded shoulder posture in patients with FHP. Methods: Thirty adults with FHP were randomly assigned to either the TECAR therapy group (n = 15) or the SE group (n = 15). Each group received one 20-minute session. The TECAR group underwent capacitive- and resistive-mode treatments applied to the cervical and shoulder regions to promote thermal relaxation. The SE group performed supervised stretching of the sternocleidomastoid (SCM), upper trapezius, scalene, and pectoralis major (PM); shoulder shrugs; chin tucks; and isometric neck exercises. Cervical ROM, muscle tone, and acromion-totable distance (ATD) were measured before and after the intervention. Statistical analyses were performed using paired and independent t-tests with α = 0.05. Results: Both interventions significantly improved cervical ROM, muscle tone, and ATD (p < 0.05). The TECAR group showed greater improvements in left lateral flexion ROM (p = 0.015), greater reductions in right SCM (p = 0.012) and left PM tone (p = 0.024), and greater correction of right-sided ATD (p = 0.036) than the SE group. Conclusion: TECAR therapy and SE effectively improved cervical mobility, reduced muscle tone, and corrected postural misalignment in patients with FHP. TECAR therapy demonstrated superior short-term effects in promoting muscle relaxation and alignment, supporting its value as an adjunct to exercise-based rehabilitation.

Background: Firefighter helmets are essential protective gear but add significant weight (average 22 kg for full gear), potentially causing neck muscle fatigue and musculoskeletal disorders. While previous studies have focused on static loads or simple movements, few have analyzed the effect of helmet wear on muscle activity during dynamic, multi-planar movements at different pace. Objects: This study aims to evaluate the effects of wearing a standard Korean firefighter helmet on cervical muscle activity and kinematics during three dynamic head movements (flexion–extension, lateral flexion, and rotation) performed at two different pace. Methods: Twenty-four healthy adults participated in this study. Subjects performed three cervical movements at 45 and 75 rpm guided by a metronome, both with and without a helmet. Kinematics were measured using electromagnetic sensors, and electromyography was recorded from the sternocleidomastoid (SCM), upper trapezius, splenius capitis, and cervical erector spinae (CES). Data were analyzed using repeated measures ANOVA. Results: Helmet wear significantly increased SCM activation during the deceleration phase and CES activation during the acceleration phase (p < 0.05) of neck extension. Higher movement pace (75 bpm) significantly increased peak angular velocity and muscle activation across most tasks compared to the slower pace (45 bpm). However, the interaction between helmet wear and pace was not statistically significant. Conclusion: Wearing a firefighter helmet increases the demand on specific cervical muscles, particularly the SCM and CES, to control head momentum and stability. Movement pace appears to be a more dominant factor in increasing muscle load than helmet weight alone in healthy subjects. These findings contribute to the ergonomic design of future firefighter helmets.

Background: The purpose of this study was to examine whether performing cervical stabilization exercises prior to smartphone use could positively influence postural alignment, pain, and cervical mobility in individuals with forward head posture (FHP). Objectives: To investigate the immediate effects of cervical stabilization exercises performed before smartphone use on craniovertebral angle (CVA), cranial rotation angle (CRA), pain, and cervical range of motion (CROM) in individuals with FHP. Design: A randomized controlled trial. Methods: Participants were randomly assigned into two groups: the control group (Con, n=15), which only vied smartphone videos, and the exercise group (Exp, n=15), which performed cervical stabilization exercises before smartphone viewing. All participants used a smartphone for 20 minutes and pre- and post-measurements included CVA, and CRA, CROM, and VAS for pain. Results: The results demonstrated that participants who performed cervical stabilization exercises showed increased CVA and decreased CRA, suggesting an improvement in forward head alignment following smartphone use. In contrast, the control group exhibited decreased CVA, increased CRA, and elevated neck pain scores after smartphone viewing. Additionally, the control group showed a reduction in right lateral flexion range of motion, whereas no significant CROM changes were observed in the Exp group. Between-group comparisons revealed significant differences in CVA, CRA, and VAS, supporting the immediate protective effects of exercise. Conclusion: These findings suggest that performing cervical stabilization exercises before smartphone use may help mitigate posture deterioration and pain induced by smartphone viewing. This indicates that pre-emptive cervical stabilization exercise could serve as an effective preventive strategy for individuals with FHP.

In this study, a thermal-fluid-structure coupled analysis was performed to improve the thermal performance of a burner for a coal gasification power plant. After combustion analysis, an average temperature of 1,400°C was obtained, closely matching the actual coal gasification system environment. The highest burner tip surface temperature, 887°C, was achieved at the analysis variable, a coal fines inflow velocity of 8m/s. This temperature was mapped to a thermal-structural analysis model, and by increasing the radius of the cooling channel inside the burner to 5 mm, the analysis confirmed a reduction in thermal stress of approximately 20%. In particular, changing the material to HP50-Nb resulted in significantly superior cooling efficiency compared to Inconel 718 without any cooling channel design. The results of this study will be useful for the optimal design of coal gasification facilities as well as for improving the durability of the facilities.

As the widespread adoption of autonomous vehicles is anticipated, a greater diversity of occupant postures is expected. However, current vehicle safety systems are not adequately designed to accommodate these varied postures, particularly relaxed seating positions, in which severe injuries have been reported during frontal collisions. Therefore, it is essential to investigate the biomechanical responses and injury tolerances of occupants in relaxed postures. In this study, the head kinematics and injury responses of the Hybrid-III and THOR anthropomorphic test devices, as well as the THUMS human body model, in a relaxed posture are analyzed using frontal impact sled simulations equipped with the sled system model developed in the previous study. The simulation results are evaluated through comparison with post-mortem human surrogate data. The findings of this study are expected to contribute to the fundamental design of new head restraint systems for human heads in autonomous vehicles.

Background: Rounded Shoulder Posture (RSP) and Forward Head Posture (FHP) often result from prolonged digital device use, leading to muscle imbalance, pain, and functional limits. Growing demand for postural correction highlights the need for effective exercise approaches. Objectives: This study compared strengthening, self-stretching, and mixed exercises on acromion height, craniovertebral angle, and muscle tone in adults with FHP and RSP. Design: Randomized controlled pretest-post test trial over four weeks. Methods: Thirty university students (acromion height ≥2.5 cm, craniovertebral angle ≤53°) were randomly assigned to strengthening (n=6), self-stretching (n=9), or mixed exercise (n=9) groups. Participants exercised three times weekly for four weeks. Pre- and post-tests measured acromion height, craniovertebral angle, and muscle tone of the pectoralis major, upper trapezius, and sternocleidomastoid using MyotonPro®. Data were analyzed with Wilcoxon signed ranks, Kruskal-Wallis, and repeated measures ANOVA (P<.05). Results: All groups significantly improved acromion height and craniovertebral angle (P<.05) without intergroup differences. Significant tone change appeared only in the upper trapezius (P<.05), with the mixed group showing the largest improvement. Conclusion: All exercises improved posture in adults with FHP and RSP. Mixed exercise yielded the greatest reduction in upper trapezius tone, suggesting a multimodal approach may be most effective.

Background: With rapid advances in digital technology, tablet PC use among university students has increased significantly. While convenient, prolonged use often causes neck and shoulder discomfort due to poor posture, such as forward head posture and rounded shoulders. Although students commonly use tablets for writing, there is limited research on head movements during these tasks. Objects: To compare frontal plane head movements and tablet tilt angles between college students with and without neck pain during tablet PC use. Methods: Participants were divided into two groups based on neck pain presence (neck pain group and no pain group). Each participant sat at a table, adjusted the tablet stand angle independently, and placed the tablet accordingly. Participants wore earphones and dictated English sentences to ensure focused handwriting and the evaluator recorded all process. These video recordings of handwriting sessions were analyzed for frontal plane head movements using Kinovea software. The Wilcoxon signed-rank test was applied to reveal the group differences in tablet tilt angle, total head movement (THM), horizontal head movement (HHM), and vertical head movement (VHM). Results: There were no significant differences between the neck pain and no neck pain groups in tablet tilt angle or HHM (p > 0.05). In contrast, the neck pain group exhibited significantly greater THM (p < 0.001) and VHM (p < 0.01). Conclusion: The findings of this study indicate no significant relationship between neck pain and tablet tilt angle or HHM, but a significant association with increased VHM and THM. These findings provide basic knowledge for understanding movement patterns in individuals with neck pain.

Background: The progressive digitalization of contemporary life, coupled with prolonged sedentary behavior, has contributed to the widespread occurrence of forward head posture (FHP) in the general population. Among the various exercise interventions aimed at correcting FHP, stretching exercises and proprioceptive training have garnered significant attention. Objectives: To investigate the effects of stretching exercises and proprioceptive training on craniovertebral angle (CVA), an indicator of forward head posture (FHP), and on the muscle tone of the suboccipital muscles. Design: Randomized controlled trial. Methods: Thirty participants were randomly assigned to either the stretching exercise group (n=15) or the proprioceptive training group (n=15), and each group underwent intervention three times per week for six weeks. CVA and muscle tone of the suboccipital muscles were measured before and after the six-week intervention, and the results were statistically analyzed for comparison. Results: Both groups showed a significant increase in CVA after the intervention (P<.05), with no significant difference between the groups. The muscle tone of the suboccipital muscles did not show statistically significant changes either within or between the groups. Conclusion: Six weeks of stretching exercise and proprioceptive training both resulted in a significant increase in CVA, demonstrating that both interventions are effective in improving FHP. However, neither intervention produced significant changes in the muscle tone of the suboccipital muscles.

본 연구는 뇌 DWI에서 딥러닝 적용 시 48채널과 8채널 헤드 코일 간 영상 품질의 차이를 분석하는 것을 목표로 하였다. 3.0T MRI를 사용하여 두 종류의 코일을 비교하였으며, 딥러닝 알고리즘의 효과를 확인하기 위해 SNR(신호 대 잡음비), ADC(겉보기 확산 계수), SSIM(구조적 유사성 지수)을 측정하였습니다. 연구 결과에 따르면, 딥러닝 적용 후 b-value에 따른 두 코일 간의 차이가 나타났다. 특히 b-value 0 및 1000에서는 딥러닝 적용 전후에 두 코일 간 통계적으로 유의미한 차이가 없었지만, b-value 3000에서는 적용 전후 모두에서 유의미한 차이가 있었다. SSIM 분석에서도 딥러닝 적용 전후 차이는 없었으나, b-value에 따른 차이가 측정되었습니다. 이러한 차이는 영상 판독에 영향을 미칠 수 있으며, 이를 개선하기 위해서는 딥러닝 알고리즘이 부위별, 코일별, 펄스 시퀀스별로 최적화 될 필요가 있다. 따라서 본 연구는 향후 딥러닝 기반 MRI 영상의 정확도와 일관성을 높이기 위한 기초 정보를 제공 하며, 임상적 적용에서 부위별, 수신 코일별, 펄스 시퀀스별로 세분된 딥러닝의 최적화가 필요하다.

This study aimed to develop a systematic process for identifying components that need to be changed to reduce the Head Injury Criterion (HIC) during pedestrian headform tests. Through simulation and analysis, it was confirmed that the hood, hinge, hinge plate, cowl, fender, and fender bracket significantly influence HIC15. The study identified the specific impact of each component on HIC15, allowing for targeted improvements. The proposed process demonstrated superior performance compared to single-component optimization, yielding more significant reductions in HIC15. Multiple vehicle models were tested, confirming the process's effectiveness in consistently lowering HIC15 values.

목적: 가상현실을 구현하는 HMD의 광학계를 이용하여 가상현실 기반의 사위검사법을 개발하였다. 방법: HMD(Oculus rifts, Oculus, USA)를 이용하여 가상현실에 3m 및 40 cm의 사위 시표를 생성했을 때 HMD의 디스플레이에 송출된 타깃의 분리도를 측정하였고, 광학렌즈에 의해 결상된 디스플레이의 타깃 상 위치와 분리도, 배율 등을 산출하였다. 가상현실의 사위 시표는 수정된 토링톤 시표와 마독스 봉을 기반으로 제작했으며, 가상의 검사실을 제작하였고, 사위 측정 방법을 컨트롤러에 프로그래밍하였다. 결과: 가상현실에 3m 및 40 cm의 사위 시표를 생성했을 때 HMD의 디스플레이에 송출된 타깃의 분리도는 각 각 62.49mm, 58.29mm이었다. 디스플레이의 타깃은 광학렌즈에 의해 상 배율 8.07×로 광학렌즈로부터 전방 269.44mm에 상이 맺었으며, 타깃 상의 분리도는 각각 57.51mm, 20.16mm이었다. 사위 시표의 위치 인식은 HMD 사용자의 양안으로부터 양쪽 디스플레이의 타깃 상을 연결한 양안의 주시선이 교차하는 지점에서 이루어지는 것으로 나타났다. HMD를 착용했을 때 양쪽 디스플레이에 검사실 및 사위 시표가 생성되어 양안이 동시 주시를 하 였고, 컨트롤러의 트리거를 당겼을 때 우측 디스플레이의 영상이 적색선으로 교체되면서 양안의 시선이 분리되었 다. 사위검사 시 검사거리의 전환은 컨트롤러의 y-버튼을 이용했으며, 수평 사위 측정은 우측 컨트롤러의 트리거, 수직 사위 측정은 왼쪽 컨트롤러의 트리거를 이용하였다. 결론: 이상으로 가상현실을 기반의 사위검사법을 개발한 본 연구는 안경광학 분야에서 VR 기술의 활용에 대한 기초자료를 제시하였다고 생각한다.

Background: For instance, forward head posture (FHP), characterized by the forward movement of the head relative to the spine, places significant stress on the neck and upper back muscles, disrupting the biomechanical balance of the body. Objects: The objective of this study was to probe the biomechanical effects of FHP on musculoskeletal health through a relative analysis of 26 adults diagnosed with FHP and 26 healthy controls. Methods: In this study, we evaluated the biomechanical impacts of FHP. Participants adjusted their head positions and underwent muscle strength tests, including electromyography assessments and the Biering-Sørensen test for trunk muscle endurance. Data analysis was conducted using Kinovea (Kinovea) and IBM SPSS software ver. 26.0 (IBM Co.) to compare muscle activities between groups with normal and FHPs. Results: The study shows that individuals with FHP have significantly lower muscle activity, endurance, and spinal extension in the erector spinae compared to those without, highlighting the detrimental effects of FHP on these muscles. Conclusion: This study underscores the impact of FHP on erector spinae function and emphasizes the need for posture correction to enhance musculoskeletal health and guide future research on intervention strategies.

Forward Head Posture (FHP) involves the anterior positioning of the head relative to the shoulders, often associated with muscular imbalances. It is known that individuals with FHP experience shortening of craniocervical extensors and cervical flexors. However, contrary to the understanding of flexion in the craniocervical extension subaxial region, a study has reported flexion in the craniovertebral spinal vertebrae among individuals with FHP. The aim of this study was to examine the consistency of biomechanical study results conducted for FHP. The relevant studies were investigated in PubMed and Google Scholar databases using the keywords “forward head posture OR cervical sagittal alignment OR cervical spine AND biomechanics OR kinetic analysis OR kinematic analysis.” During the research selection process, only nine studies relevant to the purpose of our study were identified. Out of these nine studies, four conducted kinematic analysis related to FHP formation, while six conducted kinetic analysis. During the comparison of these studies, five inconsistencies were identified. Biomechanical studies on FHP reveal conflicting findings, suggesting potential variability in the biomechanics of FHP formation across individuals. However, drawing definitive conclusions requires further exploration through additional biomechanical investigations on FHP in the future.

Background: Forward head posture affects many individuals and can cause pain and dysfunction in the muscles and joints of the head, neck, and shoulders. Objectives: This study aimed to assess muscle activity and onset time of cervical and scapular muscles during 180° shoulder flexion and abduction in individuals with normal head posture (NHP) and in those with forward head posture (FHP), both before and after correction. Design: Cross-sectional study. Methods: Thirty-six individuals were divided into FHP and NHP groups. Muscle activity and muscle contraction onset time of the splenius capitis, sternocleidomastoid, upper middle and lower trapezius, and serratus anterior muscles were measured during shoulder flexion and abduction using wireless surface electromyography. Results: The FHP group exhibited increased muscle activity compared to the NHP group (P<.05), notably in the sternocleidomastoid and middle trapezius muscles, more so during shoulder abduction than flexion (P<.05). Regarding muscle contraction onset time, sternocleidomastoid onset was fastest during shoulder abduction in the FHP group (P<.05), while serratus anterior onset was slowest during both shoulder abduction and flexion (P<.05). Conclusion: These findings highlight distinct muscle activity and muscle contraction onset time patterns based on head posture and shoulder movement. Selective muscle activation strategies may help reduce heightened sternocleidomastoid and trapezius activity and enhance serratus anterior engagement in individuals with FHP.