Screen viewing patterns and their association with mental wellbeing and psychological distress: a cross-sectional study amongst university students.

BACKGROUND: Dependency on screen viewing (SV) has reached unprecedented levels, and mental health issues are becoming a major public health concern. However, the associations between SV, including variations in purposes, devices, and timing, and mental health remain unclear. This study aims to provide insights into these associations among university students. METHODS: This analysis used baseline data from a longitudinal cohort study among first-year university students matriculating in the 2021-2022 academic year. Self-reported data on sociodemographics, health behaviors and mental health outcomes alongside anthropometric measurements were collected. Unadjusted and adjusted logistic regression analyses were conducted. RESULTS: The average age of the 997 valid students was 20.2 years, with 59.6% being female and 41.4% male. Students spent 14.3 h daily on SV, with females reporting higher SV than males. Daily SV was predominant for study purposes (7.6 h/day). Computer usage was the highest (7.0 h/day), while TV usage was the lowest (1.7 h/day). Poor mental wellbeing was reported by 33.6% of students, while 13.9% experienced psychological distress. Compared to students with low total SV, those with high levels were more likely to have poor mental wellbeing [OR (95% CI): 1.40 (0.99, 1.98)] and psychological distress [1.56 (1.00, 2.44)]. High levels of recreational and study related SV were significantly associated with poor mental wellbeing [1.81 (1.27, 2.56)] and psychological distress [1.75 (1.11, 2.83)], respectively. Those with high levels of computer time were more likely to have poor mental wellbeing [1.44 (1.01, 2.06)], and high weekend day SV was associated with greater odds of psychological distress [2.16 (1.17, 4.06)]. CONCLUSIONS: SV among university students was high, as was the high prevalence of poor mental wellbeing and psychological distress. Greater SV was associated with poor mental wellbeing and psychological distress. Differences according to purpose of SV were noted. Although recreational SV was associated with poor mental wellbeing, study related SV was associated with psychological distress. Variations across different devices and timing were also noted. This highlights the need for further longitudinal research to understand the impact of SV on mental health and to guide interventions for promoting mental health of university students globally.

Ambient intelligence-based monitoring of staff and patient activity in the intensive care unit.

BACKGROUND: Caregiver workload in the ICU setting is difficult to numerically quantify. Ambient Intelligence utilises computer vision-guided neural networks to continuously monitor multiple datapoints in video feeds, has become increasingly efficient at automatically tracking various aspects of human movement. OBJECTIVES: To assess the feasibility of using Ambient Intelligence to track and quantify allpatient and caregiver activity within a bedspace over the course of an ICU admission and also to establish patient specific factors, and environmental factors such as time ofday, that might contribute to an increased workload in ICU workers. METHODS: 5000 images were manually annotated and then used to train You Only LookOnce (YOLOv4), an open-source computer vision algorithm. Comparison of patientmotion and caregiver activity was then performed between these patients. RESULTS: The algorithm was deployed on 14 patients comprising 1762800 framesof new, untrained data. There was a strong correlation between the number ofcaregivers in the room and the standardized movement of the patient (p < 0.0001) withmore caregivers associated with more movement. There was a significant difference incaregiver activity throughout the day (p < 0.05), HDU vs. ICU status (p < 0.05), delirious vs. non delirious patients (p < 0.05), and intubated vs. not intubated patients(p < 0.05). Caregiver activity was lowest between 0400 and 0800 (average .71 ± .026caregivers per hour) with statistically significant differences in activity compared to 0800-2400 (p < 0.05). Caregiver activity was highest between 1200 and 1600 (1.02 ± .031 caregivers per hour) with a statistically significant difference in activity comparedto activity from 1600 to 0800 (p < 0.05). The three most dominant predictors of workeractivity were patient motion (Standardized Dominance 78.6%), Mechanical Ventilation(Standardized Dominance 7.9%) and Delirium (Standardized Dominance 6.2%). CONCLUSION: Ambient Intelligence could potentially be used to derive a single standardized metricthat could be applied to patients to illustrate their overall workload. This could be usedto predict workflow demands for better staff deployment, monitoring of caregiver workload, and potentially as a tool to predict burnout.

Comparison of cutaneous facial temperature using infrared thermography to standard temperature measurement in the critical care setting.

To assess the accuracy and precision of infrared cameras compared to traditional measures of temperature measurement in a temperature, humidity, and distance controlled intensive care unit (ICU) population. This was a prospective, observational methods comparison study in a single centre ICU in Metropolitan Melbourne, Australia. A convenience sample of 39 patients admitted to a single room equipped with two ceiling mounted thermal imaging cameras was assessed, comparing measured cutaneous facial temperature via thermal camera to clinical temperature standards. Uncorrected correlation of camera measurement to clinical standard in all cases was poor, with the maximum reported correlation 0.24 (Wide-angle Lens to Bladder temperature). Using the wide-angle lens, mean differences were - 11.1 °C (LoA - 14.68 to - 7.51), - 11.1 °C ( - 14.3 to - 7.9), and - 11.2 °C ( - 15.23 to - 7.19) for axillary, bladder, and oral comparisons respectively (Fig. 1a). With respect to the narrow-angle lens compared to the axillary, bladder and oral temperatures, mean differences were - 7.6 °C ( - 11.2 to - 4.0), - 7.5 °C ( - 12.1 to - 2.9), and - 7.9 °C ( - 11.6 to - 4.2) respectively. AUCs for the wide-angle lens and narrow-angle lens ranged from 0.53 to 0.70 and 0.59 to 0.79 respectively, with axillary temperature demonstrating the greatest values. Infrared thermography is a poor predictor of patient temperature as measured by existing clinical standards. It has a moderate ability to discriminate fever. It is unclear if this would be sensitive enough for infection screening purposes. Fig. 1 Bland-Altman plots for temperatures measured using clinical standards to infrared camera. a Wide-angle camera versus bladder temperature. b Narrow-angle camera versus bladder temperature.

A Deep Learning-Based Camera Approach for Vital Sign Monitoring Using Thermography Images for ICU Patients.

Infrared thermography for camera-based skin temperature measurement is increasingly used in medical practice, e.g., to detect fevers and infections, such as recently in the COVID-19 pandemic. This contactless method is a promising technology to continuously monitor the vital signs of patients in clinical environments. In this study, we investigated both skin temperature trend measurement and the extraction of respiration-related chest movements to determine the respiratory rate using low-cost hardware in combination with advanced algorithms. In addition, the frequency of medical examinations or visits to the patients was extracted. We implemented a deep learning-based algorithm for real-time vital sign extraction from thermography images. A clinical trial was conducted to record data from patients on an intensive care unit. The YOLOv4-Tiny object detector was applied to extract image regions containing vital signs (head and chest). The infrared frames were manually labeled for evaluation. Validation was performed on a hold-out test dataset of 6 patients and revealed good detector performance (0.75 intersection over union, 0.94 mean average precision). An optical flow algorithm was used to extract the respiratory rate from the chest region. The results show a mean absolute error of 2.69 bpm. We observed a computational performance of 47 fps on an NVIDIA Jetson Xavier NX module for YOLOv4-Tiny, which proves real-time capability on an embedded GPU system. In conclusion, the proposed method can perform real-time vital sign extraction on a low-cost system-on-module and may thus be a useful method for future contactless vital sign measurements.

Inferior Alveolar Nerve Injury in Trauma-Induced Mandible Fractures.

PURPOSE: This prospective observational cohort study sought to determine the prevalence of inferior alveolar nerve (IAN) injury after mandibular fractures before and after treatment and to elucidate factors associated with the incidence of post-treatment IAN injury and time to normalization of sensation. MATERIALS AND METHODS: Consenting patients with mandibular fractures (excluding dentoalveolar, pathologic, previous fractures, or mandibular surgery) were prospectively evaluated for subjective neurosensory disturbance (NSD) and underwent neurosensory testing before treatment and then 1 week, 1.5, 3, 6, and 12 months after treatment. RESULTS: Eighty patients (men, 83.8%; mean age, 30.0 yr; standard deviation, 12.6 yr) with 123 mandibular sides (43 bilateral) were studied. Injury etiology included assault (33.8%), falls (31.3%), motor vehicle accidents (25.0%), and sports injuries (6.3%). Half the fractures (49.6%) involved the IAN-bearing posterior mandible; all condylar fractures (13.0%) had no NSD. Treatment included open reduction and internal fixation (ORIF; 74.8%), closed reduction and fixation (22.0%), or no treatment (3.3%). Overall prevalence of IAN injury was 33.7% (95% confidence interval [CI], 24.8-42.6) before treatment and 53.8% (95% CI, 46.0-61.6) after treatment. In the IAN-bearing mandible, the prevalence was 56.2% (95% CI, 43.2-69.2) before treatment and 72.9% (95% CI, 63.0-82.7) after treatment. In contrast, this prevalence in the non-IAN-bearing mandible was 12.6% (95% CI, 4.1-21.1) before treatment and 31.6% (95% CI, 20.0-43.3) after treatment. Factors associated with the development of post-treatment IAN injury included fracture site and gap distance (a 1-mm increase was associated with a 27% increase in odds of post-treatment sensory alteration). Time to normalization after treatment was associated with type of treatment (ORIF inhibited normalization) and fracture site (IAN-bearing sites took longer to normalize). CONCLUSION: IAN injury was 4 times more likely in IAN-bearing posterior mandibular fractures (56.2%) than in non-IAN-bearing anterior mandibular fractures (12.6%). After treatment, IAN injury prevalence (in 12 months) was higher (72.9% in posterior mandible, 31.6% in anterior mandible).

Gingival Necrosis Related to Sepsis-Induced Agranulocytosis Due to Pseudomonas aeruginosa Bacteraemia: A Case Report.

Background: There have been no reports of sepsis-induced agranulocytosis causing gingival necrosis in otherwise medically healthy patients to the authors' best knowledge. Even though there are several case reports of gingival necrosis secondary to medication-induced agranulocytosis, they have not systematically described the natural progression of agranulocytosis-related gingival necrosis. Methods: This paper presents a case report of a 29-year-old female Indian patient with generalised gingival necrosis and constitutive signs of intermittent fever, nausea, and vomiting. She also complained of abdominal pains. Blood counts showed agranulocytosis, and the patient was admitted for a workup of the underlying cause. Parenteral broad-spectrum antibiotics were administered, which brought about clinical resolution. Results: Her gingival necrosis was attributed to sepsis-induced agranulocytosis triggered by Pseudomonas aeruginosa bacteraemia, and upon clinical recovery, spontaneous exfoliation left behind exposed bone. Secondary healing over the exposed alveolar bone was noted after a year-long follow-up, albeit with some residual gingival recession. Conclusions: Oral manifestations of gingival necrosis, when present with concomitant constitutive symptoms, could indicate a serious underlying systemic condition that could be potentially life-threatening if left untreated. Dentists should be cognizant of this possibility so that timely intervention is not delayed.

An Investigation on the Most Likely Failure Locations in the BEoL Stack of a 20 nm Chip Due to Chip Package Interaction with the Use of Novel Semi-Elliptical Cracks.

The era of 20 nm integrated circuits has arrived. There exist abundant heterogeneous micro/nano structures, with thicknesses ranging from hundreds of nanometers to sub-microns in the IC back end of the line stack, which put stringent demands on the reliability of the device. In this paper, the reliability issues of a 20 nm chip due to chip-package interaction during the reflow process is studied. A representative volume element of the detailed complex BEoL structure has been analyzed to obtain mechanical properties of the BEoL stack by adopting a sub-model analysis. For the first time, semi-elliptical cracks were used in conjunction with J-integral techniques to analyze the failure caused by Chip-to-Package Interaction for a 20 nm chip. The Energy Release Rate(ERR)for cracks at various interfaces and locations in the BEoL stack were calculated to predict the most likely mode and location of failure. We found that the ERR of interfacial cracks at the bottom surface of the interconnects are, on average, more than double those at the sidewalls, which are in turn more than double the number of cracks in the low-k inter-layer dielectric. A total of 500 cycles of thermal shock were conducted, which verified the predictions of the finite element simulations.

Infrared thermography as a modality for tracking cutaneous temperature change and post-mortem interval in the critical care setting.

PURPOSE: To evaluate the potential use of cutaneous facial temperature change as measured by an infrared camera as a marker of postmortem interval (PMI) in the minutes immediately following death. METHODS: This was a prospective, observational pilot study using a convenience sample of all deaths which occurred in a room in an Intensive Care Unit equipped with a ceiling mounted thermal camera. Cutaneous temperature measurements were taken from 60 min antemortem to as long as possible postmortem. RESULTS: A total of 134 separate measurements was taken from 5 patients, with 65 occurring antemortem, and 69 occurring post-mortem. The longest recorded post-mortem time was 130 min. A Kruskal-Wallis ANOVA testing the hypothesis that there was a difference in facial temperature at each of the different timepoints showed significance (p = 0.029). Post-Hoc comparisons were then performed to compare median temperature values at each timeframe to the baseline value. Compared to baseline, there was a significant difference in facial temperature at 30, 60, and 90 min (p = 0.007, p = 0.01, p = 0.016) (Table 2). CONCLUSION: There is a statistically significant cutaneous facial temperature change in patients immediately following death as measured by a thermal camera. There is potential for infrared thermography to identify changes immediately before and after death in environments where traditional temperature measurement cannot be accomplished. More work needs to be done to confirm whether a precise postmortem interval (PMI) could be derived from these values.

Effectiveness of On-Court Resistive Warm-Ups on Change of Direction Speed and Smash Velocity during a Simulated Badminton Match Play in Well-Trained Players.

In badminton, power production can be enhanced through the fundamental practice of a dynamic warm-up with resistance conditioning activity to induce a post-activation performance enhancement (PAPE) effect. The use of heavy resistance exercise in the form of heavy weights to induce PAPE during competition is not logistically practical in the badminton arena. Thus, there is a need to investigate the use of easily available alternative preconditioning stimuli to induce a similar potentiating effect in badminton-specific performance. This study adopted a repeated-measures design of three warm-up conditions: control (CON), weighted wearable resistance (WWR), and resistance band variable resistance (BVR). Fourteen badminton players from the national training squad (11 males, 3 females, age 18 ± 1 y) completed the experimental sessions in random order. Change of direction speed (CODS) and smash velocity (SV) tests were performed at five timepoints-baseline test after the warm-up and at the end of each of the four exercise blocks of a simulated match play protocol. CODS was significantly faster under the two resistance warm-up conditions (WWR and BVR) compared to the CON condition at baseline (-0.2 s ± 0.39 and -0.2 s ± 0.46, p = 0.001 and 0.03, g = 0.47 and 0.40, respectively), but there were no differences at the other timepoints (all p > 0.05). SV was significantly faster for all the four exercise blocks than at baseline under all three warm-up conditions (p = 0.02), but there were no differences in SV between the three warm-up conditions across all the five measured timepoints (p = 0.15). In conclusion, implementing resistance (~10% body weight) in sport-specific plyometric exercises using WWR or BVR during warm-up routines may induce PAPE effects on the change of direction speed but not smash velocity, in well-trained badminton players, as compared with the same warm-up exercises using bodyweight (i.e., CON condition). The positive effects of CODS were, however, observed only at the start of the match and possibly lasted for up to between 5 and 10 min of match play.

Modified technique for frontal sinus obliteration using calvarial bone and Tisseel glue.

BACKGROUND: Frontal sinus obliteration is indicated in trauma and frontal sinus disease. We present our experience with a modified technique of frontal sinus obliteration. METHODS: We reviewed the records of 17 patients who underwent frontal sinus obliteration with a combination of Tisseel fibrin glue (Baxter Healthcare Corporation, Deerfield, IL) and calvarial bone and describe our technique. RESULTS: One female and 16 male patients (mean age, 36.6) underwent frontal sinus obliteration from 2001 to 2005. Traumatic fracture was the most common indication. The patients were followed up for a median of 15 months. There were no major complications. Postoperatively, one patient developed a localized frontal wound infection at 3 weeks; this resolved with debridement. At latest follow-up, all were free from local sinus complications, disease recurrence, headaches, or intracranial events. CONCLUSIONS: The combined use of autogenous calvarial bone and Tisseel is suitable for frontal sinus obliteration. Our technique is associated with low donor site morbidity, avoids a separate donor surgical site, and has a low complication rate.

Nerve Injury After Surgical Excision of Mandibular Third Molars Under Local Anesthesia: An Audit.

BACKGROUND: Injury of the inferior alveolar nerve (IAN) sustained during surgical removal of an impacted lower third molar may cause paresthesia of the lower lip, chin, lower gingivae and anterior teeth. Lingual nerve (LN) injuries may result in ipsilateral paresthesia of the anterior two thirds of the tongue, mucosa of floor of mouth and lingual gingivae. A close anatomic relationship between the roots of the third molar and mandibular canal places the IAN at risk of damage. PURPOSE: The primary aim of this retrospective audit was to ascertain the incidence of IAN and LN damage after mandibular third molar surgery in National Dental Centre Singapore. A secondary aim was to identify the contributory factors for the risk of IAN and LN nerve injury on the basis of the data collected. METHODS: This retrospective audit included 1276 mandibular third molar surgical removals performed in the local anesthesia operating theatre (LAOT) at the National Dental Centre Singapore (NDCS) from April to December 2013. Data included patient details, clinical characteristics, and 1 week postoperative presence/absence of sensory alteration as reported by the patient. RESULTS: Summary of results- Out of 1276 third molar sites audited, 8 (0.62%) sites had altered sensation of the IAN and 1 (0.078%) had altered sensation of the LN at 1 week postoperative review. CONCLUSION: The incidence of IAN injury (0.62%) and lingual Nerve injury (0.08%) after one week from surgery in our audit was low compared to similar studies. This retrospective audit did not show any correlation of nerve injury to age, gender, race, site, angulation of tooth, grade of operator, removal of bone or tooth division. There was no single radiological sign associated with paresthesia, although the most common radiological signs were interruption of the canal line and darkening of the roots.

Keratoprosthesis surgery for end-stage corneal blindness in asian eyes.

PURPOSE: To establish a multidisciplinary surgical program for osteo-odonto-keratoprosthesis (OOKP) surgery in Asia and to evaluate efficacy and preliminary safety of this keratoprosthesis in end-stage corneal and ocular surface disease. DESIGN: Prospective noncomparative case series. PARTICIPANTS: Sixteen adults of Asian ethnic origin, bilaterally blind with end-stage corneal blindness from Stevens-Johnson syndrome, or severe chemical or thermal burns. METHODS: Osteo-odonto-keratoprosthesis surgery involves 2 procedures-in stage 1, an autologous canine tooth is removed, modified to receive an optical polymethyl methacrylate cylinder, and implanted into the cheek. The ocular surface is denuded and replaced with full-thickness buccal mucosa. Stage 2 surgery, performed 2 to 4 months later, involves retrieval of the tooth-cylinder complex and implanting it into the cornea, after reflection of the buccal mucosal flap, corneal trephination, iris and lens removal, and anterior vitrectomy. Concurrent glaucoma and vitreoretinal procedures are also performed at either stage, as required. MAIN OUTCOME MEASURES: Visual acuity (VA), field of vision, anatomical integrity and stability, and ocular and oral complications related or unrelated to the OOKP device. RESULTS: Osteo-odonto-keratoprosthesis surgery was performed on 15 patients, with a mean follow-up of 19.1 months (range, 5-31). Intraoperative complications included expulsive hemorrhage (keratoprosthesis device not implanted), tooth fracture (n = 1), oronasal fistula (n = 1), and mild inferior optic tilt (n = 1). Anatomical stability and keratoprosthesis retention has been maintained in all eyes, with no dislocation, extrusion, retroprosthetic membrane formation, or keratoprosthesis-related infection. Other complications not directly related to device insertion included retinal detachment (RD) related to silicone oil removal (n = 1) and endophthalmitis related to endoscopic cyclophotocoagulation performed 1 year after OOKP surgery (n = 1). Eleven patients (73.3%) attained a stable best spectacle-corrected VA of at least 20/40 or better, whereas 9 (60%) attained stable 20/20 vision. Four patients achieved their best visual potential, ranging from 20/100 to counting fingers vision, related to preexisting glaucomatous optic neuropathy or previous RD. CONCLUSIONS: Establishment of our OOKP program suggests that OOKP surgery has the potential to restore good vision to the most severe cases of corneal blindness in an Asian setting, with minimal device-related complications. Longer follow-up of these cases is currently underway.

Immediate repair of transected inferior alveolar nerves in sagittal split osteotomies.

BACKGROUND: Injury to the inferior alveolar nerve (IAN) in orthognathic surgery is a well-documented complication with the incidence of IAN transection in sagittal split osteotomies (SSOs) ranging from 1.3% to 7.0%. PATIENTS AND METHODS: We describe our clinical experience with 3 cases of immediate microneural repair of IANs transected during SSO. RESULTS: Three cases of IAN transection (2 Sunderland degree V injuries, and 1 degree VI injury) that occurred during SSO were microsurgically repaired immediately by a trained microsurgeon. The other orthognathic surgery sites were positioned and fixed before the nerve repair commenced, and fixation of the nerve injury site was completed by the microsurgeon after nerve repair. All 3 patients were followed for at least 1 year with neurosensory testing, and showed recovery to mild or no sensory impairment. None had functional problems such as drooling, lip-biting, or speech difficulties at 1 year after surgery. CONCLUSION: Immediate nerve repair for transected IANs during SSO may be a feasible option, but requires the availability of a microsurgeon, instrumentation, and operating-room time.

Canine and Premolar Root Dimensions in Chinese. A Reference for Osteoodontokeratoprosthesis Surgery.

PURPOSE: Osteoodontokeratoprosthesis (OOKP) surgery is used to restore vision in end-stage corneal disorders, where an autogenous tooth supporting an optical cylinder is implanted through the cornea under a buccal mucosal graft. The ideal tooth for OOKP is a healthy single-rooted permanent tooth with sufficient buccolingual/palatal root diameter to accommodate an optical cylinder. The aim of this study was to determine the buccolingual/palatal diameters of canine and premolar roots in Chinese, for selection of teeth for OOKP surgery. DESIGN: This was an anatomical study on root dimensions of extracted intact teeth. METHODS: Extracted canine and premolar teeth (excluding maxillary first premolars) were collected and the buccolingual/palatal and mesiodistal diameters of the root at the cervical line and at 2-mm intervals below the cervical line were measured with Vernier calipers. Other measurements included total tooth length, crown buccolingual/palatal diameter, and root length. Mean and minimum buccolingual/palatal root diameters were compiled for each 2-mm interval. RESULTS: A total of 415 extracted teeth (198 male, 217 female) were collected and measured. Recorded dimensions of keratoprostheses in 55 previous OOKP surgeries were used to establish acceptable lamina dimensions to ascertain root size adequacy. Premolars in Chinese female patients were undersized in a small minority. Minimal dimensions of teeth were insufficient if at 6 mm root level, the buccolingual/palatal width was less than 5 mm, or the mesiodistal width was less than 3 mm. This was noted in female mandibular first premolars (5.6%), maxillary second premolars (4.5%), and mandibular second premolars (1.5%). CONCLUSIONS: Canines have adequate dimensions for OOKP surgery. However, premolars in Chinese females may be undersized in a small minority.

Cell yield, proliferation, and postexpansion differentiation capacity of human ear, nasal, and rib chondrocytes.

Human ear, nasal, and rib chondrocytes were compared with respect to their suitability to generate autologous cartilage grafts for nonarticular reconstructive surgery. Cells were expanded for two passages in medium containing 10% fetal bovine serum without (control) or with transforming growth factor beta(1) (TGF-beta(1)), fibroblast growth factor 2 (FGF-2), and platelet-derived growth factor bb (PDGF-bb) (TFP). Expanded cells were cultured as three-dimensional pellets in chondrogenic serum-free medium containing insulin, dexamethasone, and TGF-beta(1). Chondrocytes from all three sources were successfully isolated, increased their proliferation rate in response to TFP, and dedifferentiated during passaging. Redifferentiation by ear and nasal, but not rib, chondrocytes was enhanced after TFP expansion, as assessed by the significant increase in glycosaminoglycan (GAG)/DNA content and collagen type II mRNA expression in the resulting pellets. TFP-expanded ear and nasal chondrocytes generated pellets of better quality than rib chondrocytes, as assessed by the significantly higher GAG/DNA content and collagen type II mRNA expression, and by the relative stain intensities for GAG and collagen types I and II. In conclusion, postexpansion cell yields suggest that all three sources investigated could be used to generate autologous grafts of clinically relevant size. However, ear and nasal chondrocytes, if expanded with TFP, display superior postexpansion chondrogenic potential and may be a preferred cell source for cartilage tissue engineering.

Interface of unloaded titanium implants in the iliac crest, fibula, and scapula: a histomorphometric and biomechanical study in the pig.

PURPOSE: Prefabrication of free vascularized fibular flaps is a 2-stage procedure for the reconstruction of maxillary and mandibular defects. The delay between prefabrication and flap transfer is 6 weeks and depends on biomechanical stability and osseointegration of the implants. The purpose of this animal study was to evaluate implant stability by measuring the removal torque values (RTVs) at 3, 6, and 12 weeks and to compare the results with interface strength of the bone-implant surface in the fibula, the scapula, and the iliac crest under unloaded conditions. MATERIALS AND METHODS: ITI implants (n = 108) with a sandblasted and acid-etched surface were placed in the fibula, the scapula, and the iliac crest of 6 Yorkshire pigs. Biomechanical, histologic, and histomorphometric results were collected at 3, 6, and 12 weeks, respectively. RESULTS: Bicortical anchored 8-mm implants in the fibula (63.7 to 101.8 Ncm) showed RTVs similar to those of monocortical anchored 12-mm implants in the scapula (62.3 to 99.7 Ncm). The RTVs of monocortical anchored 8-mm and 10-mm implants in the iliac crest (19.1 to 44.3 Ncm) and the scapula (27.2 to 55.3 Ncm) were significantly lower. The bone-to-implant contact in the fibula at 3, 6, and 12 weeks (35.2%, 44.4%, and 46.8%, respectively) was similar to that in the iliac crest (24.2%, 44.2%, and 52.5%, respectively), but significantly lower than in the scapula (63.7%, 73.8%, and 74.2%, respectively). DISCUSSION AND CONCLUSION: Bicortical anchorage determined implant stability in the fibula, whereas interfacial strength seemed to define stability in the scapula. The quality and type of bone determined the bone's response in terms of biomechanical press fit or biologic interface strength.

The sphenozygomatic suture as a key site for osteosynthesis of the orbitozygomatic complex in panfacial fractures: a biomechanical study in human cadavers based on clinical practice.

The aims of this study were to determine the forces required for fracturing the intact orbitozygomatic complex and to evaluate the strength of the orbitozygomatic complex-fixation, especially with regard to the sphenozygomatic suture as a fixation point. In severe midfacial and panfacial fractures, the sphenozygomatic suture is routinely used in the authors' practice as a key site for fixation of the orbitozygomatic complex, thus establishing a stable outer frame as a basis for subsequent reconstruction. However, this has never been formally described, nor has it been biomechanically tested. Eight human cadaver heads were subjected to forces applied in a standard fashion to the orbitozygomatic complex on both sides (n = 16) using a servohydraulic testing machine. The force required to break the intact orbitozygomatic complex was measured on both sides. Subsequently, fracture patterns were noted and each orbitozygomatic complex (n = 16) was assigned to one of four groups: four-point fixation (zygomatic arch, frontozygomatic suture, infraorbital rim, zygomaticomaxillary buttress) using a 1.3/2.0-mm titanium system (group 1) and a 2.0-mm bioresorbable system (group 3); or three-point fixation (zygomatic arch, frontozygomatic suture, sphenozygomatic suture) using 1.3/2.0-mm titanium system (group 2) and a 2.0-mm bioresorbable system (group 4). Forces for failure of the constructs were measured. The force for failure of the intact orbitozygomatic complex was 1826 +/- 852 N. The mean force required for failure of the reconstructed orbitozygomatic complex was 504 +/- 178 N for group 1, 620 +/- 304 N for group 2, 93 +/- 22 N for group 3, and 133 +/- 31 N for group 4. The titanium constructs provided 27.7 percent (four-point fixation) and 31.7 percent (three-point fixation) of the intact breaking strength of the orbitozygomatic complex, which was significantly higher (p < 0.05) compared with 5.4 percent (four-point fixation) and 7.7 percent (four-point fixation) for the bioresorbable system. Plate bending (91 percent) was the primary cause for failure in the titanium plating system, whereas plate and screw breakage (57 percent) was responsible for failure of the resorbable system. The fixation of the sphenozygomatic suture was a key site in the fixation of the orbitozygomatic complex, which could be demonstrated with superior results in the three-point fixation group compared with the four-point fixation group. The bioresorbable system showed the lowest values in this cadaver study. Further experimental and clinical studies might determine whether the bioresorbable materials are sufficient for the treatment of complex fractures of the orbitozygomatic complex.

Versatile pattern generation of periodic, high aspect ratio Si nanostructure arrays with sub-50-nm resolution on a wafer scale.

We report on a method of fabricating variable patterns of periodic, high aspect ratio silicon nanostructures with sub-50-nm resolution on a wafer scale. The approach marries step-and-repeat nanoimprint lithography (NIL) and metal-catalyzed electroless etching (MCEE), enabling near perfectly ordered Si nanostructure arrays of user-defined patterns to be controllably and rapidly generated on a wafer scale. Periodic features possessing circular, hexagonal, and rectangular cross-sections with lateral dimensions down to sub-50 nm, in hexagonal or square array configurations and high array packing densities up to 5.13 × 107 structures/mm2 not achievable by conventional UV photolithography are fabricated using this top-down approach. By suitably tuning the duration of catalytic etching, variable aspect ratio Si nanostructures can be formed. As the etched Si pattern depends largely on the NIL mould which is patterned by electron beam lithography (EBL), the technique can be used to form patterns not possible with self-assembly methods, nanosphere, and interference lithography for replication on a wafer scale. Good chemical resistance of the nanoimprinted mask and adhesion to the Si substrate facilitate good pattern transfer and preserve the smooth top surface morphology of the Si nanostructures as shown in TEM. This approach is suitable for generating Si nanostructures of controlled dimensions and patterns, with high aspect ratio on a wafer level suitable for semiconductor device production.

Targets of genome copy number reduction in primary breast cancers identified by integrative genomics.

The identification of specific oncogenes and tumor suppressor genes in regions of recurrent aneuploidy is a major challenge of molecular cancer research. Using both oligonucleotide single-nucleotide polymorphism and mRNA expression arrays, we integrated genomic and transcriptional information to identify and prioritize candidate cancer genes in regions of increased and decreased chromosomal copy number in a cohort of primary breast cancers. Confirming the validity of this approach, several regions of previously-known copy number (CN) alterations in breast cancer could be successfully reidentified. Focusing on regions of decreased CN, we defined a prioritized list of eighteen candidate genes, which included ARPIN, FBN1, and LZTS1, previously shown to be associated with cancers in breast or other tissue types, and novel genes such as P29, MORF4L1, and TBC1D5. One such gene, the RUNX3 transcription factor, was selected for further study. We show that RUNX3 is present at reduced CNs in proportion to the rest of the tumor genome and that RUNX3 CN reductions can also be observed in a breast cancer series from a different center. Using tissue microarrays, we demonstrate in an independent cohort of over 120 breast tissues that RUNX3 protein is expressed in normal breast epithelium but not fat and stromal tissue, and widely down-regulated in the majority of breast cancers (>85%). In vitro, RUNX3 overexpression suppressed the invasive potential of MDA-MB-231 breast cancer cells in a matrigel assay. Our results demonstrate the utility of integrative genomic approaches to identify novel potential cancer-related genes in primary tumors. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat.