In-situtemperature-dependent sheet resistance study of Cu films in oxygen ambient for heterogeneous integrations.

Controlling and preventing Cu oxidation is crucial for improving the performance and reliability of Cu-Cu bonding. Ni-B films were selectively deposited on Cu films to block the Cu oxidation. The resistivity changes of the Cu films in N2and O2ambient were measured by using a four-point probe in thein situtemperature-dependent resistance measurements at the temperature from room temperature to 400 °C. The resistivity changes of the 100 nm thick Cu films without Ni-B increased rapidly at a higher temperature (284 °C) in the O2ambiance. The change of resistivity-increase of 100 nm thick Cu with ∼50 nm thick Ni-B (top) film was lower than the Cu films without Ni-B films due to the blocking diffusion of O2atoms by the Ni-B films. The resistivity-change and oxidation barrier properties were studied using scanning electron microscopy, FIB, transmission electron microscopy, EDX, and secondary ion mass spectroscopy tools. The proposed article will be helpful for the upcoming advancement in Cu-Cu bonding using selected-area deposition.

Regulation of the Gut Microbiota and Inflammation by ß-Caryophyllene Extracted from Cloves in a Dextran Sulfate Sodium-Induced Colitis Mouse Model.

Ulcerative colitis is an inflammatory bowel disease characterized by symptoms such as abdominal pain, diarrhea, bleeding, and weight loss. Ulcerative colitis is typically treated with anti-inflammatory drugs; however, these drugs are associated with various side effects, limiting their use. ß-Caryophyllene (BCP), a natural compound derived from cloves, has antioxidant, antibacterial, and anti-inflammatory activities. In this study, we aimed to investigate the effects of BCP on colitis in a dextran sulfate sodium (DSS)-induced colitis mouse model. BCP was administered for seven days, followed by 2.5% DSS for additional seven days to induce colitis. Changes in stool weight, recovery of gut motility, colon length, colon histology, myeloperoxidase activity, inflammatory cytokines (TNF-α, IL-1ß, IL-6, IgA, and IgG), and the gut microbiota were observed. Administration of BCP increased stool weight, restored gut motility, and considerably increased colon length compared to those in the untreated colitis mouse model. In addition, the amount of mucin and myeloperoxidase activity in the colon increased, whereas the concentrations of IL-1ß, IL-6, and TNF-α decreased following the administration of BCP. Furthermore, BCP reduced the abundance of Proteobacteria which can cause intestinal immune imbalance. These results suggest that BCP has a potential to be developed as a preventive agent for colitis.

Spontaneous Spine Fracture in Patient with Ankylosing Spondylitis under Spinal Anesthesia: A Case Report and Review of the Literature.

Factures in ankylosing spondylitis (AS) patients tend to occur due to the absence of motion between vertebrae, poor bone quality, and a long lever arm that generates extension force. However, most patients have a history of at least minor trauma. The aim of this report was that a vertebral fracture in a patient with AS can be caused not only by minor trauma, but also by position changes or maintenance of position for examination due to structural weakness. A 75-year-old woman with AS visited her local hospital on foot for back pain. She usually had back pain. However, she had increased back pain after falling over three weeks prior. In plain radiographs, no fracture was apparent. The doctor tried to perform magnetic resonance imaging (MRI) for further evaluation. However, several attempts of MRI failed due to continuous movement arising from pain. As a result, MRI was performed under spinal anesthesia for pain control. However, complete paraplegia developed during the MRI examination. MRI showed extension-type vertebral fracture with displacement and the patient was transferred to our hospital. We performed emergency posterior fusion, but neurological symptoms did not improve. This case suggests the need for careful positioning, sedation, or anesthesia when performing an examination or surgery in AS patients. We recommend that all patients with AS should be carefully positioned at all times during testing or surgery.

Inhibitory Effects of ß-Caryophyllene on Helicobacter pylori Infection In Vitro and In Vivo.

The human specific bacterial pathogen Helicobacter pylori (H. pylori) is associated with severe gastric diseases, including gastric cancer. Recently, the increasing resistance makes the usage of antibiotics less effectively. Therefore, development of a new antimicrobial agent is required to control H. pylori infection. In the current study, the inhibitory effect of ß-caryophyllene on H. pylori growth, as well as the antibacterial therapeutic effect, has been demonstrated. ß-caryophyllene inhibited H. pylori growth via the downregulation of dnaE, dnaN, holB, and gyrA and also downregulated virulence factors such as CagA, VacA, and SecA proteins. ß-caryophyllene inhibited expression of several T4SS components, so that CagA translocation into H. pylori-infected AGS gastric cancer cells was decreased by ß-caryophyllene treatment. ß-caryophyllene also inhibited VacA entry through the downregulation of T5aSS. After ß-caryophyllene administration on Mongolian gerbils, the immunohistochemistry (IHC) and Hematoxylin&Eosin stains showed therapeutic effects in the treated groups. Hematological data, which was consistent with histological data, support the therapeutic effect of ß-caryophyllene administration. Such a positive effect of ß-caryophyllene on H. pylori infection potently substantiates the natural compound as being capable of being used as a new antimicrobial agent or functional health food to help patients who are suffering from gastroduodenal diseases due to H. pylori infection.

Revision total hip arthroplasty with metal on metal bearing for ceramic bearing fractures.

BACKGROUND: Due to concern of potential metallosis caused by residual microscopic ceramic particles, metal-on-metal (MoM) bearing is deemed undesirable in revision total hip arthroplasty (THA) for ceramic bearing fracture. We determined whether MoM bearing is suitable to be used in revision THA for ceramic fractures and also evaluated whether this treatment increases serum iron levels compared with MoM bearing revision THA for polyethylene failure. METHODS: Between 2006 and 2012, 22 patients underwent revision surgery using MoM bearing (28 mm femoral head in 18 hips and 32 mm in 4 hips) for ceramic bearing fracture and followed average 52.1 months. We assessed radiological parameter and functional outcome using Harris hip score (HHS) and WOMAC score. Also, serum cobalt (Co) and chromium (Cr) blood tests were performed and compared with the result obtained from age, sex- and follow-up duration-matched patients with MoM revision THA for failed polyethylene bearing. RESULTS: The mean HHS improved from 60.6 preoperatively to 90.3 at final follow-up. There were no changes in cup position, progression of osteolytic lesions, and measurable wear of MoM bearing articulation at final follow-up radiographs. There was one case of recurrent dislocation after surgery, which was treated with greater trochanter distal advancement and one case of deep infection, which underwent two-stage revision. Mean serum Co level (1.7 vs. 1.4 µg/dl; p = 0.211) and Cr level (0.70 vs. 1.01 µg/dl; p = 0.327) showed no significant difference. CONCLUSIONS: MoM articulation with liner cementation into the acetabular cup along with total synovectomy can be chosen in revision surgery for ceramic fracture with good midterm follow-up. However, the use of MoM bearing is indicated when the stem and metal shell can be retained and ceramic on ceramic or ceramic on polyethylene bearing cannot be selected. Also long-term outcome needs to be further evaluated.

Remote Control of Heterodimeric Magnetic Nanoswitch Regulates the Adhesion and Differentiation of Stem Cells.

Remote, noninvasive, and reversible control over the nanoscale presentation of bioactive ligands, such as Arg-Gly-Asp (RGD) peptide, is highly desirable for temporally regulating cellular functions in vivo. Herein, we present a novel strategy for physically uncaging RGD using a magnetic field that allows safe and deep tissue penetration. We developed a heterodimeric nanoswitch consisting of a magnetic nanocage (MNC) coupled to an underlying RGD-coated gold nanoparticle (AuNP) via a long flexible linker. Magnetically controlled movement of MNC relative to AuNP allowed reversible uncaging and caging of RGD that modulate physical accessibility of RGD for integrin binding, thereby regulating stem cell adhesion, both in vitro and in vivo. Reversible RGD uncaging by the magnetic nanoswitch allowed temporal regulation of stem cell adhesion, differentiation, and mechanosensing. This physical and reversible RGD uncaging utilizing heterodimeric magnetic nanoswitch is unprecedented and holds promise in the remote control of cellular behaviors in vivo.

Autostereoscopic 3D display system with dynamic fusion of the viewing zone under eye tracking: principles, setup, and evaluation [Invited].

We study optical technologies for viewer-tracked autostereoscopic 3D display (VTA3D), which provides improved 3D image quality and extended viewing range. In particular, we utilize a technique-the so-called dynamic fusion of viewing zone (DFVZ)-for each 3D optical line to realize image quality equivalent to that achievable at optimal viewing distance, even when a viewer is moving in a depth direction. In addition, we examine quantitative properties of viewing zones provided by the VTA3D system that adopted DFVZ, revealing that the optimal viewing zone can be formed at viewer position. Last, we show that the comfort zone is extended due to DFVZ. This is demonstrated by a viewer's subjective evaluation of the 3D display system that employs both multiview autostereoscopic 3D display and DFVZ.

Total knee arthroplasty using ultra-congruent inserts can provide similar stability and function compared with cruciate-retaining total knee arthroplasty.

PURPOSE: Recently, ultra-congruent (UC) inserts have shown successful outcomes following total knee arthroplasty (TKA). It was hypothesized that patients in the UC group would not show significantly different in vivo stability or functional outcomes from those in the cruciate-retaining (CR) group. METHODS: The prospective study enrolled patients who had been treated with either CR or UC TKAs (38 cases in each group), after a minimum 3-year follow-up. The same surgical technique was used with the same femoral components in both groups except for the polyethylene inserts (CR or UC). The clinical outcome measures were knee range of motion (ROM), Hospital for Special Surgery (HSS) score, Knee Society (KS) score, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) subscale score. The mediolateral laxity at full extension and anteroposterior laxity at 90° flexion were measured in stress radiographs and compared between the two groups. RESULTS: Both the CR and UC groups showed significant improvements in post-operative ROM, HSS, KS, and WOMAC scores without inter-group differences between two groups. Moreover, there were no differences in mediolateral or anteroposterior laxity between the two groups (p > 0.05). CONCLUSION: TKA with posterior cruciate ligament (PCL) resection using the UC design showed comparable functional outcomes with those of CR TKA and provided similar in vivo stability. Therefore, UC inserts can be a good option in TKA without bony box cut when the PCL is damaged during an operation. LEVEL OF EVIDENCE: II.

Comparison of clinical outcomes and second-look arthroscopic findings after ACL reconstruction using a hamstring autograft or a tibialis allograft.

PURPOSE: The purpose of this prospective randomized clinical study was to compare the clinical and radiological outcomes, including tibial tunnel widening and the progression of osteoarthritis after ACL reconstruction using a hamstring autograft or a tibialis allograft. In addition, we compared the graft tear and synovial coverage of grafts in patients that underwent the second-look arthroscopy. METHODS: Among 184 patients with an ACL injury who underwent ACL reconstruction, 68 patients of autograft group and 64 patients of tibialis allograft group were included for this study after minimum of 2-year follow-up. The Lachman and pivot-shift tests, Tegner activity score, Lysholm knee score, and IKDC score were compared between the two groups. The quadriceps and hamstring isokinetic strengths using dynamometer were also compared. Degree of OA was determined using the Kellgren-Lawrence grading system on the weight-bearing radiographs. In total, 51 patients (26 patients in autograft group and 25 in the tibialis allograft group) underwent the second-look arthroscopy, in which we compared the apparent tear of graft and synovial coverage of grafts. RESULTS: At the final follow-up, there were no statistical significances in the two groups in Lachman and pivot-shift tests (n.s.). The Tegner activity, Lysholm knee score, and IKDC scores were similar in the two groups. Moreover, no significant differences were observed in the muscle power (n.s.). Some patients showed the progression of OA (five in autograft and four in allograft groups) without intergroup difference (n.s.). Regarding the findings of second-look arthroscopy, although there was no significant difference in graft tear, synovial coverage was better in autograft group than in allograft group. CONCLUSION: Even though hamstring autografts and tibialis allografts provided good functional outcomes without significant differences, the second-look arthroscopy revealed that hamstring autografts produced better synovial coverage than tibialis allograft. LEVEL OF EVIDENCE: I.

How Much Does the Anatomical Tibial Component Improve the Bony Coverage in Total Knee Arthroplasty?

BACKGROUND: Recently, anatomical designs in total knee arthroplasty are introduced to address asymmetry of the resected tibia cutting surface. It is still not well known how much improvement would be achieved in total knee arthroplasty, especially in Asian knees. METHODS: We evaluated the bony coverage of 4 commercially available posterior-stabilized tibial designs (3 symmetrical: NexGen, Attune, and Vega; 1 anatomical: Persona) by measuring uncovered areas over 3 different regions: lateroposterior (LP), medioposterior (MP), and mediolateral (ML) areas. The implant size was chosen based on lateral anteroposterior dimension of the implant that most closely matched the corresponding surface of tibia. The knee with over coverage <1 mm and under coverage <2 mm was regarded as having optimal fit. RESULTS: The optimal fit of anatomical design in LP dimension was achieved in 76% of the cases, which was not significantly different from other symmetrical designs (P > .05). The anatomical tibial implant had a more optimal fit in MP and ML dimensions (48% and 42%, respectively) compared to all symmetric designs (P < .05). All symmetrical tibial designs had significant absolute underhang in MP (62%-78%) and ML (24%-34%) areas without difference. The anatomical tibial design had significant improvement for posteromedial coverage by about 69.8%-74.3% compared with the symmetrical designs. CONCLUSION: Recently introduced anatomical tibial design improves surface coverage at the medioposterior dimension in Asian knees. Moreover, there is small improvement in ML fit compared with the symmetrical designs.

Revision Total Hip Arthroplasty Using an Acetabular Reinforcement Ring With a Hook: A Precise Follow-Up, at Average 11.4 Years, of a Previous Report.

BACKGROUND: This study aims at determining the average long-term result of revision total hip arthroplasty (THA) using the acetabular reinforcement ring with a hook (ARRH) and bone grafting in severe acetabular bony defect. Expected 15-year survival of ARRH in revision THA is included in the study. METHODS: Retrospective review of 48 patients (48 hips) with follow-up duration of average 11.4 years (range, 6.1-21.4 years) was conducted. At each follow-up, Harris hip score was used to assess functional outcome, and radiographic acetabular component osteolysis was measured by DeLee and Charnley classification. Bone defects were assessed preoperatively and intraoperatively using American academy of orthopedic surgeons and Paprosky classification. The common modes of ARRH failures were evaluated. Bone consolidation, presence of heterotopic ossification, and complications such as infection and dislocation were recorded. RESULTS: The bone defects were varied and included cavitary, segmental, and combined defects without any pelvic discontinuity. Mean Harris hip score improved from 52.6 points preoperatively to 82.0 points postoperatively. Nine acetabular revisions and 3 stem revisions (2 concurrent with acetabular revisions and 1 isolated stem revision) were performed. There were 5 infected cases and 1 patient with recurrent dislocation. The 11.4-year survival of revision THA with ARRH was 71% as the end point for acetabular revision surgery for any reason. The expected 15-year survival of revision THA with ARRH was 60%. The most common failure mode of ARRH was superomedial migration followed by lateral migration. CONCLUSION: ARRH combined with bone grafting produces relatively good average long-term clinical results.

Fringe periods of color moirés in contact-type 3-D displays.

A mathematical formula of calculating the fringe periods of the color moirés appearing at the contact-type 3-D displays is derived. It is typical that the color moirés are chirped and the period of the line pattern in viewing zone forming optics is more than two times of that of the pixel pattern in the display panel. These make impossible to calculate the fringe periods of the color moirés with the conventional beat frequency formula. The derived formula work very well for any combination of two line patterns having either a same line period or different line periods. This is experimentally proved. Furthermore, it is also shown that the fringe period can be expressed in terms of the viewing distance and focal length of the viewing zone forming optics.

Maximum and minimum amplitudes of the moiré patterns in one- and two-dimensional binary gratings in relation to the opening ratio.

The amplitude of the moiré patterns is estimated in relation to the opening ratio in line gratings and square grids. The theory is developed; the experimental measurements are performed. The minimum and the maximum of the amplitude are found. There is a good agreement between the theoretical and experimental data. This is additionally confirmed by the visual observation. The results can be applied to the image quality improvement in autostereoscopic 3D displays, to the measurements, and to the moiré displays.

Diffraction effects incorporated design of a parallax barrier for a high-density multi-view autostereoscopic 3D display.

We present optical characteristics of view image provided by a high-density multi-view autostereoscopic 3D display (HD-MVA3D) with a parallax barrier (PB). Diffraction effects that become of great importance in such a display system that uses a PB, are considered in an one-dimensional model of the 3D display, in which the numerical simulation of light from display panel pixels through PB slits to viewing zone is performed. The simulation results are then compared to the corresponding experimental measurements with discussion. We demonstrate that, as a main parameter for view image quality evaluation, the Fresnel number can be used to determine the PB slit aperture for the best performance of the display system. It is revealed that a set of the display parameters, which gives the Fresnel number of ∼ 0.7 offers maximized brightness of the view images while that corresponding to the Fresnel number of 0.4 ∼ 0.5 offers minimized image crosstalk. The compromise between the brightness and crosstalk enables optimization of the relative magnitude of the brightness to the crosstalk and lead to the choice of display parameter set for the HD-MVA3D with a PB, which satisfies the condition where the Fresnel number lies between 0.4 and 0.7.

Confidence limits for patient-specific IMRT dose QA: a multi-institutional study in Korea.

This study aims to investigate tolerance levels for patient-specific IMRT dose QA (DQA) using the confidence limits (CL) determined by a multi-institutional study. Eleven institutions participated in the multi-institutional study in Korea. A total of 155 DQA measurements, consisting of point-dose differences (high- and low-dose regions) and gamma passing rates (composite and per-field) for IMRT patients with brain, head and neck (H&N), abdomen, and prostate cancers were examined. The Shapiro-Wilk test was used to evaluate the normality of data grouped by the treatment sites and the DQA methods. The confidence limit coefficients in cases of the normal distribution, and the two-sided Student's t-distribution were applied to determine the confidence limits for the grouped data. The Spearman's test was applied to assess the sensitivity of DQA results within the limited groups. The differences in CLs between the two confidence coefficients based on the normal and t-distributions were negligible for the point-dose data and the gamma passing rates with 3%/3 mm criteria. However, with 2%/2 mm criteria, the difference in CLs were 1.6% and 2.2% for composite and per-field measurements, respectively. This resulted from the large standard deviation and the more sensitive criteria of 2%/2 mm. There was no noticeable correlation among the different QA methods. Our multi-institutional study suggested that the CL was not a suitable metric for defining the tolerance level when the statistics of the sample group did not follow the normality and had a large standard deviation.

Probability of the moiré effect in barrier and lenticular autostereoscopic 3D displays.

The probability of the moiré effect in LCD displays is estimated as a function of angle based on the experimental data; a theoretical function (node spacing) is proposed basing on the distance between nodes. Both functions are close to each other. The connection between the probability of the moiré effect and the Thomae's function is also found. The function proposed in this paper can be used in the minimization of the moiré effect in visual displays, especially in autostereoscopic 3D displays.

Parallax barrier engineering for image quality improvement in an autostereoscopic 3D display.

We present a image quality improvement in a parallax barrier (PB)-based multiview autostereoscopic 3D display system under a real-time tracking of positions of a viewer's eyes. The system presented exploits a parallax barrier engineered to offer significantly improved quality of three-dimensional images for a moving viewer without an eyewear under the dynamic eye tracking. The improved image quality includes enhanced uniformity of image brightness, reduced point crosstalk, and no pseudoscopic effects. We control the relative ratio between two parameters i.e., a pixel size and the aperture of a parallax barrier slit to improve uniformity of image brightness at a viewing zone. The eye tracking that monitors positions of a viewer's eyes enables pixel data control software to turn on only pixels for view images near the viewer's eyes (the other pixels turned off), thus reducing point crosstalk. The eye tracking combined software provides right images for the respective eyes, therefore producing no pseudoscopic effects at its zone boundaries. The viewing zone can be spanned over area larger than the central viewing zone offered by a conventional PB-based multiview autostereoscopic 3D display (no eye tracking). Our 3D display system also provides multiviews for motion parallax under eye tracking. More importantly, we demonstrate substantial reduction of point crosstalk of images at the viewing zone, its level being comparable to that of a commercialized eyewear-assisted 3D display system. The multiview autostereoscopic 3D display presented can greatly resolve the point crosstalk problem, which is one of the critical factors that make it difficult for previous technologies for a multiview autostereoscopic 3D display to replace an eyewear-assisted counterpart.

Experimental observation of moiré angles in parallax barrier 3D displays.

Angles of visible moiré patterns are observed experimentally. Experiments were made across the angular range 0 - 90° in a wide range of parameters. Two kinds of clusterization were observed, ray and discrete. In rational cells (LCD pixels), the moiré patterns appear at a few fixed discrete angles. The list of preferable moiré-less angles is presented basing on the experimental data; preferable areas in the parameter space are found. The problem of minimization of the moiré effect is formulated as the Diophantine inequality with complex coefficients. The classification of moiré angles basing on the probability of the moiré effect can be practically useful.

Determination of the optimum viewing distance for a multi-view auto-stereoscopic 3D display.

We present methodologies for determining the optimum viewing distance (OVD) for a multi-view auto-stereoscopic 3D display system with a parallax barrier. The OVD can be efficiently determined as the viewing distance where statistical deviation of centers of quasi-linear distributions of illuminance at central viewing zones is minimized using local areas of a display panel. This method can offer reduced computation time because it does not use the entire area of the display panel during a simulation, but still secures considerable accuracy. The method is verified in experiments, showing its applicability for efficient optical characterization.