Direct Solution-Phase Synthesis and Functionalization of 2D WSe2 for Ambient Stability.

2H phase tungsten diselenide (WSe2 ) is a p-type 2D semiconductor from the transition metal dichalcogenides (TMDs) family with unique optoelectrical properties. Solution phase production of atomically thin WSe2 is challenging due to its instability under ambient conditions. We present a highly efficient and scalable solution method for simultaneously exfoliating and functionalizing WSe2 by leveraging the non-covalent interaction between mercapto-group and bulk WSe2 . Single and few-layer 2H phase pure WSe2 sheets of lateral size up to 5 µm with minimal basal plane defects, as revealed by XPS, Raman and FTIR spectroscopy, are produced in a water-ethanol mixture. Remarkably, WSe2 dispersion remains stable even at high concentrations (10 mg/mL) and exhibited high colloidal stability with a shelf-life exceeding a year. The findings from our study suggest that through precise manipulation of intercalation chemistry, mass production of solution-processable phase-sensitive 2D materials such as WSe2 can be achieved. This advancement holds great potential for facilitating their practical utilization in various real-world applications.

Age is a determinant factor in the susceptibility of domestic ducks to H5 clade 2.3.2.1c and 2.3.4.4e high pathogenicity avian influenza viruses.

High pathogenicity avian influenza (HPAI) is a viral disease with devastating consequences for the poultry industry worldwide. Domestic ducks are a major source of HPAI viruses in many Eurasian countries. The infectivity and pathogenicity of HPAI viruses in ducks vary depending on host and viral factors. To assess the factors influencing the infectivity and pathogenicity of HPAI viruses in ducks, we compared the pathobiology of two HPAI viruses (H5N1 clade 2.3.2.1c and H5N6 clade 2.3.4.4e) in 5- and 25-week-old ducks. Both HPAI viruses caused mortality in a dose-dependent manner (104, 106, and 108 EID50) in young ducks. By contrast, adult ducks were infected but exhibited no mortality due to either virus. Viral excretion was higher in young ducks than in adults, regardless of the HPAI strain. These findings demonstrate the age-dependent mortality of clade 2.3.2.1c and clade 2.3.4.4e H5 HPAI viruses in ducks.

Electrocatalysts for Zinc-Air Batteries Featuring Single Molybdenum Atoms in a Nitrogen-Doped Carbon Framework.

Bifunctional catalysts can facilitate two different electrochemical reactions with conflicting characteristics. Here, a highly reversible bifunctional electrocatalyst for rechargeable zinc-air batteries (ZABs) is reported featuring a "core-shell structure" in which N-doped graphene sheets wrap around vanadium molybdenum oxynitride nanoparticles. Single Mo atoms are released from the particle core during synthesis and anchored to electronegative N-dopant species in the graphitic shell. The resultant Mo single-atom catalysts excel as active oxygen evolution reaction (OER) sites in pyrrolic-N and as active oxygen reduction reaction (ORR) sites in pyridinic-N environments. ZABs with such bifunctional and multicomponent single-atom catalysts deliver high power density (≈376.4 mW cm-2 ) and long cycle life of over 630 h, outperforming noble-metal-based benchmarks. Flexible ZABs that can tolerate a wide range of temperatures (-20 to 80 °C) under severe mechanical deformation are also demonstrated.

Disinfection of various materials with 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride in hatchery facilities.

OBJECTIVE: Surface disinfection is important in the proper running of livestock farms. However, disinfection of farm equipment and facilities is difficult because they are made of different materials, besides having large surface areas and complex structures. 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (Si-QAC) is a quaternary ammonium salt-based disinfectant that attaches to various surfaces by forming covalent bonds and maintains its disinfecting capacity for a considerable time. Our aim was to evaluate the potential use of Si-QAC for disinfection of farm equipment and facilities. METHODS: The short- and long-term antimicrobial and antiviral effects of Si-QAC were evaluated in both laboratory and farm settings using modified quantitative assessment method based on the standard operating procedures of the United States Environmental Protection Agency. RESULTS: Si-QAC was highly effective in controlling the growth of the Newcastle disease virus and avian pathogenic Escherichia coli. Electron microscopy revealed that the mechanism underlying the disinfection activity of Si-QAC was associated with its ability to damage the outer membrane of the pathogen cells. In the field test, Si-QAC effectively reduced viral contamination of surfaces of equipment and space. CONCLUSION: Our results suggest that Si-QAC has great potential as an effective chemical for disinfecting farm equipment and facilities. This disinfectant could retain its disinfection ability longer than other commercial disinfectants and contribute to better farm biosecurity.

Efficacy of hook-type locking plate and partially threaded cancellous lag screw in the treatment of displaced medial malleolar fractures in elderly patients.

INTRODUCTION: Traditionally, partially threaded cancellous lag screws (PTCS) are used for most medial malleolar fractures but are often challenging to execute in elderly patients because of the high risk of postoperative complications. Limited literature explores whether hook-type locking compression plates (LCPs) reliably offer better outcomes than PTCS in elderly patients. We aimed to compare the midterm radiologic and clinical outcomes between hook-type LCP and PTCS for medial malleolar fractures in an elderly population. METHODS: We included 258 patients, aged 65 years and above, treated with either a hook-type locking plate (hook LCP group: 121 patients) or PTCS (screw group: 137 patients), and with follow-ups of at least 36 months in this retrospective study. Radiographic assessments included the union rate and interval to fracture union. Clinical assessment included the postoperative complications and revision procedures. RESULTS: Although a significantly higher rate of comminuted fractures was observed in the hook LCP group than in the screw group (p < .001), no significant difference in the union rate was observed between the two groups (hook LCP group: 93.4% vs. screw group: 89.8%, p = .151), and a significantly shorter interval to union was observed in the hook LCP group (10.2 ± 7.0 vs. 12.3 ± 6.7 weeks, p = .015). There was a trend toward a lower rate of complications, including revision procedures, in the hook LCP group than in the screw group (19.9% vs. 28.5%, p = .107 and 6.6% vs. 13.8%, p = .074). CONCLUSION: Hook-type LCP may be an alternative option for treating medial malleolar fractures with comminution in elderly patients.

The Microvillar and Solitary Chemosensory Cells as the Novel Targets of Infection of SARS-CoV-2 in Syrian Golden Hamsters.

Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019, suffer from respiratory and non-respiratory symptoms. Among these symptoms, the loss of smell has attracted considerable attention. The objectives of this study were to determine which cells are infected, what happens in the olfactory system after viral infection, and how these pathologic changes contribute to olfactory loss. For this purpose, Syrian golden hamsters were used. First, we verified the olfactory structures in the nasal cavity of Syrian golden hamsters, namely the main olfactory epithelium, the vomeronasal organ, and their cellular components. Second, we found angiotensin-converting enzyme 2 expression, a receptor protein of SARS-CoV-2, in both structures and infections of supporting, microvillar, and solitary chemosensory cells. Third, we observed pathological changes in the infected epithelium, including reduced thickness of the mucus layer, detached epithelia, indistinct layers of epithelia, infiltration of inflammatory cells, and apoptotic cells in the overall layers. We concluded that a structurally and functionally altered microenvironment influences olfactory function. We observed the regeneration of the damaged epithelium, and found multilayers of basal cells, indicating that they were activated and proliferating to reconstitute the injured epithelium.

Thermal Image Scanning for the Early Detection of Fever Induced by Highly Pathogenic Avian Influenza Virus Infection in Chickens and Ducks and Its Application in Farms.

Highly pathogenic avian influenza (HPAI) is considered as one of the most devastating poultry diseases. It is imperative to immediately report any known outbreaks to the World Organization for Animal Health. Early detection of infected birds is of paramount importance to control virus spread, thus minimizing the associated economic loss. In this study, thermal imaging camera devices were used to detect change in the maximum surface temperature (MST) of chickens (n = 5) and ducks (n = 2) as an early indicator of experimental HPAI infection. The MST of both chickens and ducks increased at least 24 h before the manifestation of clinical signs of HPAI infection, depending on the severity of the infection. The basal MST was recorded for broiler chickens housed under small pen and normal farm conditions without intentional infection. A threshold cutoff of MST was established based on the circadian rhythm of normal MST. This study suggests that thermal imaging of chickens and ducks is a promising tool to screen any potential HPAI-infected flock in order to expedite HPAI diagnosis.

COMPARING OUTCOMES OF THE ANKLE ARTHRODESIS BY USING TWO DIFFERENT MATERIALS VIA A TRANSFIBULAR APPROACH.

OBJECTIVE: To compare clinical and radiologic results and complications of patients who underwent arthrodesis using a transfibular approach with either a cannulated screw or an anterior fusion plate. METHODS: Patients who underwent ankle arthrodesis were divided into two groups according to the used materials: 6.5 mm cannulated screw (A) and anterior fusion plate (B). The clinical scores were compared between groups. The radiologic results were then assessed by union time. The results were statistically analyzed using SPSS 20. RESULTS: There was no significant difference between both groups in the American Orthopedic Foot & Ankle Society (AOFAS) score (p = 0.75), and in the visual analog scale (p = 0.42). In group B, two cases included wound infection at the surgical site. In tt A, the mean union time was 10.5 ± 2.3 weeks. In group B, it was 7.8 ± 1.3. There was a statistically significant difference (p = 0.007) between union time in both groups. CONCLUSION: Anterior fusion plate is an effective method for shorter union time, but the surgeon should be careful with the surgical wound at the skin incision site in the lesion of the distal tibia. Level of Evidence III, Retrospective comparative study.

OBJETIVO: Comparar os resultados clínicos e radiológicos assim como as complicações de pacientes sujeitos a artrodese de abordagem transfibular com o uso de parafuso canulado ou placa óssea anterior. MÉTODOS: Pacientes sujeitos a artrodese do tornozelo foram divididos em dois grupos de acordo com os materiais usados: parafuso canulado de 6,5 mm (A) e placa óssea anterior (B). Os escores clínicos de ambos os grupos foram comparados e os resultados radiológicos foram avaliados de acordo com o tempo de união óssea. Os resultados foram analisados estatisticamente usando SPSS 20. RESULTADOS: Não houve diferença significativa entre os grupos quanto ao escore American Orthopedic Foot & Ankle Society (AOFAS) (p = 0,75) e a escala visual analógica (p = 0,42). No grupo B, ocorreu infecção na área da cirurgia em dois casos. No grupo A, a média de tempo de união foi de 10,5 ± 2,3 semanas. No grupo B, este foi de 7,8 ± 1,3. Constatou-se diferença estatisticamente significante (p = 0,007) quanto ao tempo de união em ambos os grupos. CONCLUSÃO: Os autores concluíram que a placa óssea anterior é um método eficiente para tempos de união curtos, porém o cirurgião deve ficar atento à ferida cirúrgica na área de incisão da pele em casos de lesão na tíbia distal. Nível de Evidência III, Estudo retrospectivo comparativo.

Comparing outcomes of the ankle arthrodesis by using two different materials via a transfibular approach / Comparação dos resultados da artrodese do tornozelo usando dois diferentes materiais através de uma abordagem transfibular

ABSTRACT Objective: To compare clinical and radiologic results and complications of patients who underwent arthrodesis using a transfibular approach with either a cannulated screw or an anterior fusion plate. Methods: Patients who underwent ankle arthrodesis were divided into two groups according to the used materials: 6.5 mm cannulated screw (A) and anterior fusion plate (B). The clinical scores were compared between groups. The radiologic results were then assessed by union time. The results were statistically analyzed using SPSS 20. Results: There was no significant difference between both groups in the American Orthopedic Foot & Ankle Society (AOFAS) score (p = 0.75), and in the visual analog scale (p = 0.42). In group B, two cases included wound infection at the surgical site. In tt A, the mean union time was 10.5 ± 2.3 weeks. In group B, it was 7.8 ± 1.3. There was a statistically significant difference (p = 0.007) between union time in both groups. Conclusion: Anterior fusion plate is an effective method for shorter union time, but the surgeon should be careful with the surgical wound at the skin incision site in the lesion of the distal tibia. Level of Evidence III, Retrospective comparative study.

RESUMO Objetivo: Comparar os resultados clínicos e radiológicos assim como as complicações de pacientes sujeitos a artrodese de abordagem transfibular com o uso de parafuso canulado ou placa óssea anterior. Métodos: Pacientes sujeitos a artrodese do tornozelo foram divididos em dois grupos de acordo com os materiais usados: parafuso canulado de 6,5 mm (A) e placa óssea anterior (B). Os escores clínicos de ambos os grupos foram comparados e os resultados radiológicos foram avaliados de acordo com o tempo de união óssea. Os resultados foram analisados estatisticamente usando SPSS 20. Resultados: Não houve diferença significativa entre os grupos quanto ao escore American Orthopedic Foot & Ankle Society (AOFAS) (p = 0,75) e a escala visual analógica (p = 0,42). No grupo B, ocorreu infecção na área da cirurgia em dois casos. No grupo A, a média de tempo de união foi de 10,5 ± 2,3 semanas. No grupo B, este foi de 7,8 ± 1,3. Constatou-se diferença estatisticamente significante (p = 0,007) quanto ao tempo de união em ambos os grupos. Conclusão: Os autores concluíram que a placa óssea anterior é um método eficiente para tempos de união curtos, porém o cirurgião deve ficar atento à ferida cirúrgica na área de incisão da pele em casos de lesão na tíbia distal. Nível de Evidência III, Estudo retrospectivo comparativo.

Quantifying the depth of anesthesia based on brain activity signal modeling.

Various methods of assessing the depth of anesthesia (DoA) and reducing intraoperative awareness during general anesthesia have been extensively studied in anesthesiology. However, most of the DoA monitors do not include brain activity signal modeling. Here, we propose a new algorithm termed the cortical activity index (CAI) based on the brain activity signals. In this study, we enrolled 32 patients who underwent laparoscopic cholecystectomy. Raw electroencephalography (EEG) signals were acquired at a sampling rate of 128 Hz using BIS-VISTA with standard bispectral index (BIS) sensors. All data were stored on a computer for further analysis. The similarities and difference among spectral entropy, the BIS, and CAI were analyzed. Pearson correlation coefficient between the BIS and CAI was 0.825. The result of fitting the semiparametric regression models is the method CAI estimate (-0.00995; P = .0341). It is the estimated difference in the mean of the dependent variable between method BIS and CAI. The CAI algorithm, a simple and intuitive algorithm based on brain activity signal modeling, suggests an intrinsic relationship between the DoA and the EEG waveform. We suggest that the CAI algorithm might be used to quantify the DoA.

Improvement of PR8-Derived Recombinant Clade 2.3.4.4c H5N6 Vaccine Strains by Optimization of Internal Genes and H103Y Mutation of Hemagglutinin.

Clade 2.3.4.4c H5N6 avian influenza A viruses (AIVs) may have originally adapted to infect chickens and have caused highly pathogenic avian influenza (HPAI) in poultry and human fatalities. Although A/Puerto Rico/8/1934 (H1N1) (PR8)-derived recombinant clade 2.3.4.4c H5N6 vaccine strains have been effective in embryonated chicken eggs-based vaccine production system, they need to be improved in terms of immunogenicity and potential mammalian pathogenicity. We replaced the PB2 gene alone or the PB2 (polymerase basic protein 2), NP (nucleoprotein), M (matrix protein) and NS (non-structural protein) genes together in the PR8 strain with corresponding genes from AIVs with low pathogenicity to remove mammalian pathogenicity and to match CD8+ T cell epitopes with contemporary HPAI viruses, respectively, without loss of viral fitness. Additionally, we tested the effect of the H103Y mutation of hemagglutinin (HA) on antigen productivity, mammalian pathogenicity and heat/acid stability. The replacement of PB2 genes and the H103Y mutation reduced the mammalian pathogenicity but increased the antigen productivity of the recombinant vaccine strains. The H103Y mutation increased heat stability but unexpectedly decreased acid stability, probably resulting in increased activation pH for HA. Interestingly, vaccination with inactivated recombinant virus with replaced NP, M and NS genes halted challenge virus shedding earlier than the recombinant vaccine without internal genes replacement. In conclusion, we successfully generated recombinant clade 2.3.4.4c H5N6 vaccine strains that were less pathogenic to mammals and more productive and heat stable than conventional PR8-derived recombinant strains by optimization of internal genes and the H103Y mutation of HA.

Bioengineering a highly productive vaccine strain in embryonated chicken eggs and mammals from a non-pathogenic clade 2·3·4·4 H5N8 strain.

The clade 2·3·4·4 H5Nx is a highly pathogenic avian influenza (HPAI) virus, which first appeared in China and has spread worldwide since then, including Korea. It is divided into subclades a - d, but the PR8-derived recombinant clade 2·3·4·4 a viruses replicate inefficiently in embryonated chicken eggs (ECEs). High virus titer in ECEs and no mammalian pathogenicity are the most important prerequisites of efficacious and safer vaccine strains against HPAI. In this study, we have synthesized hemagglutinin (HA) and neuraminidase (NA) genes based on the consensus amino acid sequences of the clade 2·3·4·4a and b H5N8 HPAIVs, using the GISAID database. We generated PR8-derived H5N8 recombinant viruses with single point mutations in HA and NA, which are related to efficient replication in ECEs. The H103Y mutation in HA increased mammalian pathogenicity as well as virus titer in ECEs, by 10-fold. We also successfully eradicated mammalian pathogenicity in H103Y-bearing H5N8 recombinant virus by exchanging PB2 genes of PR8 and 01310 (Korean H9N2 vaccine strain). The final optimized H5N8 vaccine strain completely protected against a heterologous clade 2·3·4·4c H5N6 HPAIV in chickens, and induced hemagglutination inhibition (HI) antibody in ducks. However, the antibody titer of ducks showed age-dependent results. Thus, H103Y and 01310PB2 gene have been successfully applied to generate a highly productive, safe, and efficacious clade 2·3·4·4 H5N8 vaccine strain in ECEs.

Photosensitive Graphene P-N Junction Transistors and Ternary Inverters.

We investigate the electric transport in a graphene-organic dye hybrid and the formation of p-n junctions. In the conventional approach, graphene p-n junctions are produced by using multiple electrostatic gates or local chemical doping, which produce different types of carriers in graphene. Instead of using multiple gates or typical chemical doping, a different approach to fabricate p-n junctions is proposed. The approach is based on optical gating of photosensitive dye molecules; this method can produce a well-defined sharp junction. The potential difference in the proposed p-n junction can be controlled by varying the optical power of incident light. A theoretical calculation based on the effective medium theory is performed to thoroughly explain the experimental data. The characteristic transport behavior of the photosensitive graphene p-n junction opens new possibilities for graphene-based devices, and we use the results to fabricate ternary inverters. Our strategy of building a simple hybrid p-n junction can further offer many opportunities in the near future of tuning it for other optoelectronic functionalities.

Molecular characterization and genetic diversity of avian paramyxovirus type 4 isolated in South Korea from 2013 to 2017.

In recent years, avian paramyxovirus type 4 (APMV-4) frequently isolated from wild and domestic bird populations particularly waterfowls worldwide. However, molecular characteristics and genetic diversity of APMV-4 are uncertain, owing to the limited availability of sequence information. A total of 11 APMV-4 strains from 9850 fecal, swab, and environmental samples were isolated during the surveillance program in wintering seasons of 2013-2017 in South Korea. We performed genetic characterization and phylogenetic analysis to investigate the genetic diversity and relatedness between isolates from the region. We report high APMV-4 genetic diversity (multiple genotypes and sub-genotypes) among wild bird and poultry populations in Korea and that the potential virus exchange occurs between neighboring countries via wild bird migration. Furthermore, our study results suggest the possibility of transcontinental transmission of APMV-4 between Asia and Europe.

Molecular Characterization of Avian Paramyxovirus Types 4 and 8 Isolated from Wild Migratory Waterfowl in Mongolia.

Avian paramyxoviruses (APMVs) constitute some of the most globally prevalent avian viruses and are frequently isolated from wild migratory bird species. Using 1,907 fresh fecal samples collected during the 2012 avian influenza surveillance program, we identified two serotypes of APMV: APMV-4 ( n=10) and APMV-8 ( n=1). Sequences for these isolates phylogenetically clustered with Asian APMV-4 and APMV-8 recently isolated from wild birds in Korea, Japan, China, and Kazakhstan. Analysis by DNA barcoding indicated that the Mongolian APMV-4 and APMV-8 strains were isolated from Anseriformes species including Mallards ( Anas platyrhynchos) and Whooper Swans ( Cygnus cygnus). The close genetic relatedness to Asian isolates, and to similar host species, suggested that wild bird species in the Anatidae family might play an important role as a natural reservoir in the spread of APMV-4 and APMV-8. However, we did not find conclusive evidence to support this hypothesis owing to the limited number of strains that could be isolated. Enhanced surveillance of poultry and wild bird populations in Asia is therefore crucial for the understanding of global AMPV transmission, ecology, evolution, and epidemiology.

Comparison of the Outcomes Between Headless Cannulated Screw Fixation and Fixation Using a Locking Compression Distal Ulna Hook Plate in Fracture of Fifth Metatarsal Base.

The aim of the present study was to evaluate and compare the clinical and radiologic results of internal fixation with a headless cannulated screw versus a locking compression distal ulna hook plate for fractures at the base of the fifth metatarsal bone, zone 1. From April 2012 to April 2015, 30 cases (29 patients) were retrospectively evaluated. The mean follow-up period was 13 months. The patients were divided into 2 groups stratified by the fixation method: screw (group A, n = 15) or plate (group B, n = 15). We measured the displacement to diastasis of the fracture on the foot oblique radiographs taken pre- and postoperatively in each group, recorded the time to bony union, and measured the difference in the reduction distance in each group. The clinical results were evaluated using the American Orthopaedic Foot and Ankle Society midfoot score at 12 months postoperatively. In group A, the mean interval to union was 54.2 ± 9.3 days, the mean displacement to diastasis had improved to 0.3 ± 0.4 mm postoperatively (p < .001), and the mean reduction distance was 2.9 ± 1.0 mm postoperatively. In group B, the mean interval to union was 41.5 ± 7.0 days, the mean displacement to diastasis had improved to 0.06 ± 0.2 mm postoperatively (p < .001), and the mean reduction distance was 4.1 ± 1.6 mm. The American Orthopaedic Foot and Ankle Society midfoot scale score was 97.7 ± 3.4 in group A and 98.2 ± 3.2 in group B. The interval to union was significantly different between the 2 groups (p = .01). No complications were recorded. Our findings have shown that the plate is a reasonable and alternative method for the surgical treatment of fifth metatarsal base fractures.

Complete Genome Sequence of an Avian Paramyxovirus Type 4 Strain Isolated from Domestic Duck at a Live Bird Market in South Korea.

We report here the first full-genome sequence of an avian paramyxovirus type 4 (APMV-4) strain isolated from a domestic mallard duck at a live bird market in South Korea. Phylogenetic analyses provide genetic information on a new genetic clade, APMV-4, isolated from a domestic duck and evidence of APMV-4 exchange between poultry and wild birds.

Extremely low-frequency electromagnetic field promotes astrocytic differentiation of human bone marrow mesenchymal stem cells by modulating SIRT1 expression.

It has been shown that extremely low-frequency electromagnetic fields (ELFMF) affect regulation of cell fate and differentiation. Thus, the aim of this study was to investigate the role of ELFMFs in the enhancement of astrocytic differentiation. ELFMF exposure reduced the rate of proliferation and enhanced astrocytic differentiation. The ELFMF-treated cells showed increased levels of the astrocyte marker (GFAP), while those of the early neuronal marker (Nestin) and stemness marker (OCT3/4) were downregulated. The reactive oxygen species (ROS) level was observed to be significantly elevated after ELFMF exposure, which strengthens the modulatory role of SIRT1 and SIRT1 downstream molecules (TLE1, HES1, and MASH1) during astrocytic differentiation. After nicotinamide (5 mM) mediated inhibition of SIRT1, levels of TLE1, HES1, and MASH1 were examined; TLE1 was significantly upregulated and MASH1 was downregulated. These results suggest that ELFMFs induce astrocytic differentiation through activation of SIRT1 and SIRT1 downstream molecules.

Primary synovial chondromatosis of the talonavicular joint: A case report.

Synovial chondromatosis developes by metaplasia of the synovial cells in the synovium of joints, and is a benign synovial tumor with multiple cartilaginous nodules. It is most commonly found in single and large joints, such as the knee, hip, and shoulder. Occurrence in the foot and ankle is uncommon, although there have been previous reports in the orthopedic and radiological literature of primary synovial chondromatosis in the subtalr, calcaneocuboid, naviculocuneiform, and metatarsaophalangeal joints. To our knowledge, occurrence in the talonavicular joint is even rarer, with only one report in the literature to date. Here, we report a case of synovial chondromatosis of the talonavicular joint, alongside a review of the literature.

Interfacial Reaction Characteristics of Au Stud/Sn/Cu Pillar Bump During Annealing and Current Stressing.

In this work, intermetallic compound (IMC) growth behavior in Au stud/Sn/Cu pillar bumps was investigated under annealing and current stressing conditions. AuSn2 and AuSn4 IMCs formed at the interface between the Au studs and Sn after bonding. The AuSn2 phase grew significantly as the stressing time increased, causing micro-voids to form near the (Cu, Au)6Sn5, AuSn2 and AuSn4 IMC interfaces. The interfacial reactions resulting from current stressing took place quicker than observed for pure annealing. The apparent activation energies for the growth of the AuSn2 phase during annealing and current stressing were 0.52 eV and 0.47 eV, respectively, which may be closely related to the acceleration of the interfacial reaction by electron wind forces during current stressing.