Experimental Investigation on Laser-Induced Electrochemical Silver Plating Technology.

The silver coating is widely used in electronic device manufacturing due to its excellent conductivity and soldering properties. Conventional preparation of local silver coating often uses the preplated silver, mask high-speed silver plating, and deplated silver processes. In this paper, the laser-induced electrodeposition technique is used to perform maskless laser-induced localized electrodeposition on a copper substrate preplated with a layer of silver. After the deplated silver process, ultrathin silver coatings with high dimensional accuracy, good corrosion resistance, and good bonding were obtained. The spatial distribution of the transient temperature field under laser irradiation is studied, the variation pattern of cathode substrate current under laser irradiation is tested, and finally, the spatial distribution of the pressure field under laser irradiation is simulated by Comsol. The effect of different laser scanning methods on the coating morphology was investigated, and the experimental study of the different single pulse energy-induced localized silver coatings was systematically carried out. The results show that the localized coating obtained by cross-line scanning with a laser single pulse energy of 93 µJ is flat with a film thickness of 0.23 µm, high dimensional accuracy, and good bonding force and corrosion resistance properties. This method provides a new approach for the preparation of a localized silver coating.

Diffusion-weighted imaging volume and diffusion-weighted imaging volume growth in acute stroke: associations with fluid-attenuated inversion recovery hyperintensities-diffusion-weighted imaging mismatch and functional outcome.

PURPOSE: This study assessed the association between diffusion-weighted imaging (DWI) volume and fluid-attenuated inversion recovery vascular hyperintensity (FVH)-DWI mismatch, functional outcome in patients with acute stroke patients receiving endovascular therapy, as well as the value of DWI volume in predicting functional outcome with stroke patients. METHODS: In 38 stroke patients who received endovascular therapy, FVH-DWI mismatch, DWI volume on admission, DWI volume on follow-up, DWI volume growth, the functional outcome at 3 months [modified Rankin scale (mRS)], and other clinical data were collected. Statistical analysis was performed to compare the associations with the above variables and predict functional outcome after stroke. RESULTS: Compared with no FVH-DWI mismatch group (n = 15), FVH-DWI mismatch group (n = 23) had a smaller DWI volume on admission (t = -2.980; P = 0.008), smaller DWI volume on follow-up (t = -2.911; P = 0.009), lower DWI volume growth (t = -2.328; P = 0.031). The 3-month outcome (1.87 ± 0.92) in patients with FVH-DWI mismatch was better than that (2.93 ± 1.62) of patients with no FVH-DWI mismatch (t = -2.307; P = 0.032). Spearman's rank correlation analysis revealed that FVH-DWI mismatch (r = 0.327; P = 0.045), DWI volume on admission (r = 0.414; P = 0.010), DWI volume on follow-up (r = 0.486; P = 0.002), and DWI volume growth (r = 0.467; P = 0.003) were positively correlated with mRS at 3 months. ROC analysis showed when the optimal cutoff value of DWI volume on admission was 33.50, the sensitivity and specificity for predicting functional outcome was 60 and 95.65%, respectively. CONCLUSIONS: Evaluating DWI volume on admission, DWI volume on follow-up as well as DWI volume growth comprehensively may be useful in predicting the functional outcome of acute stroke patients after thrombectomy.

[Imaging features of Waldeyer's ring in non-Hodgkin's lymphoma and its clinical significance].

BACKGROUND & OBJECTIVE: Waldeyer's ring is the most vulnerable site outside lymph nodes in non-Hodgkin's lymphoma (NHL). Its imaging features in NHL of early stage were similar with those of squamous epithelial cancer, which often leads to misdiagnosis. This study was to discuss imaging features of Waldeyer's ring in NHL, and its clinical significance. METHODS: CT and MRI performances of 149 patients with pathologically diagnosed Waldeyer's ring-NHL were retrospectively analyzed. RESULTS: Among 149 cases of Waldeyer's ring-NHL, 98 (65.8%) were B-cell origin, and 51 (34.2%) were T-cell or NK/T-cell origin; tonsil was the most vulnerable site followed by nasopharyngeal tonsil and other positions. CT and MRI showed that 81 were focal nodules or masses (commonly in B-cell NHL), 36 were diffuse infiltrating growth (commonly in NK/T-cell NHL), 7 were pure ulcer, and 25 were mixed type. The lesions of focal masses are characterized with even CT density and MRI signals. The lesions usually localized in pharynx-mucosa clearance, but rarely in deep space, such as parapharyngeal space, and in skull-base. Among 78 cases with involved cervical lymph nodes, 64 were B-cell origin, and 14 were NK/T-cell origin (P< 0.05). CONCLUSION: Multiple positions and centers origin, huge masses, diffuse infiltration growth, and less involvement in deep space and skull-base are typical imaging features of Waldeyer's ring-NHL; CT and MRI may be helpful to diagnose, clinical classifying, and treating Waldeyer's ring-NHL.