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Li-Juan Hu,1 Zhong Mei,1,2 Yan-Ping Shen,1 Hao-Tian Sun,1 Zhi-Min Sheng,1 Xin-Zhong Chen,1 Xiao-Wei Qian1 1Department of Anesthesiology, Women’s Hospital, Zhejiang University School of Medicine, Hangzhou, People’s Republic of China; 2Department of Anesthesiology, Affiliated Xiaoshan Hospital, Hangzhou Normal University, Hangzhou, People’s Republic of ChinaCorrespondence: Xiao-Wei Qian, Department of Anesthesiology, Women’s Hospital, Zhejiang University School of Medicine, Xueshi Road 1, Hangzhou, 310006, People’s Republic of China, Tel +86-571-87061501, Fax +86 571 87061878, Email qianxw@zju.edu.cnBackground: It is well-known that severe preeclamptic parturients have less vasopressor requirements than normotensive parturients; however, the exact dose difference is poorly documented. This study aimed to determine and compare the ED50 and ED90 of a single bolus phenylephrine for the treatment of spinal anesthesia-induced hypotension in parturients with severe preeclampsia and parturients with normotension.Methods: Seventy-five parturients with severe preeclampsia scheduled for cesarean delivery under combined spinal-epidural anesthesia were enrolled and randomly allocated to receive a single bolus of phenylephrine at five different doses (40, 50, 60, 70, and 80 μg), whereas 75 parturients with normotension were randomized to receive a single bolus of phenylephrine at five different doses (70, 80, 90, 100, and 110 μg) for the treatment of the first episode of hypotension. Phenylephrine dose values were log-transformed, the proportions of the successful interventions at each dose were converted to probits, and regression analysis was performed.Results: The ED50 and ED90 (95% CI) of bolus phenylephrine were 72.1 (61.7 to 79.9) μg and 107 (95.9– 128.6) μg in parturients with normotension. The ED50 and ED90 values in parturients with severe preeclampsia were 47.6 (41.3– 52.7) μg and 70.7 (62.9– 86.7) μg. The relative median potency was 1.51 (1.16– 2.61).Conclusion: Under this study conditions, severe preeclamptic parturients required a 34% reduction of ED50 of phenylephrine dose compared with normotensive parturients.Keywords: cesarean delivery, spinal anesthesia, hypotension, phenylephrine, preeclampsia

Previous studies have shown that prophylactic norepinephrine infusion is superior to intermittent bolus administration in preventing post-spinal hypotension. Nevertheless, it is still controversial whether manually-controlled variable-rate infusion is more effective than fixed-rate infusion. The purpose of the present study was to compare the efficacy of variable-rate infusion and fixed-rate infusion of norepinephrine for prophylaxis against maternal hypotension and maintaining hemodynamic stability during spinal anesthesia for cesarean delivery to determine more effective mode for clinical practice.A prospective randomized, controlled study.Operating room, Women's Hospital, Zhejiang University School of Medicine.A total of 161 parturients scheduled for elective cesarean delivery with spinal anesthesia were randomized into Group F (fixed-rate infusion) and Group V (variable-rate infusion).Parturients received prophylactic norepinephrine infusion concurrent with the intrathecal injection at rate started at 0.05 μg/kg/min. In Group F, norepinephrine was administered continuously at a fixed (on-off) rate, and a bolus of norepinephrine 5 μg or 10 μg was given when systolic blood pressure (SBP) decreased by 20% or more of baseline. In Group V, manually adjusted norepinephrine infusion within the range 0-0.14 μg/kg/min, according to SBP at 1-min intervals until delivery, aim to maintain values close to the baseline.During the study period, the incidence of maternal hypotension, hemodynamic performance, the number of physician interventions, reactive hypertension, bradycardia, nausea, vomiting, norepinephrine cumulative dose (before delivery), and neonatal outcomes were recorded.The incidence of maternal hypotension was significantly lower in Group V than that in Group F (9% versus 30%) (P 0.001). No significant difference was found in the serial changes in SBP and heart rate (HR) for the first 15 min. Group V showed higher frequency of physician interventions compared with the Group F (P 0.001). The incidence of hypertension, severe hypotension, nausea, vomiting, bradycardia, norepinephrine cumulative dose, and neonatal outcome were comparable between the two groups.When norepinephrine was infused at an initial dose of 0.05 μg/kg/min for preventing hypotension during spinal anesthesia for cesarean delivery, due to technical limitations of inadequate dose design in this study, neither a variable-rate infusion (need more physician intervention) nor a fixed-rate infusion regimen (experience more transient hypotension) was optimal. However, in terms of clinical importance, how to prevent the parturients from experiencing more incidence of hypotension might be a greater concern for anesthesiologists.

Background: Although several previous studies demonstrated the feasibility and efficacy of indocyanine green (ICG) for thyroid cancer surgery, ICG was administered through venous injection and focused on parathyroid gland protection. We thus aimed to study the feasibility of imaging using ICG combined with carbon nanoparticles (CNs) in the identification of sentinel lymph nodes (SLNs) in patients diagnosed with papillary thyroid microcarcinoma (PTMC). Methods: Two approaches were applied to detect lymph nodes in PTMC surgery. Patients were randomized into 2 groups. ICG and CNs were injected into the thyroid in Group A. In Group B, only CNs was injected. Black-stained or fluorescent nodes observed using near-infrared fluorescence imaging systems were defined as SLNs. SLN and central lymph node (CLN) dissection was completed in both groups. The pathological and postoperative outcomes were compared between 2 groups. Results: There were 40 patients in Group A and 60 in Group B. A total of 138 SLNs were identified; 72 and 66 SLNs were detected and dissected in Groups A and B, respectively. The number of SLNs identified (per patient) in Group A was higher than that in Group B (P = .027). The number of harvested CLNs was 161 and 192 in Groups A and B, respectively, out of which 45 and 48 lymph nodes with metastasis were confirmed by permanent pathology. The CLN metastatic rate in Group A was higher than that in Group B (P = .048). Conclusion: Imaging using ICG combined CNs is feasible and safe for SLN identification in PTMC patients. Compared with using only CNs, more SLNs can be removed and more metastatic lymph nodes can be confirmed when using the combined method. Although the combined method appears to accurately stage tumors, further research is needed.

We present a novel cavity engineering work – we named this cavity as dual-curvature cavity, which improves pFET electrical performance. This new cavity shape design minimizes the source/drain leakage penalty from deeper cavity depth while enabling the transistor performance benefits from larger eSiGe. In addition, this new cavity shape minimizes the penalty of deeper cavity on SDB (single diffusion break) devices through minimizing the facet effect in SDB structure. This work demonstrates that this new cavity shape could improve p-type transistor performance by 4{\%} on top of the Fin shape optimization.

In order to extract characteristic values of graphene, a method based on a series of digital image processing algorithms was proposed in this paper. Using the method, we can automatically analyze topology structure and calculate amount of carbon atoms, and even calculate chiral vector indices (n, m) during in-situ TEM scanning of graphene. At last, we also write the correlative software with c++, which applying the digital image processing algorithms, and give out the processing result of several classic TEM image of graphene.

We present a method to form a spacer-confined cavity to enable the deeper cavity for performance improvement while keeping the lateral width of epitaxial silicon doped with phosphorous (SiP EPI) from creating an EPI bridging issue. An extra non-selective etch step is introduced to leave the sidewall spacer but etch away the Si fin. The SiP EPI is confined between the sidewall spacer for EPI lateral width control. In this work, TCAD simulation shows that the effective gate length (Leff) near the bottom of the fin decreases when cavity depth increases. The deeper junction provides another performance boost on top of the performance improvement from the fin height increase. In addition, the spacer-confined cavity demonstrates a 6% device performance improvement with comparable drain-induced-barrier-lowering at +8 nm cavity depth. The device performance starts saturation when the cavity depth extends beyond +15 nm. The spacer-confined cavity offers a solution to increase cavity depth without suffering from the EPI bridging issue for advance finFET technology.

As the size of the semiconductor device continues to shrink, two integration approaches are used for gate module; (1) gate first, and (2) gate last. The gate last approach requires removal of thin (10–30Å) titanium nitride (TiN) diffusion blocking layers during the “replacement” process after the poly-Si layer is removed. An etch rate study was conducted to evaluate the selectivity of a combined aqueous/solvent cleaning chemistry at various temperatures on blanket TiN and TaN wafers to identify the optimum operating regime. A significant improvement of yield with the application of the new cleaning approach has been observed.