MDS-Net: Multi-Scale Depth Stratification 3D Object Detection from Monocular Images.

Monocular 3D object detection is very challenging in autonomous driving due to the lack of depth information. This paper proposes a one-stage monocular 3D object detection network (MDS Net), which uses the anchor-free method to detect 3D objects in a per-pixel prediction. Firstly, a novel depth-based stratification structure is developed to improve the network's ability of depth prediction, which exploits the mathematical relationship between the size and the depth in the image of an object based on the pinhole model. Secondly, a new angle loss function is developed to further improve both the accuracy of the angle prediction and the convergence speed of training. An optimized Soft-NMS is finally applied in the post-processing stage to adjust the confidence score of the candidate boxes. Experiment results on the KITTI benchmark demonstrate that the proposed MDS-Net outperforms the existing monocular 3D detection methods in both tasks of 3D detection and BEV detection while fulfilling real-time requirements.

Echinicola salinicaeni sp. nov., a novel bacterium isolated from saltern mud.

A novel gram-negative, aerobic, pink, motile, gliding, rod-shaped bacterium, designated P51T, was isolated from saline silt samples in Yantai, China. It was able to grow at 4-42 °C (optimum 33 °C), pH 4.0-9.0 (optimum 7.0), and in 0-11.0% NaCl (optimum 4.0%, w/v). It grew at 4 °C, which was lower than the minimum temperature for related strains. The genome consisted of 4111 genes with a total length of 5 139 782 bp. The 16S rRNA gene sequence analysis indicated that strain P51T was a member of the genus Echinicola and most closely related to 'Echinicola shivajiensis'. A genome analysis identified genes encoding proteins associated with carbon source utilisation, and the carotenoid biosynthesis and ß-lactam resistance pathways. Strain P51T shared an average nucleotide identity value below 84.7%, an average amino acid identity value between 70.8 and 89.3%, and a digital DNA-DNA hybridisation identity of between 17.9-28.2% with closely related type strains within the genus Echinicola. The sole menaquinone was MK-7, and the major fatty acids were iso-C15:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c), summed feature 4 (anteiso-C17:1 B and/or iso-C17:1 I), and summed feature 9 (iso-C17:1ω9c and/or 10-methyl C16:0). The polar lipids included one phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid, three unidentified aminolipids, and one unknown lipid. The phenotypic, chemotaxonomic, and phylogenetic analyses suggest that strain P51T is a novel species of the genus Echinicola, for which the name Echinicola salinicaeni sp. nov. is proposed. The type strain was P51T (KCTC 82513T = MCCC 1K04413T).

Reference Phase Stabilizer for Distributed Underwater Sonar Systems.

An optical fiber is a promising approach for data and clock transmission in distributed underwater sonar systems. However, synchronization is a critical challenge in distributed sonar systems, which mandates accurate clock synchronization down to a sub degree. Potential phase misalignment is caused by fiber length variations. In this paper, we propose a fiber-based phase stabilizer method to achieve accurate clock synchronization among sensor nodes. We use fiber-based feedback loop between sensor nodes and central station unit to monitor phase variations. Subsequently, we leverage phase shifters symmetrically arranged on the forward lane and feedback lane to compensate real-time phase variation and maintain high-precision synchronization. Besides, an ambiguity eliminator circuit is designed to remove the clock's cyclic ambiguity. Both analysis and experimental results suggest that the proposed phase stabilizer can achieve 10 MHz reference clock synchronization within 0.4 degree. We also analyze the impact of the reference clock's phase error on the system range detection accuracy, which indicates that the proposed phase stabilizer can greatly improve detection accuracy of sonar systems.

A Fast Calibration Method for Phased Arrays by Using the Graph Coloring Theory.

Phased array radars are able to provide highly accurate airplane surveillance and tracking performance if they are properly calibrated. However, the ambient temperature variation and device aging could greatly deteriorate their performance. Currently, performing a calibration over a large-scale phased array with thousands of antennas is time-consuming. To facilitate the process, we propose a fast calibration method for phased arrays with omnidirectional radiation patterns based on the graph coloring theory. This method transforms the calibration problem into a coloring problem that aims at minimizing the number of used colors. By reusing the calibration time slots spatially, more than one omnidirectional antenna can perform calibration simultaneously. The simulation proves this method can prominently reduce total calibration time and recover the radiation pattern from amplitude and phase errors and noise. It is worth noting that the total calibration time consumed by the proposed method remains constant and is negligible compared with other calibration methods.

Association between decreased serum parathyroid hormone after total thyroidectomy and persistent hypoparathyroidism.

BACKGROUND: Postoperative hypocalcemia caused by hypoparathyroidism is one of the most common morbidities of total thyroidectomy. The aim of this study was to analyze the kinetics and factors affecting PTH levels after total thyroidectomy and central neck dissection (CND). MATERIAL/METHODS: We performed a retrospective study in 438 consecutive patients who underwent total thyroidectomy between January 2007 and December 2010. No patient had a history of thyroid or neck surgery. PTH and calcium levels were recorded 1 day before the operation, during the first 5 days, and during follow-up (2 weeks and 2, 6, and 12 months). RESULTS: PTH levels declined to 41.90% of its initial value on the first day after the operation. After surgery, PTH was correlated positively with calcium and inversely with phosphate levels from postoperative day 1 to 14. Based on clinical observation, using a PTH threshold of <7 ng/L on postoperative day 1 was predictive of persistent hypoparathyroidism, with sensitivity and negative predictive value 100%, but poor specificity (70.19%). CND increased the risk of transient hypoparathyroidism compared with total thyroidectomy alone. Patients with thyroiditis had an increased risk of permanent hypoparathyroidism compared with those without thyroiditis. Iatrogenic removal of the parathyroid glands increased the risk of permanent hypoparathyroidism compared with those without iatrogenic parathyroidectomy. CONCLUSIONS: PTH declined on the first day after thyroidectomy. PTH levels <7 ng/L on the first day after surgery might be associated with persistent hypoparathyroidism. CND, thyroiditis, and iatrogenic parathyroidectomy increased the risk of hypoparathyroidism.

Incidence of metastases from 524 patients with papillary thyroid carcinoma in cervical lymph nodes posterior to the sternoclavicular joint (level VIa): Relevance for endoscopic thyroidectomy.

BACKGROUND: Dissection of central cervical lymph nodes posterior to the sternoclavicular joint is unsatisfactory in endoscopic thyroid surgery via remote access because of the barrier posed by the sternoclavicular joint. The purpose of this study was to determine the incidence and risk factors of papillary thyroid carcinoma (PTC) metastasis to the area posterior to the sternoclavicular joint. METHODS: A total of 524 patients with PTC who underwent traditional thyroid surgery form January 2012 to December 2013 were analyzed retrospectively. Their cervical lymph nodes were harvested and divided into central cervical lymph nodes cranial to the sternoclavicular joint (VIb) and those nodes posterior to the sternoclavicular joint (VIa). The VIa status was correlated with clinicopathologic factors, including sex, age, clinical N classification, comorbid thyroid disease, tumor size, extrathyroidal extension, multifocality, tumor location, and central cervical lymph node metastasis. RESULTS: The VIa metastases were detected in 138 patients (26.3%; 138 of the 524). There were a mean 3.8 lymph nodes in VIa region, and the average number of metastatic lymph nodes was 0.5. Multivariate logistic regression revealed that cN1, extrathyroidal extension, VIb positivity, tumor size greater than 0.9 cm, and tumor location in the lower third of the thyroid lobe were factors associated with VIa metastasis. CONCLUSION: Patients undergoing PTC with tumor location in the lower third of the thyroid lobe, a tumor size greater than 0.9 cm, extrathyroidal extension, or cN1 may be contraindicated for an endoscopic thyroidectomy.

[Total thyroidectomy with a modified Miccoli's approach for treatment of Graves' disease--feasibility and its applying techniques].

OBJECTIVE: To assess the feasibility and relevant applying techniques of total thyroidectomy for Graves' disease with a modified Miccoli's approach. METHODS: Forty-two patients with Graves' disease consecutively received the radical operation from June 2002 to December 2004.The modification includes: (1) Incision extending according to the degree of lobe enlargement (3-6 cm, average 4 cm); (2) A space maintain-regulating device was used to change dimensionally the volume of working space (mainly height) when specific manipulation needed; (3) A volume-reducing resection step was performed for the gland with degree III hyperplasia by cutting off the middle-inferior part of the lobe prior to endoscopic lobectomy. The approach was designed to mainly use ultrasonically-activated scalpels, with suction-dissector or others as supplementary instruments. During the operations, a method of "sequenced dissect-coagulate-cut" was employed to directly divide all branches of thyroid vessels without ligation or application of hemoclips. RESULTS: All procedures were completed successfully. None of them were converted to open surgery due to uncontrolled bleeding or severe postoperative hematoma. No severe complications occurred, except 2 cases who suffered from temporary hoarseness. CONCLUSION: Total thyroidectomy for Graves' disease can be safely performed with the modified Miccoli's approach by using ultrasonic scalpel and the space maintain-regulating device. Application of these adaptive reforms can obviously reduce the difficulties in manipulation, and thus, make the usage of this minimally invasive design also clinically possible for even radical treatment of the gland.

[Using ultrasonically activated scalpels as major instrument for vessel dividing and bleeding control in minimally invasive video-assisted thyroidectomy].

OBJECTIVE: To establish new techniques on the control of vessel dividing and bleeding in minimally invasive video-assisted thyroid surgeries. METHODS: One hundred and seventy volunteer patients with nodular goiter, adenoma and Graves' disease consecutively received the endoscopic thyroid operation according to Miccoli's mode from April 2002 to June 2003. The approach was designed to use ultrasonically activated scalpels [Harmonic Scalpel (R), Johnson & Johnson, USA] as a major, suction-dissector or others as supplementary instruments during the whole process. During the operations, two methods, "sequenced dissect-coagulate-cut" and "pre-coagulation + interlaced cut-suck-coagulate-dissect", were employed and separately evaluated for their safety or efficacy. RESULTS: All of the procedures, except that 2 (their lesions were proven to be "cancer" by frozen section and need different treatment), were successfully completed. None of them were interrupted and converted to open surgery due to uncontrolled bleeding or severe postoperative hematoma. Branches of major thyroid vessels can be directly divided by ultrasonic scalpel without ligation or using hemoclips, supposing the technique of "sequenced dissect-coagulate-cut" method was strictly used. Bleeding during intra-gland dissection can be effectively controlled by the combined techniques of precoagulation of the vessels and the capsule vessel network near and around the incision, and then, by coordinating manipulation with a special multiple functional ultrasonic scalpel and a suction-dissector, supposing the technique of "interlaced cut-suck-coagulate-dissect" was properly employed. CONCLUSIONS: Using ultrasonic scalpels as major, suction-dissector or others as supplementary instruments, manipulating cooperatively during the whole process, can be an ideal fashion in the site of a narrow gasless working space via a small single incision in anterio-inferior neck. And this may dramatically simplify the manipulation, and hence greatly reduce the operative difficulty. The reforms resolved two key technique problems in Miccoli's endoscopic operation: vessel-dividing and bleeding-control, therefore, laying a sound basis for the clinical application of this special approach.

Thyroid hemiagenesis associated with medullary or papillary carcinoma: report of cases.

BACKGROUND: Thyroid hemiagenesis is a rare congenital anomaly in which 1 thyroid lobe fails to develop. Co-occurrence of hemiagenesis and thyroid carcinoma is extremely rare. Here, we report 2 cases of thyroid hemiagenesis with carcinoma. METHODS: The first patient was referred with a left thyroid mass and absent right lobe. The frozen section examination revealed medullary thyroid carcinoma (MTC); therefore, a left thyroid lobectomy plus neck dissection was performed. Another patient was referred with a right thyroid mass and absent left lobe. Fine-needle aspiration biopsy was suspicious for papillary carcinoma. The patient underwent right thyroid lobectomy plus neck dissection. RESULTS: The operative findings confirmed hemiagenesis of the right lobe and MTC in the left lobe for the first case, and hemiagenesis of the left lobe and papillary carcinoma in the right lobe for the second case. CONCLUSION: Our case represents the first reported case of association between thyroid hemiagenesis and MTC.

[Endoscope-assisted parotidectomy for benign tumors via a short hidden auricular incision].

OBJECTIVE: To evaluate a technique of endoscope-assisted parotidectomy for benign tumor via a short hidden auricular incision. METHODS: Twenty-six volunteer patients were selected for the new approach, 16 with mixed tumor, 9 Warthin's tumor and 1 lymphoepithelial cyst. The tumor size was 1.6 approximately 3 cm (average 2.2 cm) and the incision ranged 3.5 approximately 5.5 cm(average 4.5cm) divided into two parts: 1) basic segment--started from anterio-superior crease of tragus, went downward along tragal margin and pre-earlobial fold,and stopped at earlobe root; 2) extended segment--went from earlobe root, curved down posterio-inferiorly. The length of the latter was generally not beyond 1 cm. The procedure began with raising the myo-cutaneous flap and dissecting the whole posterior portion of the gland. Thus, two working spaces needed for endoscopic manipulation could be artificially created with suitable retracting instruments. Endoscopic view was then established, and the surgeons operated continuously in the later steps. Modified techniques, such as the antegrade facial nerve dissection, retrograde great auricular nerve dissection and direct coagulate-cut method with ultrasonically activated scalpel, were employed to archive the goals of endoscopical nerve preservation and tissue resection. RESULTS: All tumors were entirely removed. No postoperative paralysis occurred, excepting 1 case who suffered from an temporary paralysis for two months. The appearance was good due to overlapping the short scar onto the irregular line of auricular contour and hiding its lowest part in the earlobe shadow. CONCLUSIONS: Parotidectomy for benign tumors could be safely done via a much-shortened incision, assisted by an endoscope. The postoperative stress of patients can be obviously reduced with the minimally invasive manipulation and the good appearance.