Systematic study of elliptic flow parameter in the relativistic nuclear collisions at RHIC and LHC energies

We employed the new issue of a parton and hadron cascade model PACIAE 2.1 to systematically investigate the charged particle elliptic flow parameter $v_2$ in the relativistic nuclear collisions at RHIC and LHC energies. With randomly sampling the transverse momentum $x$ and $y$ components of the particles generated in string fragmentation on the circumference of an ellipse instead of circle originally, the calculated charged particle $v_2(\eta)$ and $v_2(p_T)$ fairly reproduce the corresponding experimental data in the Au+Au/Pb+Pb collisions at $\sqrt{s_{NN}}$=0.2/2.76 TeV. In addition, the charged particle $v_2(\eta)$ and $v_2(p_T)$ in the p+p collisions at $\sqrt s$=7 TeV as well as in the p+Au/p+Pb collisions at $\sqrt{s_{NN}}$=0.2/5.02 TeV are predicted.Comment: 7 pages, 5 figure

Undifferentiated (Spindle Cell) Pancreatic Carcinoma: A Case Report with Osteochondroid Differentiation

Context Undifferentiated (spindle cell) carcinomas of the pancreas are rare anaplastic variants of pancreatic ductal adenocarcinoma with a frequency of 2% of pancreatic exocrine tumors. Their clinicopathological features are limited and obtained by few previously case reports. We report a case of undifferentiated pancreatic carcinoma with a rare focal osteochondroid differentiation. Case report A sixty-six-year-old woman was admitted to our hospital for abdominal pain and nonspecific nausea for almost 40 days. Imaging studies revealed a well-defined cystic–solid mass with heterogeneous density involving the tail of the pancreas. We performed an en bloc distal pancreatectomy with splenectomy for radical excision, as well as regional lymphadenectomy. The resected specimen revealed a 4.0×5.0 cm exophytic clear-bordered neoplasm of the tail of the pancreas containing necrotic and calcified areas, without splenic invasion. The lymph node involvement was not detected (0/5) and the surgical margins were negative. Microscopy showed pleomorphism with giant cells, spindle-shaped cells with anaplasia, and osteochondroid differentiation. A diagnosis of undifferentiated (spindle cell) carcinoma of the pancreas with focal osteochondroid differentiation was made. The patient declined chemotherapy and extended lymphadenectomy. She suffered from liver and lymph nodes metastasis 9 months after surgery, and she subsequently died 4 months later due to high tumor burden. Conclusions Undifferentiated pancreatic carcinoma with osteochondroid differentiation is rare but associated with extremely poor prognosis. It should be included in the differential diagnosis of pancreatic mass lesions.Image: Ossification in the tumor edge

Ovarian Steroid Cell Tumors, Not Otherwise Specified: Analysis of Nine Cases With a Literature Review

BACKGROUND: Ovarian steroid cell tumors (SCTs), not otherwise specified (NOS), are rare, with few large studies. The purpose of this study was to analyze the clinical features, prognosis, and treatment choices for these patients of different age groups. METHODS: This was a retrospective study. We identified nine cases of ovarian steroid cell tumor, not otherwise specified, confirmed by post-operative histopathological examination, and analyzed clinical features, surgical procedures, and follow up outcomes. We also reviewed cases reports of ovarian steroid cell tumors, not otherwise specified. RESULTS: A total of nine cases were included. The age range was 9-68 years (mean, 41.89 ± 19.72 years). Clinical features included virilization, amenorrhea, abdominal pain, vaginal bleeding, isosexual precocious puberty, Cushing\u27s syndrome, and abnormal weight gain with elevated testosterone levels. The follow up interval ranged 5-53 months and no recurrence was observed. CONCLUSION: Ovarian steroid cell tumors covered all age groups, with manifestations of androgen excess. Younger patients appeared to have a more favorable prognosis, which provided more opportunities for these patients to pursue treatment options that will preserve reproductive function

Active Learning on a Programmable Photonic Quantum Processor

Training a quantum machine learning model generally requires a large labeled dataset, which incurs high labeling and computational costs. To reduce such costs, a selective training strategy, called active learning (AL), chooses only a subset of the original dataset to learn while maintaining the trained model's performance. Here, we design and implement two AL-enpowered variational quantum classifiers, to investigate the potential applications and effectiveness of AL in quantum machine learning. Firstly, we build a programmable free-space photonic quantum processor, which enables the programmed implementation of various hybrid quantum-classical computing algorithms. Then, we code the designed variational quantum classifier with AL into the quantum processor, and execute comparative tests for the classifiers with and without the AL strategy. The results validate the great advantage of AL in quantum machine learning, as it saves at most $85\%$ labeling efforts and $91.6\%$ percent computational efforts compared to the training without AL on a data classification task. Our results inspire AL's further applications in large-scale quantum machine learning to drastically reduce training data and speed up training, underpinning the exploration of practical quantum advantages in quantum physics or real-world applications

catena-Poly[[[diaqua­iron(II)]-μ-pyridine-2,5-dicarboxyl­ato-[tetra­aqua­iron(II)]-μ-pyridine-2,5-dicarboxyl­ato] tetra­hydrate]

In the crystal structure of the title compound, {[Fe2(C7H3NO4)2(H2O)6]·4H2O}n, there are two types of coordination for the FeII atoms. One FeII atom is in a distorted octa­hedral N2O4 environment, with two chelating rings from the pyridine­dicarboxyl­ate ligands and two O atoms from the water mol­ecules, while the other is in a distorted octa­hedral O6 environment with two O atoms from the pyridine­dicarboxyl­ate ligands and four O atoms from the water mol­ecules. Both FeII atoms lie on crystallographic centers of symmetry. The complex possesses an infinite chain structure running along the [101] direction. These chains are inter­connected by the uncoordinated water mol­ecules through O—H⋯O hydrogen bonds