SPECIAL VALUES OF THE BELL POLYNOMIALS OF THE SECOND KIND FOR SOME SEQUENCES AND FUNCTIONS: Special values of Bell polynomials of second kind

In the paper, the authors concisely review some closed formulas and applications of special values of the Bell polynomials of the second kind for some special sequences and elementary functions, explicitly present closed formulas for those sequences investigated in [F. T. Howard, A special class of Bell polynomials, Math. Comp. 35 (1980), no. 151, 977–989; Available online at https://doi.org/10.2307/2006208], and newly establish some closed formulas for some special values of the Bell polynomials of the second kind

An intelligent cluster-based routing scheme in 5G flying ad hoc networks

Flying ad hoc network (FANET) is an application of 5G access network, which consists of unmanned aerial vehicles or flying nodes with scarce resources and high mobility rates. This paper proposes a deep Q-network (DQN)-based vertical routing scheme to select routes with higher residual energy levels and lower mobility rates across network planes (i.e., macro-plane, pico-plane, and femto-plane), which has not been investigated in the literature. The main motivation behind this work is to address frequent link disconnections and network partitions in order to enhance network performance. The 5G access network has a central controller (CC) and distributed controllers (DCs) in different network planes. The proposed scheme is a hybrid approach that allows CC and DCs to exchange information among themselves, and handle global and local information, respectively. The proposed scheme is suitable for highly dynamic ad hoc FANETs, and it enables data communication between UAVs in various applications, such as monitoring and performing surveillance of borders, and targeted-based operations (e.g., object tracking). Vertical routing is performed over a clustered network, in which clusters are formed across different network planes to provide inter-plane and inter-cluster communications. This helps to offload data traffic across different network planes to enhance network lifetime. Compared to the traditional reinforcement learning approach, the proposed DQN-based vertical routing scheme has shown to increase network lifetime by up to 60%, reduce energy consumption by up to 20%, and reduce the rate of link breakages by up to 50%

Security and privacy issues of physical objects in the IoT: Challenges and opportunities

In the Internet of Things (IoT), security and privacy issues of physical objects are crucial to the related applications. In order to clarify the complicated security and privacy issues, the life cycle of a physical object is divided into three stages of pre-working, in-working, and post-working. On this basis, a physical object-based security architecture for the IoT is put forward. According to the security architecture, security and privacy requirements and related protecting technologies for physical objects in different working stages are analyzed in detail. Considering the development of IoT technologies, potential security and privacy challenges that IoT objects may face in the pervasive computing environment are summarized. At the same time, possible directions for dealing with these challenges are also pointed out

Pancreatic Endocrine Tumors: A Report on a Patient Treated with Sorafenib

A 31-yr-old man with abdominal pain was diagnosed with a pancreatic endocrine tumor and multiple hepatic metastases. Despite optimal treatment with interferon alpha, a somatostatin analog, local therapy with high-intensity focused ultrasound ablation for multiple hepatic metastases, and multiple lines of chemotherapy with etoposide/cisplatin combination chemotherapy and gemcitabine monotherapy, the tumor progressed. As few chemotherapeutic options were available for him, sorafenib (800 mg/day, daily) was administered as a salvage regimen. Sorafenib was continued despite two episodes of grade 3 skin toxicity; it delayed tumor progression compared to the previous immunotherapy and chemotherapy. Serial computed tomography scans showed that the primary and metastatic tumors were stable. Thirteen months after beginning targeted therapy, and up to the time of this report, the patient is well without disease progression. We suggest that sorafenib is effective against pancreatic endocrine tumors

Sensitivity of simulated summer monsoonal precipitation in Langtang Valley, Himalaya, to cloud microphysics schemes in WRF

A better understanding of regional‐scale precipitation patterns in the Himalayan region is required to increase our knowledge of the impacts of climate change on downstream water availability. This study examines the impact of four cloud microphysical schemes (Thompson, Morrison, Weather Research and Forecasting (WRF) single‐moment 5‐class, and WRF double‐moment 6‐class) on summer monsoon precipitation in the Langtang Valley in the central Nepalese Himalayas, as simulated by the WRF model at 1 km grid spacing for a 10 day period in July 2012. The model results are evaluated through a comparison with surface precipitation and radiation measurements made at two observation sites. Additional understanding is gained from a detailed examination of the microphysical characteristics simulated by each scheme, which are compared with measurements using a spaceborne radar/lidar cloud product. Also examined are the roles of large‐ and small‐scale forcings. In general, the schemes are able to capture the timing of surface precipitation better than the actual amounts in the Langtang Valley, which are predominately underestimated, with the Morrison scheme showing the best agreement with the measured values. The schemes all show a large positive bias in incoming radiation. Analysis of the radar/lidar cloud product and hydrometeors from each of the schemes suggests that “cold‐rain” processes are a key precipitation formation mechanism, which is also well represented by the Morrison scheme. As well as microphysical structure, both large‐scale and localized forcings are also important for determining surface precipitation

The Hong-Ou-Mandel effect with atoms

Controlling light at the level of individual photons has led to advances in fields ranging from quantum information and precision sensing to fundamental tests of quantum mechanics. A central development that followed the advent of single photon sources was the observation of the Hong-Ou- Mandel (HOM) effect, a novel two-photon path interference phenomenon experienced by indistinguishable photons. The effect is now a central technique in the field of quantum optics, harnessed for a variety of applications such as diagnosing single photon sources and creating probabilistic entanglement in linear quantum computing. Recently, several distinct experiments using atomic sources have realized the requisite control to observe and exploit Hong-Ou-Mandel interference of atoms. This article provides a summary of this phenomenon and discusses some of its implications for atomic systems. Transitioning from the domain of photons to atoms opens new perspectives on fundamental concepts, such as the classification of entanglement of identical particles. It aids in the design of novel probes of quantities such as entanglement entropy by combining well established tools of AMO physics - unity single-atom detection, tunable interactions, and scalability - with the Hong-Ou-Mandel interference. Furthermore, it is now possible for established protocols in the photon community, such as measurement-induced entanglement, to be employed in atomic experiments that possess deterministic single-particle production and detection. Hence, the realization of the HOM effect with atoms represents a productive union of central ideas in quantum control of atoms and photons.Comment: 19 pages, 7 figure

Expression of nicotinamide N-methyltransferase in hepatocellular carcinoma is associated with poor prognosis

<p>Abstract</p> <p>Background</p> <p>Hepatocellular carcinoma (HCC) is the most common tumor in the adult liver, with high relapse and mortality rates despite diverse treatment modalities. In this study, nicotinamide N-methyltransferase (NNMT), a key enzyme in drug metabolism, was investigated as a potential prognostic factor.</p> <p>Methods</p> <p>Frozen tumors and non-cancerous surrounding tissues from 120 patients with primary HCC were studied. Expressions of NNMT and internal control genes were measured by real-time reverse-transcription PCR (RT-PCR). The relationship of NNMT mRNA level with clinicopathologic parameters and clinical outcome was evaluated.</p> <p>Results</p> <p>NNMT mRNA level is markedly reduced in HCCs compared to non-cancerous surrounding tissues (P < 0.0001), and NNMT expression in tumors was significantly correlated with tumor stage (P = 0.010). Moreover, stratification of patients based on tumor NNMT mRNA levels revealed that the patients who expressed higher NNMT mRNA levels tended to have a shorter overall survival (OS) time (P = 0.053) and a significantly shorter disease-free survival (DFS) time (P = 0.016). Both NNMT expression (P = 0.0096) and tumor stage (P = 0.0017) were found to be significant prognostic factors for DFS in a multivariate analysis.</p> <p>Conclusion</p> <p>The results of this study indicated that NNMT gene expression is associated with tumor stage and DFS time in HCC cases. Because of the broad substrate specificity of NNMT, which could alter the efficacy and adverse effects of chemotherapy, NNMT merits further investigation regarding its role as a prognostic factor with a larger cohort of HCC patients.</p