Decisive role of fluctuations in the resource dependency networks

Individual components of many real-world complex networks produce and exchange resources among themselves. However, because the resource production in such networks is almost always stochastic, fluctuations in the production are unavoidable. In this paper, we study the effect of fluctuations on the resource dependencies in complex networks. To this end, we consider a modification of a threshold model of resource dependencies in networks that was recently proposed, where each vertex can either be in a fit or a degraded state. We study how the "network fitness" is affected as the fluctuation size is varied. We show that, the relative value of the average production with respect to the threshold, decides whether the fluctuations are beneficial or detrimental to the network fitness. We further show that the networks with a homogeneous degree distribution, such as the Erdos-Renyi network, perform better in terms of fitness and also produce lower wastage than the Scale-Free network. Our work shows that, in the study of resource dependencies in networks, the role of the fluctuations is as decisive as the average production.Comment: 9 pages, 7 figure

Climate changes instead of global warming

Air temperature changes on Earth in recent years are the subject of numerous and increasingly interdisciplinary research. In contrast to, conditionally speaking, generally accepted views that these changes are conditioned primarily by anthropogenic activity, more results appear to suggest that it is dominant natural processes about. Whether because of the proven existence of areas in which downtrends are registered or the stagnation of air temperature, as opposed to areas where the increase is determined, in scientific papers, as well as the media, the increasingly present is the use of the term climate changes instead of the global warming. In this paper, we shall try to present arguments for the debate relating to the official view of the IPCC, as well as research indicating the opposite view

Leader RNA of Rinderpest virus binds specifically with cellular La protein: a possible role in virus replication

Rinderpest virus (RPV) is an important member of the Morbillivirus genus in the family Paramyxoviridae and employs a similar strategy for transcription and replication of its genome as that of other negative sense RNA viruses. Cellular proteins have earlier been shown to stimulate viral RNA synthesis by isolated nucleocapsids from purified virus or from virus-infected cells. In the present work, we show that plus sense leader RNA of RPV, transcribed from 3' end of genomic RNA, specifically interacts with cellular La protein employing gel mobility shift assay as well as UV cross-linking of leader RNA with La protein. The leader RNA synthesized in virus-infected cells was shown to interact with La protein by immunoprecipitation of leader RNA bound to La protein and detecting the leader RNA in the immunoprecipitate by Northern hybridization with labeled antisense leader RNA. Employing a minireplicon system, we demonstrate that transiently expressed La protein enhances the replication/transcription of the RPV minigenome in cells. Sub-cellular immunolocalization shows that La protein is redistributed from nucleus to the cytoplasm upon infection. Our results strongly suggest that La protein may be involved in regulation of Rinderpest virus replication

Synchronous multicentric giant cell tumor

Multicentric giant cell tumors represent less than 1% of all giant cell tumors of bones. We report a case of multicentric giant cell tumors around both the knee joints in a mentally and physically challenged adult male that resulted in rapidly progressive painful swelling, restricted mobility and, ultimately, fixed deformity. These tumors had typical radiological appearance and the diagnosis was confirmed on histopathology

Usage Pattern of Glimepiride/Metformin Fixed-dose Combination in Type 2 Diabetes Patients with CVD or at Risk of CVD: An Experience in Indian Setting

Background: Diabetes is associated with almost twofold increased risk of cardiovascular diseases (CVD). The present case-based questionnaire survey evaluated the treatment pattern and clinical experience of healthcare professionals in prescribing glimepiride/metformin fixed-dose combination (FDC) to type 2 diabetes mellitus (T2DM) patients with CVD or those patients who are at risk of CVD in the Indian settings. Material and methods: A retrospective, multicenter, observational, case-based questionnaire survey was conducted in Indian healthcare centers using medical records of patients having T2DM, with CVD or are at risk of CVD, who were prescribed any strength of glimepiride/metformin FDC. Data was collected from the patients’ medical records and was analyzed using statistical tests. Results: A total of 680 patients with T2DM with CVD or at risk of CVD were included in this study. Mean duration of diabetes in the patients was 5.7 ± 4.8 years. About 68.5% patients had hypertension, 47.9% had dyslipidemia, 25.4% had coronary artery disease (CAD), 3.6% had transient ischemic attack (TIA), 4.8% had peripheral arterial disease (PAD) and 2.9% had heart failure. Around 18.1% patients had CVD after diabetes was diagnosed, while 81.9% presented with cardiovascular (CV) issues at the time of diabetes diagnosis. All patients received glimepiride/metformin FDC as first-line therapy. About 68.2% patients on glimepiride/metformin FDC had blood pressure within optimal limits. A large proportion of patients had improvement in glycemic parameters. Weight change was noted in 18.4% of the patients overall. Of these, 59.2% had reduction in weight. There were no major adverse events and treatment efficacy and tolerability were reported as good to excellent for 94.6% and 92.9% patients, respectively. Conclusion: This case-based questionnaire survey demonstrates the usage pattern of various strengths of glimepiride/metformin FDC and the clinicians’ practice approach regarding early initiation of this combination in Indian patients with diabetes who have or are at risk of CVD

Robotic Wireless Sensor Networks

In this chapter, we present a literature survey of an emerging, cutting-edge, and multi-disciplinary field of research at the intersection of Robotics and Wireless Sensor Networks (WSN) which we refer to as Robotic Wireless Sensor Networks (RWSN). We define a RWSN as an autonomous networked multi-robot system that aims to achieve certain sensing goals while meeting and maintaining certain communication performance requirements, through cooperative control, learning and adaptation. While both of the component areas, i.e., Robotics and WSN, are very well-known and well-explored, there exist a whole set of new opportunities and research directions at the intersection of these two fields which are relatively or even completely unexplored. One such example would be the use of a set of robotic routers to set up a temporary communication path between a sender and a receiver that uses the controlled mobility to the advantage of packet routing. We find that there exist only a limited number of articles to be directly categorized as RWSN related works whereas there exist a range of articles in the robotics and the WSN literature that are also relevant to this new field of research. To connect the dots, we first identify the core problems and research trends related to RWSN such as connectivity, localization, routing, and robust flow of information. Next, we classify the existing research on RWSN as well as the relevant state-of-the-arts from robotics and WSN community according to the problems and trends identified in the first step. Lastly, we analyze what is missing in the existing literature, and identify topics that require more research attention in the future

Role of Polypyrimidine Tract Binding Protein in Mediating Internal Initiation of Translation of Interferon Regulatory Factor 2 RNA

BACKGROUND: Earlier we have reported translational control of interferon regulatory factor 2 (IRF2) by internal initiation (Dhar et al, Nucleic Acids Res, 2007). The results implied possible role of IRF2 in controlling the intricate balance of cellular gene expression under stress conditions in general. Here we have investigated the secondary structure of the Internal Ribosome Entry Site of IRF2 RNA and demonstrated the role of PTB protein in ribosome assembly to facilitate internal initiation. METHODOLOGY/PRINCIPAL FINDINGS: We have probed the putative secondary structure of the IRF2 5'UTR RNA using various enzymatic and chemical modification agents to constrain the secondary structure predicted from RNA folding algorithm Mfold. The IRES activity was found to be influenced by the interaction of trans-acting factor, polypyrimidine tract binding protein (PTB). Deletion of 25 nts from the 3'terminus of the 5'untranslated region resulted in reduced binding with PTB protein and also showed significant decrease in IRES activity compared to the wild type. We have also demonstrated putative contact points of PTB on the IRF2-5'UTR using primer extension inhibition assay. Majority of the PTB toe-prints were found to be restricted to the 3'end of the IRES. Additionally, Circular Dichroism (CD) spectra analysis suggested change in the conformation of the RNA upon PTB binding. Further, binding studies using S10 extract from HeLa cells, partially silenced for PTB gene expression, resulted in reduced binding by other trans-acting factors. Finally, we have demonstrated that addition of recombinant PTB enhances ribosome assembly on IRF2 IRES suggesting possible role of PTB in mediating internal initiation of translation of IRF2 RNA. CONCLUSION/SIGNIFICANCE: It appears that PTB binding to multiple sites within IRF2 5'UTR leads to a conformational change in the RNA that facilitate binding of other trans-acting factors to mediate internal initiation of translation

Space weather and hurricanes Irma, Jose and Katia

This research is devoted to the determination of the causal relationship between the flow of particles that are coming from the Sun and the hurricanes Irma, Jose, and Katia. To accomplish this, the lag correlation analysis was performed. High correlation coefficients confirmed a preliminary conclusion about the relationship between solar activities and the hurricane phenomenon, which allows further research. Five parameters i.e. characteristics of solar activity (10.7 cm solar radio flux (F10.7), the flows of protons and electrons with maximum energy, speed and density of solar wind particles) were chosen as model input, while the wind speed and air pressure of Irma, Jose, and Katia hurricanes were used as model output. Input data were sampled to a six hours interval in order to adapt the time interval to the observed data about hurricanes, in the period between September 28 and December 21, 2017. As a result of the preliminary analysis, using 12,274,264 linear models by parallel calculations, six of them were chosen as best. The identified lags were the basis for refinement of models with the artificial neural networks. Multilayer perceptrons with back propagation and recurrent LSTM have been chosen as commonly used artificial neural networks. Comparison of the accuracy of both linear and artificial neural networks results confirmed the adequacy of these models and made it possible to take into account the dynamics of the solar wind. Sensitivity analysis has shown that F10.7 has the greatest impact on the wind speed of the hurricanes. Despite low sensitivity of pressure to change the parameters of the solar wind, their strong fluctuations can cause a sharp decrease in pressure, and therefore the appearance of hurricanes

Observation of 1D Behavior in Si Nanowires: Toward High-Performance TFETs

This article provides experimental evidence of one-dimensional behavior of silicon (Si) nanowires (NWs) at low-temperature through both transfer (Id−VG) and capaci- tance−voltage characteristics. For the first time, operation of Si NWs in the quantum capacitance limit (QCL) is experimentally demonstrated and quantitatively analyzed. This is of relevance since working in the QCL may allow, e.g., tunneling field-effect transistors (TFETs) to achieve higher on-state currents (Ion) and larger on-/off-state current ratios (Ion/Ioff), thus addressing one of the most severe limitations of TFETs. Comparison of the experimental data with simulations finds excellent agreement using a simple capacitor model