bluuebunny/crossref_metadata_2025 huggingface dataset:
Joint CFO and DOA Estimation Using Hybrid ESPRIT and root-MUSIC Scheme for Interleaved OFDMA/SDMA Uplink
Authors: Shen Chih-Chang , Jhang Wei
Published: August 2023

This paper deals with joint carrier frequency offset (CFO) and direction of arrival (DOA) estimation for an interleaved orthogonal frequency division multiple access (OFDMA)/space division multiple access (SDMA) uplink systems that equipped with small-scale arrays. This hybrid scheme, based on the decomposition of the two-dimensional parameter finding into double one-dimensional parameter finding, uses the ESPRIT method to estimate the CFO and the root-MUSIC for the DOA estimation. Specially, for each user, after the CFO estimation from the ESPRIT method, its DOA can be obtained simultaneously via polynomial rooting. Some simulation results are presented to verify the efficiency of this hybrid scheme.
Association of Single Nucleotide Polymorphism in OCT1 and OCT3 Genes with the Efficacy of Metformin Response in North Indian Type 2 Diabetes Mellitus Patients.
Authors: Rizvi Saliha , Raza Syed Tasleem , Mahdi Farzana
Published: August 2023

Purpose
Interindividual variation in efficacy of metformin among type 2 diabetes mellitus (T2DM) patients have been associated with several genetic variants. Understanding the genetic pathways involved in pharmacodynamics of metformin can affect personalized treatment of T2DM. Our study aimed to find the implication of genetic polymorphism in organic cation transporters (OCT1 and OCT3) genes on drug efficacy of metformin therapy in T2DM patients from North India.
Methods
This study evaluated the role of OCT1 (rs628031) and OCT3 (rs2292334) polymorphism in metformin response on T2DM patients. Response to metformin was defined by HbA1c levels based on which patients (n = 177) were divided into two groups: responders (HbA1C < 7% ; n = 127) and non-responders (HbA1C ≥ 7%; n = 50). The responders were further subcategorized as T2DM patients on monotherapy (n = 55) and on combination therapy (n = 72). Genotyping was done using PCR-RFLP approach.
Results
No significant association was found between OCT1 (rs628031) polymorphism and metformin response in T2DM patients. On the other hand, significant association of OCT3 (rs rs2292334) polymorphism was observed with metformin response where AA genotype carriers showed higher efficacy of metformin both in mono [OR (CI) = 0.29(0.11–0.72) and p = 0.007] and combination therapy [OR (CI) = 0.41(0.16-1.0) and p = 0.047]. Also, A allele was more prevalent in responders [OR (CI) = 0.48(0.28–0.84) and p = 0.010] while G allele was found to be associated with inefficacy of metformin in T2DM patients [OR (CI) = 2.07(1.19–3.61) and p = 0.010].
Conclusion
Genotyping of OCT3 (rs2292334) might be useful in predicting the response to metformin in T2DM patients.
Remediation of Aged Hexachlorobenzene Contaminated Soil by Nanoscale Zero-Valent Iron
Authors: Wang Qi
Published: August 2023

Currently, there are limited studies on the elimination of chlorinated organic compounds in aged soil. In this study, we utilized Nanoscale zero-valent iron (nZVI) to explore the removal of various chlorinated organic compounds presented in aged hexachlorobenzene (HCB)-contaminated soil. We also investigated the effects of initial pH values, as well as temperature, on the removal of HCB and other coexisting chlorobenzene congeners. Our results revealed that the highest removal efficiency for four chlorinated organic compounds was achieved under acidic conditions and elevated reaction temperatures. The maximum removal efficiency was higher than 80% for HCB and reached 90%, 60%, and 30% for pentachlorobenzene (PeCB), 1,2,4,5-tetrachlorobenzene (1,2,4,5-TeCB), and 1,2,4-trichlorobenzene (1,2,4-TCB), respectively. The removal of HCB by nZVI followed pseudo-first-order kinetics, which was different to other chemicals selected in this study. The reaction rate constant varied from 0.27 (initial pH value of 3) to 0.021 (initial pH value of 11). Furthermore, the reaction temperature was another affecting factor of the rate constant, which increased from 0.036 (15°C) to 0.192 (45°C). Notably, the presence of H+ did not significantly influence the rate-determining step of the chemical dehalogenation process for HCB and coexisting chlorobenzene congeners throughout the entire reaction. The removal of HCB and PeCB using nZVI in aged HCB-contaminated soil was characterized as an endothermic and diffusion-controlled process, with activation energies of 38.02 kJ/mol and 17.34 kJ/mol, respectively.
Analysis of pulse wave propagation characteristics in abdominal aortic sclerosis disease
Authors: Miao Fuxing , Sun Xuehang , Li Bensen , Lu Yicheng , Chen Xiabo
Published: August 2023

In this paper, a bidirectional fluid‒solid coupling finite element analysis model of the abdominal aorta was established with the use of vascular elastic modulus as the main indicator of atherosclerosis, in consideration of blood dynamic viscosity and compressibility, and pulse-wave propagation time-course calculations were carried out by the application of full-coupling analysis of the arbitrary Lagrangian‒Eulerian algorithm in COMSOL Multiphysics. The effect of atherosclerosis degree on the propagation characteristics of pulse waves in the bifurcated abdominal aorta was quantitatively analyzed. An increase in the modulus of elasticity of the arterial wall resulted in a considerable decrease in the peak pressure pulse wave, an increase in the pressure wave velocity, and a decrease in the axial wave velocity. Arterial bifurcation caused a substantial attenuation of the peak pressure pulse wave and an increase in wave velocity during the cardiac cycle. The modulus of elasticity and bifurcation properties of the arterial wall directly affected the peak value and wave velocity in the propagation of the pressure pulse wave. In addition, the stress concentration effect was evident at the bifurcation site, which was prone to the occurrence of lesions, such as arterial lumen stenosis, and the formation of arterial plaques. In conclusion, in atherosclerotic disease, the time course of pulse-wave propagation changes due to alterations in the geometry and material properties of the vessel wall. The preliminary results of this research will be crucial in guiding the evolution of the pressure pulse wave and the initial diagnosis of atherosclerotic disease through its waveform.
Comparative Survival Analysis Between Pathological N3B Nodal Disease and Other Node Positive Patients of Oral Squamous Cell Carcinoma and Their Management in Current Practice - Single Centre Experience.
Authors: ARORA VIKAS , YADAV VISHAL , Mandal Ghanashyam , Dewan Krati , Chakraborty Arnab , Sharma Prerit , Pasricha Sunil , Dewan Ajay Kumar
Published: August 2023

Background
Regional nodal metastasis with extra nodal extension (ENE) in patients of oral cavity squamous cell carcinoma (OCSCC) has a low survival in spite of aggressive multimodality therapeutic approach. Till now there is no level I data for decision making, and optimal treatment for N3b nodal disease. We aim at providing our institutional experience on survival analysis of N3b nodal disease in OCSCC, including its pattern on loco regional & distant recurrence.
Methods
Retrospective analysis of all diagnosed nodal positive 199 patients (from January 2019 to December 2020 ) of OCSCC was done. These patients underwent surgery followed by adjuvant therapy & were followed up for atleast 2 years.
Results
199 patients underwent surgery. 89 (44.7%) patients had pN3b disease & 110 patients (55.3%) had non-N3b disease (N1 to N3a). 2-year overall survival for pN3b & non N3b was 58.2% & 97.1% (P = 0.0023). Most common sites of distant metastasis were lung, bone, liver. 33 (37.1%) patients from N3b cohort and 20 (18.2%) patients from non N3b cohort had recurrence within 2 years. Interestingly, patients in N3b cohort, commonly had loco regional recurrence (primary site > neck node > satellite nodules).
Conclusions
OCSCC with N3b nodes is an aggressive subtype with poor prognosis in spite of R0 resection and adjuvant therapy. Maintenance with Metronomic / Immunotherapy at least for initial 2 years should be considered. There is a pressing need to identify N3b status on pre-operative radiology & consider neoadjuvant immunotherapy +/- CT.
Single-cell RNA sequencing reveals the cellular and molecular heterogeneity of treatment-naïve primary osteosarcoma in dogs
Authors: Ammons Dylan , Hopkins Leone , Cronise Kathryn , Kurihara Jade , Regan Daniel , Dow Steven
Published: August 2023

Osteosarcoma (OS) is a heterogeneous, aggressive malignancy of the bone that disproportionally affects children and adolescents. Therapeutic interventions for OS are limited, which is in part due to the complex tumor microenvironment (TME) that has proven to be refractory to immunotherapies. Thus, there is a need to better define the complexity of the OS TME. To address this need, we used single-cell RNA sequencing (scRNA-seq) to describe the cellular and molecular composition of the TME in 6 treatment-naïve dogs with spontaneously occurring primary OS. Through analysis of 35,310 cells, we identified 30 distinct immune cell types, 9 unique tumor populations, 1 cluster of fibroblasts, and 1 cluster of endothelial cells. Independent reclustering of major cell types revealed the presence of follicular helper T cells, mature regulatory dendritic cells (mregDCs), and 8 transcriptomically distinct macrophage/monocyte populations. Cell-cell interaction inference analysis predicted that mregDCs and tumor-associated macrophages (TAMs) play key roles in modulating T cell mediate immunity. Furthermore, we used publicly available human OS scRNA-seq data to complete a cross-species cell type gene signature homology analysis. The analysis revealed a high degree of cell type gene signature homology between species, suggesting the cellular composition of OS is largely conserved between humans and dogs. Our findings provide key new insights into the biology of canine OS and highlight the conserved features of OS across species. Generally, the data presented here acts as a cellular and molecular roadmap of canine OS which can be applied to advance the translational immuno-oncology research field.
Determination of space-time-dependent source terms in the integer-fractional MIM solute transport model based on dynamical system
Authors: Yu Chengyuan , Liu Wenyi , Li Gongsheng
Published: August 2023

We consider a numerical inversion problem of determining two space-time-dependent source terms in the integer-fractional MIM solute transport model by using the Dirichlet-Neumann boundary data. The unique existence of a solution to the forward problem is obtained by the inverse Laplace transform, and a dynamical system connecting the known data with the unknown sources is established by the variational method and boundary homogenization. The dynamical system is discretized to a linear system at given time in the homogenized polynomial space, and the source functions can be reconstructed by the alternative iteration and Tikhonov regularization. Two examples are presented to illustrate the validness of the inversion algorithm.
MSC(2010) 35R11; 35R30; 65N21
M2AST:MLP-Mixer-based Adaptive Spatial-Temporal Graph Learning for Human Motion Prediction
Authors: Tang Junyi , Liu Yuanwei , Su Yong , An Simin
Published: August 2023

Human motion prediction is a challenging task in human-centric computer vision that involves forecasting future poses based on historical sequences. Despite recent progress in modeling spatial-temporal relationships of motion sequences using complex structured graphs, few approaches have been able to provide an adaptive and compact representation for varying graph structures of human motion. Inspired by the advantages of MLP-Mixer, a lightweight architecture developed for learning complex interactions in multi-dimensional data, we explore its potential as a backbone for motion prediction. Human motion prediction is a challenging task in human-centric computer vision, involving forecasting future poses based on historical sequences. Despite recent progress in modeling spatial-temporal relationships of motion sequences using complex structured graphs, few approaches have provided an adaptive and lightweight representation for varying graph structures of human motion. Taking inspiration from the advantages of MLP-Mixer, a lightweight architecture designed for learning complex interactions in multi-dimensional data, we explore its potential as a backbone for motion prediction. To this end, we propose a novel MLP-Mixer-based adaptive spatial-temporal pattern learning framework (M\(^2\)AST). Our framework includes an adaptive spatial mixer to model the spatial relationships between joints, an adaptive temporal mixer to learn temporal smoothness, and a local dynamic mixer to capture fine-grained cross-dependencies between joints of adjacent poses. The final method achieves a compact representation of human motion dynamics by adaptively considering spatial-temporal dependencies from coarse to fine. Unlike the trivial spatial-temporal MLP-Mixer, our proposed approach can more effectively capture both local and global spatial-temporal relationships simultaneously. We extensively evaluated our proposed framework on three commonly used benchmarks (Human3.6M, AMASS, 3DPW MoCap), demonstrating comparable or better performance than existing state-of-the-art methods in both short and long-term predictions, despite having significantly fewer parameters. Overall, our proposed framework provides a novel and efficient solution for human motion prediction with adaptive graph learning.
The Relationship Between Temperatures, Electricity Consumption, and Business Cycles in Mexico
Authors: German-Soto Vicente , Favela Ruth A. Bordallo
Published: August 2023

This research uses the X-13 ARIMA methodology to investigate the co-movement, persistence, and volatility of business cycles, electricity consumption, and temperatures in Mexico during the period 2003.I–2019.IV. Theoretically, electricity consumption sustains a direct but non-linear relationship with economic development and temperatures because it is affected by seasonal factors. The greater the volume of economic activity, the greater the demand for electrical energy. Furthermore, extreme weather increases demand for electricity. During extreme weather seasons, electricity consumption is accentuated due to the greater fluctuation in the electricity supply. Our study finds that electricity consumption is procyclical––with regard to the business cycle––but maximum and minimum temperatures are countercyclical. Meanwhile, the link between minimum temperature and business cycle shows the greatest volatility, indicating that extreme cold represents a more significant risk factor than extreme heat. Furthermore, the duration of fluctuations is not significant, a result explained by the seasonality of the temperature. These findings enable the conclusion that temperatures have substantial effects on economic development and electricity supply. This leads to some policy recommendations that might address future electricity demand.
Application of nitrogen-doped reduced graphene oxide-persimmon tannin nanocomposites for electrochemical detection of Cd (II) in water resources
Authors: Zhang Shuai
Published: August 2023

A ultrasensitive electrochemical biosensor was successfully constructed for the detection of Cd (II) based on nitrogen-doped reduced graphene oxide-persimmon tannin (PT-N-RGO) and gold nanoparticles (Au NPs) modified screen printing electrode (SPE). The structure and morphology of the prepared PT-N-RGO nanocomposite were characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (TEM). And each step in the sensor preparation was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Au NPs as a material of modified electrode not only increased the effective surface area of the electrode, but also promoted the electron transfer during the redox reaction. The high specific surface area of PT-N-RGO composites further increased the electron transfer rate, thus improving the conductivity of the electrode and providing more binding sites for the subsequent capture of Cd (II). Under the optimized experimental conditions, the sensor exhibited good linearity in the range of 3.0~30 µg/L Cd (II) with a minimum detection limit of 0.46 µg/L. The sensor showed good selectivity, stability and reproducibility for the determination of Cd (II). The sensor was applied to the analysis of real water samples and the results were verified by inductively coupled plasma mass spectrometry (ICP-MS), and satisfactory results were obtained, providing a new idea for the effective determination of trace heavy metals in the environment.
Flight Traits of Dengue-Infected Aedes Aegypti Mosquitoes
Authors: Javed Nouman , López-Denman Adam J. , Paradkar Prasad N. , Bhatti Asim
Published: August 2023

Understanding the flight behaviour of dengue-infected mosquitoes can play a vital role in various contexts, including modelling disease risks and developing effective interventions against dengue. Studies on the locomotor activity of dengue-infected mosquitoes have often faced challenges in terms of methodology. Some studies used small tubes, which impacted the natural movement of the mosquitoes, while others that used cages did not capture the three-dimensional flights, despite mosquitoes naturally flying in three dimensions. Here we performed a comprehensive analysis of the three-dimensional flight behaviour of dengue-infected Aedes aegypti mosquitoes using Mask RCNN (Region-based Convolutional Neural Network). This analysis considered varying parameters such as flight duration, number of flights, Euclidean distance, flight speed, and the volume (space) covered during flights. Results revealed that dengue infection significantly increases the flight duration and volume (space) covered during flights whilst decreasing the total number of flights compared to uninfected mosquitoes. The study did not observe any evident impact on the Euclidean distance and speed of Aedes aegypti. These results highlight the intricate relationship between dengue infection and the flight behaviour of Aedes aegypti, providing valuable insights into the virus transmission dynamics.
Massive superfluid vortices and vortex necklaces on a planar annulus
Authors: Caldara Matteo , Richaud Andrea , Capone Massimo , Massignan Pietro
Published: August 2023

We study a superfluid in a planar annulus hosting vortices with massive cores. An analytical point-vortex model shows that the massive vortices may perform radial oscillations on top of the usual uniform precession of their massless counterpart. Beyond a critical vortex mass, this oscillatory motion becomes unstable and the vortices are driven towards one of the edges. The analogy with the motion of a charged particle in a static electromagnetic field leads to the development of a plasma orbit theory that provides a description of the trajectories which remains accurate even beyond the regime of small radial oscillations. These results are confirmed by the numerical solution of coupled two-component Gross-Pitaevskii equations. The analysis is then extended to a necklace of vortices symmetrically arranged within the annulus.
O complexo regional de segurança da América do Sul
Authors: Albergaria de Queiroz Fábio , Villamil Balestro Moisés
Published: August 2023

Complexos Regionais de Segurança (CRS) são construções sociais derivadas de relações de interdependência estabelecidas a partir de interações entre variáveis materiais e ideacionais. Contudo, tal qual outras leituras de natureza conjuntural, a Teoria dos Complexos Regionais de Segurança (TCRS) demanda esforço contínuo de atualização. Dito isso, passadas quase duas décadas desde a apresentação de sua versão mais desenvolvida (2003) e, considerando, neste período, dinâmicas multissetoriais que atuaram na conformação da agenda regional de segurança, seria um contexto de geometria variável de poder capaz de impactar a natureza estrutural do CRS da América do Sul? Para tanto, entre 2006 e 2020, avaliamos elementos que permitiram testar a hipótese de que a América do Sul seria o primeiro caso empírico de uma nova categoria de CRS, utilizando como metodologia o estudo de caso comparativo diacrônico. Concluímos que esse CRS não teria transposto, até o momento, quanto à polaridade, sua epistemologia original.
Interagency operations in analysis learning from episodes in Caraguatatuba, Goiânia and Rio de Janeiro
Authors: Abreu de Figueiredo Thiago , Xavier Moreira Nádia , Machado Caminha Viviane
Published: August 2023

This paper addresses the learning process related to the development of interagency operation and its doctrine resulted from three episodes’ analysis: the hecatomb in Caraguatatuba, the radiologic accident with cesium-137 in Goiania, and the disaster at the mountainous region in Rio de Janeiro. The literature review and documental analysis carried out in this work intend to obtain teachings and to shed light on a time gap previous from the 1st edition of the “Interagency Operations” Manual (BRASIL, 2012a), published by Defense Ministry in 2012. The results from this study points out problems that hampered the effectiveness regarding the mobilization of civil and military institutions in order to resolve the complex matters faced at the time of the episodes. Thus, we conclude the necessity of qualification regarding a better practice of interagency that can be enabled by means of courses and trainings, in which the future paths of these operations can be addressed, considering not advisable the reunion of agencies exclusively during crisis moments.
Production and Characterization of Bioactive and Antimicrobial Titanium Oxide Surfaces with Silver Nanoparticles and a Poly(lactic Acid) Microfiber Coating
Authors: Zaniolo Karina , Biaggio Sonia , Cirelli Joni , Cominotte Mariana , Bocchi Nerilso , Rocha-Filho Romeu , de Souza Clovis
Published: August 2023

Silver nanoparticles (AgNp) were deposited on highly porous TiO2 surfaces by the dripping of a colloidal AgNp solution to provide antimicrobial activity. Micro-porous TiO2 surfaces were obtained on commercially pure titanium by micro-arc oxidation in an electrolyte containing Ca and P precursors. In addition, as silver can be toxic to cells, these surfaces were uniformly covered with the biocompatible and bioresorbable poly(lactic acid) (PLA) polymer by electrospinning, aiming at promoting a controlled release of silver ions to the medium. The resulting AgNp-containing surfaces were characterized by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD), and in vitro assays were performed to evaluate their antimicrobial activity and bioactivity. Tests revealed that the surfaces showed antimicrobial activity against Staphylococcus aureus, with better results for the surfaces without PLA. However, all the surfaces presented good biocompatibility in assays with mouse MC3T3-E1 pre-osteoblasts, and greater cell differentiation for the polymer-coated surfaces. Finally, the PLA ultrafine fibers electrospun on the TiO2/AgNp surfaces allowed a controlled release of silver ions in the phosphate-buffered saline (PBS) medium.
Moving to ambidextrous organization: A systematic literature review
Authors:   St. Petersburg State University, Smara Rafik , Bogatyreva Karina A. ,   St. Petersburg State University
Published: August 2023

The existing studies support the positive impact of organizational ambidexterity on a firm’s performance and its ability to succeed in the dynamic environments resulted from the COVID-19 pandemics or contexts characterized by a variety of rising tensions. In business organizations, ambidexterity manifests itself in maintaining a balance between exploration and exploitation strategies. Achieving ambidexterity is a challenging managerial task. The purpose of this paper is to identify behaviours of firms to increase their ability to develop and maintain ambidexterity as well as specify organizational systems and processes that induce and balance both exploitation and exploration. The authors develop an integrative framework that provides a comprehensive understanding of the path towards ambidexterity in organizations. This review reveals the fact that with the purpose to meet the conflicting demands of the ambidexterity agenda, managers should adapt the organizational culture, strategic goals and structure in order to implement two incompatible innovation strategies. The study identifies three closely related ambidexterity support systems and their underlying mechanisms, procedures, and leadership styles. Also, the main gaps in the literature and relevant directions for further empirical research are outlined. Keywords: ambidexterity, balance, exploration, exploitation.
Plot features of the travelogue My Son on the Galley by J. Wallenberg
Authors: Morozov Artem
Published: August 2023

The paper deals with the specific plot features of a popular Swedish travelogue My Son on the Galley (1781) in which Jacob Wallenberg describes his journey from Sweden to China in 1769–1771. The object of analysis is the general plot structure in travel novels (using Mikhail Bakhtin’s terminology) and travelogues. As a result, it is proved that My Son on the Galley is a travelogue with a linear, chronological plot structure. It includes not only description of the itself and documentary information (about the geographical and demographic position of the countries visited by the narrator, descriptions of local nature, traditions, etc.), but also there are adventurous episodes (for example, about old maids, frightened by the appearance of the Swedes; about the ship, which the sailors mistook for a pirate one, etc.) in the text. Digressions from the main theme — the journey — are interspersing as colorful illustrations of the thoughts of the narrator, and as natural-geographical, ethnographic, cultural content etc. which are so typical for travelogues, although they do not play significant role in this book. The main object for the narrator is not visit to one country or another, but secondary details of the surrounding reality, as well as author’s thoughts inspired by the journey. There are also chapters that deal with things that are not directly related to the journey (for example, domestic violence and infidelity of wives). The travelogue My Son on the Galley stands at the origins of Swedish sentimentalist prose, which was developed at the end of the 18th century.
Self-adaptive metaheuristic optimization technique for multi-objective reservoir operation
Authors: Kumar Vijendra , Sharma Kul Vaibhav , Yadav S. M , Deshmukh Arpan
Published: August 2023

Multi-objective reservoir operation presents a number of critical challenges that must be overcome for efficient management of water resources. The inherent contradiction between several goals, such as satisfying irrigation demand and maximizing hydropower generation, is one of the major issues. Trade-offs and compromises must be carefully considered to balance these objectives. To solve this problem, a study was carried out to optimize the operation of multi-objective reservoirs with two primary goals: minimizing irrigation deficits and maximizing hydropower generation. This study employs the self-adaptive multipopulation multi-objective Jaya algorithm (SAMP-MOJA), an improved version of the Jaya algorithm, to construct an optimal Pareto Front utilizing an a priori approach. The performance of SAMP-MOJA is compared to that of other algorithms such as multi-objective particle swarm optimization, multi-objective invasive weed optimization, and multi-objective Jaya algorithm. The results of this study demonstrate that the hydropower generated by the developed model surpasses 80% of the actual generation. The study's findings will aid in designing the most effective Pareto front possible.
Geospatial mitigation of the effect of undulating terrain on efficient water distribution network: a case study of Enugu Urban, South-Eastern Nigeria
Authors: Ugwuoti Amos Iloabuchi , Ojinnaka Oliver Chinagorom , Ibem Eziyi Ofia , Uzodinma Victus Ndubisi
Published: August 2023

Undulating terrain has continued to aggravate pipe-borne water supply challenges in the Enugu Urban area. The rapid increase in urbanization has worsened the situation. This, therefore, calls for the deployment of systems that can support the effective planning of surface and underground facilities for the development of an efficient water distribution network in this region. Remote Sensing, Geographic Information Systems (GIS), Hydrographic Survey, and Geophysical Survey, collectively referred to as geospatial technologies, have been combined in different ways by developed nations to resolve challenges facing surface and underground facilities. This study, therefore, demonstrates the application of this technology in designing an efficient water distribution network for urban areas with undulating terrain. The spot heights dataset extracted from Light Detection and Ranging (LiDAR) satellite imagery offered the bases for the re-structure of the existing water distribution network map to accommodate the undulation of the topography. This was integrated into a GIS tool to synergize the topography with the radial and dead-end standard water distribution patterns. The result was a sub-division of the Enugu Urban Area into 12 zones with reservoirs at the most elevated points to facilitate water reticulation by gravity. The efficacy of this distribution network map was confirmed suitable with EPANET software.
A case study of comparative techno-economic and life cycle assessment of tap water versus household reverse osmosis-based drinking water systems in a North Indian city
Authors: Gani Khalid Muzamil , Rather Sohaib Rashid , Chandra Amit , Arshid Mubashir
Published: August 2023

Household reverse osmosis (RO)-based water purifiers have gained popularity in India due to concerns about the quality of tap water. However, the widespread adoption of these systems has significant impacts on water pricing and the environment. The objective of this study was to assess the techno-economic performance and life cycle assessment (LCA) of household RO-based water purifiers in Srinagar city of North India. Our results demonstrate that household ROs reduce the concentration of important dietary minerals such as fluoride and magnesium in drinking water by 50%. In addition, the average total water cost from a household RO is three to four times more than what is being paid for tap water. Two different scenarios were compared in LCA. The first scenario was safe drinking water from a conventional drinking water treatment plant (scenario 1), while the second scenario was water from a household RO system (scenario 2). The results showed that the environmental impacts of abiotic depletion, acidification of water bodies, eutrophication, global warming and ozone depletion in scenario 2 were higher than in scenario 1. The findings infer that water utilities should encourage citizens to rely on conventional tap water as a cheaper and environmentally friendly option compared to household ROs.
Restauración monumental en Lima en el período 1920-1990
Authors: Hayakawa Casas José Carlos
Published: August 2023

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Solution synthesis of monodispersed nanocrystalline FCC-, e- and HCP-Cobalt particles
Authors: Perales Oscar , Jeyadevan Balachadran , Tohji Kazuyuki , Kasuya Atsuo
Published: August 2023

The systematic research of the "polyol process" applied to the production of metallic Cobalt particles is presented. In this approach, the control of the reaction kinetics and the metal particla size were achieved through a suitable selection of the solution chemistery in the ethylene glycol (EG)- or Trimethylene glycol (TMEG)-Cobalt (II) system. The adition of hydroxil ions into the Co solution in EG caused a dramatic shorteninig of the reaction time. This sortening in reaction time permited a convenient control of the size of sub-micron Co particles in reaction time with a highmonodispersity. A further tailoring of the particle size was achieved by using acetate iones. Under the latter condition, monodispersed Co particles of about 220-nm in diameter were produced. The Co particles were polycristalline and their structure consisted of either fcc or fcc/hcp mixtures. The saturation magnetization (Ms) and coercivity (Hc) at room temperature ranged from 65 to 162 emu/g and 35 to 199 Oe, respectively. In presence of Pt ions, Cobalt nanoparticles as small as 25 nm were synthesized. Depending on syntehsis conditions, metastable e-Co and/or hcp-Co were stabilized at the nanosize livel. The high coercivity-hcp phase was produced without need of the annealing. The Ms and HC of the Co particles synthetized in presence of Pt ions, varied from 53 to 77 emu/g and 222 to 535 Oe, respectively.
Invernaderos con cultivos rentables
Authors: Del Carpio Salinas Jorge Alberto , Huamán Bustamante Samuel Gustavo , Closter Orellana Gabriel
Published: August 2023

El proyecto consistió en el diseño y construcción de un sistema de cultivo hidropónico para evaluar el sistema de control de temperatura, humedad, riego y luminosidad en un invernadero de 50 m2. Se cultivo tomates y lechugas, Integrado a un cultivo de hongos comestibles "champiñones" durante los meses de diciembre a febrero. Los cultivos hidropónicos fueron alimentados a través de riego por goteo. Ambos cultivos fueron regados independientemente en uno del otro según el plan de riego programado. Las altas temperaturas registradas al interior del invernadero durante el día afectaron el adecuado crecimiento y productividad de los cultivos, además desbordaron el equipo de control de medio ambiente. Se diseño y construyó una estación meteorológica que estuvo disponible al final del proyecto y fue una mejora del primer prototipo. Todos los equipos se conectaron en una red RS485, que está configurada para enviar valores digitales a un computador personal con una interfase de usuario para almacenar y administrar una base de datos en MYSQL.
Diseño, construcción y procesamiento de señales de un acelerógrafo para la red de acelerógrafos del CISMID
Authors: Del Carpio Salinas Jorge Alberto , Calderón Morocho Félix Martín , Román Quispe Percy Kike
Published: August 2023

Nuestra ubicación en el mundo nos hace ser un país con un alto riesgo sísmico. Teniendo en cuenta que la información producida durante un evento sísmico es de vital importancia para el estudio que realiza la sismología se hace una necesidad utilizar el tipo de instrumentación adecuada para el registro de estos datos. En la actualidad la electrónica aporta la tecnología necesaria para el estudio de fenómenos de este tipo. El diseño y construcción de un Acelerógrafo Digital nos permitirá el estudio detallado de un movimiento sísmico y el efecto causado sobre la estructura de las edificaciones. Podemos, finalmente, decir que la construcción de un instrumento de este tipo a un bajo costo permitirá repotenciar y aumentar la red acelerógrafica del CISMID y en general mejorar el conocimiento que se tiene a nivel nacional de los fenómenos sísmicos.
Configuraciones óptimas de aglomerados y dependencia con respecto a la deformación de las energías de activación sobre superficies Cu(001)
Authors: Coronado Matutti Alberto
Published: August 2023

Uno de los aspectos más importantes en el crecimiento epitaxial de peliculas finas es la movilidad de adatoms y pequeños aglomerados. Como esta movilidad está relacionada a las energías de activación, muchos estudios están concentrados en el cálculo y determinación del rol de estas energías. Por ejemplo, estudios previos mostraron que las energías de activación pueden ser fácilmente modificadas, usando campos de deformación. No obstante muchos aspectos aún no están muy claros. En este trabajo empleamos Algoritmos Genéticos para calcular configuraciones óptimas de agregados sobre superficies Cu(001) modeladas con el método de los átomos embebidos (EAM). Las configuraciones óptimas obtenidas no mostraron dependencia con respecto a la deformación aplicada. Adicionalmente estudiamos la dependencia de las energías de activación de salto e intercambio con respecto al nivel de deformación aplicada. Se observó que el salto muestra una dependencia clara con respecto a la tensión o compresión biaxial, en contraste al intercambio, cuya dependencia es más compleja.
Análisis modal de la hélice terminal C de la subunidad gamma en la enzima ATP
Authors: Saavedra Espinoza Harry Gustavo , Coronado Matutti Alberto
Published: August 2023

En el análisis dinámico de proteinas, un objetivo importante es la descripción de los movimientos lentos de grandes amplitudes. Estos movimientos describen configuraciones de reordenamiento que son importantes para la función de la proteina. Estos reordenamientos pueden cambiar la superficie de exposición de la proteína, y por lo tanto, influenciar las interacciones con su entorno. En este artículo, estudiamos los modos de baja frecuencia de la hélice Terminal C de la ATP Sintasa de la subunidad Gamma. Tres métodos son comparados: Modos Browinanos, Modos Calpha y Modos de Potencial Simplificado. Los resultados sugieren que el extremo F, de la hélice es más rigido que otras partes. Esto es coherente con los recientes estudios donde se muestra como el extremo F, de la hélice trabaja como un eje cigueñal convirtiendo el movimiento de doblado y desdoblado de la subunidad Beta en movimiento rotacional. Además, a lo largo de la hélice, longitudes flexibles son seguidas de longitudes rígidas. Esta propiedad puede servir para suavizar el torque producido en el extremo de F, entregando un torque casi constante que es necesario para alcanzar la más alta eficiencia posible.
Dosimetría para campos pequeños de electrones de alta energía utilizando películas radiográficas
Authors: Bernui de Vivanco Ma Giselle , Morales Landín Maria Elena , Cárdenas Retuerto Augusto
Published: August 2023

En nuestra institución hay una considerable cantidad de pacientes con carcinomas de piel, para los cuales, el tratamiento de radioterapia con campos pequeños de electrones de alta energía es una de las opciones más comunes de tratamiento. La dosimetría mediante cámara de ionización en campos pequeños de electrones de alta energía, según lo especifican los protocolos internacionales de dosimetría, requiere de cámaras de ionización con características especiales; equipos con los que no contamos en nuestra institución. Esto nos pone en la necesidad de utilizar un método alternativo para realizar estas mediciones. El comportamiento lineal de las películas en electrones de energías mayores a los 250 keV, hacen de la dosimetría de pelicula una de las mejores opciones para realizar mediciones en campos pequeños de electrones de alta energía; tanto por su calidad de resultados, información que se dispone y bajo costo. Este trabajo tiene como objetivo proveer al departamento de radioterapia del Instituto Nacional de Enfermedades Neoplasicas de un método práctico, seguro y económico para realizar la dosimetría de campos pequeños de electrones de alta energía; de tal manera que los recomendaciones internacionales para dosimetría de electrones de alta energia utilizando película, sean aplicados teniendo en cuenta los recursos que disponemos, sin que eso implique que la calidad de los resultados obtenidos se yea afectada en forma desfavorable.
Distanciómetro de triangulación láser
Authors: Mosquera L. Luis , Powell V. Tomas
Published: August 2023

Un telémetro láser es un dispositivo capaz de medir la distancia entre dos puntos. Un láser rojo pulsado a 1 KHz es usado como la fuente de luz, la cual impacta sobre un blanco. La luz reflejada por el blanco incide sobre un sensor óptico tipo PSD. El PSD produce dos señales de corriente que son amplificadas y filtradas. Estas señales son leídas por dos conversores análogos digitales (ADC) y son manipuladas en LabView. El programa en LabView convierte las señales provenientes del PSD en lecturas de distancias a la que se encuentra el blanco. El arreglo óptico y el tamaño del PSD determinan el rango de trabajo del telémetro, 20-80 cm en nuestro prototipo. En éste rango, la imagen del spot luminoso impactando sobre el blanco se mueve de extremo a extremo del PSD. Sobre este rango la aproximación obtenida fue de aproximadamente el 1%.
Power hybrid filter
Authors: Nuñez Z. Teresa , Moreno M. Rodolfo , Ramos C. Jorge , Soto L. Alberto
Published: August 2023

This article shows the simulation results obtained from the study of a power electronic system, which significantly improves the performance of the conventional three-phase passive filter that is normally used for power factor compensation of non-linear loads. This improvement is achieved by connecting a three-phase active (AF) filter (or active unit) in series with the passive (PF) filter through three coupling transformers and controlling the active filter in such a way as to force the harmonic components generated by the rectifier to pass through the passive filter. This topology in which a passive filter is combined with an active filter is known as Hybrid Power Filter.
Evaluación de vibraciones en estructuras usando un método óptico no convencional
Authors: Valera Aníbal , Ortiz Arturo
Published: August 2023

En este trabajo se presenta el resultado de evaluar las vibraciones de un Techo (CISMID /UNI) en base a un procedimiento no convencional, por el cual la vibración de la estructura esproducida por ondas sonoras cuasi monocromáticas y la detección de los movimientosvibratorios es medida ópticamente, por la deflexión de un rayo láser reflejado,experimentalmente se obtienen 2 frecuencias resonantes prominentes: 28.5 Hz y 45 Hz, las quese identifican como los modos resonantes (1,1) y (2.1) respectivamente.
Estudio químico de la planta medicinal "Toe" (Datura sanguínea (R.& P.) D. Don)
Authors: Reyna Pinedo Víctor , Cóndor Cuyubamba Elena
Published: August 2023

De las hojas, flores y semillas del Toe o “Misha Toro” (Datura sanguínea (R. & P.) D.Don), planta colectada en la Provincia de Huancabamba (Departamento de Piura, en la sierra norte del Perú) se aisló el alcaloide escopolamina, que fue identificado mediante sus espectros de Masas, RMN1H y RMN13C. Además, se realizó el análisis cualitativo de los metabolitos secundarios y la cuantificación de alcaloides presentes en los diferentes órganos de esta planta.
Seismic response of a five story building with isolation system and supplemental viscous dampers for peruvian seismicity
Authors: Taboada Saavedra Diego Enrique , Fernández-Dávila Víctor
Published: August 2023

Projects with seismic isolation are increasing in Peru, even the Peruvian Seismic Standard establishes that seismic isolators must be used in hospitals located in seismic zones 4 and 3 of the Peruvian seismic map. It is also accepted that there may be isolated buildings on floors S0, S1, S2 and S3.

In isolated buildings that are in soil type S3 and seismic zone 4, maximum displacement values ​​are obtained. This involves the use of flexible connections, plus in some cases these offsets result in a smaller usable area of ​​the building. An alternative to reduce these displacements is the use of supplemental viscous dampers at the base of the isolated building, which adds damping to the isolation system. In this investigation, a mathematical model of a 5-story building with elastomeric isolators, located in seismic zone 4 and soil type S3, was evaluated. This model was then analyzed with supplemental viscous dampers, considering 5 different damping percentage conditions: 15%, 30%, 45%, 60% and 75%. For all analyses, 7 time history records compatible with Peruvian seismicity were used. Isolated base displacement reductions will be acquired up to 30% of their starting value. The variation of the responses (accelerations, deviations, shear forces and dissipated energy) was analyzed as a function of the increase in damping. It was verified that the Peruvian seismic combination of isolators and dampers tends to increase the responses of the superstructure.
Nuevo modelo de desarrollo para la generación de empleos: Propuesta
Authors: Aranaga Manrique David F.
Published: August 2023

El problema del empleo en el Perú se intensifica, deteriorándose las retribuciones que perciben más del 80% de los trabajadores. Este problema se ha formado históricamente en esta sociedad, derivado de una dinámica retardada que se ha alimentado de los diferentes momentos históricos, principalmente por las deficiencias estructurales en el sistema económico nacional que han permitido que en el momento actual los trabajadores se conviertan en simple factores productivos. El Perú debe retomar el proceso de desarrollo mediante una estrategia basada en la industrialización por líneas de crecimiento que persiga entre otros objetivos la generación de empleos adecuados. Este articulo es un resumen del libro: “Deterioro y Escasa Retribución al Factor Trabajo en el Perú: 1990-1997”, publicado recientemente en esta Casa de Estudios.
Un nuevo método de desconexión de cilindros para la regulación de los motores gas-Diesel
Authors: Valderrama Romero Andrés , Patrakhaltsev Nicolai
Published: August 2023

El método de desconexión de cilindros que se propone, se fundamenta en el aprovechamiento del fenómeno hidrodinámico que se produce en la línea de alta presión de los sistemas de inyección Diesel de tipo separado; siendo de mucha utilidad en regímenes de pequeñas y medias cargas cercanas al vacío y en vacío.Opera con el sistema eléctrico de 12 ó 24 voltios, el cual envía corriente a una bobina electromagnética que acciona una válvula, levantándola, permitiendo la derivación del combustible en los cilindros que se desea desconectar; simultáneamente los cilindros que están trabajando lo hacen a plena carga y en ellos se suministra gas natural comprimido (GNC ) logrando la disminución de las emisiones tóxicas y el reemplazo del petróleo Diesel por GNC. Los ensayos experimentales se realizaron en 1994 en un motor Diesel de cuatro cilindros (S/D = 12.5/11 ), en la versión Diesel y en la versión gas-Diesel ambos en el laboratorio de la Cátedra de Motores Combinados de la Universidad Rusa de Amistad de los Pueblos, Moscú.
Extracción de carbohidratos (ácido algínico) de la especie Grateolupia Doryphora (algas pardas - Ancon - Perú)
Authors: Acha de la Cruz Otilia
Published: August 2023

De las hojas y mices de la especie Grateoloupia Doryphora fueron extraídas separadamente el manitol cristalino y dos ácidos oliguronicos, ambas extracciones se hicieron en etanol. Los "fucans" estuvieron presentes en todas las extraciones secuenciales acuosas acídicos y básicas. Cada tipo de "fucan" contenía proporciones variantes de fucosa (mayor porcentaje), galactosa, mañosa, xilosa,acido glucuronico, sulfatos y pequeñas proporciones de proteinas.Los alginatos se extrajeron directamente en medio alcalino, la diferencia de las extracciones secuenciales en ambas partes de la planta fue la mayor cantidad de ácido gulurónico presente en el acido algínico extraído en las raíces de la planta.
Combinación optima de los exámenes de admisión y vocación profesional en la FAUA-UNI
Authors: Ordoñez Mercado Alipio Francisco
Published: August 2023

En este trabajo se investiga la posibilidad de asignar pesos óptimos a los puntajes obtenidos por los postulantes a la FAUA-UNI en los exámenes de admisión y vocación profesional. Se usó un modelo lineal con restricciones y los resultados de los procesos de admisión entre 1997 y 1998. El análisis estadístico indica que las ponderaciones deben ser de 0.6 para el examen de admisión y de 0.4 para el de vocación profesional. También se detectó que el procedimiento que se usa actualmente no tiene las condiciones estadísticas para su aplicación y conduce a una mala clasificación de alrededor del 28% de los ingresantes a la FAUA.