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1.
Sci Rep ; 12(1): 13529, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35941263

RESUMO

Harmful algal blooms (HABs) are a growing concern to public health and aquatic ecosystems. Long-term water monitoring conducted by hand poses several limitations to the proper implementation of water safety plans. This work combines automatic high-frequency monitoring (AFHM) systems with machine learning (ML) techniques to build a data-driven chlorophyll-a (Chl-a) soft-sensor. Massive data for water temperature, pH, electrical conductivity (EC) and system battery were taken for three years at intervals of 15 min from two different areas of As Conchas freshwater reservoir (NW Spain). We designed a set of soft-sensors based on compact and energy efficient ML algorithms to infer Chl-a fluorescence by using low-cost input variables and to be deployed on buoys with limited battery and hardware resources. Input and output aggregations were applied in ML models to increase their inference performance. A component capable of triggering a 10 [Formula: see text]g/L Chl-a alert was also developed. The results showed that Chl-a soft-sensors could be a rapid and inexpensive tool to support manual sampling in water bodies at risk.


Assuntos
Ecossistema , Monitoramento Ambiental , Clorofila/análise , Monitoramento Ambiental/métodos , Proliferação Nociva de Algas , Aprendizado de Máquina , Água
2.
Sci Rep ; 12(1): 2091, 2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35136144

RESUMO

Due to the growing rise of cyber attacks in the Internet, the demand of accurate intrusion detection systems (IDS) to prevent these vulnerabilities is increasing. To this aim, Machine Learning (ML) components have been proposed as an efficient and effective solution. However, its applicability scope is limited by two important issues: (i) the shortage of network traffic data datasets for attack analysis, and (ii) the data privacy constraints of the data to be used. To overcome these problems, Generative Adversarial Networks (GANs) have been proposed for synthetic flow-based network traffic generation. However, due to the ill-convergence of the GAN training, none of the existing solutions can generate high-quality fully synthetic data that can totally substitute real data in the training of ML components. In contrast, they mix real with synthetic data, which acts only as data augmentation components, leading to privacy breaches as real data is used. In sharp contrast, in this work we propose a novel and deterministic way to measure the quality of the synthetic data produced by a GAN both with respect to the real data and to its performance when used for ML tasks. As a by-product, we present a heuristic that uses these metrics for selecting the best performing generator during GAN training, leading to a novel stopping criterion, which can be applied even when different types of synthetic data are to be used in the same ML task. We demonstrate the adequacy of our proposal by generating synthetic cryptomining attacks and normal traffic flow-based data using an enhanced version of a Wasserstein GAN. The results evidence that the generated synthetic network traffic can completely replace real data when training a ML-based cryptomining detector, obtaining similar performance and avoiding privacy violations, since real data is not used in the training of the ML-based detector.

4.
Transfus Apher Sci ; 60(2): 103046, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33455879

RESUMO

The recurrence of primary focal segmental glomerulosclerosis (FSGS) after kidney transplantation (KT) appears in 30 % of the recipients. Sometimes it can cause the loss of the allograft. Although many treatments for this condition have been reported, 20 %-40 % of the affected patients are refractory or presents frequents relapses. In this paper we describe the evolution of three recipients treated with long-term plasmapheresis therapy after a recurrence of FSGS with a bad or incomplete response to other treatments. Although our findings require confirmation, long-term plasmapheresis could be a therapeutic option for this condition.


Assuntos
Glomerulosclerose Segmentar e Focal/terapia , Transplante de Rim/efeitos adversos , Plasmaferese/métodos , Adulto , Feminino , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
7.
Sensors (Basel) ; 20(16)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824579

RESUMO

Internet of Things (IoT) projects are increasing in size over time, and some of them are growing to reach the whole world. Sensor arrays are deployed world-wide and their data is sent to the cloud, making use of the Internet. These huge networks can be used to improve the quality of life of the humanity by continuously monitoring many useful indicators, like the health of the users, the air quality or the population movements. Nevertheless, in this scalable context, a percentage of the sensor data readings can fail due to several reasons like sensor reliabilities, network quality of service or extreme weather conditions, among others. Moreover, sensors are not homogeneously replaced and readings from some areas can be more precise than others. In order to address this problem, in this paper we propose to use collaborative filtering techniques to predict missing readings, by making use of the whole set of collected data from the IoT network. State of the art recommender systems methods have been chosen to accomplish this task, and two real sensor array datasets and a synthetic dataset have been used to test this idea. Experiments have been carried out varying the percentage of failed sensors. Results show a good level of prediction accuracy which, as expected, decreases as the failure rate increases. Results also point out a failure rate threshold below which is better to make use of memory-based approaches, and above which is better to choose model-based methods.

8.
Nefrología (Madrid) ; 40(3): 272-278, mayo-jun. 2020. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-187525

RESUMO

La reciente aparición de la pandemia por el coronavirus SARS-CoV-2 ha impactado de forma muy importante en la población general. Los pacientes en tratamiento renal sustitutivo (TRS) no han sido ajenos a esta situación y por sus características resultan especialmente vulnerables. Presentamos los resultados del análisis del Registro COVID-19 de la S.E.N. MATERIAL Y MÉTODOS: EL Registro comenzó a funcionar el 18 de marzo de 2020. Recoge variables epidemiológicas, datos del contagio y diagnóstico, clínica acompañante, tratamientos y desenlace. Se trata de un registro "on line". Los pacientes fueron diagnosticados de infección por SARS-Cov-2 en base a los resultados de la PCR del virus, realizada tanto en pacientes que habían manifestado clínica compatible o tenían signos sospechosos como en aquellos a los que se había hecho como cribado tras algún contacto conocido con otro enfermo. RESULTADOS: A fecha 11 de abril el Registro disponía de datos de 868 pacientes, procedentes de todas las Comunidades Autónomas. La modalidad de TRS más representada es la hemodiálisis en centro (HDC) seguida de los pacientes trasplantados. La clínica de presentación es similar a la población general. Un porcentaje muy elevado (85%) requirió ingreso hospitalario, un 8% en unidades de cuidados intensivos. Los tratamientos más utilizados fueron hidroxicloroquina, lopinavirritonavir y esteroides. La mortalidad es elevada y alcanza el 23%: los pacientes fallecidos estaban con más frecuencia en HDC, desarrollaban más frecuentemente neumonía y recibían en menos ocasiones lopinavir-ritonavir y esteroides. La edad y la neumonía se asociaban de forma independiente al riesgo de fallecer. CONCLUSIONES: La infección por SARS-CoV-2 afecta ya a un número importante de pacientes españoles en TRS, fundamentalmente aquellos que están en HDC, las tasas de hospitalización son muy elevadas y la mortalidad es elevada; la edad y el desarrollo de neumonía son factores asociados a mortalidad


The recent appearance of the SARS-CoV-2 coronavirus pandemic has had a significant impact on the general population. Patients on renal replacement therapy (RRT) have not been unaware of this situation and due to their characteristics they are especially vulnerable. We present the results of the analysis of the COVID-19 Registry of the Spanish Society of Nephrology. MATERIAL AND METHODS: The Registry began operating on March 18th, 2020. It collects epidemiological variables, contagion and diagnosis data, signs and symptoms, treatments and outcomes. It is an "online" registry. Patients were diagnosed with SARS-Cov-2 infection based on the results of the PCR of the virus, carried out both in patients who had manifested compatible symptoms or had suspicious signs, as well as in those who had undergone screening after some contac, acquainted with another patient. RESULTS: As of April 11, the Registry had data on 868 patients, from all the Autonomous Communities. The most represented form of TRS is in-center hemodialysis (ICH) followed by transplant patients. Symptoms are similar to the general population. A very high percentage (85%) required hospital admission, 8% in intensive care units. The most used treatments were hydroxychloroquine, lopinavir-ritonavir, and steroids. Mortality is high and reaches 23%; deceased patients were more frequently on ICH, developed pneumonia more frequently, and received less frequently lopinavir-ritonavir and steroids. Age and pneumonia were independently associated with the risk of death. CONCLUSIONS: SARS-CoV-2 infection already affects a significant number of Spanish patients on RRT, mainly those on ICH, hospitalization rates are very high and mortality is high; age and the development of pneumonia are factors associated with mortality


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Infecções por Coronavirus/mortalidade , Pneumonia Viral/mortalidade , Betacoronavirus , Pandemias , Diálise Renal/mortalidade , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/virologia , Transplante de Rim/efeitos adversos , Unidades Hospitalares de Hemodiálise/estatística & dados numéricos , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Espanha/epidemiologia , Fatores de Risco
9.
Nefrologia (Engl Ed) ; 40(3): 272-278, 2020.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32389518

RESUMO

INTRODUCTION: The recent appearance of the SARS-CoV-2 coronavirus pandemic has had a significant impact on the general population. Patients on renal replacement therapy (RRT) have not been unaware of this situation and due to their characteristics they are especially vulnerable. We present the results of the analysis of the COVID-19 Registry of the Spanish Society of Nephrology. MATERIAL AND METHODS: The Registry began operating on March 18th, 2020. It collects epidemiological variables, contagion and diagnosis data, signs and symptoms, treatments and outcomes. It is an online registry. Patients were diagnosed with SARS-CoV-2 infection based on the results of the PCR of the virus, carried out both in patients who had manifested compatible symptoms or had suspicious signs, as well as in those who had undergone screening after some contact acquainted with another patient. RESULTS: As of April 11, the Registry had data on 868 patients, from all the Autonomous Communities. The most represented form of RRT is in-center hemodialysis (ICH) followed by transplant patients. Symptoms are similar to the general population. A very high percentage (85%) required hospital admission, 8% in intensive care units. The most used treatments were hydroxychloroquine, lopinavir-ritonavir, and steroids. Mortality is high and reaches 23%; deceased patients were more frequently on ICH, developed pneumonia more frequently, and received less frequently lopinavir-ritonavir and steroids. Age and pneumonia were independently associated with the risk of death. CONCLUSIONS: SARS-CoV-2 infection already affects a significant number of Spanish patients on RRT, mainly those on ICH, hospitalization rates are very high and mortality is high; age and the development of pneumonia are factors associated with mortality.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Nefrologia/estatística & dados numéricos , Pandemias , Pneumonia Viral/epidemiologia , Sistema de Registros/estatística & dados numéricos , Terapia de Substituição Renal/estatística & dados numéricos , Fatores Etários , Idoso , COVID-19 , Distribuição de Qui-Quadrado , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/mortalidade , Feminino , Unidades Hospitalares de Hemodiálise/estatística & dados numéricos , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/mortalidade , SARS-CoV-2 , Sociedades Médicas , Espanha/epidemiologia , Estatísticas não Paramétricas , Avaliação de Sintomas/estatística & dados numéricos , Transplantados/estatística & dados numéricos
10.
Ultrasonics ; 91: 10-18, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30029075

RESUMO

The purpose of this work was to develop a metamodel (Kriging model) to identify the most important input parameters of shock wave pressure profiles as used in biomedical applications without solving a large number of differential equations. Shock wave-induced cavitation is involved in several biological effects. During bubble collapse, secondary shock waves and microjets are formed. For some applications, it is desirable to enhance this phenomenon by applying a second shock wave before bubble collapse; however, the delay between the leading shock wave and the second pressure pulse has yet to be optimized. This optimization can be done using numerical analysis. A metamodel that predicts the most convenient ranges for the input variables and provides information on the joint effects between the input variables was tested. Because the metamodel is an analytical expression, running it fifty thousand times and analyzing variables, such as the pressure amplitude, delay between pulses, and pressure rise time, was fast and easy. Furthermore, this method can be a helpful tool to study the joint effect between the input variables and reduce the computation time. The metamodel can also be adapted to analyze simulations based on equations different from the Gilmore-Akulichev formulation, which was used in this study.


Assuntos
Litotripsia/instrumentação , Microbolhas , Modelos Teóricos , Ultrassom , Microfluídica , Estresse Mecânico
13.
Nanotechnology ; 27(45): 455709, 2016 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-27727154

RESUMO

We present a phenomenon concerning electromagnetic enhancement at the heterojunction region of axially heterostructured Si/SiGe nanowires when the nanowire is illuminated by a focused laser beam. The local electric field is sensed by micro Raman spectroscopy, which allows the enhancement of the Raman signal arising from the heterojunction region to be revealed; the Raman signal per unit volume increases at least ten times with respect to the homogeneous Si and SiGe nanowire segments. In order to explore the physical meaning of this phenomenon, a three-dimensional solution of the Maxwell equations of the interaction between the focused laser beam and the nanowire was carried out by finite element methods. A local enhancement of the electric field at the heterojunction was deduced. However, the magnitude of the electromagnetic field enhancement only approaches the experimental one when the free carriers are considered, showing enhanced absorption at the carrier depleted heterojunction region. The existence of this effect promises a way of improving photon harvesting using axially heterostructured semiconductor nanowires.

14.
J Neurol Surg A Cent Eur Neurosurg ; 77(2): 118-29, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26444961

RESUMO

PURPOSE: To study visual perception in patients with anterior temporal lobectomy. MATERIALS AND METHODS: We explored some aspects of visual perception and compared the results obtained from 14 control subjects and 14 patients with unilateral anterior temporal lobectomy. Each group included 7 men and 7 women and the same age distribution (patients and controls: age range 27-48 years; mean 37 years). All subjects underwent a conventional ophthalmic examination and were tested for color perception, stereopsis, texture perception, face recognition, and visual illusions. To quantify color, stereoscopic, and texture perception they performed a visuomotor task that required a rapid response to a visual stimulus. Reaction times were measured under several conditions. RESULTS: Mild visual field defects involving the superior quadrant contralateral to the lobectomy were found in five patients; two other patients presented more severe defects. Lobectomized patients showed a lower number of correct trials than normal subjects when performing tasks involving color and texture perception. These patients also had longer reaction times for color, stereoscopic, and texture stimulus detection. Face recognition and perception of illusory images were preserved after unilateral anterior temporal lobectomy. CONCLUSION: Our data indicate that patients with anterior temporal lobectomy show moderate deficits in color, stereo, and texture perception, with no impairment in complex visual stimuli perception.


Assuntos
Percepção de Profundidade/fisiologia , Ilusões/fisiologia , Lobo Temporal/fisiopatologia , Percepção Visual/fisiologia , Adulto , Lobectomia Temporal Anterior , Percepção de Cores/fisiologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
17.
Cancer Res ; 73(8): 2628-38, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23370326

RESUMO

5'-AMP-activated protein kinase (AMPK) is an energy sensor that controls cell metabolism, and it has been related to apoptosis and cell-cycle arrest. Although its role in metabolic homeostasis is well documented, its function in cancer is much less clear. In this study, we examined the role of AMPK in a mouse model of astrocytoma driven by oncogenic H-Ras(V12) and/or with PTEN deletion based on the common constitutive activation of the Raf/MEK/ERK and PI3K/AKT cascades in human astrocytomas. We also evaluated the activity and role of AMPK in human glioblastoma cells and xenografts. AMPK was constitutively activated in astrocytes expressing oncogenic H-Ras(V12) in parallel with high cell division rates. Genetic deletion of AMPK or attenuation of its activity in these cells was sufficient to reduce cell proliferation. The levels of pAMK were always related to the levels of phosphorylated retinoblastoma (Rb) at Ser804, which may indicate an AMPK-mediated phosphorylation of Rb. We confirmed this AMPK-Rb relationship in human glioblastoma cell lines and xenografts. In clinical specimens of human glioblastoma, elevated levels of activated AMPK appeared especially in areas of high proliferation surrounding the blood vessels. Together, our findings indicate that the initiation and progression of astrocytic tumors relies upon AMPK-dependent control of the cell cycle, thereby identifying AMPK as a candidate therapeutic target in this setting.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Astrocitoma/metabolismo , Transformação Celular Neoplásica/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Astrócitos/metabolismo , Astrocitoma/genética , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Modelos Animais de Doenças , Ativação Enzimática , Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Camundongos , Transporte Proteico , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Pirazóis/farmacologia , Pirimidinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Nefrología (Madr.) ; 32(6): 824-828, nov.-dic. 2012. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-110499

RESUMO

La ateroembolia de colesterol (AEC) es una enfermedad sistémica cuya incidencia ha aumentado en las últimas décadas y que presenta una elevada morbimortalidad. En el momento actual se desconocen cuáles son las alternativas terapéuticas más efectivas en esta entidad. En este artículo presentamos el caso de una paciente diagnosticada de AEC con afectación cutánea, intestinal y renal, que presentó una buena evolución tras el inicio de terapia combinada con esteroides y análogos de las prostaglandinas. A pesar de que no existen estudios concluyentes, sugerimos esta alternativa para el manejo de AEC con afectación orgánica (AU)


Cholesterol atheroembolism (CAE) is a systemic disorder whose incidence has increased in recent decades and that presents high morbidity and mortality. Although several therapeutic alternatives have been reported, there is no consensus about the best treatment for this disease. In this paper we report the case of a patient with CAE with skin, bowel and kidney involvement who presented a good response to combined therapy with steroids and prostaglandin analogues. Although there are no conclusive studies, we recommend this therapeutic alternative in the management of CAE with organic failure (AU)


Assuntos
Humanos , Embolia de Colesterol/tratamento farmacológico , Esteroides/uso terapêutico , Iloprosta/uso terapêutico , Prostaglandinas Sintéticas/uso terapêutico , Fatores de Risco , Suscetibilidade a Doenças
19.
Nefrologia ; 32(6): 824-8, 2012.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23169366

RESUMO

Cholesterol atheroembolism (CAE) is a systemic disorder whose incidence has increased in recent decades and that presents high morbidity and mortality. Although several therapeutic alternatives have been reported, there is no consensus about the best treatment for this disease. In this paper we report the case of a patient with CAE with skin, bowel and kidney involvement who presented a good response to combined therapy with steroids and prostaglandin analogues. Although there are no conclusive studies, we recommend this therapeutic alternative in the management of CAE with organic failure.


Assuntos
Embolia de Colesterol/tratamento farmacológico , Iloprosta/uso terapêutico , Esteroides/uso terapêutico , Idoso , Quimioterapia Combinada , Feminino , Humanos
20.
Acta Neurol Belg ; 111(3): 228-31, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22141290

RESUMO

A 40 year-old woman with subacute headache and visual impairment was admitted. Neurological examination revealed meningismus, diminished visual acuity, bilateral sixth cranial nerve palsy, and papillary edema. Dermatologic examination was normal. The brain CT scan showed hydrocephalus and hyperdense edging around fissures and sulci. The CSF study showed an increased protein level, with persistently negative microbiologic and cytological studies. Prior to Gd-DPTA injection, the brain T1-WI MRI revealed leptomeningeal hyperintensity. A dark subpial substance became evident at cerebral biopsy. The histopatological diagnosis was diffuse leptomeningeal melanomatosis. This case report highlights the diagnostic value of the brain MRI findings in primary leptomeningeal melanomatosis, a rare pathologic condition diagnosed in most published cases only after necropsy. Meningeal T1-WI hyperintensity prior to contrast injection is not caused by sarcoidosis or meningeal carcinomatosis, lymphomatosis or gliomatosis.


Assuntos
Imageamento por Ressonância Magnética , Melanoma/patologia , Neoplasias Meníngeas/patologia , Meninges/patologia , Adulto , Cegueira/etiologia , Cegueira/patologia , Evolução Fatal , Feminino , Humanos , Hidrocefalia/etiologia , Hidrocefalia/patologia , Melanoma/complicações , Neoplasias Meníngeas/complicações , Meningismo/etiologia , Meningismo/patologia
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