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In the neighborhood area network (NAN), the advanced metering infrastructure (AMI) enables a bidirectional connection between the smart meter (SM) and the data concentrator (DC). Sensors, such as smart meter nodes or environmental sensor nodes, play a crucial role in measuring and transmitting data to central units for advanced monitoring, management, and analysis of energy consumption. Wired and wireless communication technologies are used to implement the AMI-NAN. This paper delves into a novel approach for optimizing the choice of communication medium, air for radio frequency (RF) or power lines for power line communication (PLC), between the SM and DC in the context of the AMI-NAN. The authors methodically select the specific technologies, RF and NB-PLC (narrowband power line communication), and meticulously characterize their attributes. Then, a comparative analysis spanning rural, urban, and industrial settings is conducted to evaluate the proposed method. The overall reliability performance of the AMI-NAN system requires a packet error rate (PER) lower than 10%. To this end, an efficient approach is introduced to assess and enhance the reliability of NB-PLC and RF for AMI-NAN applications. Simulation results demonstrate that wireless communication is the optimal choice for the rural scenario, especially for a signal-to-noise ratio (SNR) lower than 25 dB. However, in urban environments characterized by higher SNR values and moderately dense networks, NB-PLC gains prominence. In denser networks, it outperforms wireless communication, exhibiting a remarkable 10 dB gain for a bit error rate (BER) of 10-3. Moreover, in industrial zones characterized by intricate network topologies and non-linear loads, the power line channel emerges as the optimal choice for data transmission.
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This paper presents a compression study of electrocardiogram (ECG) signals for e-Health cardiac online diagnostic systems. The study uses 75 real electrocardiogram records sampled with continuous-time level-crossing (LC) analog-to-digital converter (ADC). This signal-dependent LC-ADC compresses signals compared to conventional ADC but further compression is needed especially for long-time monitoring applications. The orthogonal matching pursuit algorithm is simulated to evaluate ECG compression with 54 orthogonal and biorthogonal wavelets. For LC-ADC amplitude output compression, Biorthogonal3.1 (bior3.1) wavelet achieves optimal performances in terms of compression ratio (CR) while ensuring 2-% percentage root-mean-square difference (PRD). The PRD must be limited to this value to ensure a very good quality signals after decompression. For circuit implementation purposes, bior3.1 wavelet is proposed as a multiplier-free decomposition step and a noncomplex global and hard thresholding process is achieved. The average CR is 63% and PRD varies between 0.1 and 2.1% leading to a very good diagnostic quality.
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Wolman disease is an ultrarare lysosomal storage disease caused by a mutation in the LIPA gene. The clinical features of Wolman disease include early onset of vomiting, diarrhea, failure to thrive, hepatosplenomegaly, and bilateral adrenal calcification. We report the case of a 3-month-old infant who presented clinical features of hemophagocytic lymphohistiocytosis. Genetic sequence analysis of the LIPA gene revealed homozygous mutation c.153 C>A (p.Tyr51*). The parents were heterozygous for this mutation. Prenatal diagnosis has been carried out in the next pregnancy. To our knowledge, this mutation has never been reported before, and this is an unusual case of secondary hemophagocytic lymphohistiocytosis complicating Wolman disease.
Asunto(s)
Linfohistiocitosis Hemofagocítica/etiología , Mutación , Enfermedad de Wolman/complicaciones , Diagnóstico Diferencial , Femenino , Homocigoto , Humanos , Lactante , Linfohistiocitosis Hemofagocítica/diagnóstico , Diagnóstico Prenatal , Análisis de Secuencia de ADN , Esterol Esterasa/genética , Túnez , Enfermedad de Wolman/diagnóstico , Enfermedad de Wolman/genéticaRESUMEN
BACKGROUND: Acute bronchiolitis management involves all pediatricians and primary care physicians. The national guidelines for bronchiolitis diagnosis and treatment were published in Tunisia to reduce excessive use of diagnostic tests and unify bronchiolitis management. OBJECTIVES: We aimed to assess the real impact of the national guidelines on acute bronchiolitis management in Tunisia. METHODS: We conducted an evaluative cross-sectional study. We randomly distributed anonymous questionnaires to physicians managing acute bronchiolitis during the period from 1st March 2014 to 30 November 2015. RESULTS: We analyzed 140 questionnaires. Ninety-three interviewed physicians (66.4%) were advised of the latest national guidelines, half of them (33.6%) declared they didn't follow these guidelines. Real and complete guidelines adherence was observed in only 1.4% of interviewed physicians. According to bronchiolitis diagnosis, appropriate Chest X-rays and blood tests were requested respectively by 57.8% and 59.3% of interviewed doctors. Regarding bronchiolitis therapeutic management, bronchodilators and epinephrine nebulization weren't prescribed by respectively 45.7% and 38.6% of them. Antibiotics were prescribed by 92.9% of interviewed doctors and chest physiotherapy was well indicated by 47.8% of them. CONCLUSIONS: There is a disconnect between the bronchiolitis guidelines and clinical practice. National strategies have to be developed to reduce excessive use of diagnostic tests and unrecommanded therapies.
Asunto(s)
Bronquiolitis , Pautas de la Práctica en Medicina , Enfermedad Aguda , Bronquiolitis/diagnóstico , Bronquiolitis/epidemiología , Bronquiolitis/terapia , Estudios Transversales , Humanos , Túnez/epidemiologíaRESUMEN
The long-term monitoring of cardiovascular signs requires a wearable and connected electrocardiogram (ECG) healthcare device. It increases user's comfort and diagnosis quality of chronic cardiac and/or high-risk patients. This paper covers the enormous data to be transmitted from the ECG device to the physician's, namely the cardiologist's, control unit. Existent ECG devices uniformly sample analog signals and convert them to digital samples which are compressed before data transmission. However, event-driven sampling simultaneously compresses and samples. Therefore, this paper quantitatively compares successive approximation register analog-to-digital converter (SAR ADC) with discrete wavelet transform (DWT) compression and level-crossing analog-to-digital converter (LC-ADC). Evaluation metrics are the percent root-mean-square difference ( PRD ), bit compression ratio ( BCR ) and data length in bits. When a 12-bit reconstruction is operated on the outputs of an 8-bit LC-ADC with 12-bit and 10-kHz reference counter, the BCR is equal to 80% for 75% of test ECG signals. That is better than the 71.87% BCR of the 12-bit 1-kHz SAR ADC with DWT compression. The modeled LC-ADC guarantees a signal quality in terms of PRD comparable to the PRD of the SAR ADC with DWT compression. The data length in bits of the LC-ADC is lower than the data length in bits of the SAR ADC with more than 14-bit resolution with DWT compression for 82% of the test ECG signals. However, for lower resolutions, to obtain lower power consumption for radiofrequency transmission, a better alternative remains the SAR ADC with DWT compression.