Quality of private and public ambulatory health care in low and middle income countries: systematic review of comparative studies

Paul Garner and colleagues conducted a systematic review of 80 studies to compare the quality of private versus public ambulatory health care in low- and middle-income countries

Ceramic sonotrodes for light alloy melt treatment

Alloy melt treatment by ultrasonic vibration is a physical processing technique that has been gathering the support of the scientific community. The use of metallic sonotrodes for this purpose has been proven very efficient; however, it promotes melt inclusion by sonotrode erosion. Such an issue is being addressed by the use of ceramic sonotrodes in low-amplitude resonance. Given that these novel sonotrodes generally have complex shapes and low displacements, this study shows an innovative approach for their characterization. Based on scanning laser Doppler vibrometry, the signal processing Python-based script was used to map the overall resonant behavior of a tubular SiAlON sonotrode, and this route is able to characterize the complex shapes in low-amplitude and high-frequency radial resonance in resonant ceramic sonotrodes. Velocity time-domain profiles are shown to be dependent on the position, and even though the radial natural frequencies of ceramic sonotrodes have low amplitudes, they are proposed as an efficient tool for melt treatment. While characterizing the radial natural mode in ceramic sonotrodes, this study proves that their low-amplitude Lamb waves are responsible for the refinement of a-grains and secondary phases in light alloys.This work was supported by PTDC/EMEEME/30967/ 2017 and NORTE-0145-FEDER-030967, co-financed by the European Regional Development Fund (ERDF), through the Operational Programme for Competitive ness and Internationalization (COMPETE 2020), under Portugal 2020, and by the Fundação para a Cência e a Tecnologia – FCT I.P. national funds. Also, this work was supported by Portuguese FCT, under the reference project UIDB/04436/2020, and Stimulus of Scientific Employment Application CEECIND/03991/2017

Stability of bandwidth request control based on dual feedback in BWA networks

In order for the base station to respond quickly and efficiently to the uplink bandwidth request in broadband wireless access (BWA) networks using time-division duplex (TDD), a dual feedback control algorithm has recently been proposed [3]. In this algorithm the bandwidth request is adjusted in accordance with both the length of the backlogged queue and the mismatch between packet arrival and service rates. This paper presents a thorough study of the stability of the dual feedback algorithm in both continuous-time and discrete-time domains. It turns out that the stability condition in [3] is necessary but not sufficient to guarantee the stability of its discrete-time implementation. ©2009 IEEE

An FSMC model for the ACM scheme with repetition coding in mobile WiMAX

To protect vital control information from deep fades, repetition coding is recommended in mobile WiMAX. This paper considers repetition coding as a maximum ratio combining process and proposes an expression for the coding gain and its effect on BER. A 10-state finite state Markov channel (FSMC) model is also proposed for the implementation of the adaptive modulation and coding (AMC) scheme in mobile WiMAX to maximize its spectral efficiency in a Rayleigh fading environment. ©2009 IEEE

Two composite fading models for diversity reception in mobile wireless networks

Composite Rayleigh-lognormal fading, also known as Suzuki fading, is a cascaded product of a multipath fast fading channel and a shadowing slow fading channel. In spatial diversity reception using maximum ratio combining, the Suzuki fading model only provides diversity in the local multipath fast fading Rayleigh component, here called the micro-diversity fading model. In this paper, we propose the macro-diversity composite fading model by which diversity is obtained over the whole transmission link from the transmitter to the mobile receiver, ie. in both the slow lognormal fading and the fast Rayleigh fading. Methods for solving the "sum of Suzuki random variables" problem involved in the macro-diversity model is presented in the paper. The GaussHermite quadrature polynomial is extensively used to avoid sensitive integrations and to derive elegant and computationally fast closed-form expressions for bit error rate of micro-diversity and macro-diversity reception in mobile networks. © Institution of Engineers Australia 2013

Spatial prediction of rainfall-induced landslides for the Lao Cai area (Vietnam) using a hybrid intelligent approach of least squares support vector machines inference model and artificial bee colony optimization

© 2016, Springer-Verlag Berlin Heidelberg. The main objective of this study is to produce a landslide susceptibility map for the Lao Cai area (Vietnam) using a new hybrid intelligent method based on least squares support vector machines (LSSVM) and artificial bee colony (ABC) optimization, namely LSSVM-BC. LSSVM and ABC are state-of-the-art soft computing techniques that have been rarely utilized in landslide susceptibility assessment. LSSVM is adopted to develop landslide prediction model whereas ABC was used to optimize the prediction model by identifying an appropriate set of the LSSVM hyper-parameters. To establish the hybrid intelligent method, a GIS database with ten landslide-influencing factors and 340 landslide locations that occurred mainly during the last 20-years was constructed. These historical landslide locations were collected from the existing inventories that sourced from (i) five landslide projects carried out in this study areas before and (ii) interpretations of SPOT satellite images with resolution of 2.5 m. The study area was geographically split into two different parts, with landslides located in the first part was used for building models whereas the other landslides in the second part was used for the model validation. Performance of the LSSVM-BC model was assessed using the receiver operating characteristic (ROC) curve and area under the curve (AUC). Result shows that the prediction power of the model is good with the area under the curve (AUC) = 0.900. Experiments have pointed out the prediction power of the LSSVM-BC is better than that obtained from the popular support vector machines. Therefore, the proposed model is a promising tool for spatial prediction of landslides at the study area. The landslide susceptibility map is useful for landuse planning for the Lao Cai area

Minimally Invasive Treatment of Chyle Leak After Thyroidectomy and Cervical Lymph Node Dissection in Patients with Thyroid Carcinoma: Results of a Study Involving 36 Patients

Nguyen Ngoc Cuong,1,* Le Hoan,2,* Thieu Thi Tra My,3 Doan Tien Luu,1 Le Tuan Linh,1 Pham Hong Canh,1 Trieu Quoc Tinh,1 Tran Nguyen Khanh Chi,1 Nguyen Quang Trung,1 Tran Quoc Hoa4 1Diagnostic Imaging and Interventional Center, Hanoi Medical University Hospital, Ha Noi, Viet Nam; 2Respiratory Department, Hanoi Medical University Hospital, Ha Noi, Viet Nam; 3Diagnostic Imaging and Nuclear Medicine Department, Vinmec Times City International Hospital, Ha Noi, Viet Nam; 4Urology Surgery department, Hanoi Medical university, Ha Noi, Viet Nam*These authors contributed equally to this workCorrespondence: Nguyen Ngoc Cuong, Diagnostic Imaging and Interventional Center, Hanoi Medical University Hospital, No. 1, Ton That Tung, Dong Da, Ha Noi, Viet Nam, Email [email protected]: Chyle leak (CL) after head and neck surgery is a rare but well-known complication. In patients with high-output leakage, the treatment can be complicated. This study aims to report on a recent innovation in lymphatic intervention for treating such patients.Materials and Methods: A retrospective review of 36 patients with chyle leak after neck surgery for thyroid cancer was conducted to assess the efficacy of percutaneous lymphatic embolization and thoracic duct (TD) disruption.Results: Antegrade catheterization of the thoracic duct was achieved in 31 of 36 patients (86.1%). Therefore, embolization of the thoracic duct and thoracic duct branches was performed in 26 and 5 patients, respectively. In 5 cases of unsuccessful antegrade catheterization into the thoracic duct, transcervical access embolization was performed in 2 patients, and TD disruption (TDD) was performed in 3 patients. The pooled overall technical success rate of lymphatic embolization was 33/36 patients (91.7%). One patient who underwent thoracic duct embolization (TDE) with technical success (1/33 patients) but clinical failure had additional treatment directly sclerosing the TD under computed tomography scan. Cervical fluid collection sclerotherapy was done in 7 patients as an additional treatment. Resolution of the chyle leak after procedures was observed in all patients (100%). The mean time to resolution was 3 days (1– 7 days). There was no complication intra and after procedures.Conclusion: TDE, selective TD branches embolization and TDD are safe and effective minimally invasive treatments for CL post-surgery for thyroid carcinoma. Sclerosing cervical fluid collection contributes to clinical success.Keywords: thyroid cancer, thyroidectomy, chyle leak, thoracic duct embolization, thoracic duct disruption, sclerotherap

Avaliação do desempenho de um reator anaeróbio de fluxo vertical com separação de fases no tratamento de manipueira / Evaluation of the performance of a vertical flow anaerobic reactor with phase separation in treatment of cassava wastewater

O presente trabalho teve por objetivo analisar a eficiência do tratamento da manipueira em um reator anaeróbio de duas fases com volume útil de 8 L em cada fase, onde o mesmo foi operado com vazão de 2 L.dia-1 e TDH de 8 dias. Foram analisados os parâmetros físico-químicos: temperatura, pH, ácidos voláteis, alcalinidade total, demanda química de oxigênio (DQO), nitrogênio total kjeldahl (NTK), sólidos voláteis e turbidez. Os resultados obtidos indicaram que o sistema de tratamento apresentou uma redução de aproximadamente 90% nos valores de turbidez, 60%, 40% e 40% de eficiência de remoção de sólidos voláteis, DQO e NTK, respectivamente. Dessa forma, o reator anaeróbio de fluxo vertical com separação das fases, se mostrou com grande potencial para o tratamento da manipueira, podendo ter sua eficiência aumentada com a utilização de dosagens de alcalinizantes para neutralizar a acidez natural da manipueira, principalmente durante a partida do reator, a fim de evitar a acidificação do efluente e redução da eficiência do biorreator.

Model predictive control for improving operational efficiency of overhead cranes

Model predictive control (MPC) has been successfully applied to many transportation systems. For the control of overhead cranes, existing MPC approaches mainly focus on improving the regulation performance, such as tracking error or steady-state error. In this paper, energy efficiency as well as safety is newly considered in our proposed MPC approach. Based on the system model designed, the MPC approach is applied to minimize an objective function that is formulated as the integration of energy consumption and swing angle. In our approach, promising results in terms of low energy consumption and small swing angle can be found, whilst the solutions obtained can satisfy all practical constraints. Our test results indicate that the MPC approach can ensure stability and robustness of improving energy efficiency and safety.http://link.springer.com/journal/110712016-03-31hb201

Effect of antituberculosis drug resistance on response to treatment and outcome in adults with tuberculous meningitis.

BACKGROUND: Tuberculous meningitis (TBM) caused by Mycobacterium tuberculosis resistant to 1 or more antituberculosis drugs is an increasingly common clinical problem, although the impact on outcome is uncertain. METHODS: We performed a prospective study of 180 Vietnamese adults admitted consecutively for TBM. M. tuberculosis was cultured from the cerebrospinal fluid (CSF) of all patients and was tested for susceptibility to first-line antituberculosis drugs. Presenting clinical features, time to CSF bacterial clearance, clinical response to treatment, and 9-month morbidity and mortality were compared between adults infected with susceptible and those infected with drug-resistant organisms. RESULTS: Of 180 isolates, 72 (40.0%) were resistant to at least 1 antituberculosis drug, and 10 (5.6%) were resistant to at least isoniazid and rifampicin. Isoniazid and/or streptomycin resistance was associated with slower CSF bacterial clearance but not with any differences in clinical response or outcome. Combined isoniazid and rifampicin resistance was strongly predictive of death (relative risk of death, 11.63 [95% confidence interval, 5.21-26.32]) and was independently associated with human immunodeficiency virus infection. CONCLUSIONS: Isoniazid and/or streptomycin resistance probably has no detrimental effect on the outcome of TBM when patients are treated with first-line antituberculosis drugs, but combined isoniazid and rifampicin resistance is strongly predictive of death