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Introduction: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with increased prevalence in recent years. One of the extra skeletal functions of vitamin D is involved in regulation of immune response. Objectives: This study was to determine vitamin D status in SLE patients and the relationship with disease activity. Methods: This prospective observational study was conducted at Medicine department in Dhaka Medical College and Hospital. Data regarding disease activity of SLE was taken from 50 SLE patients fulfilling ACR criteria and disease activity was calculated by SLEDAI score. Vitamin D level was quantified by ELISA. Results: Out of 50 patients, 46(92%) were female and 4(8%) were male. Age range was 15 to 65 years and mean age was 28.00 ± 13.34 SD. Most of the population reside in rural areas (n=32, 64%) and rest from urban areas (n=18,36%). Common presentations were fever (62%), proteinuria (50%), rash (40%), vasculitis (36%) and hematuria (34%). Overall mean SLEDAI score was 18.24 ± 9.67. Among the study population, 21(42%) patients had very highly active disease, 12(24%) patients had highly active disease, 11(22%) patients had moderately active disease and 6(12%) patients had mildly active disease. Mean vitamin D level was 16.70 ± 8.83 ng/ml. In this study, majority were found to be vitamin D deficient 37(74%), out of rest 7(14%) patients had insufficient vitamin D level and 6(12%) patients had sufficient vitamin D. This study showed that there is negative linear correlation between SLEDAI score and vitamin D level which is statistically significant (p value

Aims: Socioeconomic and environmental factors influence childhood asthma prevalence across the world. In-depth epidemiological research is necessary to determine the association between asthma prevalence and socio-environmental conditions, and to develop public health strategies to protect the asthmatic children against the environmental precipitators. Our research was based on aggregative data and sought to compare the asthma prevalence between children of two different age-groups across the world and to identify the association among the key socio-environmental conditions with increased childhood asthma prevalence. Method: We included forty countries with available data on various socio-environmental conditions (2014-2015). Childhood asthma prevalence of two different age groups (6-7 and 13-14 years) were obtained from global asthma report 2014. Because of significant diversities, the selected countries were divided into two groups based on human developmental index (HDI), a well-recognized parameter to estimate the overall socioeconomic status of a country. Robust linear regression was conducted using childhood asthma prevalence as the dependent variable and female smoking prevalence, tertiary school enrollment (TSE), PM10 (particulate matter ≤10 μm in diameter) and gross domestic product (GDP) as predictors. Results: Asthma prevalence was not different between two age groups. Among all predictors, only female smoking prevalence (reflecting maternal smoking) was associated with asthma prevalence in the countries with lower socio-economic conditions (HDI), but not in the higher HDI group. The results were unchanged even after randomization. Conclusions: Childhood asthma prevalence did not change significantly with age. Female smoking may have a positive correlation with childhood asthma prevalence in lower HDI countries.

e18005Background: Patients with recurrent/ metastatic head and neck squamous cell carcinoma (HNSCC) with poor performance status (PS) have limited treatment options. Immune mechanisms are implicate...

6046Background: Cisplatin ( Cis) is one of the most ototoxic chemotherapy drugs, resulting in a permanent and irreversible hearing loss in up to 50% of patients. Little is known about the incidence...

Effects of pedestrian movement on multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) channel capacity have been investigated using experiment and simulation. The experiment was conducted at 5.2 GHz by a MIMO-OFDM packet transmission demonstrator using four transmitters and four receivers built in-house. Geometric optics-based ray-tracing technique was used to simulate the experimental scenarios. Changes in the channel capacity dynamic range have been analyzed for different numbers of pedestrian (03) and antennas (24). Measurement and simulation results show that the dynamic range increases with the number of pedestrians and the number of antennas on the transmitter and receiver array.

In the last few decades the use of aluminium and its alloys have increased to a high level due to its light weight, corrosion resistance and excellent castability. It is well known that most of the metal parts are manufactured by machining. In the era of modern manufacturing CNC milling has become one of the most competent, productive and flexible manufacturing methods. Thus different controlling parameters like, spindle speed, feed rate, depth of cut, tool geometry, tool material, coolant have high influence on the surface texture of the machined product. Hence in this study, the effect of three important machining parameters viz., cutting speed, feed rate and depth of cut on the surface roughness (centre line average and ten point height roughness) has been investigated. The optimum combination of these parameters has also been determined for single and multi objective function by two evolutionary optimisation methods (ABC and GA) and compared.

We investigate Multiple-Input and Multiple-Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) systems behavior in indoor populated environments that have line-of-site (LoS) between transmitter and receiver arrays. The in-house built MIMO-OFDM packet transmission demonstrator, equipped with four transmitters and four receivers, has been utilized to perform channel measurements at 5.2 GHz. Measurements have been performed using 0 to 3 pedestrians with different antenna arrays (2 × 2, 3 × 3 and 4 × 4). The maximum average capacity for the 2×2 deterministic Fixed SNR scenario is 8.5 dB compared to the 4×4 deterministic scenario that has a maximum average capacity of 16.2 dB, thus an increment of 8 dB in average capacity has been measured when the array size increases from 2×2 to 4×4. In addition a regular variation has been observed for Random scenarios compared to the deterministic scenarios. An incremental trend in average channel capacity for both deterministic and random pedestrian movements has been observed with increasing number of pedestrian and antennas. In deterministic scenarios, the variations in average channel capacity are more noticeable than for the random scenarios due to a more prolonged and controlled body-shadowing effect. Moreover due to the frequent Los blocking and fixed transmission power a slight decrement have been observed in the spread between the maximum and minimum capacity with random fixed Tx power scenario.

Channel measurements and simulations have been carried out to observe the effects of pedestrian movement on multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) channel capacity. An in-house built MIMO-OFDM packet transmission demonstrator equipped with four transmitters and four receivers has been utilized to perform channel measurements at 5.2 GHz. Variations in the channel capacity dynamic range have been analysed for 1 to 10 pedestrians and different antenna arrays (2×2, 3×3 and 4 × 4). Results show a predicted 5.5 bits/s/Hz and a measured 1.5 bits/s/Hz increment in the capacity dynamic range with the number of pedestrian and the number of antennas in the transmitter and receiver array.

Temporal variations caused by pedestrian movement can significantly affect the channel capacity of indoor MIMO-OFDM wireless systems. This paper compares systematic measurements of MIMO-OFDM channel capacity in presence of pedestrians with predicted MIMO-OFDM channel capacity values using geometric optics-based ray tracing techniques. Capacity results are presented for a single room environment using 5.2 GHz with 2×2, 3×3 and 4×4 arrays as well as a 2.45 GHz narrowband 8×8 MIMO array. The analysis shows an increase of up to 2 b/s/Hz on instant channel capacity with up to 3 pedestrians. There is an increase of up to 1 b/s/Hz in the average capacity of the 4×4 MIMO-OFDM channel when the number of pedestrians goes from 1 to 3. Additionally, an increment of up to 2.5 b/s/Hz in MIMO-OFDM channel capacity was measured for a 4×4 array compared to a 2×2 array in presence of pedestrians. Channel capacity values derived from this analysis are important in terms of understanding the limitations and possibilities for MIMO-OFDM systems in indoor populated environments.

Insufficient Quality of Service (QoS) of Voice over Internet Protocol (VoIP) is a growing concern that has lead the need for research and study. In this paper we investigate the performance of VoIP and the impact of resource limitations on the performance of Access Networks. The impact of VoIP performance in Access Networks is particularly important in regions where Internet resources are limited and the cost of improving these resources is prohibitive. It is clear that perceived VoIP performance, as measured by mean opinion score [2] in experiments, where subjects are asked to rate communication quality, is determined by end-to-end delay on the communication path, delay variation, packet loss, echo, the coding algorithm in use and noise. These performance indicators can be measured and the affect in the Access Network can be estimated. This paper investigates the congestion in the Access Network to the overall performance of VoIP services with the presence of other substantial uses of internet and ways in which Access Networks can be designed to improve VoIP performance. Methods for analyzing the impact of the Access Network on VoIP performance will be surveyed and reviewed. This paper also considers some approaches for improving performance of VoIP by carrying out experiments using Network Simulator version 2 (NS2) software with a view to gaining a better understanding of the design of Access Networks.

This paper presents a systematic study of input and multiple-output orthogonal frequency division multiplexing (MIMO-OFDM) systems behavior in an indoor environment in the presence of deterministic and random human movement between transmitter and receiver array. The in-house built MIMO-OFDM packet transmission demonstrator, equipped with four transmitters and four receivers, has been utilized to perform channel measurements at 5.2 GHz. Measurements have been performed using 0–3 pedestrians with different antenna arrays (2 × 2, 3 × 3 and 4 × 4). Regular significant temporal variation has been observed for random scenarios compared to the deterministic scenarios. An incremental trend in average channel capacity for both deterministic and random pedestrian movements has been observed as a function of the number of the pedestrian and antennas. The 90% dynamic range analysis also reserved the incremental affinity with the increasing number of pedestrian and antenna combinations.