24 research outputs found
An Energy Efficient MAC Protocol for QoS Provisioning in Cognitive Radio Ad Hoc Networks
The explosive growth in the use of real-time applications on mobile devices has resulted in new challenges to the design of medium access control (MAC) protocols for ad hoc networks. In this paper, we propose an energy efficient cognitive radio (CR) MAC protocol for QoS provisioning called ECRQ-MAC, which integrate the spectrum sensing at physical (PHY) layer and the channel-timeslots allocation at MAC layer. We consider the problem of providing QoS guarantee to CR users as well as to maintain the most efficient use of scarce bandwidth resources. The ECRQ-MAC protocol exploits the advantage of both multiple channels and TDMA, and achieves aggressive power savings by allowing CR users that are not involved in communication to go into sleep mode. The proposed ECRQ-MAC protocol allows CR users to identify and use the unused frequency spectrum of licensed band in a way that constrains the level of interference to the primary users (PUs). Our scheme improves network throughput significantly, especially when the network is highly congested. The simulation results show that our proposed protocol successfully exploits multiple channels and significantly improves network performance by using the licensed spectrum opportunistically and protects QoS provisioning over cognitive radio ad hoc networks
Quantifying recreational value and the functional relationship between travel cost and visiting national park
Abstract Estimation of recreational benefits is an important tool for both biodiversity conservation and ecotourism development in national parks and sanctuaries. The design of this work is to estimate the recreational value and to establish functional relationship between travel cost and visitation of Lawachara National Park (LNP) in Bangladesh. This study employed zonal approach of the travel cost method. The work is grounded on a sample of 422 visitors of the LNP. Results showed that the total value of environmental assets of the LNP is 55,694,173 Taka/Year. Moreover, our suggestion based on visitors' willingness to pay is that the park entrance fee of 25 Tk per person should be introduced that could generate revenue approximate 2.3 million Taka/ year, beneficial for the park management and conservation of biodiversity
Electrocardiographic findings and prognostic values in patients hospitalised with COVID-19 in the World Heart Federation Global Study
BACKGROUND
COVID-19 affects the cardiovascular system and ECG abnormalities may be associated with worse prognosis. We evaluated the prognostic value of ECG abnormalities in individuals with COVID-19.
METHODS
Multicentre cohort study with adults hospitalised with COVID-19 from 40 hospitals across 23 countries. Patients were followed-up from admission until 30 days. ECG were obtained at each participating site and coded according to the Minnesota coding criteria. The primary outcome was defined as death from any cause. Secondary outcomes were admission to the intensive care unit (ICU) and major adverse cardiovascular events (MACE). Multiple logistic regression was used to evaluate the association of ECG abnormalities with the outcomes.
RESULTS
Among 5313 participants, 2451 had at least one ECG and were included in this analysis. The mean age (SD) was 58.0 (16.1) years, 60.7% were male and 61.1% from lower-income to middle-income countries. The prevalence of major ECG abnormalities was 21.3% (n=521), 447 (18.2%) patients died, 196 (8.0%) had MACE and 1115 (45.5%) were admitted to an ICU. After adjustment, the presence of any major ECG abnormality was associated with a higher risk of death (OR 1.39; 95% CI 1.09 to 1.78) and cardiovascular events (OR 1.81; 95% CI 1.30 to 2.51). Sinus tachycardia (>120 bpm) with an increased risk of death (OR 3.86; 95% CI 1.97 to 7.48), MACE (OR 2.68; 95% CI 1.10 to 5.85) and ICU admission OR 1.99; 95% CI 1.03 to 4.00). Atrial fibrillation, bundle branch block, ischaemic abnormalities and prolonged QT interval did not relate to the outcomes.
CONCLUSION
Major ECG abnormalities and a heart rate >120 bpm were prognostic markers in adults hospitalised with COVID-19
Quantifying Recreational Value and the Functional Relationship Between Travel Cost and Visiting National Park
Abstract Estimation of recreational benefits is an important tool for both biodiversity conservation and ecotourism development in national parks and sanctuaries. The design of this work is to estimate the recreational value and to establish functional relationship between travel cost and visitation of Lawachara National Park (LNP) in Bangladesh. This study employed zonal approach of the travel cost method. The work is grounded on a sample of 422 visitors of the LNP. Results showed that the total value of environmental assets of the LNP is 55,694,173 Taka/Year. Moreover, our suggestion based on visitors' willingness to pay is that the park entrance fee of 25 Tk per person should be introduced that could generate revenue approximate 2.3 million Taka/ year, beneficial for the park management and conservation of biodiversity
Intestinal toxicity to CTLA-4 blockade driven by IL-6 and myeloid infiltration
View full abstracthttps://openworks.mdanderson.org/leading-edge/1055/thumbnail.jp
Canagliflozin and Renal Outcomes in Type 2 Diabetes and Nephropathy
BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodiumâglucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to 300 to 5000) and were treated with reninâangiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m 2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years
Canagliflozin and renal outcomes in type 2 diabetes and nephropathy
BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodiumâglucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with reninâangiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years
ANALISIS POLA DISTRIBUSI SPASIAL PERUBAHAN PENGGUNAAN LAHAN DAN URBAN HEAT ISLAND MENGGUNAKAN GOOGLE EARTH ENGINE (STUDI KASUS DI KOTA BOGOR TAHUN 2000, 2009, & 2021)
Bogor merupakan salah satu kota tertua di Indonesia dan salah satu kota terbesar di Jabodetabek (Jakarta, Bogor, Depok, Tanggerang, dan Bekasi). Kota Bogor juga merupakan pusat ekonomi dan salah satu kota yang memiliki jumlah populasi yang cukup tinggi, hal ini berpengaruh pada peningkatan pertumbuhan perkotaan. Akan tetapi urbanisasi dapat memberikan dampak negatif terhadap lingkungan dan kesehatan manusia terutama pada produksi polusi gas CO2, modifikasi sifat fisik dan kimia atmosfer, yang dapat menyebabkan perubahan cuaca lokal dan iklim hal itu dapat menyebabkan peningkatan suhu di Kawasan perkotaan yang dikenal dengan fenomena Urban Heat Island (UHI). Berdasarkan hal tersebut, maka perlu dimonitoring melalui pengindraan jauh, pengindraan jauh adalah salah satu sarana yang efektif dalam pemantauwan penggunaan lahan karna dapat menyediakan informasi mengenai permukaan bumi, Salah satu teknologi pengindraan jauh yakni Google Earth Engine, adalah sebuah platform berbasis cloud yang menawarkan analisis data lingkungan berskala dunia dimana User hanya perlu mengakses data dari repository di google untuk mendapatkan citra data pengindraan jauh dan data geospasial lain .Pendekatan penelitian ini menggunakan metode Random Forest sebagai pembelajaran ansamble untuk memecahkan masalah klasifikasi dan regresi. metode ini memiliki akurasi yang cukup tinggi serta bisa menentukan variabel-variabel penting dan meminimalisasi kesalahan penilaian akan membuat analisis menjadi lebih praktis dan lebih mudah. Hasil dari penelitian ini didapatkan bahwa urbanisasi perkotaan selalu meningkat dan suhu rata-rata Kota Bogor dari tahun 2000 hingga tahun 2021 mengalami peningkat pada setiap tahunnya. adapun hasil klasifikasi tutupan lahan dari penelitian ini menggunakan metode Random Forest (RF) menunjukkan nilai akurasi keseluruhan (Overall Accuracy) sebesar 95,57% dan nilai kappa sebesar 94,56%
A Schedule-based Multi-channel MAC Protocol for Wireless Sensor Networks
Due to the half-duplex property of the sensor radio and the broadcast nature of wireless medium, limited bandwidth remains a pressing issue for wireless sensor networks (WSNs). The design of multi-channel MAC protocols has attracted the interest of many researchers as a cost effective solution to meet the higher bandwidth demand for the limited bandwidth in WSN. In this paper, we present a scheduled-based multi-channel MAC protocol to improve network performance. In our protocol, each receiving node selects (schedules) some timeslot(s), in which it may receive data from the intending sender(s). The timeslot selection is done in a conflict free manner, where a node avoids the slots that are already selected by others in its interference range. To minimize the conflicts during timeslot selection, we propose a unique solution by splitting the neighboring nodes into different groups, where nodes of a group may select the slots allocated to that group only. We demonstrate the effectiveness of our approach thorough simulations in terms of performance parameters such as aggregate throughput, packet delivery ratio, end-to-end delay, and energy consumption
Implementation of Brand Positioning in an Effort to Become a Religious Tourist Destination: A Hubbul Wathan Grand Mosque Study
Islamic Center Masjid Raya Hubbul Wathan is the largest mosque and a religious tourism center in West Nusa Tenggara. This study examines the brand positioning strategy implemented by this mosque, which functions as both a grand mosque and a spiritual tourism center. This study uses a qualitative method with a case study approach. Data were collected by interview, observation, and documentation and tested by sources and techniques triangulation. The results show that this mosque, as the grand mosque, has numerous qualified national and international imams, magnificent and comprehensive congregational prayer facilities, and varied and high-quality Islamic studies as its differentiation. While in the category of religious tourism center, this mosque has the unique building architecture and Menara 99 icon as its main advantages. The results of this study can be a reference in the development of tourism mosques that are nowadays increasing in Indonesia