Eccentric connectivity index of some chemical trees

Let G = (V, E) be a simple connected molecular graph. In such a simple molecular graph, vertices represent atoms and edges represent chemical bonds, we denoted the sets of vertices and edges by V(G) and E(G), respectively. If d(u, v) be the notation of distance between vertices u, v ε V(G) and is defined as the length of a shortest path connecting them. Then, the eccentricity connectivity index of a molecular graph G is defined as ζ(G) = Σ vεv(G) deg(v)ec(v), where deg(v) is degree of a vertex v ε V(G), and is defined as the number of adjacent vertices with v. ec(v) is eccentricity of a vertex v ε V(G), and is defined as the length of a maximal path connecting to another vertex of v. In this paper, we establish the general formulas for the eccentricity connectivity index of some classes of chemical trees

Traditional and Complementary Medicine (T&CM) use and its association with diabetic control among diabetic patients in a tertiary Centre, Kuantan Pahang

INTRODUCTION: Diabetes mellitus is a major global health concern worldwide. The fact that it is a lifelong chronic illness contributes to the increasing tendency of seeking traditional and complementary medicine (T&CM), yet study regarding this remains limited. This study aimed to measure the prevalence of T&CM use among diabetic patients and its association with diabetic control. MATERIALS AND METHODS: A cross sectional study was conducted at Hospital Tengku Ampuan Afzan (HTAA), Kuantan between July and August 2018. Following written consent, 136 type 2 adult diabetic patients in medical ward and those attending diabetic clinic were interviewed regarding the use of T & CM; and their blood investigation results were collected from patients' medical records. A data collection form was used as study instrument. Descriptive statistic was used to measure the prevalence while chi-square test and independent t-test were used to find associations between T&CM use and study background and diabetic control. RESULTS: Low prevalence of T&CM use (16.9%) was found, predominated by retiree group (p<0.05). Majority of patients used T&CM as additional treatment for diabetes (60.9%) and the usage was influenced by friends, family members and advertisement. There was a significant difference in Glycosylated haemoglobin A1c (HbA1c) and Estimated Glomerular Filtration Rate (eGFR) levels between inpatient and outpatient T&CM users (p<0.05). CONCLUSION: 1 in every 6 diabetic patients in HTAA, Kuantan were using T&CM along with conventional diabetic medications in which retirees are predominated. No associations were found between T&CM uses and diabetic control. Outpatient T&CM users had lower HbA1c level with higher eGFR compared to inpatient users

Synergistic enhancement in the microelectronic properties of poly-(dioctylfluorene) based Schottky devices by CdSe quantum dots

This paper reports the potential application of cadmium selenide (CdSe) quantum dots (QDs) in improving the microelectronic characteristics of Schottky barrier diode (SBD) prepared from a semiconducting material poly-(9,9-dioctylfluorene) (F8). Two SBDs, Ag/F8/P3HT/ITO and Ag/F8-CdSe QDs/P3HT/ITO, are fabricated by spin coating a 10 wt% solution of F8 in chloroform and 10:1 wt% solution of F8:CdSe QDs, respectively, on a pre-deposited poly(3-hexylthiophene) (P3HT) on indium tin oxide (ITO) substrate. To study the electronic properties of the fabricated devices, current-voltage (I-V) measurements are carried out at 25 °C in dark conditions. The I-V curves of Ag/F8/P3HT/ITO and Ag/F8-CdSe QDs/P3HT/ITO SBDs demonstrate asymmetrical behavior with forward bias current rectification ratio (RR) of 7.42 ± 0.02 and 142 ± 0.02, respectively, at ± 3.5 V which confirm the formation of depletion region. Other key parameters which govern microelectronic properties of the fabricated devices such as charge carrier mobility (µ), barrier height (ϕ ), series resistance (R ) and quality factor (n) are extracted from their corresponding I-V characteristics. Norde's and Cheung functions are also applied to characterize the devices to study consistency in various parameters. Significant improvement is found in the values of R , n, and RR by 3, 1.7, and 19 times, respectively, for Ag/F8-CdSe QDs/P3HT/ITO SBD as compared to Ag/F8/P3HT/ITO. This enhancement is due to the incorporation of CdSe QDs having 3-dimensional quantum confinement and large surface-to-volume area. Poole-Frenkle and Richardson-Schottky conduction mechanisms are also discussed for both of the devices. Morphology, optical bandgap (1.88 ± 0.5 eV) and photoluminescence (PL) spectrum of CdSe QDs with a peak intensity at 556 nm are also reported and discussed

Prestasi pembakaran biodiesel berasaskan minyak bunga matahari ke atas pembakar berbahan api cecair

Kajian ini menyiasat mengenai prestasi pembakaran adunan bahan api biodiesel berasaskan minyak bunga matahari dengan diesel pada nisbah B10 (biodiesel 10%, diesel 90%), B15 (biodiesel 15%, diesel 85%), B25 (biodiesel 25%, diesel 75%) dan B50 (biodiesel 50%, diesel 50%). Prestasi pembakaran bahan api ini dinilai berdasarkan kepada nilai suhu dinding kebuk pembakar, kecekapan terma pembakar serta kepekatan gas emisi yang dibebaskan seperti oksida nitrogen (NOx), sulfur dioksida (SO2), dan karbon monoksida (CO). Bahan api adunan biodiesel berasaskan minyak bunga matahari diukur dan dibandingkan dengan diesel. Semua bahan api yang diuji dibakar menggunakan kebuk pembakaran terbuka pada lima nisbah kesetaraan yang berbeza, iaitu, keadaan cair bahan api (Ф = 0.8 dan 0.9), stoikiometri (Ф = 1.0), dan kaya bahan api (Ф = 1.1 dan 1.2). Hasil kajian menunjukkan bahawa bahan api biodiesel berasaskan minyak bunga matahari terbakar pada suhu yang lebih rendah. Ini menghasilkan tenaga terma bahan api dan kecekapan terma pembakar yang lebih rendah dari diesel. Selain itu, emisi yang dihasilkan adalah lebih rendah (kecuali NOx) berbanding dengan diesel untuk semua nisbah kesetaraan. Hasilnya juga menunjukkan bahawa penggunaan biodiesel adalah berguna untuk aplikasi moden yang berbeza, khususnya di sektor industri kerana ia lebih mesra alam dan boleh dijadikan sebagai pilihan alternatif kepada bahan api petroleum. The current study investigated the combustion performance of sunflower oil-based biodiesel fuel blends with diesel at the ratio of B10 (10% biodiesel, 90% diesel), B15 (15% biodiesel, 85% diesel), B25 (25% biodiesel, 75% diesel) and B50 (50% biodiesel, 50% diesel). The combustion performance of this fuel is evaluated based on the value of the combustion chamber wall temperature, the thermal efficiency of the burner as well as the concentration of emission gases released such as nitrogen oxides (NOx), sulfur dioxide (SO2), and carbon monoxide (CO). Sunflower oil-based biodiesel blend fuel was measured and compared to diesel. All fuels tested were burned using a combustion chamber with one of its ends open, at five different equivalence ratios, namely, fuellean condition (Ф = 0.8 and 0.9), stoichiometry (Ф = 1.0), and fuel-rich (Ф = 1.1 and 1.2). The results show that sunflower oil-based biodiesel fuels burn at lower temperatures. This results in lower fuel thermal energy, and thus, lower thermal efficiency of the burner compared to diesel. Moreover, the emissions produced are lower (except for NOx) compared to diesel for all equivalence ratios. The results also show that the use of biodiesel is useful for different modern applications, especially in the industrial sector as it is more environmentally friendly and can be used as an alternative to petroleum fuels

Experimental investigation of energy storage properties and thermal conductivity of a novel organic phase change material/MXene as A new class of nanocomposites

Energy storage is a global critical issue and important area of research as most of the renewable sources of energy are intermittent. In this research work, recently emerged inorganic nanomaterial (MXene) is used for the first time with paraffin wax as a phase change material (PCM) to improve its thermo-physical properties. This paper focuses on preparation, characterization, thermal properties and thermal stability of new class of nanocomposites induced with MXene nanoparticles in three different concentrations. Acquired absorbance (UV-Vis) for nanocomposite with loading concentration of 0.3 wt.% of MXene achieved ~39% enhancement in comparison with the pure paraffin wax. Thermal conductivity measurement for nanocomposites in a solid state is performed using a KD2 PRO decagon. The specific heat capacity (cp) of PCM based MXene is improved by introducing MXene. The improvement of cp is found to be 43% with 0.3 wt.% of MXene loaded in PCM. The highest thermal conductivity increment is found to be 16% at 0.3 wt.% concentration of MXene in PCM. Decomposition temperature of this new class of nanocomposite with 0.3 wt.% mass fraction is increased by ~6%. This improvement is beneficial in thermal energy storage and heat transfer applications

Population Health Metrics Research Consortium gold standard verbal autopsy validation study: design, implementation, and development of analysis datasets

Background: Verbal autopsy methods are critically important for evaluating the leading causes of death in populations without adequate vital registration systems. With a myriad of analytical and data collection approaches, it is essential to create a high quality validation dataset from different populations to evaluate comparative method performance and make recommendations for future verbal autopsy implementation. This study was undertaken to compile a set of strictly defined gold standard deaths for which verbal autopsies were collected to validate the accuracy of different methods of verbal autopsy cause of death assignment.Methods: Data collection was implemented in six sites in four countries: Andhra Pradesh, India; Bohol, Philippines; Dar es Salaam, Tanzania; Mexico City, Mexico; Pemba Island, Tanzania; and Uttar Pradesh, India. The Population Health Metrics Research Consortium (PHMRC) developed stringent diagnostic criteria including laboratory, pathology, and medical imaging findings to identify gold standard deaths in health facilities as well as an enhanced verbal autopsy instrument based on World Health Organization (WHO) standards. A cause list was constructed based on the WHO Global Burden of Disease estimates of the leading causes of death, potential to identify unique signs and symptoms, and the likely existence of sufficient medical technology to ascertain gold standard cases. Blinded verbal autopsies were collected on all gold standard deaths.Results: Over 12,000 verbal autopsies on deaths with gold standard diagnoses were collected (7,836 adults, 2,075 children, 1,629 neonates, and 1,002 stillbirths). Difficulties in finding sufficient cases to meet gold standard criteria as well as problems with misclassification for certain causes meant that the target list of causes for analysis was reduced to 34 for adults, 21 for children, and 10 for neonates, excluding stillbirths. To ensure strict independence for the validation of methods and assessment of comparative performance, 500 test-train datasets were created from the universe of cases, covering a range of cause-specific compositions.Conclusions: This unique, robust validation dataset will allow scholars to evaluate the performance of different verbal autopsy analytic methods as well as instrument design. This dataset can be used to inform the implementation of verbal autopsies to more reliably ascertain cause of death in national health information systems

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks