Relationship between the molecular composition, visible light absorption, and health-related properties of smoldering woodsmoke aerosols

Organic aerosols generated from the smoldering combustion of wood critically impact air quality and health for billions of people worldwide; yet, the links between the chemical components and the optical or biological effects of woodsmoke aerosol (WSA) are still poorly understood. In this work, an untargeted analysis of the molecular composition of smoldering WSA, generated in a controlled environment from nine types of heartwood fuels (African mahogany, birch, cherry, maple, pine, poplar, red oak, redwood, and walnut), identified several hundred compounds using gas chromatography mass spectrometry (GCMS) and nano-electrospray high-resolution mass spectrometry (HRMS) with tandem multistage mass spectrometry (MSn). The effects of WSA on cell toxicity as well as gene expression dependent on the aryl hydrocarbon receptor (AhR) and estrogen receptor (ER) were characterized with cellular assays, and the visible mass absorption coefficients (MACvis) of WSA were measured with ultraviolet-visible spectroscopy. The WSAs studied in this work have significant levels of biological and toxicological activity, with exposure levels in both an outdoor and indoor environment similar to or greater than those of other toxicants. A correlation between the HRMS molecular composition and aerosol properties found that phenolic compounds from the oxidative decomposition of lignin are the main drivers of aerosol effects, while the cellulose decomposition products play a secondary role; e.g., levoglucosan is anticorrelated with multiple effects. Polycyclic aromatic hydrocarbons (PAHs) are not expected to form at the combustion temperature in this work, nor were they observed above the detection limit; thus, biological and optical properties of the smoldering WSA are not attributed to PAHs. Syringyl compounds tend to correlate with cell toxicity, while the more conjugated molecules (including several compounds assigned to dimers) have higher AhR activity and MACvis. The negative correlation between cell toxicity and AhR activity suggests that the toxicity of smoldering WSA to cells is not mediated by the AhR. Both mass-normalized biological outcomes have a statistically significant dependence on the degree of combustion of the wood. In addition, our observations support the fact that the visible light absorption of WSA is at least partially due to charge transfer effects in aerosols, as previously suggested. Finally, MACvis has no correlation with toxicity or receptor signaling, suggesting that key chromophores in this work are not biologically active on the endpoints tested

PENERAPAN MODEL PEMBELAJARAN KOOPERATIF STUDENT TEAM ACHIEVEMENT DIVISONS UNTUK MENINGKATKAN HASIL BELAJAR SISWA DI MTS NEGERI 8 MUARO JAMBI

Penelitian ini bertujuan untuk meneliti penerapan Model Pembelajaran Kooperatif Student Team Achievement Divisons untuk meningkatkan hasil belajar siswa di MTs Negeri 8 Muaro Jambi. Penelitian ini merupakan penelitian tindak kelas (PTK) dengan menggunakan dua siklus. Instrumen pengumpulan data menggunakan lembar observasi dan soal. Berdasarkan pengumpulan data yang telah diperoleh, didapat adanya peningkatan presentase ketuntasan siswa dari siklus 1 46% dengan jumlah siswa yang berhasil mencapai KKM sekolah sebanyak 11 siswa dan nilai rata-rata kelas sebesar 69. Pada siklus II presentase ketuntasan siswa meningkat menjadi 86%, dengan jumlah siswa yang berhasil mencapai KKM sekolah sebanyak 24 siswa dan nilai rata-rata kelas mencapai 79. Dengan demikian model pembelajaran Student Teams Achivement Division dapat meningkatkan hasil belajar siswa di MTs Negeri 8 Muaro Jamb

PENGARUH PENGGUNAAN ALAT PERAGA MANIPULATIF TERHADAP MOTIVASI BELAJAR SISWA DI SEKOLAH MENENGAH ATAS NEGERI 16 KABUPATEN TEBO

Terhadap motivasi belajar siswa pada mata pelajaran biologi di Sekolah Menengah Atas Negeri 16 Kabupaten Tebo. Penelitian ini merupakan penelitian kuantitatif dengan menggunakan desain Quasi Experiment dengan the one group pretest-posttet design. Instrument pengumpulan data menggunakan angket (koesioner). Jumlah populasi sebanyak 1 kelas yaitu kelas XI IPA dan menjadi sampel kelas eksperimen adalah kelas XI IPA sebanyak 24 siswa. Hasil dari analisis data menunjukan bahwa nilai rata-rata sebelum diberikan perlakuan adalah sebesar 54,67 bermotivasi rendah dan nilai rata-rata sesudah diberikan perlakuan adalah sebesar 76,33 bermotivasi tinggi. Berdasarkan hasil pengumpulan data uji “t” dengan hasil yang diperoleh 5,54 lebih besar dari ttebel dari taraf signifikan 5% = 2,02 dan taraf signifikan 1% = 2,69, maka H0 ditolak dan Ha di terima. Hasil dari perhitungan effect size diperoleh besarnya effect size perlakuan yang diberikan adalah 1,18 atau 86%. Berdasarkan data tersebut menunjukkan bahwa terjadi pengaruh yang tinggi pada penggunaan alat peraga manipulatif terhadap motivasi belajar siswa Sekolah Menengah Atas Negeri 16 kabupaten Tebo. Hasil penelitian ini menyarankan agar guru untuk menggunakan, mengadakan alat peraga manipulatif guna perbaikan kualitas pembelajaran. Kata Kunci : Alat Peraga Manipulatif, Motivasi Belaja

PENERAPAN MODEL PEMBELAJARAN KOOPERATIF TIPE NUMBERED HEADS TOGETHERS (NHT) UNTUK MENINGKATKAN MOTIVASI BELAJAR SISWA DI MADRASAH ALIYAH NEGERI 3 KOTA JAMBI

Penelitian ini bertujuan untuk meningkatkan motivasi belajar siswa kelas X MIPA 2 melalui penerapan model pembelajaran kooperatif tipe Numbered Heads Togethers (NHT). Metode penelitian yang digunakan adalah Penelitian Tindakan Kelas (PTK), dengan langkah-langkah perencanaan, pelaksanaan, observasi dan refleksi. Berdasarkan hasil penilaian angket siswa pada pra tindakan menunjukkan bahwa presentase yang di dapat sebesar 59% yang tergolong sedang, namun masih kurang termotivasi. Lalu pada siklus I terjadi peningkatan presentase penilaian angket motivasi belajar siswa sebesar 9% menjadi 68% yang cukup tinggi, namun masih belum memenuhi target peneliti. Dan pada akhir siklus II terjadi peningkatan presentase penilaian angket motivasi belajar siswa sebesar 13% menjadi 81% yang menandakan presentase penilaian motivasi belajar siswa telah mencapai target yang diinginkan yaitu pada interval sangat tinggi. Dengan hasil penilaian angket motivasi belajar tersebut maka dapat disimpulkan bahwa penerapan pembelajaran kooperatif tipe Number Head Together (NHT) mampu meningkatkan motivasi belajar siswa pada mata pelajaran Biologi siswa kelas X MIPA 2 Madrasah Aliyah Negeri 3 Kota Jambi

A Decline in New HIV Infections in South Africa: Estimating HIV Incidence from Three National HIV Surveys in 2002, 2005 and 2008

Three national HIV household surveys were conducted in South Africa, in 2002, 2005 and 2008. A novelty of the 2008 survey was the addition of serological testing to ascertain antiretroviral treatment (ART) use.We used a validated mathematical method to estimate the rate of new HIV infections (HIV incidence) in South Africa using nationally representative HIV prevalence data collected in 2002, 2005 and 2008. The observed HIV prevalence levels in 2008 were adjusted for the effect of antiretroviral treatment on survival. The estimated "excess" HIV prevalence due to ART in 2008 was highest among women 25 years and older and among men 30 years and older. In the period 2002-2005, the HIV incidence rate among men and women aged 15-49 years was estimated to be 2.0 new infections each year per 100 susceptible individuals (/100pyar) (uncertainty range: 1.2-3.0/100pyar). The highest incidence rate was among 15-24 year-old women, at 5.5/100pyar (4.5-6.5). In the period 2005-2008, incidence among men and women aged 15-49 was estimated to be 1.3/100 (0.6-2.5/100pyar), although the change from 2002-2005 was not statistically significant. However, the incidence rate among young women aged 15-24 declined by 60% in the same period, to 2.2/100pyar, and this change was statistically significant. There is evidence from the surveys of significant increases in condom use and awareness of HIV status, especially among youth.Our analysis demonstrates how serial measures of HIV prevalence obtained in population-based surveys can be used to estimate national HIV incidence rates. We also show the need to determine the impact of ART on observed HIV prevalence levels. The estimation of HIV incidence and ART exposure is crucial to disentangle the concurrent impact of prevention and treatment programs on HIV prevalence

HIV-positive status disclosure in patients in care in rural South Africa: implications for scaling up treatment and prevention interventions.

CAPRISA, 2015Abstract available in pdf

Improving the prevention, diagnosis and treatment of TB among people living with HIV: the role of operational research

Operational research is necessary to improve the access to and delivery of tuberculosis prevention, diagnosis and treatment interventions for people living with HIV. We conducted an extensive review of the literature and reports from recent expert consultations and research-related meetings organized by the World Health Organization and the Stop TB Partnership to identify a TB/HIV operational research agenda. We present critical operational research questions in a series of key areas: optimizing TB prevention by enhancing the uptake of isoniazid preventive therapy and the implementation of infection control measures; assessing the effectiveness of existing diagnostic tools and scaling up new technologies; improving service delivery models; and reducing risk factors for mortality among TB patients living with HIV. We discuss the potential impact that addressing the operational research questions may have on improving programmes’ performance, assessing new strategies or interventions for TB control, or informing global or national policy formulation. Financial resources to implement these operational research questions should be mobilized from existing and new funding mechanisms. National TB and HIV/AIDS programmes should develop their operational research agendas based on these questions, and conduct the research that they consider crucial for improving TB and HIV control in their settings in collaboration with research stakeholders

The whole is greater than the sum of the parts: Recognising missed opportunities for an optimal response to the rapidly maturing TB-HIV co-epidemic in South Africa

<p>Abstract</p> <p>Background</p> <p>Despite widely acknowledged WHO guidelines for the integration of TB and HIV services, heavily burdened countries have been slow to implement these and thus significant missed opportunities have arisen.</p> <p>Discussion</p> <p>The individual-centred, rights-based paradigm of the SA National AIDS Policy, remains dissonant with the compelling public-health approach of TB control. The existence of independent and disconnected TB and HIV services results in a wastage of scarce health resources, an increased burden on patients' time and finances, and ignores evidence of patients' preference for an integrated service. The current situation translates into a web of unacceptable, ongoing missed opportunities such as failure to maximize collaborative disease surveillance, VCT, adherence support, infection control, and positive prevention. TB services present a readily identifiable cohort for HIV provider-initiated testing. Integrating HAART and DOTS will promote efficient usage of health workers' time and a more navigable experience for patients, ultimately ensuring increased TB treatment completion rates and MDR-TB prevention. As direct observation evolves into a more supportive, empowering experience for patients, adherence to both TB drugs and HAART will be bolstered. Little attention has been paid to the transmission of TB within HIV services. Low cost infection control interventions include: triaging patients, scheduling new and follow-up patients separately; well-ventilated, sheltered waiting rooms; and the use of personal respirators by patients and staff. A more patient-centred approach to TB care may be able to recruit the active participation of TB patients in positive prevention efforts, including maximizing personal infection control, limiting exposure of social contacts to TB during the intensive phase of treatment, advocating isoniazid prophylaxis within the home and patient-centred education efforts to reduce overall transmission. Several model programmes demonstrated synergy, in which the impact of the "whole" or integrated response was greater than the sum of the non-integrated parts.</p> <p>Summary</p> <p>The full potential of an integrated TB-HIV service has not been fully harvested. Missed opportunities discount existing efforts in both programmes, will perpetuate the burden of disease, and prevent major gains in future interventions. This paper outlines simple, readily-implementable strategies to narrow the gap and reclaim existing missed opportunities.</p

HIV Incidence among Men Who Have Sex with Men in China: A Meta-Analysis of Published Studies

Men who have sex with men (MSM) have now become one of the priority populations for prevention and control of HIV pandemic in China. Information of HIV incidence among MSM is important to describe the spreading of the infection and predict its trends in this population. We reviewed the published literature on the incidence of HIV infection among MSM in China.We identified relevant studies by use of a comprehensive strategy including searches of Medline and two Chinese electronic publication databases from January 2005 to September 2010. Point estimate of random effects incidence with corresponding 95% confidence intervals (CI) of HIV infection was carried out using the Comprehensive Meta-Analysis software. Subgroup analyses were examined separately, stratified by study design and geographic location.Twelve studies were identified, including three cohort studies and nine cross-sectional studies. The subgroup analyses revealed that the sub-overall incidence estimates were 3.5% (95% CI, 1.7%-5.3%) and 6.7% (95% CI, 4.8%-8.6%) for cohort and cross-sectional studies, respectively (difference between the sub-overalls, Q = 5.54, p = 0.02); and 8.3% (95% CI, 6.9%-9.7%) and 4.6% (95% CI, 2.4%-6.9%) for studies in Chongqing and other areas, respectively (difference between the sub-overalls, Q = 7.58, p<0.01). Syphilis infection (RR = 3.33, p<0.001), multiple sex partnerships (RR = 2.81, p<0.001), and unprotected receptive anal intercourse in the past six months (RR = 3.88, p = 0.007) represented significant risk for HIV seroconversion.Findings from this meta-analysis indicate that HIV incidence is substantial in MSM in China. High incidence of HIV infection and unique patterns of sexual risk behaviors in this population serve as a call for action that should be answered with the innovative social and public health intervention strategies, and development of biological prevention strategies