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Marine litter is increasingly recognised as a vector for the spread of non-native species (NNS). However, our understanding of its role in the propagation of NNS in UK waters remains limited. As part of the Clean Seas Environmental Monitoring Programme, we opportunistically analysed seafloor macrolitter items trawled from various locations around the coast of England and Wales and examined each for the presence of NNS. Of the 41 litter items analysed, we identified a total of 133 taxa, including two non-native and four cryptogenic species. This confirms that NNS are settling on seafloor macrolitter in UK waters and that these can be detected using morphological taxonomic analysis. Furthermore, we propose a methodology to classify litter based on size, rugosity and polymer/material type to explore whether there were detectable patterns governing community composition and litter characteristics. This exploratory investigation provides evidence to inform future risk assessments of NNS vectors and pathways.
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Monitoramento Ambiental , Espécies Introduzidas , Monitoramento Ambiental/métodos , Animais , Reino Unido , Inglaterra , País de GalesRESUMO
To inform risk assessments, reliable, time efficient and affordable quantification methods are required for creating a microplastic (MP) pollution baseline in the world's oceans. To facilitate this, MP abundance was investigated in sediments of three contrasting areas of the UK continental shelf: North West of Jones Bank, the Canyons in the Celtic Sea and Dogger Bank in the North Sea, utilising the Nile Red tagging method to assess its time efficiency and cost. Average MP abundance in the top 10 cm was 1050-2700 MP kg-1. MP abundance decreased with increasing sediment depth and increased with increasing water depth. The findings emphasise the extent of MP pollution and illustrate the value of Nile Red for large scale mapping at relatively low cost.
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Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Plásticos , Reino Unido , Poluentes Químicos da Água/análiseRESUMO
The lyotropic phase behavior of four common and easily accessible glycosides, n-octyl α-d-glycosides, namely, α-Glc-OC8, α-Man-OC8, α-Gal-OC8, and α-Xyl-OC8, was investigated. The presence of normal hexagonal (HI), bicontinuous cubic (VI), and lamellar (Lα) phases in α-Glc-OC8 and α-Man-OC8 including their phase diagrams in water reported previously was verified by deuterium nuclear magnetic resonance (2H NMR), via monitoring the D2O spectra. Additionally, the partial binary phase diagrams and the liquid crystal structures formed by α-Gal-OC8 and α-Xyl-OC8 in D2O were constructed and confirmed using small- and wide-angle X-ray scattering and 2H NMR. The average number of bound water molecules (nb) per headgroup in the Lα phase was determined by the systematic measurement of the quadrupolar splitting of D2O over a wide range of molar ratio values (glycoside/D2O), especially at high glucoside composition. The number of bound water molecules bound to the headgroup was found to be around 1.5-2.0 for glucoside, mannoside, and galactoside, all of which possesses four OH groups. In the case of xyloside, which has only three OH groups, the bound water content is â¼2.0. Our findings confirmed that the bound water content of all n-octyl α-d-glycosides studied is lower compared to the number of possible hydrogen bonding sites possibly due to the fact that most of the OH groups are involved in intralayer interaction that holds the lipid assembly together.
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OBJECTIVE: To demonstrate whether there is an association between jugular venous reflux and nonpulsatile subjective tinnitus (NST) using real-time four-dimensional magnetic resonance imaging (MRI) angiography. MATERIALS AND METHODS: Patients with unilateral NST who underwent contrast-enhanced MRI with a special protocol were included in the study. Thick slab dynamic maximum intensity projection images were obtained including interleaved stochastic trajectories (TWIST)-MRI examination. All patients were requested to perform Valsalva maneuver during the sequence. Jugular venous reflux grading was performed as follows: absence of reflux or if reflux does not reach the base of the skull: grade 0; if reflux reaches the jugular bulb, but no intracranial contrast is observed: grade 1; and if reflux extends into the intracranial cortical veins and/or the cavernous sinus above the jugular bulb: Grade 2. RESULTS: A total number of 30 patients, 23 male and 7 female, were included in the study. Jugular venous reflux was not identified (Grade 0) in 20 patients. Grade 1 reflux was determined in 7 cases and Grade 2 reflux was observed in 3 cases. Notably, only patients with Grade 2 reflux described worsening of their tinnitus symptoms during the examination and their daily activities as well. CONCLUSIONS: NST might also be associated with hemodynamic problems of the venous system and the MRI protocol starting with TWIST accompanied with Valsalva maneuver is not well-known, yet seems to be a feasible and beneficial method to detect potential jugular venous reflux in NST patients.
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Encéfalo/irrigação sanguínea , Veias Jugulares/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Zumbido/etiologia , Insuficiência Venosa/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Veias Jugulares/patologia , Masculino , Pessoa de Meia-Idade , Zumbido/fisiopatologia , Manobra de Valsalva , Insuficiência Venosa/complicações , Adulto JovemRESUMO
Seeking regulatory and ethical approval is a significant task that must be completed before conducting a clinical trial of a medical device. Currently in the UK, the Integrated Research Application System (IRAS) is a unified system for preparing regulatory, ethical and governance applications for the relevant bodies that must approve health and social research. This article outlines key aspects in planning a clinical trial of a medical device and how applications for approval can be prepared using IRAS.
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Ensaios Clínicos como Assunto , Equipamentos e Provisões , Reino UnidoRESUMO
We report on the development of a simple-architecture fiber-based frequency distribution system used to transfer high frequency stability 100 MHz signals. This work is focused on the emitter and the receiver performances that allow the transmission of the radio-frequency signal over an optical fiber. The system exhibits a residual fractional frequency stability of 1 × 10-14 at 1 s integration time and in the low 10-16 range after 100 s. These performances are suitable to transfer the signal of frequency references such as those of a state-of-the-art hydrogen maser without any phase noise compensation scheme. As an application, we demonstrate the dissemination of such a signal through a 100 m long optical fiber without any degradation. The proposed setup could be easily extended for operating frequencies in the 10 MHz-1 GHz range.
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The synthesis and characterisation of the nonsymmetric liquid crystal dimer, 1-(4-cyanobiphenyl-4'-yloxy)-6-(4-cyanobiphenyl-4'-yl)hexane (CB6OCB) is reported. An enantiotropic nematic (N)-twist-bend nematic (NTB) phase transition is observed at 109 °C and a nematic-isotropic phase transition at 153 °C. The NTB phase assignment has been confirmed using polarised light microscopy, freeze fracture transmission electron microscopy (FFTEM), (2)H-NMR spectroscopy, and X-ray diffraction. The effective molecular length in both the NTB and N phases indicates a locally intercalated arrangement of the molecules, and the helicoidal pitch length in the NTB phase is estimated to be 8.9 nm. The surface anchoring properties of CB6OCB on a number of aligning layers is reported. A Landau model is applied to describe high-resolution heat capacity measurements in the vicinity of the NTB-N phase transition. Both the theory and heat capacity measurements agree with a very weak first-order phase transition. A complementary extended molecular field theory was found to be in suggestive accord with the (2)H-NMR studies of CB6OCB-d2, and those already known for CB7CB-d4. These include the reduced transition temperature, TNTBN/TNI, the order parameter of the mesogenic arms in the N phase close to the NTB-N transition, and the order parameter with respect to the helix axis which is related to the conical angle for the NTB phase.
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BACKGROUND: The association between depression, anxiety, and stress among Arab menopause and postmenopausal women have been explored in detailed. AIM: The objective of this study was to determine the correlation between depression, anxiety, and stress in menopausal and postmenopausal women and shedding more light on a complex relationship. SUBJECTS AND METHODS: A cross-sectional descriptive study was used to generate menopause symptoms experienced by Arabian women at the primary health care centers in Qatar. A representative sample of 1468 women aged 45-65 years were approached during July 2012 and May 2014 and 1101 women agreed to participate (75.0%) and responded to the study. Depression, anxiety, and stress were measured using the Depression Anxiety Stress Scales 21. Data on body mass index (BMI), clinical and other parameters were used. Univariate, multivariate, and matrix correlation analysis were performed for statistical analysis. RESULTS: A total of 1101 women agreed to participate after informed consent was obtained. The mean age and standard deviation (SD) of the menopausal age were 49.55 (3.12), the mean and SD of postmenopausal age was 58.08 (3.26) (P < 0.001). There were statistically significant differences between menopausal stages with regards to age, ethnicity, educational status, occupation status, and place of living. Furthermore, there were statistically significant differences between menopausal stages with regards to BMI, systolic and diastolic blood pressure (BP), Vitamin D deficiency, and diseases. Depression and anxiety were more common among postmenopause women. Furthermore, there were no differences between the groups regarding the frequency of certain levels of stress among menopause and postmenopause. The multivariate regression analyses revealed that age in years, diastolic BP, consanguinity, regular exercise were a predictor for depression. Meanwhile, diastolic BP, occupation, and physical activity considered the main risk factors for anxiety. Furthermore, age in years, occupation, and sheesha smoking habits were considered as the main risk factors associated with stress. CONCLUSION: A large number of factors were associated with experiencing menopausal and psycho-social problems and which had negative effects on the quality of life among Arabian women. Depression, anxiety, and stress should be considered as important risk factors for osteoporosis.
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Wolcott-Rallison Syndrome (WRS), also known as Multiple Epiphyseal Dysplasia with Early-onset Diabetes Mellitus is a rare autosomal recessive multisystemic disorder. Its characteristic clinical features are permanent neonatal or early infancy insulin-dependent diabetes and later onset skeletal dysplasia. Other frequent clinical manifestations are hepatic and renal dysfunction, mental retardation, cardiac abnormalities, exocrine pancreatic dysfunction, primary hypothyroidism and neutropenia. This report presents an 8-year-old WRS case who is found to have W522X mutation in EIF2AK3 gene which was only found in two other unrelated Turkish families. W522X mutation in EIF2AK3 gene seems to be confined to Turkey and may be a common mutation in WRS patients from this country. In this paper, we evaluate the clinical features of the patients having W522X mutation and we compare this group with other patients reported to date. Except the characteristic features as diabetes mellitus and epiphyseal dysplasia, all the WRS patients, including patients with W522X mutation, show extensive phenotypic variability that correlates poorly to genotype which suggests that there is no correlation between a specific mutation and the clinical manifestation.
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Análise Mutacional de DNA , Diabetes Mellitus Tipo 1/genética , Epífises/anormalidades , Genótipo , Osteocondrodisplasias/genética , Fenótipo , eIF-2 Quinase/genética , Criança , Aberrações Cromossômicas , Códon sem Sentido/genética , Consanguinidade , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Genes Recessivos , Homozigoto , Humanos , Íntrons/genética , Osteocondrodisplasias/diagnóstico , Análise de Sequência de DNA , TurquiaAssuntos
Segregação de Cromossomos/genética , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 21/genética , Síndrome de Down/genética , Translocação Genética/genética , Análise Citogenética , Feminino , Triagem de Portadores Genéticos , Aconselhamento Genético , Humanos , Lactente , Cariotipagem , Diagnóstico Pré-NatalRESUMO
The dynamic alignment of the nematic director by near-orthogonal electric and magnetic fields has been investigated. The intermediate states during the relaxation process were found, with the aid of time-resolved deuterium NMR spectroscopy, to be markedly nonuniform. The macroscopic order was perturbed, although the initial and final states of the director appear to be essentially uniform. However, the initial state does have a profound influence on the uniformity of the director in the intermediate states. We have developed a fundamental model based on the effect of spontaneous director fluctuations to explain these unusual NMR observations.
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The nature of the nematic-nematic phase transition in the liquid crystal dimer 1â³,9â³-bis(4-cyanobiphenyl-4'-yl) nonane (CB9CB) has been investigated using techniques of calorimetry, dynamic dielectric response measurements, and (2)H NMR spectroscopy. The experimental results for CB9CB show that, like the shorter homologue CB7CB, the studied material exhibits a normal nematic phase, which on cooling undergoes a transition to the twist-bend nematic phase (N(TB)), a uniaxial nematic phase, promoted by the average bent molecular shape, in which the director tilts and precesses describing a conical helix. Modulated differential scanning calorimetry has been used to analyze the nature of the N(TB)-N phase transition, which is found to be weakly first order, but close to tricritical. Additionally broadband dielectric spectroscopy and (2)H magnetic resonance studies have revealed information on the structural characteristics of the recently discovered twist-bend nematic phase. Analysis of the dynamic dielectric response in both nematic phases has provided an estimate of the conical angle of the heliconical structure for the N(TB) phase. Capacitance measurements of the electric-field realignment of the director in initially planar aligned cells have yielded values for the splay and bend elastic constants in the high temperature nematic phase. The bend elastic constant is small and decreases with decreasing temperature as the twist-bend phase is approached. This behavior is expected theoretically and has been observed in materials that form the twist-bend nematic phase. (2)H NMR measurements characterize the chiral helical twist identified in the twist-bend nematic phase and also allow the determination of the temperature dependence of the conical angle and the orientational order parameter with respect to the director.
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We have investigated the phase behavior of four glycosides (ßC8OGlc, ßC8SGlc, ßC10OGlc, ßC8OGal) in water and D2O by optical polarizing microscopy and deuterium NMR. Previously published phase diagrams were evaluated by deuterium NMR, via monitoring D2O spectra, and confirmed the presence of the hexagonal, bicontinuous cubic, and lamellar phases in these glycosides. We have also shown the presence of the gel phase in (ßC10OGlc) and observed the extensive supercooling of the lamellar phase to temperatures well below the Kraft line. While the main features of the phase diagrams were confirmed, some phase boundaries were found to be slightly different. Magnetically aligned spectra were also observed for relatively dilute samples for the hexagonal phase (ßC8OGlc and ßC8OGal) and the lamellar phase (ßC8SGlc and ßC10OGlc). The average number of bound water molecules per headgroup in the lamellar phase for the glycosides was determined by the systematic measurement of the quadrupolar splitting of D2O over a wide range of values of the (glycoside/water) molar ratio. The number of water molecules bound to the headgroup was found on average to be about 1.6-1.7 water molecules with no significant differences in this value for the different glycosides (and over the temperature range investigated), indicating that the bound water content is predominately influenced by the number of hydroxyl groups of the headgroup only. However, this bound water content of only 1.6-1.7 water molecules per sugar headgroup is surprisingly low, suggesting strong intermolecular interactions of the OH groups of headgroup sugars. The results are in line with computational results reported earlier for the octyl-ß-glucoside and ß-galactoside, which show the presence of strong intralayer hydrogen bonding.
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Óxido de Deutério/química , Deutério/química , Glicosídeos/química , Cristais Líquidos/química , Espectroscopia de Ressonância Magnética , Microscopia de PolarizaçãoRESUMO
Scaffolds have been utilized in tissue regeneration to facilitate the formation and maturation of new tissues or organs where a balance between temporary mechanical support and mass transport (degradation and cell growth) is ideally achieved. Polymers have been widely chosen as tissue scaffolding material having a good combination of biodegradability, biocompatibility, and porous structure. Metals that can degrade in physiological environment, namely, biodegradable metals, are proposed as potential materials for hard tissue scaffolding where biodegradable polymers are often considered as having poor mechanical properties. Biodegradable metal scaffolds have showed interesting mechanical property that was close to that of human bone with tailored degradation behaviour. The current promising fabrication technique for making scaffolds, such as computation-aided solid free-form method, can be easily applied to metals. With further optimization in topologically ordered porosity design exploiting material property and fabrication technique, porous biodegradable metals could be the potential materials for making hard tissue scaffolds.
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One of the defining characteristics of the twist-bend nematic phase, formed by the methylene-linked liquid crystal dimer 1â³,7â³-bis(4-cyanobiphenyl-4'-yl) heptane (CB7CB), is its chirality. This new nematic phase, predicted by Dozov, is of particular interest because although the constituent molecules are achiral the phase itself is chiral. Here, we describe the use of NMR spectroscopy to determine experimentally whether in reality the phase is chiral or not. The basis of this novel procedure is that the equivalence of the protons or deuterons in a prochiral methylene group in a nematic phase with D∞h symmetry is lost in a chiral phase because its symmetry is reduced to D∞ on removal of the mirror plane. Recording proton-enhanced local field (PELF) NMR experiments shows that in the standard nematic phase all of the methylene groups in the heptane spacer have equivalent pairs of C-H groups but this equivalence is lost for the six prochiral methylene groups with their enantiotopic protons on passing to the twist-bend nematic. Strikingly, this equivalence is not lost for the central methylene group where the two protons are homotopic. We also show how the phase chirality can be demonstrated with probe molecules which contain deuteriated prochiral methylene groups, using 4-octyl-4'-cyanobiphenyl-d2, perdeuteroacenaphthene-d10, and acenaphthene-d4 as examples. For the standard nematic phase deuterium, NMR shows that the deuterons in these methylene groups are equivalent but, as expected, in the twist-bend nematic phase this equivalence is lost. The deuterium NMR spectra of these probe molecules dissolved in CB7CB have been recorded from the isotropic phase, through the nematic and deep into the supercooled twist-bend nematic.
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Compostos de Bifenilo/química , Heptanos/química , Cristais Líquidos/química , Deutério/química , Espectroscopia de Ressonância MagnéticaRESUMO
INTRODUCTION: Salivary-glands tumors come in various presentations and the epidemiological data are variable. The aim of this retrospective study was to establish an epidemiological profile of salivary-glands tumors in a Tunisian teaching hospital and to compare it to published data. PATIENTS AND METHODS: The study was made on 76 men and 80 women with a mean age of 43 years (five months to 85 years). Sixty percent of the tumors were parotid lesions, 16% were submandibular and 24% located on minor salivary glands. Eighty-four percent of parotid tumors were benign. Malignant-parotid tumors often affected men over 60 years of age. Most minor salivary-glands tumors were located on the palate. DISCUSSION: Benign salivary-glands tumors, often have a parotid localization affect, more women in the Tunisian population. Contrary to the literature, in our series, malignant tumors were predominant in women.
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Neoplasias das Glândulas Salivares/epidemiologia , Adenoma Pleomorfo/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoide Cístico/epidemiologia , Carcinoma Mucoepidermoide/epidemiologia , Criança , Pré-Escolar , Estudos Epidemiológicos , Feminino , Hospitais de Ensino/estatística & dados numéricos , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias Parotídeas/epidemiologia , Estudos Retrospectivos , Glândulas Salivares Menores/patologia , Fatores Sexuais , Neoplasias da Glândula Submandibular/epidemiologia , Tunísia/epidemiologiaRESUMO
Anterior cervical discectomy with or without fusion has been commonly used for cervical disc disease since the description by Smith and Robinson in 1958. In this report, surgical technique, advantages, and disadvantages of the posterior approach, known as the posterior keyhole laminotomy-foraminotomy, are reviewed and motion versus fusion surgery discussed. Between 1996 and 2004, the keyhole laminotomy-foraminotomy was performed on 84 patients suffering from lateral cervical soft disc herniation or osteophytes. All the procedures were performed under the surgical microscope. A high-speed drill was used for drilling the bone. In 49 patients (58%), soft disc herniation was removed, while in 35 patients (42%) there were osteophytes. Successful relief of radiculopathy symptoms was achieved in 80 patients (96%). In 4 patients the symptoms recurred. One patient (1.2%) developed kyphosis. The only complication observed intraoperatively was a partial root injury in one patient (1.2%). Mean hospitalization time was 48 hours. The posterior approach is particularly appropriate in patients whose root compression is located posterolaterally. Advantages of this surgery are minimal lamina resection, good visualization of the nerve root, postoperative early mobilization and minimal hospitalization. Microsurgery enables us to both preserve the motion of operated segment and avoid cervical instability.
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Vértebras Cervicais/cirurgia , Discotomia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Adulto , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologia , Feminino , Humanos , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Radiculopatia/diagnóstico por imagem , Radiculopatia/patologia , Radiculopatia/cirurgia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
OBSERVATION: A 30-year-old patient presented with a left painful pre-auricular tumefaction for one year. CT-scan suggested the diagnosis of temporomandibular synovial cyst or first branchial cleft cyst. This was confirmed by surgery. DISCUSSION: Temporomandibular synovial cysts are rare, the etiology is not documented. Revealing symptoms are those mentioned above. The common treatment is surgery.
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Cisto Sinovial/diagnóstico , Transtornos da Articulação Temporomandibular/diagnóstico , Adulto , Branquioma/diagnóstico , Diagnóstico Diferencial , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , HumanosRESUMO
The aim of the study was to determine the prevalence of overweight and obesity in children in the United Arab Emirates (UAE). Secondary analysis was undertaken of data on 4381 children aged 5-17 years from the 1999 UAE-National Iodine Deficiency Surveillance Study. Data on weight and height from that study were used to calculate body mass index. The prevalence of overweight and obesity was estimated using International Obesity Task Force criteria. Overall, 944 (21.5%) of children were overweight and 601 (13.7%) of these were obese. More girls than boys were overweight (22.9% vs. 20.2%; P < or = 0.001). Non-citizen girls were more likely to be obese (odds ratios [OR] 1.767, 95% confidence intervals [CI] 1.48-2.102) than UAE girls. Boys in the rural areas had the lowest prevalence (23.6%) and were the least likely of all the children to be either overweight (OR 0.785, 95% CI 0.629-0.974) or obese 0.732 (95% CI 0.591-0.912). This study demonstrates a high prevalence of overweight in children in the UAE. Prompt actions are needed to initiate preventative and interventionist strategies to reverse the trend of this emerging epidemic.
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Índice de Massa Corporal , Transtornos da Nutrição Infantil/epidemiologia , Inquéritos Epidemiológicos , Obesidade/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Obesidade/prevenção & controle , Sobrepeso , Prevalência , População Rural/estatística & dados numéricos , Fatores Sexuais , Emirados Árabes Unidos/epidemiologia , População Urbana/estatística & dados numéricosRESUMO
Mainstream preventive interventions often fail to reach poor populations with a high risk of cardiovascular diseases (CVDs) in Pakistan. A community-based CVD primary prevention project aimed at developing approaches to reduce risk factors in such populations was established by Heartfile in collaboration with the National Rural Support Program in the district of Lodhran. The project implemented a range of activities integrated with existing social and health service mechanisms during a three year intervention period 2000/01-03/04. These were targeted in 4 key settings: community health education, mass media interventions, training of health professionals and health education through Lady Health Workers. The project received support from the Department for International Development, U.K. At the community level, a pre-test-post-test quasi-experimental design was used for examining project outcomes related to the community component of the intervention. Pre and post-intervention (training) evaluations were conducted involving all health care providers in randomly selected workshops in order to determine baseline levels of knowledge and the impact of training on knowledge level. In order to assess practices of physician and non-physician health care providers patient interviews, with control comparisons were conducted at each health care facility. Significant positive changes were observed in knowledge levels at a community level in the district of intervention compared with baseline knowledge levels particularly in relation to a heart healthy diet, beneficial level of physical activity, the causes of high blood pressure and heart attack and the effects of high blood pressure and active and passive smoking on health. Significant changes in behaviors at a practice level were not shown in the district of intervention. However the project played a critical role in spurring national action for the prevention and control of non-communicable diseases and introducing sustainable public health interventions for poor communities in Pakistan. (AU)