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The low cost and precise tolerances of plastic injection moulded products are a major reason for the popularity of the manufacturing method. The tolerances are greatly influenced by the equipment, raw material and moulding process. One challenge is the raw material variation. This paper presents a production process using cycle based feedback of cycle mass, for control of part properties in the presence of material variation from dual sourcing. The part properties considered are part mass and outer dimensions. The process uses direct cycle mass feedback without additional process measurements in the proposed controller structure. The designed controller structure is tested in a multi-cavity mould while using raw materials from multiple vendors, encompassing five different grades. The results show a total decrease in part mass variance of approximately 50% and a decrease of length and width variance of approximately 40% compared to a moulding process with fixed settings.
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OBJECTIVE: In the present work we investigate how individual differences in at least occasionally using distinct social media platforms is linked to social networks use disorder (SNUD) tendencies. A final sample of n = 2200 participants filled in the AICA-C-9 measure to get insights into individual differences in overuse of social media and participants also indicated which platforms they used at least once a month. RESULTS: The analysis revealed a robust positive association between number of at least occasionally used social media apps and SNUD tendencies (r = .44, p < .001). Further, platforms differed in terms of their "addictive potential", if one takes associations between frequency of distinct platforms use and SNUD tendencies as a proxy for this (and of course the actual descriptive statistics of the SNUD scale for the (non-)frequent user groups of the different platforms). In this regard, at least occasionally using some platforms (here Tumblr, Twitter and TikTok) was associated with highest SNUD tendencies. Moreover, largest differences in terms of effect sizes between the occasional and non-occasional user groups regarding SNUD scores could be observed for Instagram, WhatsApp, and TikTok. The present work bases on data from a larger project investigating associations between SNUD and tobacco use disorder.
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Mídias Sociais , Humanos , Mídias Sociais/estatística & dados numéricos , Feminino , Masculino , Adulto , Alemanha , Rede Social , Adulto Jovem , Pessoa de Meia-Idade , Adolescente , Comportamento Aditivo/psicologia , Comportamento Aditivo/epidemiologiaRESUMO
A 1D model describing the dynamics of an injection moulding machine and the injection process is presented. The model describes an injection cylinder actuated by a dual-pump electro-hydraulic speed-variable drive and the filling, holding and cooling phases of the injection moulding process utilising amorphous polymers. The model is suggested as the foundation for the design of model-based pressure controllers of, e.g., the nozzle pressure. The focus is on using material, mould and machine properties to construct the model, making it possible to analyse and design the dynamic system prior to manufacturing hardware or conducting experiments. Both the presented model and the developed controller show good agreement with experimental results. The proposed method is general in nature and enables the design, analysis and evaluation of the machine, material and mould dynamics for controller design based solely on the physical properties of the system.
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Implicit cognitions may be involved in the development and maintenance of specific Internet use disorders such as problematic social network use (PSNU). In more detail, implicit attitude, attentional biases, approach and avoidance tendencies as well as semantic memory associations are considered relevant in the context of PSNU. This viewpoint article summarizes the available literature on implicit cognitions in PSNU. We systematically reviewed articles of implicit cognitions in PSNU from PubMed, Scopus, Web of Science, and ProQuest databases based on a targeted search strategy and assessed using predefined inclusion and exclusion criteria. The present findings suggest that specific implicit cognitions are important in the context of PSNU and therefore show parallels to other addictive behaviors. However, the empirical evidence is limited to a few studies on this topic. Implicit cognitions in PSNU should be explored in more depth and in the context of other affective and cognitive mechanisms in future work.
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Viés de Atenção , Comportamento Aditivo , Humanos , Cognição , Comportamento Aditivo/psicologia , Rede SocialRESUMO
BACKGROUND: To investigate the effects of a reversed segment of the distal small intestine to improve weight gain in an experimental short bowel syndrome (SBS) model in piglets. METHODS: Twenty-four piglets underwent resection of 70% of the distal small intestine. In half of the animals a conventional anastomosis was performed, and in the other half, the distal 25 cm of the remnant jejunum was reversed before the intestinal continuity was recreated. Weight was measured daily until day 28, where the animals were euthanized. Glucagon-Like Peptide-2 (GLP-2) and Glucose-dependent Insulinotropic Peptide (GIP) was measured pre- and postoperatively at day 28. RESULTS: The group with reversal of small intestine had a significant lower weight gain at 5.26 ± 3.39 kg (mean ± SD) compared to the control group with 11.14 ± 3.83 kg (p < 0.05). In the control group greater villus height and crypt depth was found distally, and greater muscular thickness was found proximally in the intervention group. GLP-2 and GIP levels increased significantly in the control group. CONCLUSIONS: Treatment of short bowel syndrome with a reversed jejunal segment of 25 cm had a detrimental effect on the weight gain.
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Síndrome do Intestino Curto , Adaptação Fisiológica , Animais , Modelos Animais de Doenças , Peptídeo 2 Semelhante ao Glucagon , Intestino Delgado/cirurgia , Síndrome do Intestino Curto/cirurgia , Suínos , Aumento de PesoRESUMO
OBJECTIVE: Psychotherapy training is mandatory for physicians to qualify as psychiatrists in Denmark. Evidence for the effectiveness of psychotherapy has increased, and psychotherapy is increasingly included in international treatment guidelines. The authors investigated how psychiatrists in training in Denmark evaluate the opportunities to practice psychotherapy in their training and the quality of the supervision they receive in psychotherapy training, particularly for cognitive behavioral therapy (CBT). METHOD: The authors conducted a survey regarding psychotherapy training and CBT supervision among psychiatrists in training at Danish psychiatric specialist training courses. They investigated respondents' interest and experience in psychotherapy and respondents' views on the relevance and feasibility of performing psychotherapy and receiving supervision in their psychiatry training. RESULTS: Eighty-eight percent of the psychiatrists in training found psychotherapy to be a relevant part of their training; however, 77 % found it difficult to find time to practice psychotherapy and 44 % felt that practicing psychotherapy was a strain on their employer. Thirty-six percent and 53 %, respectively, had difficulties securing psychodynamic and CBT supervision. In CBT supervision, more than 60 % reported supervision that appeared to be below the expected CBT supervision standard and often so much below it might not qualify as CBT supervision. CONCLUSIONS: There is a need to focus on how to better integrate psychotherapy and supervision in the Danish psychiatric training program. Good CBT supervision may be lacking, and a way to ensure high-quality supervision is required.
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Terapia Cognitivo-Comportamental/educação , Internato e Residência , Mentores , Psiquiatria/educação , Currículo/normas , Dinamarca , HumanosRESUMO
Fuels from renewable resources have gained worldwide interest due to limited fossil oil sources and the possible reduction of atmospheric greenhouse gas. One of these fuels is so called biodiesel produced from vegetable oil by transesterification into fatty acid methyl esters (FAME). To get a first insight into changes of health hazards from diesel engine emissions (DEE) by use of biodiesel scientific studies were reviewed which compared the combustion of FAME with common diesel fuel (DF) for legally regulated and non-regulated emissions as well as for toxic effects. A total number of 62 publications on chemical analyses of DEE and 18 toxicological in vitro studies were identified meeting the criteria. In addition, a very small number of human studies and animal experiments were available. In most studies, combustion of biodiesel reduces legally regulated emissions of carbon monoxide, hydrocarbons, and particulate matter. Nitrogen oxides are regularly increased. Among the non-regulated emissions aldehydes are increased, while polycyclic aromatic hydrocarbons are lowered. Most biological in vitro assays show a stronger cytotoxicity of biodiesel exhaust and the animal experiments reveal stronger irritant effects. Both findings are possibly caused by the higher content of nitrogen oxides and aldehydes in biodiesel exhaust. The lower content of PAH is reflected by a weaker mutagenicity compared to DF exhaust. However, recent studies show a very low mutagenicity of DF exhaust as well, probably caused by elimination of sulfur in present DF qualities and the use of new technology diesel engines. Combustion of vegetable oil (VO) in common diesel engines causes a strongly enhanced mutagenicity of the exhaust despite nearly unchanged regulated emissions. The newly developed fuel "hydrotreated vegetable oil" (HVO) seems to be promising. HVO has physical and chemical advantages compared to FAME. Preliminary results show lower regulated and non-regulated emissions and a decreased mutagenicity.
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Biocombustíveis/toxicidade , Gasolina/toxicidade , Petróleo/toxicidade , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/análise , Animais , Biocombustíveis/análise , Dano ao DNA/efeitos dos fármacos , Gasolina/análise , Humanos , Hidrocarbonetos/análise , Modelos Animais , Mutagênicos , Óxidos de Nitrogênio/análise , Material Particulado/análise , Material Particulado/toxicidade , Petróleo/análise , Óleos de Plantas/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Emissões de Veículos/análiseRESUMO
BACKGROUND: This follow-up study compared patients with schizophrenia with co-occurring substance use disorder to patients with schizophrenia and no substance use disorder. AIMS: To investigate the prognostic significance of the effects of substance use disorders on the course of schizophrenia. METHOD: Patients with schizophrenia and co-occurring substance use disorder (n=107), and patients with schizophrenia only (n=119) were followed over a 15-year period through the use of national hospitalization registers, data for time and cause of death, and data for homelessness or institutionalization. RESULTS: The median length of psychiatric hospitalization was 12 days for a patient with dual diagnosis, and 21 days for patients with schizophrenia only. Patients with dual diagnosis displayed a significantly elevated usage of all types of hospital contacts except inpatient treatment for non-psychiatric disorders. In three types of hospital contacts, patients with co-occurring substance use had approximately two to three times as many hospitalizations as did patients with schizophrenia only. Rates for homelessness and institutionalization were similar in both groups. Patients with a dual diagnosis were also significantly more at risk of dying during follow-up than were patients with schizophrenia only. CONCLUSIONS: The findings suggest that the long-term course of schizophrenia is considerably more severe in patients who have a dual diagnosis compared to patients with schizophrenia only Substance use disorders have a substantial impact on the hospitalization rates of patients with schizophrenia, as well as on life expectancy. Patients with co-morbid substance abuse are more likely to be admitted for treatment during a given year although they have briefer contact with treatment.
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Esquizofrenia/diagnóstico , Esquizofrenia/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Estudos Transversais , Dinamarca/epidemiologia , Diagnóstico Duplo (Psiquiatria)/métodos , Feminino , Pessoas Mal Alojadas/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Unidade Hospitalar de Psiquiatria/estatística & dados numéricos , Fatores de Risco , Esquizofrenia/mortalidade , Transtornos Relacionados ao Uso de Substâncias/mortalidade , Fatores de Tempo , Adulto JovemRESUMO
OBJECTIVES: To assess Danish surgical departments' attitudes to and clinical guidelines on the use of perioperative thrombo-prophylaxis (TP). MATERIALS AND METHODS: Questionnaires regarding TP were sent to Danish departments which performed major surgery in 2005. The questionnaires contained questions regarding the use of TP routinely after clinical guidelines for both elective and acute surgery, indications for the use of TP, the type of TP and the duration of the TP treatment. The results are registered descriptively. The results are compared with five previously performed surveys from 1981-2000. RESULTS: In the five surveys from 1981 to 2000, 85%, 90%, 92%, 95%, 93% answered the questionnaire, in the present survey 88% answered. Since the beginning of these surveys, there has been a significant increase in the use of TP following clinical guidelines from approximately 50% in 1981 to 96% of the departments performing major surgery in 2005. In acute surgery we found a significant increase in the number of departments using TP following clinical guidelines from 43% in 2000 to 81% in 2005 (p<0.01 Fishers exact test). All departments that used TP employed low molecular weight heparin. The use of prolonged TP was sporadic. CONCLUSION: 30 years after the first evidence in favour of TP was published, 96% of surgical departments which perform major surgery use TP routinely based on international clinical recommendations. A large number of departments use TP in connection with acute surgery in comparison with previous surveys. A future task is more focus on the use of prolonged TP after major surgical procedures.
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Complicações Intraoperatórias/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Trombose/prevenção & controle , Anticoagulantes/uso terapêutico , Atitude do Pessoal de Saúde , Dinamarca , Fibrinolíticos/uso terapêutico , Fidelidade a Diretrizes , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Padrões de Prática Médica , Pré-Medicação , Fatores de Risco , Centro Cirúrgico Hospitalar , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Inquéritos e Questionários , Trombose/etiologiaRESUMO
BACKGROUND: Citations in scientific articles may tend to favor the views presented. We studied whether there is such reference bias in narrative review articles that discuss interventions against house dust mites for people with asthma. DESIGN: Systematic review of reviews identified in a Medline search that expressed an opinion about the clinical effects of physical or chemical intervention methods. MAIN OUTCOME MEASURE: Positive bias was judged to have occurred if the reference list contained a higher proportion of trial references with significant results than among all trials available to the authors (published 2 years or more prior to the review). RESULTS: Seventy reviews were included, of which 63 (90%) recommended physical interventions. Forty-six reviews had trial references, 4 of these only to chemical interventions. In the remaining 42 reviews, reference bias was detected (P=2 x 10-8). The most quoted trial had only 7 patients per group, its claimed significant result was probably erroneous, and it did not report a clinical outcome. Intervention recommendations were often based on nonrandomized evidence, and the most quoted nonrandomized controlled study had included only 10 patients per group but claimed very positive results. CONCLUSION: The narrative review articles were severely biased, and their positive intervention recommendations are at variance with the systematic Cochrane Review on this topic and a recent very large trial of physical intervention, both of which failed to find an effect.