Hangprinter for large scale additive manufacturing using fused particle fabrication with recycled plastic and continuous feeding

The life cycle of plastic is a key source of carbon emissions. Yet, global plastics production has quadrupled in 40 years and only 9 % has been recycled. If these trends continue, carbon emissions from plastic wastes would reach 15 % of global carbon budgets by 2050. An approach to reducing plastic waste is to use distributed recycling for additive manufacturing (DRAM) where virgin plastic products are replaced by locally manufactured recycled plastic products that have no transportation-related carbon emissions. Unfortunately, the design of most 3-D printers forces an increase in the machine cost to expand for recycling plastic at scale. Recently, a fused granular fabrication (FGF)/fused particle fabrication (FPF) large-scale printer was demonstrated with a GigabotX extruder based on the open source cable driven Hangprinter concept. To further improve that system, here a lower-cost recyclebot direct waste plastic extruder is demonstrated and the full designs, assembly and operation are detailed. The <$1,700 machine's accuracy and printing performance are quantified, and the printed parts mechanical strength is within the range of other systems. Along with support from the Hangprinter and DUET3 communities, open hardware developers have a rich ecosystem to modify in order to print directly from waste plastic for DRAM.

A highly virulent variant of HIV-1 circulating in the Netherlands

We discovered a highly virulent variant of subtype-B HIV-1 in the Netherlands. One hundred nine individuals with this variant had a 0.54 to 0.74 log₁₀ increase (i.e., a ~3.5-fold to 5.5-fold increase) in viral load compared with, and exhibited CD4 cell decline twice as fast as, 6604 individuals with other subtype-B strains. Without treatment, advanced HIV-CD4 cell counts below 350 cells per cubic millimeter, with long-term clinical consequences-is expected to be reached, on average, 9 months after diagnosis for individuals in their thirties with this variant. Age, sex, suspected mode of transmission, and place of birth for the aforementioned 109 individuals were typical for HIV-positive people in the Netherlands, which suggests that the increased virulence is attributable to the viral strain. Genetic sequence analysis suggests that this variant arose in the 1990s from de novo mutation, not recombination, with increased transmissibility and an unfamiliar molecular mechanism of virulence.

Virological and Social Outcomes of HIV-Infected Adolescents and Young Adults in The Netherlands Before and After Transition to Adult Care

BACKGROUND

As a result of effective combination antiretroviral therapy (cART) and advanced supportive healthcare, a growing number of human immunodeficiency virus (HIV)-infected children survive into adulthood. The period of transition to adult care is often associated with impaired adherence to treatment and discontinuity of care. We aimed to evaluate virological and social outcomes of HIV-infected adolescents and young adults (AYAs) before and after transition, and explore which factors are associated with virological failure.

METHODS

We included 59 HIV-infected AYAs from the Netherlands who had entered into pediatric care and transitioned from pediatric to adult healthcare. We used HIV RNA load and cART data from the Dutch Stichting HIV Monitoring database (1996-2014), and collected social and treatment data from patients' medical records from all Dutch pediatric HIV treatment centers and 14 Dutch adult treatment centers involved. We evaluated risk factors for virological failure (VF) in a logistic regression model adjusted for repeated measurements.

RESULTS

HIV VF occurred frequently during the study period (14%-36%). During the transition period (from 18 to 19 years of age) there was a significant increase in VF compared with the reference group of children aged 12-13 years (odds ratio, 4.26 [95% confidence interval, 1.12-16.28]; P = .03). Characteristics significantly associated with VF were low educational attainment and lack of autonomy regarding medication adherence at transition.

CONCLUSIONS

HIV-infected AYAs are vulnerable to VF, especially during the transition period. Identification of HIV-infected adolescents at high risk for VF might help to improve treatment success in this group.

Inflammatory cell distribution in guinea pig airways and its relationship to airway reactivity

Although airway inflammation and airway hyperreactivity are observed after allergen inhalation both in allergic humans and animals, little is known about the mechanisms by which inflammatory cells can contribute to allergen-induced airway hyperreactivity. To understand how inflammatory cell infiltration can contribute to airway hyperreactivity, the location of these cells within the airways may be crucial Using a guinea pig model of acute allergic asthma, we investigated the inflammatory cell infiltration in different airway compartments at 6 and 24 h (i.e. after the early and the late asthmatic reaction, respectively) after allergen or saline challenge in relation to changes in airway reactivity (AR) to histamine. At 6 h after allergen challenge, a threefold (p < 0.01) increase in the AR to histamine was observed. At 24 h after challenge, the AR to histamine was lower, but still significantly enhanced (1.6-fold, p < 0.05). Adventitial eosinophil and neutrophil numbers in both bronchi and bronchioli were significantly increased at 6 h post-allergen provocation as compared with saline (p < 0.01 for all), while there was a strong tendency to enhanced eosinophils in the bronchial submucosa at this time point (p = 0.08). At 24h after allergen challenge, the eosinophilic and neutrophilic cell infiltration was reduced. CD3+ T lymphocytes were increased in the adventitial compartment of the large airways (p < 0.05) and in the parenchyma (p < 0.05) at 24h post-allergen, while numbers of CD8+ cells did not differ from saline treatment at any time point post-provocation. The results indicate that, after allergen provocation, inflammatory cell numbers in the airways are mainly elevated in the adventitial compartment. The adventitial inflammation could be important for the development of allergen-induced airway hyperreactivity.

[Team care: a necessity for a child with HIV infection]

In four children, a boy aged 2.5 years, a girl of 4, her brother of 7 years and a girl aged 10 months, HIV infection was diagnosed. Since 1996 HIV-infected children in the Netherlands are treated with a combination of two nucleoside analogs and a protease-inhibitor. This therapy improves the quality of life, increases the life expectancy of HIV-infected children and is generally well tolerated. However, the current combination therapy is complex and puts a burden on the child and the family. Therefore, long term compliance will be difficult. Moreover, the majority of the families have extremely difficult social circumstances which interfere with an optimal medical treatment for the child. The parents of three of the children were refugees from African countries. Intensive support of the family by a team of health care and social workers is usually necessary to make antiretroviral combination therapy possible. Care directed at the individual needs of the child and family is crucial to help this vulnerable group of children and families in our society.

[Increase of reported HIV-1 infections in children in Netherlands, 1982-1997: more vertical transmission and a greater proportion of other than Dutch children]

OBJECTIVE

To document the trend of the yearly number of newly diagnosed paediatric HIV-1 infections in the Netherlands.

DESIGN

Retrospective registration regarding the period January 1st 1982-December 31st 1994 and prospective registration regarding January 1st 1995-December 31st 1997.

METHOD

Based on reports to the Dutch Paediatric Surveillance Unit (Nederlands Signaleringscentrum Kindergeneeskunde) numbers of paediatric HIV-1 diagnoses (0-18 years) in the Netherlands were determined prospectively. Retrospective figures were determined by asking the paediatricians also to report the HIV-1 infected children diagnosed before the first of January 1995. A comparison was made with data from the Inspectorate for Health Care (Inspectie voor de Gezondheidszorg). All reports were followed up with standard questionnaires.

RESULTS

In both periods an increase in the number of newly diagnosed paediatric HIV-1 infections per year in the Netherlands was seen (1982-1994: 74 children; 1995-1997: 43 children). The majority of the parents of the HIV-1 infected children originated from outside the Netherlands (1982-1994: 57%; 1995-1997: 91%), often from HIV-endemic countries (1982-1994: 41%; 1995-1997: 77%). The main mode of infection was vertical transmission (1982-1994: 62%; 1995-1997: 84%); diagnosis in allochtonous children was made relatively late.

CONCLUSION

The current rise in the absolute number of newly detected paediatric HIV-1 infections in the Netherlands is predominantly due to the growing group of children born to parents who originate from HIV-endemic countries.