Maker communities and the COVID-19 pandemic: a longitudinal analysis of Thingiverse's response to supply shortages.

The COVID-19 pandemic profoundly affected various aspects of daily life, particularly the supply and demand of essential goods, resulting in critical shortages. This included personal protective equipment for medical professionals and the general public. To address these shortages, online 'maker communities' emerged, aiming to develop and locally manufacture critical products. While some organized efforts existed, the majority of initiatives originated from individuals and groups on platforms like Thingiverse. This paper presents a longitudinal analysis of Thingiverse, one of the largest maker community websites, to examine the pandemic's effects. Our findings reveal a surge in community output during the initial lockdown periods in major contributing nations (primarily those in the Western Hemisphere), followed by a subsequent decline. Additionally, throughout 2020, pandemic-related products dominated uploads and interactions during this period. Based on these observations, we propose recommendations to expedite the community's ability to support local, national and international responses to future disasters.

[Mitoxantrone-induced acute left heart failure after intrapleural administration]. / Mitoxantron-induzierte akute Linksherzinsuffizienz nach intrapleuraler Applikation.

A 79-year-old female was admitted to our hospital because of a malignant pleural effusion following mastectomy 4 years ago. In the patient's history arterial hypertension and previous inferior myocardial infarction have been known. Two doses of 20 mg mitoxantrone were installed intrapleurally at an interval of 4 weeks. Six hours after the second mitoxantrone application and the patient had increasing dyspnea with consecutive left heart failure, pulmonary congestion, and a drop of blood pressure. The white-cell count was 14800/mm3. The levels of creatinine phosphokinase (CPK), lactate dehydrogenase (LDH) and serum aspartate aminotransferase (SGOT) were in the normal range. Transthoracic echocardiography showed concentric left ventricular hypertrophy and a markedly decreased fractional shortening, but no left ventricular dilatation. The electrocardiogram showed newly appeared down-sloping ST-segments and inverted T-waves. Clinical recovery was achieved after 6 days by application of oxygen, dobutamine and furosemide followed by angiotensin converting enzyme inhibition and digitalis. In the echocardiographic control examination 14 days later left ventricular function had normalized. The changes of electrocardiogram normalized 4 weeks later.

[Qualitative control over quantitative MR tomography: in vitro and in vivo checks on relaxation time measurements]. / Qualitätskontrolle der quantitativen MR-Tomographie: In-vitro- und In-vivo-Uberprüfung von Relaxationszeitmessungen.

In-vivo and in-vitro checks on measurements of relaxation times in MRI have been carried out as part of quality control. For the in-vitro experiments we used 13 reagents consisting of varying concentrations of copper sulphate manganese sulphate, gadolinium solutions and various oils as well as water. For in-vivo measurements we used liver parenchyma and fat in three subjects. Eight different sequences were performed; intra- and interindividual variations and comparison of three similar MRI units showed average variations of 2-3% for T1 and 3-4% variations for T2 relaxation times. This margin of error makes quantitative MRI acceptable for clinical use.