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Humanitarian engineers responded to the pandemic ventilator shortage of March, 2020 by beginning over 100 open source ventilator projects [Robert L. Read et al. COVID-19 Vent List. Oct. 2020. url: https://docs.google.com/spreadsheets/d/1inYw5H4RiL0AC_J9vPWzJxXCdlkMLPBRdPgEVKF8DZw/edit#gid=0 , Joshua M. Pearce. A review of open source ventilators for COVID-19 and future pandemics. In: F1000Research 9 (2020).]. By ventilator, we mean both an invasive ventilator (requiring intubation of the patient) and non-invasive ventilator (generally supporting spontaneously breathing). Inexpensive ventilator test equipment can facilitate projects forced to be geographically distributed by lockdowns. The VentMon is a modular, open source, IoT-enabled tester that plugs into a standard 22 mm airway between a ventilator and a physical test lung to test any ventilator. The VentMon measures flow, pressure, fractional oxygen, humidity, and temperature. Data is stored and graphed at a data lake accessible to all devlopment team members, and, eventually, clinicians. The open source design of the VentMon, its firmware, and cloud-based software may allow it to be used as a component of modular ventilators to provide a clinical readout. The software system surrounding VentMon has been designed to be as modular and composable as possible. By combining new, openly published standards for data with composable and modifiable hardware, the VentMon forms the beginning of an open system or eco-system of ventilation devices and data. Thanks to grants, 20 VentMons have been given away free of charge to pandemic response teams building open source ventilators.

This paper investigates the optimization of second-order control signals required to produce stable non-linear, deep-water waves using a wedge-shaped, plunger-type wave generator. Both numerical and experimental methods are utilized. A fully non-linear and dispersive potential flow (FNPF) solver developed at DTU is used for the numerical work, following improvements that reduce reflection to 1%. The numerical solver is validated against theoretical and experimental data. A defect correction optimization scheme is employed, resulting in optimized control signals for non-dimensional wave numbers of 2.04-8.17 and steepness of 3-7%. These control signals produce waves that are within 2% of stream function theory solutions for the fundamental harmonic component, and within 10% for the second-order harmonic component. The results demonstrate both the applicability of this optimization procedure and the suitability of a heaving wedge for generating stable non-linear deep-water waves.

Background Palpable breast tumors have traditionally been diagnosed with open biopsy or core biopsy. We propose fine needle aspiration biopsy (FNA) as a reliable, cost-saving initial procedure in these patients. Methods Eighty-five palpable solid breast masses of the breast in 85 patients were classified by a combination of physical examination, mammography, and/or ultrasound as probably benign, indeterminate, or highly suspicious for cancer. All tumors had FNA biopsies. All patients had either a confirmatory open biopsy (55) or close clinical follow-up (30) with a mean followup of 29 months (range 6 to 36). Results Thirty-four patients classified as clinically benign had a benign FNA biopsy. No cancers were detected in this group by either open surgical biopsy or clinical follow-up. Twenty patients were classified clinically as indeterminate. All had FNA biopsies, and 6 were either positive for cancer or suspicious for cancer. Fourteen patients had negative FNA biopsies. Five of the 6 abnormal biopsies had cancer on open biopsies. The 1 false-positive result occurred in a lactating patient. Thirty-one patients were classified clinically as highly suspicious for cancer. Twenty-three were confirmed as cancer with FNA biopsy. Eight needed open surgical biopsy to confirm cancer. All 31 patients clinically suspicious for cancer had cancer. In patients classified clinically as highly suspicious or probably benign, FNA was a reliable first diagnostic step (100% positive predictive value, 100% specificity, 87% sensitivity, and 89% negative predictive value). Conclusions Fine needle aspiration biopsy of solid palpable breast lesions should be the diagnostic procedure of choice for those patients classified clinically as probably benign or clinically as highly suspicious for cancer. Cost analysis revealed elimination of an open biopsy in such cases would save $1,100 per patient. For highly suspicious cases, a negative fine needle aspiration should not deter an open surgical biopsy. For patients classified as indeterminate, fine needle aspiration biopsy results are not reliable enough to determine treatment.

Western Europe has a large number of sovereign micro-states and, in addition, there are also a number of regions of the European Union (EU) which have an unusually high degree of autonomy. This paper examines the economic performance of these micro-states and autonomous regions which is found to be superior to that of adjacent EU regions. The strong economic performance of these micro-states and autonomous regions is shown to be closely related to activity in the financial services sector, tourism and, where present, natural resources. Complex differences among the group of micro-states and autonomous regions are also revealed.

This case report presents a rare anomaly of right upper lobe bronchial anatomy. During routine right upper lobe resection for carcinoma, a common right upper and middle lobe bronchus was found. The resection was completed as a right upper and middle bilobectomy. Knowledge of this uncommon variant was beneficial in performing the pulmonary resection. A review of the literature is presented.