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Engineering technology plays a pivotal role in the delivery of health care in under-resourced countries by providing an infrastructure to improve patient outcomes. However, sustainability of these technologies is difficult in these settings oftentimes due to limited resources or training. The framework presented in this editorial focuses on establishing medical and laboratory equipment sustainability in developing countries and is comprised of four steps: 1) establishing reliable in-country relationships with stakeholders, 2) identifying needs for sustainable solutions locally, 3) exploring potential solutions and assessing their effort-to-impact ratios, and 4) working with strategic partners to implement solutions with clear performance metrics. By focusing on the sustainability of donated equipment instead of the equipment itself, this method presented distinguishes itself from other philanthropic endeavors in the field by seeking to establish preventive maintenance habits that can impact clinical outcomes of a community long term. Application of this methodology is reported in the Original Research Article \"A Low-Cost Humidity Control System to Protect Microscopes in a Tropical Climate\" by Asp et. al.

A clean and functional microscope is necessary for accurate diagnosis of infectious diseases. In tropical climates, high humidity levels and improper storage conditions allow for the accumulation of debris and fungus on the optical components of diagnostic equipment, such as microscopes. Our objective was to develop and implement a low-cost, sustainable, easy to manage, low-maintenance, passive humidity control chamber to both reduce debris accumulation and microbial growth onto the optical components of microscopes. Constructed from easily-sourced and locally available materials, the cost of each humidity control chamber is approximately $2.35 USD. Relative humidity levels were recorded every 30 minutes over a period of 10 weeks from two chambers deployed at the Belize Vector and Ecology Center and the University of Belize. The humidity control chamber deployed at the University of Belize maintained internal relative humidity at an average of 35.3% (SD = 4.2%) over 10 weeks, while the average external relative humidity was 86.4% (SD = 12.4%). The humidity control chamber deployed at the Belize Vector and Ecology Center effectively maintained internal relative humidity to an average of 54.5% (SD = 9.4%) over 10 weeks, while the average external relative humidity was 86.9% (SD = 12.9%). Control of relative humidity is paramount for the sustainability of medical equipment in tropical climates. The humidity control chambers reduced relative humidity to levels that were not conducive for fungal growth while reducing microscope contamination from external sources. This will likely extend the service life of the microscopes while taking advantage of low-cost, locally sourced components.

An increased bone mineral density (BMD) in the proximity to tendon insertion can improve rotator cuff repair and healing. However, how a decrease of BMD in the humeral head affects the biomechanical properties of the rotator cuff tendon is still unclear. Previous studies have demonstrated ovariectomy in animals to lead to osteoporosis and decreased BMD, and Teriparatide (PTH) administration to improve BMD and strength of bone. This study aimed to explore the correlation between humeral head BMD and infraspinatus (ISP) tendon insertion strength, and if an increase in bone quantity of the humeral head can improve the strength of the rotator cuff. Eighteen New England white rabbits were divided into the 3 groups: Control, Ovariectomy-Saline (OVX-Saline), and Ovariectomy-PTH (OVX-PTH). The OVX-Saline group and the OVX-PTH were administered daily saline and Teriparatide injections for 8 weeks starting at 17 weeks of OVX. BMD of the humeral head was measured, the ISP tendon failure load was tested and the failure stress was calculated. One specimen from each group was used for histological analysis. Linear regression analysis was used to derive equations for the BMD and failure stress. Significant differences were observed in the measured humeral head BMD of the Control and OVX-PTH groups compared to the OVX-Saline group (P = 0.0004 and P = 0.0024, respectively). No significant difference was found in failure stress among the three groups, but an expected trend with the control group and OVX-PTH group presenting higher failure strength compared to the OVX-Saline group. BMD at the humeral head showed a positive linear correlation with stress (r2 = 0.54). Histology results showed the superiority in OVX-PTH group ISP enthesis compared to the OVX-Saline group. Bone loss of the humeral head leads to decreased tendon/bone insertion strength of the infraspinatus tendon enthesis. Teriparatide administration can increase bone density of the humeral head and may improve the mechanical properties of the infraspinatus tendon enthesis.

The MRTX portable lightweight respirator (MRTX) provides noninvasive respiratory support using biphasic extrathoracic ventilation via a cuirass fitted around the patient's chest. MRTX was applied with or without full protective gear, on adult volunteers simulating nerve agent (NA) victims by nonmedical caregivers. Assessment was made based on scores for correct positioning of the cuirass, quality of seal, and rapid ness. For the unprotected and protected personnel, the respective median (±95% confidence interval) scores for correct positioning of the cuirass were 2 (1.4-1.9) and 1 (1.2-1.8) (n = 15 per group, P = NS); quality of seal scores were 2 (1.5-2.0) and 2 (1.3-1.8) ( P = NS); and mean (±SD) time required for instituting mechanical ventilation was 90.5 ± 10.9 and 100.3 ± 7.9 seconds ( P < .05). The respirator was activated at first attempt 11 times in the group of 15 without protective gear and 8 times in the group of 15 with protective gear ( P = NS). Biphasic cuirass ventilation is an easily learned and rapidly applied method suitable for use by nonmedical personnel, even when wearing cumbersome protective gear.

Objectives: To evaluate the speed by which cuirass application, followed by biphasic extra-thoracic ventilation, can be instituted by full anti-chemical protective gear-wearing physicians. Materials and Methods: Ten physicians of variable subspecialties applied a cuirass on an adult volunteer and instituted biphasic extra-thoracic ventilation, using the RTX respirator (Medivent, London, UK). Endotracheal (ET) intubation and manual ventilation of a mannequin and its ventilation was comparatively assessed. Performances were conducted in a prospective, crossover, randomized manner. Times to successful applications as well as failure rates were recorded. Results: Cuirass application was performed more rapidly (102 ± 9 s, 177 ± 31 s, respectively, P < .01) and with a slightly lower failure rate than ET intubation. Conclusions: Physicians wearing full anti-chemical protective gear applied the cuirass and instituted biphasic extra-thoracic ventilation faster than ET intubation and manual positive pressure ventilation. Extra-thoracic ventilation should be further evaluated as an option for emergent respiratory support during toxic mass casualty events.

Introduction An increased bone mineral density (BMD) in the proximity to tendon insertion can improve rotator cuff repair and healing. However, how a decrease of BMD in the humeral head affects the biomechanical properties of the rotator cuff tendon is still unclear. Previous studies have demonstrated ovariectomy in animals to lead to osteoporosis and decreased BMD, and Teriparatide (PTH) administration to improve BMD and strength of bone. This study aimed to explore the correlation between humeral head BMD and infraspinatus (ISP) tendon insertion strength, and if an increase in bone quantity of the humeral head can improve the strength of the rotator cuff. Materials and Methods Eighteen New England white rabbits were divided into the 3 groups: Control, Ovariectomy-Saline (OVX-Saline), and Ovariectomy-PTH (OVX-PTH). The OVX-Saline group and the OVX-PTH were administered daily saline and Teriparatide injections for 8 weeks starting at 17 weeks of OVX. BMD of the humeral head was measured, the ISP tendon failure load was tested and the failure stress was calculated. One specimen from each group was used for histological analysis. Linear regression analysis was used to derive equations for the BMD and failure stress. Results Significant differences were observed in the measured humeral head BMD of the Control and OVX-PTH groups compared to the OVX-Saline group (P = 0.0004 and P = 0.0024, respectively). No significant difference was found in failure stress among the three groups, but an expected trend with the control group and OVX-PTH group presenting higher failure strength compared to the OVX-Saline group. BMD at the humeral head showed a positive linear correlation with stress (r2 = 0.54). Histology results showed the superiority in OVX-PTH group ISP enthesis compared to the OVX-Saline group. Conclusion Bone loss of the humeral head leads to decreased tendon/bone insertion strength of the infraspinatus tendon enthesis. Teriparatide administration can increase bone density of the humeral head and may improve the mechanical properties of the infraspinatus tendon enthesis.

This dissertation investigates a novel method to non-invasively assess the mechanical response of the spine to shear vibration using magnetic resonance elastography (MRE). There are many imaging techniques to characterize disc degeneration; however, limited work has been done to assess the material properties of the intervertebral disc (IVD) within the intact spine. Also, existing imaging methods are limited in the detection of early stage changes with disc degeneration. MRE is a MRI-based technique for non-invasively mapping the mechanical properties of tissues in vivo. The general hypothesis we are testing in this work is that mechanical changes in the intervertebral disc with early disc degeneration are detectable due to abnormal shear vibration propagation across the disc space using MRE and may precede changes visible using standard anatomical imaging methods. In this work, MRE was demonstrated in isolated lumbar spinal motion segments at a range of high mechanical frequencies (1-1.5 kHz) using a standard clinical 1.5T MR scanner. Propagating waves were visualized in an axial cross-section of the IVD, which resembled wave patterns predicted using finite element modeling and were used to estimate the shear stiffness of the nucleus pulposus region of the IVD. In addition, an MRE technique was developed to visualize low frequency shear vibration (80 Hz) throughout the thoracolumbar spine in vitro. Mechanical changes induced in an animal model of early-stage disc degeneration were quantified using MRE and mechanical testing of disc laxity. MRE was able to detect altered mechanical properties from discogenic instability in the spine segments, which was verified with mechanical testing results. Further, this work demonstrates the feasibility of in vivo spine MRE in a healthy volunteer to visualize shear wave propagation throughout the thoracolumbar spine. MRE may be valuable for the diagnosis of spinal instability and early disc degeneration, as well as monitoring changes in disc health.

The herbicide Sandoz 6706 (4-chloro-5-(dimethylamino)-2-α,α,α, (trifluoro-m-tolyl)-3(2H)-pyridazinone), when applied as a preplant soil treatment at a concentration of 0.05 μg/g reduced the content of β-carotene and chlorophylls in 21-day-old wheat seedlings (Triticum aestivum L.) by 55% and 29%, respectively, without affecting the fresh or dry matter of the seedlings. At 0.8 μg/g, the herbicide reduced the content of β-carotene and chlorophyll by as much as 98%, while the fresh weight of the albino seedlings was reduced by only 24%. The effect of the herbicide on chlorophyll b was much stronger than on chlorophyll a. Time course studies of pigment synthesis in Sandoz 6706-treated seedlings showed that chlorophyll, β-carotene, cyclic xanthophylls, phytoene, phytofluene, and ζ-carotene were accumulating during the first 7 days after sowing. Later on, there was a sharp decline in the content of chlorophyll and β-carotene and a gradual reduction in the content of phytofluene, ζ-carotene, and cyclic xanthophylls; the content of phytoene remained essentially unchanged. Coinciding with the drop in content of β-carotene and chlorophyll, there was a remarkable increase in the content of epoxy phytoene. It is suggested that Sandoz 6706 might act as an inhibitor of the cyclization reaction in the biosynthetic pathway of carotenoids and that other effects, such as the bleaching of chlorophyll, are a consequence of this inhibition.

The herbicide Sandoz 6706 (4-chloro-5-(dimethylamino)-2-α,α,α, (trifluoro-m-tolyl)-3(2H)-pyridazinone), when applied as a preplant soil treatment at a concentration of 0.05 μg/g reduced the content of β-carotene and chlorophylls in 21-day-old wheat seedlings (Triticum aestivum L.) by 55% and 29%, respectively, without affecting the fresh or dry matter of the seedlings. At 0.8 μg/g, the herbicide reduced the content of β-carotene and chlorophyll by as much as 98%, while the fresh weight of the albino seedlings was reduced by only 24%. The effect of the herbicide on chlorophyll b was much stronger than on chlorophyll a. Time course studies of pigment synthesis in Sandoz 6706-treated seedlings showed that chlorophyll, β-carotene, cyclic xanthophylls, phytoene, phytofluene, and ζ-carotene were accumulating during the first 7 days after sowing. Later on, there was a sharp decline in the content of chlorophyll and β-carotene and a gradual reduction in the content of phytofluene, ζ-carotene, and cyclic xanthophylls; the content of phytoene remained essentially unchanged. Coinciding with the drop in content of β-carotene and chlorophyll, there was a remarkable increase in the content of epoxy phytoene. It is suggested that Sandoz 6706 might act as an inhibitor of the cyclization reaction in the biosynthetic pathway of carotenoids and that other effects, such as the bleaching of chlorophyll, are a consequence of this inhibition.