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The jackfruit is the largest fruit on the Earth, reaching upwards of 35 kg and falling from heights of 25 m. To survive such high energy impacts, it has evolved a unique layered configuration with a thorny exterior and porous tubular underlayer. During compression, these layers exhibit a progressive collapse mechanism where the tubules are first to deform, followed by the thorny exterior, and finally the mesocarp layer in between. The thorns are composed of lignified bundles which run longitudinally from the base of the thorn to the tip and are embedded in softer parenchymal cells, forming a fiber reinforced composite. The mesocarp contains more lignin than any of the other layers while the core appears to contain more pectin giving rise to variations in compressive and viscoelastic properties between the layers. The surface thorns provide a compelling impact-resistant feature for bioinspiration, with a cellular structure that can withstand large deformation without failing and wavy surface features which densify during compression without fracturing. Even the conical shape of the thorns is valuable, presenting a gradually increasing surface area during axial collapse. A simplified model of this mechanism is put forward to describe the force response of these features. The thorns also distribute damage laterally during impact and deflect cracks along their interstitial valleys. These phenomena were observed in 3D printed, jackfruit-inspired designs which performed markedly better than control prints with the same mass. STATEMENT OF SIGNIFICANCE: Many biological materials have evolved remarkable structures that enhance their mechanical performance and serve as sources of inspiration for engineers. Plants are often overlooked in this regard yet certain botanical components, like nuts and fruit, have shown incredible potential as blueprints for improved impact resistant designs. The jackfruit is the largest fruit on Earth and generates significant falling impact energies. Here, we explore the jackfruit's structure and its mechanical capabilities for the first time. The progressive failure imparted by its multilayered design and the unique collapse mode of the surface thorns are identified as key mechanisms for improving the fruit's impact resistance. 3D printing is used to show that these structure-property benefits can be successfully transferred to engineering materials., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Purpose: Phosphorus (P) lost from agricultural land by erosion, runoff, throughflow and leaching is of major concern for water resource managers worldwide. Previous study on soils from cropping land of southwest Western Australia suggested P loss as dissolved unreactive P (DURP) via leaching, but the implications for processes and rates of P transport in soils are not known., Material and Methods: Two contrasting soil profiles (sand and loam) from cropping land of southwest Western Australia were exposed to artificial rain in packed boxes and field runoff plots to examine P forms and fluxes in runoff, throughflow, leachate and soil solution after three P rates of application (equivalent to 0, 20 and 40kg P/ha). Solutions were analyzed for total P (TP), dissolved reactive P (DRP) and total dissolved P (TDP). Particulate P (PP) and DURP were calculated by subtracting DRP from TP and TDP respectively., Result and Discussion: In the sand profile, about 90% or more of P losses via runoff and leachate were in DURP and PP forms, whereas DRP was a minor contributor. Phosphorus load in soil solution, throughflow, leachate and run-off increased with increasing P rate. The relatively higher affinity of soil for DRP compared to DURP might cause the latter to be more mobile through profile in association with colloidal compounds <0.2μm. Higher PP concentration for loam soil via throughflow is exacerbated by dispersed clay, which could be an additional process influencing P mobility in loam and duplex soils., Conclusion: The DRP played a limited role in P transport compared to PP and DURP that both appeared to be associated with soil particles or soil colloids in runoff, throughflow, leachate and soil solution. Further characterization of the latter forms of P is needed so that management practices can be developed to minimize P losses., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The purple bacteria Rhodobacter sphaeroides serve as a promising biocatalyst in the photo-microbial fuel cell system (photo-MFC). This gram-negative species performs highly efficient anoxygenic photosynthesis that ensures an anaerobic environment in the anode compartment. Previous studies incorporating R. sphaeroides into photo-MFC were conducted using platinum as the anode electrode. In this study, we detected a steady current generation of R. sphaeroides in a bioelectrochemical system where glassy carbon was the working electrode and a typical growth medium was the electrolyte. The bioelectricity generation synchronized with the supplementation of reduced carbon source and showed immediate response to illumination, which strongly indicated the correlation between the observed current and the cytoplasmic quinone activity. Modifications of the endogenous electron flows mediated by quinone pool are shown to have significantly enhanced the bioelectricity generation. We anticipate that the findings in this study would advance future optimization of R. sphaeroides as an anode strain, as well as facilitate the study of bioenergetics in photosynthetic bacteria., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Monocytes and T helper (T(H)) cells rapidly infiltrate inflamed tissues where monocytes differentiate into inflammatory dendritic cells (DCs) through undefined mechanisms. Our studies indicate that T(H) cells frequently interact with monocytes in inflamed skin and elicit the differentiation of specialized DC subsets characteristic of these lesions. In psoriasis lesions, T(H)1 and T(H)17 cells interact with monocytes and instruct these cells to differentiate into T(H)1- and T(H)17-promoting DCs, respectively. Correspondingly, in acute atopic dermatitis, T(H)2 cells interact with monocytes and elicit the formation of T(H)2-promoting DCs. DC formation requires GM-CSF and cell contact, whereas T(H) subset specific cytokines dictate DC function and the expression of DC subset specific surface molecules. Moreover, the phenotypes of T cell-induced DC subsets are maintained after subsequent stimulation with a panel of TLR agonists, suggesting that T(H)-derived signals outweigh downstream TLR signals in their influence on DC function. These findings indicate that T(H) cells govern the formation and function of specialized DC subsets.

A 74-year-old Iranian-born man initially presented with a penetrating atherosclerotic ulcer of the descending thoracic aorta. He underwent endovascular stenting of the lesion, but later presented with recurrent back pain and fever. He was then diagnosed with brucellosis and started on antimicrobial therapy, including 2 weeks of parenteral gentamicin and two oral agents that were poorly tolerated. Two years later he presented with fever, recurrent back pain, and new hemoptysis. He underwent successful resection of the descending thoracic aorta with in situ interposition graft reinforced with an omental wrap. Ten months postoperatively, the patient remains on lifelong suppressive antimicrobial therapy with ciprofloxacin and rifampin, without any sign of infection. No similar case has been previously reported in the English literature., (2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objective: Microvascular reconstruction is often limited by the availability and length of the pedicle. The harvesting of autologous vein grafts adds morbidity and may not provide a good match. Expanded polytetrafluoroethylene (ePTFE) grafts have been used routinely in macrovascular surgery. However, there are no conclusive data on the performance of small-diameter PTFE grafts for pedicle lengthening in free flaps in a low-pressure situation. In this study, we evaluated the efficacy of 3-mm diameter stretch ePTFE grafts to lengthen the venous pedicle of a free flap., Methods: Fifteen male New Zealand white rabbits were operated on under sterile conditions. Using an operating microscope, an epigastric flap was raised and the pedicle was exposed and dissected to its origin from the superficial femoral vessels. A segment of the vein of 1 cm to 3 cm was replaced with a stretch ePTFE graft. Microsurgical anastomoses were performed using 9-0 nylon sutures. Four weeks postoperatively, the flaps were raised again with the pedicles re-explored. The graft was then removed and examined histologically., Results: All the grafts demonstrated immediate patency. There were no cases of flap loss on the control side at 4 weeks postoperatively. When re-explored, the patent ePTFE grafts appeared to be covered by connective tissue. Light microscopy showed neoendothelialization with fibrovascular in growth., Conclusion: From this study, we can conclude that 3-mm diameter stretch ePTFE grafts can be used successfully as an alternative to bridging autologous vein grafts in free-flap pedicles.

We have examined the relationships between percentage of body fat (PBF) and risk factors for cardiovascular disease and insulin resistance and how good body mass index (BMI) and other anthropometric measures are as indices of obesity. High PBF levels were associated with increased risk of cardiovascular disease and insulin resistance. The World Health Organization BMI of 30 kg/m(2) for obesity has low sensitivity, 6.7% and 13.4% for men and women, respectively. For every obese man and woman identified, 6.7 and 1.76 times nonobese men and women, respectively, will be misclassified as obese. With the locally established BMI cutoff point for obesity of 27 kg/m(2) for men and 25 kg/m(2) for women, the sensitivity was improved to 46.7% and 60.8%, respectively. For every obese man and woman identified, 3.76 and 1.64 times nonobese men and women, respectively, will be misclassified as obese. None of the other anthropometric indices was better than the locally established BMIs. We showed that the BMIs for obesity for our local men and women are different. These BMIs were most precise among all indices studied. However, they still lead to high false-positive rates. For more effective management of the problem of obesity, we need to develop more precise, simple, and cost-effective methods for the measurement of PBF.

Objective: This study aimed to report the long-term outcomes of patients treated with an antibiotic drug combination for Bartonella henselae neuroretinitis., Design: The study design was a retrospective case series., Participants: Seven consecutive patients with neuroretinitis and cat scratch disease participated., Interventions: Patients underwent medical and ophthalmic evaluations. Blood cultures were obtained, and B. henselae antibody titers were measured. Tuberculosis, Lyme, toxoplasmosis, syphilis, and sarcoidosis were excluded. Patients received oral doxycycline 100 mg and rifampin 300 mg twice daily for 4 to 6 weeks and were observed for an average of 16 months (range, 10-24 months). Formal electrophysiologic testing was performed in three patients after resolution of neuroretinitis., Main Outcome Measures: The changes in ocular inflammation and visual function associated with treatment were recorded. Follow-up examinations and electrophysiologic testing documented sequelae., Results: Patients presented following cat exposure with fever, malaise, and blurred vision. Decreased visual acuity (ranging from 20/40 to counting fingers) frequently was associated with dyschromatopsia and afferent pupillary defects. Ophthalmoscopic analysis showed signs of neuroretinitis, including nerve fiber layer hemorrhages, cotton-wool spots, multiple discrete lesions in the deep retina, and stellate macular exudates. B. henselae infection was confirmed with positive blood cultures or elevated immunofluorescent antibody titers or both. Therapy appeared to promote resolution of neuroretinitis, restoration of visual acuity, and clearance of bacteremia. After 1 to 2 years, two eyes had residual disc pallor, afferent pupillary defects, retinal pigmentary changes, and mildly decreased visual acuity. Electrophysiologic studies showed that when compared to the fellow eye, affected eyes had subnormal contrast sensitivity, abnormal color vision, and abnormal visually evoked potentials. Conversely, electroretinograms were normal in all subjects., Conclusions: B. henselae is a cause of neuroretinitis in cat scratch disease. Compared to historic cases, doxycycline and rifampin appeared to shorten the course of disease and hasten visual recovery. Long-term prognosis is good, but some individuals may acquire a mild postinfectious optic neuropathy.

A 12-yr-old Guamanian girl presented with seven premolars displaying dens evaginatus. The pulp of one tooth was necrotic secondary to fracture of the evagination. Calcium hydroxide treatment was used to induce closure of this root apex, and subsequent routine canal obturation resulted in clinical success. Three teeth had fractured evaginations and compromised coronal pulps, but the radicular pulp tissue was vital. Coronal calcium hydroxide pulpotomy procedures were performed, and root development continued on all three teeth. In one of these teeth, endodontic treatment was completed, and in the other two the radicular pulp remained vital. Three teeth had intact evaginations and vital pulps. In an attempt to protect these evaginations from trauma, composite reinforcements were placed around the evaginations. These pulps remained vital and the roots completed normal development. Early diagnosis and treatment should be sought in cases of dens evaginatus to provide the greatest opportunity for complete root development.