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The increasing demand for soilless media, sustainability issues with peatmoss, and increasing cost of peatmoss have prompted studies of more environmentally friendly and less expensive substitutes. Biochar, a lightweight black carbon material produced by the pyrolysis of biomass, has gained popularity as a soilless media supplement. The objective of this study was to evaluate Eastern red cedar (ERC) biochar as a supplement to soilless media for the production of chrysanthemum and ornamental kale. Treatments included ERC biochar produced at three different temperature ranges of 300 to 350 °C, 400 to 450 °C, and 500 to 550 °C that were applied at 25%, 50%, and 75% v/v plus a control (100% v/v of standard commercial mix). Additionally, ERC bark was applied at the same rate as biochar. The 300 to 350 °C and 400 to 450 °C temperature ranges increased the bulk density of the media, whereas total porosity was greatest with just bark. Regarding the physical properties of the media, in general, the 75% v/v supplementation rate of ERC bark or biochar at any temperature increased air porosity but decreased the water holding capacity, except for the water holding capacity at 500 to 550 °C. As the biochar production temperature increased, so did the pH and electrical conductivity (EC), whereas volatile matter decreased. Plant height, width, shoot dry weight, root dry weight, number of flowers (chrysanthemum only), flower diameter, and water use efficiency were greatest with the 100% v/v soilless media for both species. In general, chrysanthemum plants grown with 25% v/v biochar supplementation or bark had similar height, width, and shoot dry weight at any temperature compared with those grown with the 100% v/v soilless media. For ornamental kale, the 25% v/v 400 to 450 °C biochar supplementation showed plant height and water use efficiency similar to those of the 100% v/v soilless media. In general, 25% ERC bark performed similar to 25% v/v and 50% v/v biochar at any temperature for plant width, shoot dry weight, root dry weight, water use efficiency, and root-to-shoot ratio. The media nutrient content and EC were greater with 100% v/v soilless media and a lower rate (25% v/v) of ERC bark and biochar than with higher rates. The higher levels of biochar were harmful and reduced the ornamental kale growth and quality. These results suggest that supplemented soilless media with lower rates (25% v/v) of ERC biochar could be recommended for chrysanthemum, but that less than 25% v/v may be necessary for ornamental kale.

Multi-principal element alloys (MPEAs) are a new class of alloys that consist of many principal elements randomly distributed on a crystal lattice. The random presence of many elements lends large variations in the point defect formation and migration energies even within a given alloy composition. Compounded by the fact that there could be exponentially large number of MPEA compositions, there is a major computational challenge to capture complete point-defect energy phase-space in MPEAs. In this work, we present a machine learning based framework in which the point defect energies in MPEAs are predicted from a database of their constituent binary alloys. We demonstrate predictions of vacancy migration and formation energies in face centered cubic ternary, quaternary and quinary alloys in Ni-Fe-Cr-Co-Cu system. A key benefit of building this framework based on the database of binary alloys is that it enables defect-energy predictions in alloy compositions that may be unearthed in future. Furthermore, the methodology enables identifying the impact of a given alloying element on the defect energies thereby enabling design of alloys with tailored defect properties.

Background: The Codman-Hakim Programmable Valve is widely used in shunting hydrocephalus and other conditions., Object: To establish an accurate valve verification system for the Codman-Hakim programmable valve that does not require radiographic exposure., Methods: Prospective clinical trial tested a new valve verification system at 9 research sites., Results: The Valve Programming and Verification System allowed us to establish the valve setting in 62% of subjects with a programmable valve., Conclusion: The Valve Programming and Verification System avoids radiation exposure, is cost-effective, and time efficient for the patient and provider. In approximately one third of subjects, those in whom "adjustment complete" is not achieved, cranial radiographs are still needed.

Objective: This retrospective study examined whether changes in ventricular volume correspond with changes in adjustable valve pressure settings in a cohort of patients who received shunts to treat idiopathic normal pressure hydrocephalus. We also examined whether these pressure-volume curves and other patient variables would co-occur with a positive clinical response to shunting., Methods: We selected 51 patients diagnosed with idiopathic normal pressure hydrocephalus who had undergone implantation of a Codman Hakim programmable valve (Medos S.A., Le Locle, Switzerland). Clinical data were gathered from the patients' records and clinical notes by an investigator blinded to patients' ventricular volumes. Ventricular volume was measured using 3D Slicer, an image analysis and interactive visualization software package developed and maintained at the Surgical Planning Laboratory at Brigham and Women's Hospital., Results: Eighty-six percent of patients with gait disturbance at presentation showed improvement of this symptom, 70% experienced improvement in incontinence, and 69% experienced improvement in dementia. For the group showing 100% clinical improvement, the correlation coefficient of average changes in valve pressure over time (delta P/delta T) and average changes in ventricular volume over time (delta V/delta T) were high at 0.843 (P < 0.05). For the group experiencing no or only partial improvement, the correlation coefficient was 0.257 (P = 0.32), indicating no correlation between average delta V/delta T and average delta P/delta T for each patient., Conclusion: This was a carefully analyzed modeling study of idiopathic normal pressure hydrocephalus treatment made possible only by adjustable valve technology. With careful volumetric analysis, we found that changes in ventricular volume correlated with adjustments in valve pressure settings for those patients who improved clinically after shunting. This suggests that positive clinical responders retained parenchymal elasticity, emphasizing the importance of dynamic changes in this cohort.

This article discusses a programmable ventricular shunt valve system used to treat hydrocephalus. With this system, valve pressure can be ascertained easily with plain-film radiographs, thus avoiding complications associated with inappropriate pressures. The authors describe the shunt's design and techniques for imaging it, present illustrative cases and outline a strategy for coordinating the care of patients with these shunts.

Unlabelled: We have initiated a study in which patients suspected of having primary gliomas are given a single intracerebral injection of the thymidine analog 5-[123I]iodo-2'-deoxyuridine ([123I]IUdR). The purpose of the study is to determine the biodistribution of the radiopharmaceutical and to calculate dose estimates to the tumor and normal tissues., Methods: A patient with a cystic glioma was injected with [123I]IUdR. Whole-body scans and brain scans were obtained at various times after injection, and blood, urine and stools were collected and assayed for radioactivity to assess its biodistribution and clearance., Results: Scintigraphic imaging demonstrated that the distribution of radiolabeled IUdR was mainly confined to the tumor (injection site), stomach and bladder. Disappearance from the tumor site and blood clearance were delayed probably due to collection in the cystic lesion. Eighty percent of the injected dose was recovered in the urine., Conclusion: The pharmacokinetics of [123I]IUdR locoregionally administered to a human glioma in situ resembled those observed in a rat glioma model where administration of the radiopharmaceutical radiolabeled with the Auger electron emitter 125I was therapeutically effective.

Cerebrospinal fluid shunting is an important method of treating hydrocephalus. It sometimes has been difficult to achieve the optimum CSF pressure and ventricular size after shunt placement. Hydraulic and mechanical mismatching may occur, creating either overdrainage, as manifested by slit ventricle syndrome and/or subdural hygromas; or underdrainage, as manifested by a failure of the ventricles to change in size, with persistence of symptoms. A variable pressure valve (Codman-Medos Programmable Hakim valve system) has been developed to allow non-invasive increase or decrease in cerebrospinal fluid pressure in differentials of 10 mm of water within a range of 30-200 mm of water. This allows the neurosurgeon to adjust the pressure to the patient's particular clinical needs at any given moment. As part of a pilot study of the valve's safety, 13 patients in this center were treated with this programmable shunting system from October 1991 to January 1993. Twelve patients were over age 18 and one was younger than this. Six patients had previously been shunted with other valve systems, and the remaining seven had never been shunted before. The etiology of hydrocephalus included idiopathic normal pressure hydrocephalus (6 patients), aqueductal stenosis (3 patients), Chiari malformation (2 patients), meningitis (1 patient), and unknown etiology (1 patient). This paper describes the use of this valve in five illustrative cases; slit ventricle syndrome in an adult, chronic ventriculomegaly with aqueductal stenosis (2 cases), and idiopathic normal pressure hydrocephalus (2 cases). This programmable valve has been particularly useful in gradually decreasing ventricle size in idiopathic normal pressure hydrocephalus.(ABSTRACT TRUNCATED AT 250 WORDS)