3,401 research outputs found
The Effects of Possible Contamination on the Radiocarbon Dating of the Dead Sea Scrolls II: Empirical Methods to Remove Castor Oil and Suggestions for Redating
No full textWhile kept at the Rockefeller Museum in East Jerusalem, many Dead Sea Scroll fragments were exposed to castor oil by the original team of editors in the course of cleaning the parchments. Castor oil must be regarded as a serious contaminant in relation to radiocarbon dating. If modern castor oil is present and is not removed prior to dating, the 14C dates will be skewed artificially towards modern values. Earlier, it was shown that the standard AAA pretreatment procedure used in the 2 previous studies dating Dead Sea Scroll samples is not capable of removing castor oil from parchment samples. In the present work, we show that it is unlikely that castor oil reacts with the amino acids of the parchment proteins, a finding which leaves open the possibility of devising a cleaning method that can effectively remove castor oil. We then present 3 different pretreatment protocols designed to effectively remove castor oil from parchment samples. These involve 3 different cleaning techniques: extraction with supercritical CO2, ultrasound cleaning, and Soxhlet extraction—each with their own advantages and disadvantages. Our data show that the protocol involving Soxhlet extraction is the best suited for the purpose of decontaminating the Dead Sea Scrolls, and we recommend that this protocol be used in further attempts to 14C date the Dead Sea Scrolls. If such an attempt is decided on by the proper authorities, we propose a list of Scroll texts, which we suggest be redated in order to validate the 14C dates done earlier.
A case of accidental Ricin poisoning
No full textA case report of accidental, mild ricin poisoning by ingestion of ten Castor beans by a 70 year old man. The clinical presentation is followed by a discussion about the toxicity of ricin, its use and misuse and the contrast between the toxicity of pure ricin and the ingestion of castor beans. Management of castor bean poisoning is also discussed.peer-reviewe
Selectivity of pre and postemergence herbicides in single or combined applications in castor crop.
No full textOne of the main challenges in castor crop (Ricinus communis L.) production is efficient weed management mainly due to limited options of selective herbicides. This study evaluated the selectivity of herbicides applied alone or in combination in pre- and postemergence applications in castor crop. Two field experiments were carried out under irrigation conditions in a semi-arid region of Northeast Brazil. It was found that the visual symptoms of phytointoxication of the herbicides used on castor were mild in both experiments. Consequently, there were no significant interferences on plant height, number of racemes, and grain (seed) yield. Pre-emergence applications (g ha−1) of trifluralin (1800), pendimethalin (1500), clomazone (750), clomazone + trifluralin (750 + 1800), and clomazone + pendimethalin (750 + 1500) followed by chlorimuron-ethyl in postemergence (15 g ha−1) are selective to castor. The application (g ha−1) of pendimethalin + clomazone (1000 + 500) in pre-emergence, associated with chlorimuron-ethyl (10 and 15), metamitron (2800 and 4200), ethoxysulfuron (60 and 80), or halosulfuron-methyl (75 and 112.5) in one or two applications in postemergence, as single or split applications, in an interval of 14 days, are selective to castor crop
Castor Dynamic Investigation
No full textDynamic behaviour of vehicles having castored wheels can be affected by wheel shimmy phenomenon, that is a self-sustained vibration of the whole castor around the steering axis. This article presents a shimmy investigation conducted on a laboratory castor characterized by low lateral stiffness; numerical models show that this characteristics leads to three different stability conditions depending on the forward velocity: at low speeds the system is unstable and the castor is affected by shimmy oscillations; then there is an intermediate speed range in which the system recovers stability; finally, above a threshold speed value, the system returns to be unstable. The experimental investigation mainly aims to compare the numerical results with the experimental ones and to define the steering damping required to stabilize the castor according to its main features
Castor
No full textMedium: etchingprintsSigned l.r., pencil "F L Griggs" ; signed and dated on plate l.r. "F L G 1927""Castor" [1984.2022.000.000], Griggs, Frederick LandseerArtist and Role: Griggs, Frederick Landseer,Extent: plate 13.5 x 12.
Reply to Israel Carmi (2002): “Are the 14C Dates of the Dead Sea Scrolls Affected by Castor Oil Contamination?”
No full textThe Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202
Nitric oxide and castor oil-induced diarrohea
No full textThe effect of NG-nitro-L-arginine methyl ester (L-NAME) on castor oil-induced diarrhea was studied in control rats and those treated with isosorbide dinitrate or isosorbide-5-mononitrate. Castor oil (2 ml) produced diarrhea that lasted at least 8 h. Pretreatment of the rats with L-NAME (1-25 mg/kg i.p.) 15 min before castor oil did not block the castor oil-induced diarrhea beyond 3 h after challenge but delayed its appearance (P < .05-.001). However, diarrhea was inhibited (P < .01-.001) during the entire 8 h if rats were treated twice with L-NAME (25 mg/kg) (15 min before and 3 h after castor oil). These findings suggest that L-NAME, once administered, loses its activity 3 h after its administration. The nitric oxide synthase substrate, L-arginine (150-600 mg/kg), reversed (P < .05-.01) the inhibitory effect of L-NAME on diarrhea induced by castor oil. This effect is enantiomer-specific because D-arginine (900 mg/kg) was without an effect. These results suggest that castor oil-induced diarrhea in rats involves the L-arginine nitric oxide pathway. This is further supported by the effect of isosorbide dinitrate (0.6-120 mg/kg) and isosorbide-5-mononitrate (0.6-120 mg/kg). When administered to castor oil-treated rats, these two nitric oxide-generating agents prevented in a dose-dependent fashion (P < .01-.001) the inhibitory effect of L-NAME (25 mg/kg)
CASTOR: an expert advisor for testability enhancement of VLSI systems
No full textDescribes CASTOR (Computer Aided System Testability OptimizeR), which is able to support CAD designers in order to produce testable and efficient VLSI designs. Expert system and object oriented techniques have been used to describe, in a homogeneous framework, different device architectures, formalized testability conditions and design for testability techniques. The CASTOR architecture is modular, and its I/O interfaces are based on the standard description language VHDL, to allow industrial exploitation and easy encapsulation in commercial CAD frameworks. CASTOR has been tested on an industrial telecommunication device. Results and figures of merit are included. The main contribution of this novel approach is the support provided by such an automatic tool to the common designer who does not have specific knowledge of testability items
Single sign-on in a growing start-up
No full textThis thesis was written to reflect and report on a project to select and implement a single sign-on identity provider at Castor EDC. Castor was in an intense growth phase from under 50 employees to more than 100 the stringent and work intensive access control procedures were proving to be non-sustainable with such a large workforce. Thus, a single sign on service was deemed necessary to improve the scalability of the business. Single sign-on, on a longer timeline, would serve as the replacement to more manual access control procedures currently in place at Castor. The research problem was to determine what advantages the streamlining of access control, and access to services would have on employee satisfaction and effectiveness. Data was gathered via questionnaires of which there were three, two sent to employees before and after implementation measuring satisfaction, as well as one sent to service owners and administrators to gauge satisfaction with the current access control procedures. Additionally, comparisons were made to the standards to which Castor complies.
Once the project was underway and the single sign-on provider was implemented to some of the more widely used tools, advantages started to become apparent to the author. Onboarding to most general tools was streamlined and at the time of writing this thesis, the provider was being integrated with more department specific, yet critical, services. Data gathered from questionnaires revealed mostly lukewarm attitudes toward the password manager previously used with mostly positive first impressions of the new single sign-on provider. According to service owners and administrators, the access control procedure at Castor is error-prone and tedious. This procedure can be streamlined, as a result of SSO implementation. Recommendations to the client include, but are not limited to, adding single sign-on support as a requirement to Castor’s supplier purchasing procedure, rewriting access control procedures to allow for the single sign-on solution to replace old procedures where applicable, and in existing services disabling form-based authentication in favour of single sign-on
Feeding behavior of lambs fed castor meal
No full textThe experiment aimed to evaluate the feeding behavior of Santa Inês lambs fed diets containing different levels of detoxified castor meal in the concentrate. Twenty-four sheep with an average body weight of 18.5± 2.26 kg, at four months of age, were distributed in a randomized complete design with four treatment and six replications. Treatments consisted of four levels of castor meal (0, 33, 67, and 100%) replacing soybean meal. Animals underwent a 15-day adaptation period and an experimental period of 84 days. The diet was composed of 60% sugarcane silage and 40% concentrate, on a dry matter basis. Animal behavior (idle, rumination, and feeding activities) were observed visually for two 24-h periods with 5-min intervals, and recorded. The number of rumination chews and the time taken to ruminate each cud per day were counted using a digital stopwatch. Dry matter (DM) intake was not affected by inclusion of castor meal in the concentrate, averaging 884.02 g day?1. The feeding activity was not affected by addition of castor meal. Rumination time increased linearly, whereas the idle and rumination times decreased linearly with addition of castor meal. Feeding time, expressed in min per kg of DM and NDF, was not influenced by the inclusion of the meal in the diet, averaging 373.3 and 880.0 min, respectively. The number of chews and the time taken to ruminate each cud were not changed by inclusion of castor meal in the diet. Feed efficiency, expressed in grams DM and NDF per hour, was not influenced by castor meal inclusion in the diet. Rumination efficiency expressed in g DM h?1 decreased, but was not affected when expressed in g NDF h?1. Total replacement of soybean meal by castor meal in the concentrate does not affect the feeding time or feed efficiency of feedlot sheep, but leads to a small reduction of their rumination efficiency. Thus, we recommend the inclusion of castor meal in sheep diets at the levels tested in this study
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