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The integration of robotics with agriculture in a controlled or closed environment is attractive because it enables remote production of food and oxygen without siphoning valuable hours of astronaut labor. Similar techniques can also be applied to terrestrial habitats to improve food security in areas that may not be well-suited to outdoor and/or labor-intensive traditional agricultural practices. In this paper, a robotic system for plant tending is presented with reflections on results of early demonstrations. The system includes remote teleoperation capabilities, a 6-DOF robotic arm, vision system for 3D reconstruction of plants, pneumatic multi-tool changer, and custom end-effectors including an enclosure latch tool and a plant shear tool. This work is a collaborative effort between NASA Kennedy Space Center, Lockheed Martin Space, and university partners to test the technologies of autonomous plant growth systems in deep space.

The Vegetable Production System (Veggie) is a scientific payload designed to support plant growth for food production under microgravity conditions. The configuration of Veggie consists of an LED lighting system with modular rooting pillows designed to contain substrate media and time-release fertilizer. The pillows were designed to be watered passively using capillary principles but have typically been watered manually by the astronauts in low-Earth orbit (LEO). The design of Veggie allows cabin air to be drawn through the plant enclosure for thermal and humidity control and for supplying CO2 to the plants. Since its delivery to the International Space Station (ISS) in 2014, Veggie has undergone several experimental trials by various crews. Ground unit testing of Veggie was conducted during an 8-month Mars analog study in a semi-contained environment of a simulated habitat located at approximately 8,200 feet (2,500 m) elevation on the Mauna Loa volcano on the Island of Hawaii. The Hawaii Space Exploration Analog and Simulation (HI-SEAS) offered conditions (habitat, mission, communications, etc.) intended to simulate a planetary exploration mission. This paper provides data and analyses to show the prospect for optimized use of the current Veggie design for human habitats. Lessons learned during the study may provide opportunities for updating the system design and operational parameters for current Veggie experiments being conducted onboard the ISS and for payloads on future deep space missions.

Orion, the Multi-Purpose Crew Vehicle, is a key piece of the NASA human exploration architecture for beyond earth orbit (BEO). Lockheed Martin was awarded the contracts for the design, development, test, and production for Orion up through the Exploration Mission 2 (EM-2). Lockheed Martin is also working on defining the cis-lunar Proving Ground mission architecture, in partnership with NASA. In addition, Lockheed Martin is exploring the definition of Mars missions as the horizon goal to provide input to the plans for human exploration of the solar system. This paper describes an architecture to determine the feasibility of a Mars Base Camp architecture within about a decade. This architecture would involve human exploration of both Martian moons, and provide an opportunity for the crew to interact with pre-staged robotic assets on Mars. This study is a high-level assessment to identify architecture drivers and science opportunities. There are several key tenets for this architecture. For this first human interplanetary mission, system redundancy and a self-rescue capability is required. The number of system developments is minimized, and the use of the already developed systems like the Space Launch System and Orion is maximized. To minimize the number of events that could lead to the loss of the whole crew, the architecture does not require rendezvous and docking of pre-staged elements necessary for crew survival during the mission. This paper will describe the different enabling technologies required. The trajectory assumptions will be described, including the results of studies performed for the transit to Mars and return to Earth, in addition to mission design trades for the exploration of the Martian system. The transfer vehicle module design concept will be detailed. Possible science activities will be described. Study results for propulsion technology, assembly methods, and the mission campaign will also be addressed, as well as a discussion of planned forward work. The results of this architecture study will show that a near term Mars mission is compelling and feasible, and will highlight the required key systems.

Cardiac resynchronization therapy (CRT) has been introduced as a treatment for selected heart failure patients, specifically those with symptomatic heart failure, left ventricular (LV) dysfunction, and intraventricular conduction delays. CRT is delivered by use of an implanted device and leads positioned in the right atrium, right ventricle, and left ventricle. In the early stages of CRT development, researchers affixed epicardial electrodes to the left ventricle by means of subxiphoid, thoracoscopic, or major surgical procedure. Currently there are a number of transvenous LV leads available that have undergone substantial evaluation. Reports indicate that such leads can be positioned safely by cannulating the coronary sinus and inserting the lead into the venous system. The leads are reported to have acceptable pacing/sensing thresholds and complication rates. Because of individual variations in the cardiac and venous anatomy, as well as sharp angulations in the venous system, maneuverability is an important consideration in lead selection.

Introduction We reinvestigated the synthesis of [ N -methyl- 11 C]vorozole, a radiotracer for aromatase, and discovered the presence of an N -methyl isomer which was not removed in the original purification method. Herein we report the preparation and positron emission tomography (PET) studies of pure [ N -methyl- 11 C]vorozole. Methods Norvorozole was alkylated with [ 11 C]methyl iodide as previously described and also with unlabeled methyl iodide. A high-performance liquid chromatography (HPLC) method was developed to separate the regioisomers. Nuclear magnetic resonance (NMR) spectroscopy ( 13 C and 2D-nuclear Overhauser effect spectroscopy NMR) was used to identify and assign structures to the N -methylated products. Pure [ N -methyl- 11 C]vorozole and the contaminating isomer were compared by PET imaging in the baboon. Results Methylation of norvorozole resulted in a mixture of isomers (1:1:1 ratio) based on new HPLC analysis using a pentafluorophenylpropyl bonded silica column, in which vorozole coeluted one of its isomers under the original HPLC conditions. Baseline separation of the three labeled isomers was achieved. The N-3 isomer was the contaminant of vorozole, thus correcting the original assignment of isomers. PET studies of pure [ N -methyl- 11 C]vorozole with and without the contaminating N-3 isomer revealed that only [ N -methyl- 11 C]vorozole binds to aromatase. [ N -methyl- 11 C]Vorozole accumulated in all brain regions with highest accumulation in the aromatase-rich amygdala and preoptic area. Accumulation was blocked with vorozole and letrozole consistent with reports of some level of aromatase in many brain regions. Conclusions The discovery of a contaminating labeled isomer and the development of a method for isolating pure [ N -methyl- 11 C]vorozole combine to provide a new scientific tool for PET studies of the biology of aromatase and for drug research and development.

Automatic mode switching (AMS) function in dual chamber pacemakers depends on adequate detection of atrial tachyarrhythmias. There are few data on showing how intra-operative atrial signal amplititude during sinus rhythm can predict atrial tachyarrhythmias after pacemaker implantation. In 43 patients undergoing DDDR pacemaker implantation and atrioventricular nodal ablation for the treatment of drug-refractory paroxysmal atrial fibrillation, atrial sensing thresholds during sinus rhythm and during induced atrial tachyarrhythmias (24‐48 h after device implantation) were analysed. Five diVerent DDDR pacemaker systems were implanted (Chorus 7034 = , Ela Medical n=13; Meta DDDR 1254 = , Telectronics Pacing Systems n=12; Vigor DR 1230 = , Guidant n=6; Trilogy DR 2364 = , Pacesetter, n=2; Kappa DR 401 = , Medtronic USA n=10). Every patient received a steroid-eluting, screwin, bipolar atrial lead (Medtronic, Capsure-Fix 4068 = ). The mean P wave amplitude during implantation was 3·91&1·14 mV. The mean atrial sensing threshold during sinus rhythm and during all modes of induced atrial tachyarrhythmias was 3·35&1·0 mV, and 1·52&0·92 mV, respectively (P

The effect of various agents which cause cell inactivation on the growth curves and RNA synthesis rates of chinese hamster ovary (CHO) calls has been studied. Agents which are known to act on DNA cause a reduced cell growth and RNA synthesis rate. Agents with a cytoplasmic target in eucaryotic cells cause a lengthened lag-phase, followed by growth and RNA-synthesis comparable to that of the control cells. From experiments with acrylonitrile, trichloroethylene, p-tetrachlorohydroquinone, cadmium chloride, and mercury chloride it is concluded that such studies can be used as a rapid test system for preliminary information as to whether a particuliar agent primarily damages the DNA of the cell nucleus or cytoplasmic structures in CHO cells.

Aims The aim of the study was to compare the defibrillation energy requirements and the probability of successful defibrillation at multiples of the minimum defibrillation energy requirements in active pectoral implantable defibrillators with single- and dual-coil lead systems. Methods and Results Eighty-three consecutive patients undergoing implantation of an active pectoral cardioverterdefibrillator were randomized to receive a dual- or singlecoil lead system. Defibrillators of two manufacturers with a fixed tilt biphasic defibrillation waveform were used. Defibrillation energy requirements were determined using a step-down defibrillation testing protocol. According to the randomization protocol, the patients were assigned to three additional consecutive defibrillation attempts during device implantation and during pre-discharge testing of either 1·0, 1·5 or 2·0 times the determined defibrillation energy requirement. Patients presenting defibrillation energy requirements >15 J were excluded from analysis. Eighty of 83 patients (96%) completed the study protocol. Three patients were excluded due to elevated defibrillation energy requirements. The defibrillation energy requirements in the dual- and single-coil patient groups were 8·03·6 J and 8·43·7 J (ns), respectively. A comparable percentage of study patients showed defibrillation energy requirements

In about a third of cases of recurrent syncope a diagnosis cannot be established despite extensive cardiovascular and neurologic testing. In patients without underlying heart disease the sensitivity of conventional diagnostic testing is low.A 33-year-old male patient underwent implantation of a loop recorder (Reveal) after negative neurological and cardiovascular testing. One month after implantation sinus node arrest could be documented during a presyncope. The patient underwent pacemaker implantation and remains asymptomatic since then.In patients with syncope and a negative conventional diagnostic workup the implantable loop recorder is a helpful and cost-effective diagnostic tool.

We could show that both nicotinamide and N-acetylcysteine inhibit collagen induced arthritis in mice. In the present paper, using lower doses of each, we applied combinations of these two substances. We were able to confirm potentiating effects of these combinations. These results may allow new perspectives for the therapy of arthritis to emerge.

Treatment with a combination of 10 mg/kg i.p. methotrexate and 100 mg/kg i.p. nicotinamide inhibits the development of collagen II induced arthritis in male DBA/1 X B.10(4R) mice, as assessed by the arthritic index and whole blood chemiluminescence. The effect is much more pronounced than with either methotrexate or nicotinamide alone at the same concentrations. Determination of GOT and GPT levels in the blood revealed that the treatment causes no toxic side effects on the liver.

The first report about experimental investigations on the origin of the rhythms in the mammalian heart were published in 1888 by McWilliam. Similar experiments were described by Hering in several publications starting from 1900. The results led to the hypothesis of the myogenic genesis of the rhythms. However, in 1907, Hering stated that the origin of the stimulus in the mammal heart was probably a nervous function. In 1898, 1903, and 1906 Wenckebach described the function and the functional localization of the pacemaker in the heart of the intact man, and in 1906, he described the morphology of the pacemaker and its blood supply in the post mortem human heart. In the same year, Adam analyzed the localization of the "natural" pacemaker and the regions of the secondary pacemakers in the mammal heart. In 1907, Keith and Flack introduced the term "sino-auricular node". They quoted the findings of Wenckebach and Hering, and they mentioned McWilliam. A muscular connection between the right atrium and both ventricles of the mammal heart was found by Kent and by His in 1893. In 1907, Tawara called the structure of the origin of the a-v connection "atrio-ventricular node". It was, however, the scientific discovery of Tawara that the a-v pathway was connected with the muscles of the ventricles by the Purkinje fibers. He discovered that the pathway consists of muscles which are histologically divided and functionally different from the other heart muscles. It is a system of specialized muscles which conduct the stimulus for the contraction without contracting themselves.

The anti-arthritic reactivity of the IL-1 receptor antagonist IL-1ra was tested in male DBA/1xB10A(4R) mice suffering from potassium peroxochromate-induced arthritis.Inflammatory arthritis was induced in male DBA/1xB10A(4R) mice by the intraplantar application of potassium peroxochromate and was quantified by the determination of the arthritis index, whole blood chemiluminescence, serum sulfhydryls and nitric oxides. Culture supernatants of the fibroblasts were assayed spectrophotometrically for collagenase release.Overt arthritic symptoms, as measured by the arthritis index, were significantly inhibited after two intraperitoneal injections of 2 mg/kg IL-1ra. The phorbol-ester-stimulated chemiluminescent response of monocytes and polymorphonuclear leukocytes in whole murine blood, which increased 5-fold during the development of arthritis, was normalized to the level of healthy controls. The oxidation of serum sulfhydryls was inhibited by 25%, and the serum levels of nitric oxides was depressed by 40%. In vitro the IL-1-dependent induction of collagenase of rabbit synovial fibroblasts was completely suppressed in the presence of 0.4 mg/ml IL-1ra.IL-1ra may prove useful to control the consequences of enhanced free radical production in inflammatory rheumatic diseases.

Inthelastdecadesseveralinvestigatorshavesuggestedtheassociationofandrogenswithhypertension. Recently, some studies have shown that the incidence of cardiovascular diseases is increased in men with low testosterone levels, suggesting a protective role of androgens. Hypertension is one of the mostcommonproblemsinpregnancythatcomplicates5-10 %ofpregnancies.Anincreaseofmorbidity wasobservedinbabiesfrompregnantwomenwithhypertension.However,thepathogenesisremains unclearandthislimitstheabilitytopreventandtreatthispathology.Thebeneficialeffectsofandrogens for vascular system are associated with their ability to cause vasorelaxation. Inhuman vessels, this non genomiceffectofandrogensappeartobeduetoactivationoflargeconductancecalcium-activatedpotassiumchannels(BKCa)andvoltagegatedpotassiumchannels(KV)whichisinducedbycGMPincrease andaconsequentactivationofcGMP-dependentproteinkinase(PKG).Ontheotherhand,thegenomic effects of androgens concerning ionic channels are almost unknown. Our previous studies suggested that androgens increase the expression of BKCa channels and decrease expression of L-type calcium channels (LTCC). The aim of this work was to analyze the genomic effects of androgens on theexpressionofotherproteinsinvolvedintheregulationofvascularcontractility,suchassolubleguanylate cyclase (sGC), the natriuretic peptide receptor-A (NPRA) and PKG. This study also aimed to compare the expression levels of these proteins in human umbilical artery (HUA) from normotensive andhypertensivepregnantwomen.ToachievethesegoalsrealtimePCRwasperformedusingsmooth

Eine biatriale getriggerte Elektrostimulation ist eine sichere und tendenziell effektive Methode zur Reduktion der Inzidenz postoperativen Vorhofflimmerns bei Patienten nach ACVB-Operation. Die in unserer Untersuchung nicht erlangte statistische Signifikanz im Vergleich der verschiedenen Stimulationsmodi bezuglich der Inzidenz von Vorhofflimmern liegt unseres Erachtens an der zu kleinen Fallzahl der in die Untersuchung eingeschlossenen Patienten.

It is shown that p -tetrachlorohydroquinone (TCH), the metabolite of the environmental chemical pentachlorophenol (PCP), is more toxic to cultured CHO cells than PCP, and that it causes DNA single-strand breaks and/or alkali-labile sites at concentrations of 2–10 μg/ml as demonstrated by the alkaline elution technique.