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Waugh Simmons posted an update 1 day, 6 hours ago
Based upon careful observation on the phenotype of colony formation on 5-FOA medium by spot test, we came to an important conclusion that particular chromosomal regions harboring only non-essential genes can be categorized into three classes, i.e., essential, non-essential and intrinsically essential. Intrinsically essential region is defined as appearance of papillae after mini-chromosome loss which implicates that the region is essential but compensatable against cell lethality. Our present study indicates that prudent and multiple approaches as performed in this study are needed to judge whether a particular chromosomal region of the S. cerevisiae genome is essential, non-essential or intrinsically essential but compensatable.Great efforts have been made in dosimetry for individualizing PRRT. However, many centers do not use dosimetry and its results hardly influence treatment. A reason for that is that reliable thresholds for organs-at-risk, kidneys and bone marrow, and treatment response are lacking. The nuclear medicine community must provide solid data from large trials delivering reliable thresholds, which then help to tailor PRRT according to organ doses (in order to reduce toxicity or increase treatment activity) or tumor doses (in order to increase activity to meet the response-threshold). Otherwise, development of radionuclide therapies will be done like big pharmaceutical companies do it currently classical dose escalation studies and agreement on acceptable toxicity probabilities. Therapeutic radiopharmaceuticals will then be handled like other drugs, which on the other hand will increase availability of radionuclide therapies.Under predation threat, many species produce cues that can serve as crucial sources of information for social companions. For instance, chemical cues released when experiencing a disturbing event (i.e. ‘disturbance cues’), such as a predator chase, can lead to antipredator avoidance and increased survival for nearby individuals. These chemicals also have potential to be produced as a voluntary signal for communicating threat to others. We found evidence for this hypothesis by manipulating the shoal familiarity of guppies from populations differing in background predation risk and then presenting their disturbance cues to unfamiliar conspecifics from the same populations. Receivers from low-risk sites increased shoal cohesion and decreased area use regardless of whether the disturbance cues were produced in donor groups where members were familiar or unfamiliar with each other. However, receivers from high-risk sites showed strong antipredator reactions towards disturbance chemicals produced in familiar groups and no response towards those produced in unfamiliar groups, suggesting that donors from high-risk sites may alter the quality or quantity of their disturbance cues to influence familiar individuals to enact predator defences. Because high-risk environments strengthen guppy social networks, these environments may facilitate reliance on chemical disturbance signalling to coordinate group defences with familiar individuals.During hot weather, terrestrial animals often seek shaded thermal refugia. However, this can result in missed foraging opportunities, loss of body condition and impaired parental care. We investigated whether such costs could compromise breeding success in a widespread southern African bird the Southern Yellow-Billed Hornbill Tockus leucomelas. We predicted that hornbills might be especially vulnerable to temperature-dependant reductions in parents’ foraging capacity due to extreme asymmetry in sex-specific roles during breeding females are confined within the nest cavity for most of the nesting period and the burden of provisioning falls solely on the male during this time. We followed 50 hornbill nesting attempts in the Kalahari Desert between 2012 and 2015, collecting data on provisioning rates, adult and nestling body mass, fledging success and size of fledglings. Mean daily maximum air temperatures (Tmax) during nesting attempts ranged from 33.2 to 39.1 °C. The likelihood of successful fledging fell below 50% at mean Tmax > 35.1 °C; a threshold now regularly exceeded at our study site due to recent climate warming. Additionally, offspring fledging following the hottest nesting attempts were > 50% lighter than those fledging following the coolest. Sublethal costs of keeping cool including loss of body condition, production of poor-quality offspring and breeding failure are likely to become issues of serious conservation concern as climate change progresses; even for currently widespread species. Missed-opportunity costs associated with behavioral thermoregulation and direct sublethal costs of temperature exposure should not be overlooked as a potential threat to populations, especially in environments that are already hot.PURPOSE OF REVIEW We review advances in imaging of liver tumors, by particularly focusing on the utility of novel imaging in diagnosis and management of these lesions. RECENT FINDINGS Contrast-enhanced CT and/or MRI are currently utilized for accurate diagnosis of liver tumors, but several ongoing studies are examining the use of other advanced techniques. Novel CT (i.e., dual-energy CT and perfusion CT), MRI (diffusion-weighted imaging, MR elastography, and T1 mapping), and image processing (texture analysis and artificial intelligence-based methods) techniques have emerged and can be used for precise characterization of liver tumors, quantification of treatment responses, and prediction of overall survival rate of patients. Recent advancements in imaging of liver tumors allowed for a precise assessment of tumor features. These evolving technologies can be utilized for applying individualized treatment based on the presence of specific imaging biomarkers.PURPOSE Sexual transmission of HIV has been clinically proven to be preventable with a once-daily oral tablet; however, missed doses dramatically increase the risk of HIV infection. Long-acting subcutaneous implants do not allow the user to miss a dose. A desirable long-acting drug-eluting implant can deliver a constant amount of drug, adjust the delivered dose, and be readily manufactured. We present a long-acting, subcutaneous implant design composed of tenofovir alafenamide hemifumarate (TAF) pellets loaded in a sealed polyether urethane tube for the prevention of HIV transmission. Beta Amyloid inhibitor METHODS Implants were prepared with pressed drug pellets and extruded polyurethane tubing. In vitro release rate of implants using different pellet formulations, rate-controlling membranes, and geometries were measured. RESULTS Tenofovir alafenamide release appeared to be governed by a pseudo-steady state and followed a mass transport model of release from a cylindrical drug reservoir. Implant seal integrity was tested and confirmed using mechanical testing.