A microfluidic oligonucleotide synthesizer

De novo gene and genome synthesis enables the design of any sequence without the requirement of a pre-existing template as in traditional genetic engineering methods. The ability to mass produce synthetic genes holds great potential for biological research, but widespread availability of de novo DNA constructs is currently hampered by their high cost. In this work, we describe a microfluidic platform for parallel solid phase synthesis of oligonucleotides that can greatly reduce the cost of gene synthesis by reducing reagent consumption (by 100-fold) while maintaining a 100 pmol synthesis scale so there is no need for amplification before assembly. Sixteen oligonucleotides were synthesized in parallel on this platform and then successfully used in a ligation-mediated assembly method to generate DNA constructs 200 bp in length

Structural Credit Assignment with Coordinated Exploration

A biologically plausible method for training an Artificial Neural Network (ANN) involves treating each unit as a stochastic Reinforcement Learning (RL) agent, thereby considering the network as a team of agents. Consequently, all units can learn via REINFORCE, a local learning rule modulated by a global reward signal, which aligns more closely with biologically observed forms of synaptic plasticity. However, this learning method tends to be slow and does not scale well with the size of the network. This inefficiency arises from two factors impeding effective structural credit assignment: (i) all units independently explore the network, and (ii) a single reward is used to evaluate the actions of all units. Accordingly, methods aimed at improving structural credit assignment can generally be classified into two categories. The first category includes algorithms that enable coordinated exploration among units, such as MAP propagation. The second category encompasses algorithms that compute a more specific reward signal for each unit within the network, like Weight Maximization and its variants. In this research report, our focus is on the first category. We propose the use of Boltzmann machines or a recurrent network for coordinated exploration. We show that the negative phase, which is typically necessary to train Boltzmann machines, can be removed. The resulting learning rules are similar to the reward-modulated Hebbian learning rule. Experimental results demonstrate that coordinated exploration significantly exceeds independent exploration in training speed for multiple stochastic and discrete units based on REINFORCE, even surpassing straight-through estimator (STE) backpropagation.Comment: 17 page

Co-crystal screening of poorly water-soluble active pharmaceutical ingredients. Application of hot stage microscopy on curcumin-nicotinamide system and construction of ternary phase diagram of fenbufen-nicotinamide-water co-crystal system.

Curcumin is the major phenolic diarylheptane derivative in Curcuma longa and has been reported to possess pharmacological activities. Unfortunately this compound suffers from poor bioavailability and rapid neutral-alkaline degradation. Co-crystal of curcumin is one option under exploration, motivated by the fact that a number of active pharmaceutical ingredient (API) co-crystals with improved dissolution have recently been synthesized. Hence, co-crystallization technique highlights an alternative means to improve the performance of curcumin. Within our work evidences for a co-crystal was ascertained from DSC, Kofler hot stage screening and PXRD, and all confirmed a new crystal phase could have been formed between curcumin and a co-crystallizing agent, nicotinamide. We report that re-crystallization step essentially aids the purification of commercial curcumin, a herbal based actives. Otherwise the prevalence of a new crystal phase in solvent-mediated co-crystallization will be significantly reduced. Besides, phase diagram is an effective tool for the study of solubility behaviours in co-crystal system. In order to acquire related techniques, fenbufen, a poorly water soluble drug, was selected. The result showed the huge difference in solubility between fenbufen and nicotinamide lead to difficulty in the construction of phase diagram

U.S. Coast Guard Boat Recovery Simulation at NASA Ames Vertical Motion Simulator

The Boat Recovery Simulation was a collaboration between the U.S. Coast Guard and NASA. The experiment was conducted at the NASA Ames Vertical Motion Simulator (VMS). The goals were to (1) design a VMS experiment that can accurately simulate the motion of high sea conditions and to (2) collect data for the U.S. Coast Guard on human performance related to small boat recovery operations. The experiment setup included a software operation model designed around empirical boat position data; a replica boat section manufactured to incorporate real-world task elements; and the means to collect objective and subjective data from human participants. The VMS provided a viable testbed to assess certified U.S. Coast Guard crewmembers task performance while in motion

Economic Assessment of Food Safety Regulations: The New Approach to Meat and Poultry Inspection

USDA is now requiring all Federally inspected meat and poultry processing and slaughter plants to implement a new system called Hazard Analysis and Critical Control Points (HACCP) to reduce potentially harmful microbial pathogens in the food supply. This report finds that the benefits of the new regulations, which are the medical costs and productivity losses that are prevented when foodborne illnesses are averted, will likely exceed the costs, which include spending by firms on sanitation, temperature control, planning and training, and testing. Other, nonregulatory approaches can also improve food safety, such as providing market incentives for pathogen reduction, irradiation, and education and labeling to promote safe food handling and thorough cooking.food safety, foodborne illness, microbial pathogens, meat and poultry inspection, HACCP, cost of illness, consumer education, irradiation, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Evaluating emotional distress and health-related quality of life in patients with heart failure and their family caregivers:Testing dyadic dynamics using the Actor-Partner Interdependence Model

Purpose: 1) To compare levels of emotional symptoms and health-related quality of life between patients with heart failure and their family caregivers; and 2) to examine whether patients’ and caregivers’ emotional symptoms were associated with their own, as well as their partner’s health-related quality of life. Method: In this cross-sectional study, 41 patients-caregiver dyads (78% male patients, aged 68.6 years; and 83% female caregivers, aged 65.8 years) completed all nine dimensions of the Brief Symptom Inventory and the Minnesota Living with Heart failure Questionnaire. Dyadic data were analysed for 6 sub-scales of the Brief Symptom Inventory, using the Actor–Partner Interdependence Model. Results: There were no statistically significant differences in emotional symptoms and health-related quality of life between patients with heart failure and their caregivers. Patients’ and caregivers’ emotional symptoms were associated with their own health-related quality of life. Caregivers’ anxiety, phobic anxiety, obsession-compulsion, depression and hostility negatively influenced their partner’s (i.e. the patient’s) health-related quality of life. There were no partner effects of patients’ emotional symptoms on the health-related quality of life of caregivers. Conclusions: The results of this study suggest that patients may be particularly vulnerable to the emotional distress, i.e. thoughts, impulses and actions of their caregivers. It may be possible to improve patients’ health-related quality of life by targeting specific detrimental emotional symptoms of caregivers

Foraminiferal evidence for the intensification of the east Australia current during the LGM

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