Strongly interacting fermions define the properties of complex matter at all densities, from atomic nuclei to modern solid state materials and neutron stars. Ultracold atomic Fermi gases have emerged ...as a pristine platform for the study of many-fermion systems. Here we realize a quantum gas microscope for fermionic \(^{40}\)K atoms trapped in an optical lattice, which allows one to probe strongly correlated fermions at the single atom level. We combine 3D Raman sideband cooling with high-resolution optics to simultaneously cool and image individual atoms with single lattice site resolution at a detection fidelity above \(95\%\). The imaging process leaves each atom predominantly in the 3D ground state of its lattice site, inviting the implementation of a Maxwell's demon to assemble low-entropy many-body states. Single site resolved imaging of fermions enables the direct observation of magnetic order, time resolved measurements of the spread of particle correlations, and the detection of many-fermion entanglement.
The traditional economic order quantity (EOQ) inventory model can be modified for use with just-in-time (JIT) concepts in purchasing systems not yet advanced to the ultimate level of JIT purchasing, ...where the lot size is one and material from the supplier is delivered directly to the buyer's production line. In this model, the fixed costs associated with the switch to a JIT system are treated as an investment. This is justified based on the savings generated, which can be calculated using any of several well-known techniques of investment analysis. Savings can be maximized if operating decisions are optimized so that the total cost of the inventory system is minimized. This is accomplished by modifying the traditional EOQ model so it explicitly includes the costs of the small-lot shipments that characterize JIT purchasing. The optimal quantity must be calculated based on JIT philosophy, with the number of shipments per order optimized using the model.
The exocellular α‐amylase of a strain of Aspergillus niger van Tieghem (elaborating both dextrifying and saccharifying thermophilic amylases) was purified to homogeneity. Purification was achieved by ...providing cultural conditions for the organism to preferentially synthesize α‐amylase and fractionation of the culture filtrate by DEAE‐Sephadex chromatography. Its purity was established by gel electrophoresis and confirmed by sedimentation studies. The molecular weight of the enzyme was 56,230. Its Km values on different starches, temperature and pH optima for activity and energy of activation were established. Compared to literature values for other fungal α‐amylases, this enzyme exhibited a lower energy of activation, increased tolerance to lower pH and enhanced affinity to starch, highlighting its potential industrial application. While Ag+, Pb2+, Hg+, Al3+ and EDTA inhibited the activity of the enzyme, Ca2+ enhanced its activity, apart from conferring thermal stability and lowered activation energy. The product of its action on starch were maltooligosaccharides, maltose and glucose.
Reinigung und Charakterisierung einer thermophilen α‐Amylase aus Aspergillus niger van Tieghem.
Die extrazelluläre α‐Amylase eines Stammes von Aspergillus niger van Tieghem, der sowohl dextrinierende als auch verzuckernde thermophile Amylasen hervorbringt, wurde bis zur Homogenität gereinigt. Die Reinigung wurde durch Einhalten der Kulturbedingungen zur bevorzugten Bildung von α‐Amylase sowie durch Fraktionierung des Kulturfiltrates mittels DEAE‐Sephadex‐Chromatographie bewerkstelligt. Das Molekulargewicht des Enzyms betrug 56230. Seine KM‐Werte (KM = Michaelis‐Konstante) für verschiedene Stärken, Temperatur‐ und pH‐Optima der Aktivität sowie die Aktivierungsenergie wurden bestimmt. Verglichen mit anderen Pilz‐α‐Amylasen zeigte dieses Enzym eine niedrigere Aktivierungsenergie, erhöhte Toleranz gegenüber niedrigeren pH‐Werten sowie verstärkte Affinität zu Stärke. Während Ag+, Pb2+, Hg+, Al3+ und EDTA die Aktivität des Enzyms hemmten, erhöhte Ca2+ seine Aktivität. Die Produkte seiner Einwirkung auf Stärke waren Maltooligosaccharide, Maltose und Glucose.
Two isoenzymes of amyloglucosidase, designated as AG‐I and AG‐II, elaborated exocellularly by a strain of Aspergillus niger van Tieghem, were separated and purified to homogeneity. The enzymes, ...produced in a selective medium, were separated and purified on a column of DEAE‐Sephadex A‐50. The molecular weights of AG‐I and AG‐II were found to be 69, 810 and 89,130 respectively. The two enzymes were glycoproteins and differed in their carbohydrate contents, pH and temperature stabilities and optima for activity. Their activation energies and Km values also varied. AG‐II, had a higher molecular weight, carbohydrate content, increased acid tolerance and was synthesized earlier to AG‐I (when the pH of the medium was acidic). Hg and Ag salts caused partial inhibition of their activities.
Untersuchung der beiden Amyloglucosidase‐Arten von Aspergillus niger van Tieghem.
Zwei Isoenzyme von Amyloglucosidase, bezeichnet als AG‐I und AG‐II, die extrazellular durch einen Stamm von Aspergillus niger van Tieghem gebildet werden, wurden getrennt und zur Homogenität gereinigt. Die in einem selektiven Medium produzierten Enzyme wurden auf einer Säule von DEAE‐Sephadex A‐50 getrennt und gereinigt. Die Molekulargewichte von AG‐I und AG‐II wurden mit 69 810 und 89 130 ermittelt. Die beiden Enzyme waren Glycoproteine und unterschieden sich in ihrem Kohlenhydratgehalt, in ihrer pH‐ und Temperaturstabilität sowie in ihren Aktivitätsoptima. Ihre Aktivierungsenergie und KM‐Werte (KM = Michaelis‐Konstante) unterschieden sich ebenfalls voneinander. AG‐II hatte einen höheren Kohlenhydratgehalt, eine erhöhte Säuretoleranz und wurde früher als AG‐I synthetisiert, d. h. bei saurem pH‐Wert des Mediums. Hg‐ und Ag‐Salze riefen eine teilweise Hemmung ihrer Aktivitäten hervor.
