We present a low-temperature (68−70 °C) synthesis of green light-emitting, trioctylphosphine oxide-capped magic-sized CdSe nanoclusters from the reaction of trioctylphosphine oxide−cadmium acetate precursors with trioctylphosphine selenide. We observed continuous growth of these magic-sized nanoclusters, which displayed a first absorption peak at 422 nm and broad luminescence covering the entire visible region. The diameter of the nanoclusters determined by transmission electron microscopic measurement was ∼1.8 nm. Powder Xray diffraction analysis showed a sharp peak at low angle (2θ = 5.3°), confirming the formation of ultrasmall, magic-sized nanoclusters. The nanocluster formation was also studied using different purities of trioctylphosphine oxide. The synthetic protocol was extended to the preparation of oleylamine-, ethylphosphonic acid-, lauric acid-, and trioctylamine-stabilized magic-sized CdSe nanoclusters. Importantly, the investigation showed that the nature of the cadmium precursors plays a crucial role in the nanocluster growth mechanism. The applicability of the trioctylphosphine oxide-capped nanoclusters was further investigated through a ligand exchange reaction with oleylamine, which displayed an extremely narrow absorption peak at 415 nm (full width at half-maximum of 14 nm) and a band edge emission peak at 456 nm with a shoulder at 438 nm.

Our food systems depend on complex interactions between farmers and food producers, local and federal governments, and consumers. Underlying these interactions are economic, environmental, and societal factors that can impact the types of food available, access to food, affordability, and food safety. The recent SARS‐CoV‐2 global pandemic has affected multiple aspects of our food systems, from federal governments’ decisions to limit food exports, to the ability of government agencies to inspect food and facilities to the ability of consumers to dine at restaurants. It has also provided opportunities for societies to take a close look at the vulnerabilities in our food systems and reinvent them to be more robust and resilient. For the most part, how these changes ultimately affect the safety and accessibility of food around the world remains to be seen.

With the increased volatility of feed prices, dairy farm managers are no longer concerned with managing only milk price volatility, but are considering the adoption of risk management programs that address income over feed cost (IOFC) margin risk. Successful margin risk management should be founded on an understanding of the behavior of IOFC margins. To that end, we have constructed forward IOFC margins using Class III milk, corn, and soybean meal futures prices. We focus on the characteristics of the term structure of forward IOFC margins, that is, the sequence of forward margins for consecutive calendar months, all observed on the same trading day. What is apparent from the shapes of these term structures is that both in times when margins were exceptionally high and in times when they were disastrously low, market participants expected that a reversal back to average margin levels would not come quickly, but rather would take up to 9 mo. Slopes of the forward margin term structure before and after most of the major swings in IOFC indicate these shocks were mostly unanticipated, whereas the time needed for recovery to normal margin levels was successfully predicted. This suggests that IOFC margins may exhibit slow mean-reverting, rather than predictable cyclical behavior, as is often suggested in the popular press. This finding can be exploited to design a successful catastrophic risk management program by initiating protection at 9 to 12 mo before futures contract maturity. As a case study, we analyzed risk management strategies for managing IOFC margins that used Livestock Gross Margin for Dairy Cattle insurance contracts and created 2 farm profiles. The first one represents dairy farms that grow most of their feed, whereas the second profile is designed to capture the risk exposure of dairy farms that purchase all their dairy herd, dry cow, and heifer feed. Our case study of this program encompasses the 2009 period, which was characterized by exceptionally poor IOFC margin conditions. We analyzed the dynamics of realized IOFC margins in 2009 under 4 different risk management strategies and found that optimal strategies that were founded on the principles delineated above succeeded in reducing the decline in IOFC margins in 2009 by 93% for the Home-Feed profile and by 47% for the Market-Feed profile, and they performed substantially better than alternative strategies suggested by earlier literature.

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