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Dr Deborah Birx, the White House Coronavirus Task Force coordinator, told NBC News on "Meet the Press"that "[T]he U S needs a 'breakthrough' in coronavirus testing to help screen Americans and get a more accurate picture of the virus' spread "We have been involved with biopathogen detection since the 2001 anthrax attacks and were the first to detect anthrax in real-time A variation on the laser spectroscopic techniques we developed for the rapid detection of anthrax can be applied to detect the Severe Acute Respiratory Syndrome-Corona Virus-2 (SARS-CoV-2 virus) In addition to detecting a single virus, this technique allows us to read its surface protein structure In particular, we have been conducting research based on a variety of quantum optical approaches aimed at improving our ability to detect Corona Virus Disease-2019 (COVID-19) viral infection Indeed, the detection of a small concentration of antibodies, after an infection has passed, is a challenging problem Likewise, the early detection of disease, even before a detectible antibody population has been established, is very important Our team is researching both aspects of this problem The paper is written to stimulate the interest of both physical and biological scientists in this important problem It is thus written as a combination of tutorial (review) and future work (preview) We join Prof Federico Capasso and Editor Dennis Couwenberg in expressing our appreciation to all those working so heroically on all aspects of the COVID-19 problem And we thank Drs Capasso and Couwenberg for their invitation to write this paper © 2020 Navid Rajil et al , published by De Gruyter, Berlin/Boston 2020

FRET is ascribed to the spectral overlapping of upconversion luminescence and the absorption of AuNPs. This experiment enables early-stage coronavirus detection. The results show a sensitivity of 100 fM for the detection of COVID-19 DNA.

Flight velocity measurement is an important aspect of insect research that can aid insect identification and facilitate studies and monitoring of insect movements. We propose a novel scheme for the 1-D flight velocity measurement of insects, based on a near-IR Scheimpflug lidar system. We implement this new technique and apply it to study insects at the Salter Research Farm, Robertson County, Texas. The resolution property perpendicular to the probing direction of the Scheimpflug lidar system is explored and reveals the capability of retrieving the velocity component normal to the probing direction of insects passing through the field of view of our system. We observe a shift in wingbeat frequency, which indicates the presence of new insect species during the multi-day measurement. The study on 1-D flight velocity reveals a net directional movement of insects, providing supportive evidence of the arrival of a new species.

Multi-color fluorescent nanodiamonds (FNDs) containing a variety of color centers are promising fluorescent markers for biomedical applications. Compared to colloidal quantum dots and organic dyes, FNDs have the advantage of lower toxicity, exceptional chemical stability, and better photostability. They can be surface functionalized by techniques similar to those used for other nanoparticles. They exhibit a variety of emission wavelengths from visible to near infrared, with narrow or broad bandwidths depending on their color centers. In addition, some color centers can detect changes in magnetic fields, electric fields, and temperature. In this article review, we will discuss the current trends in FND’s development, including comparison to the early development of quantum dots. We will also highlight some of the latest advances in fabrication, as well as demonstrations of their use in bioimaging and biosensing.

Fluorescent nanodiamonds (FNDs) have attracted recent interest for biological applications owing to their biocompatibility and photostability (absence of photoblinking and bleaching). For optical thermometry, nitrogen-vacancy (NV) color centers and silicon-vacancy color centers in diamonds have demonstrated potential, where the NV has the highest sensitivity. However, NV is often excited with green light, which can cause heating and photodamage to tissues, as well as autofluorescence that decreases sensitivity. To overcome these limitations, we report temperature sensing using NV centers excited by deep red light (660 nm), plus another color center that can be excited with NIR light; the nickel (Ni) complex. The NV center measures temperature using diamond lattice expansion while the Ni complex measures temperature using phonon sideband strength.

Luminescent nanothermometry is a powerful tool that can precisely monitor temperature changes in animal embryos. Among the most sensitive nanoluminescent temperature sensors are fluorescent nanodiamonds (FNDs), having nitrogen-vacancy color centers, and lanthanide-ion-doped upconversion nanoparticles (UCNPs). Here, we investigate their use as nanothermometers inside bovine embryos. The motivation for using both FNDs and UCNPs to measure temperature is to avoid the question of sensor confusion by the local cellular environment. Specifically, by simultaneously measuring temperature using two different modalities having different physics, it is possible to greatly improve the measurement confidence, thereby directly addressing the recent controversy surrounding temperature measurements in living organisms.

Blood glucose monitoring is essential to avoid the unwanted consequences of glucose level fluctuations. Optical monitors are of special interest because they can be non-invasive. Among optical glucose sensors, fluorescent upconversion nanoparticles (UCNPs) have the advantage of good photostability, low toxicity, and exceptional autofluorescence suppression. However, to sense glucose, UCNPs normally need surface functionalization, and this can be easily affected by other factors in biological systems, and may also affect their ability for real-time sensing of both increasing and decreasing glucose levels. Here, we report YVO4 : Yb3+, Er3+@Nd3+ core/shell UCNPs with Nd and Yb shell and GdVO4 : Yb3+, Er3+@Nd3+ core/shell UCNPs with Nd and Yb shell that show sensitive, reversible, and selective optical glucose detection without the need for any surface functionalization or modifications.

Purpose To determine the biomechanical strength of Achilles tendon allografts with 2 different bone plug configurations as prepared for arthroscopic posterior cruciate ligament reconstruction when fixed as tibial inlay constructs. Methods Nine matched pairs of cadaveric tibias were reconstructed by a standardized tibial inlay technique by use of either a cylindrical bone plug (12 mm in diameter) or a figure-of-8 bone plug (12 × 18 mm). Constructs were subjected to cyclic tensile loading followed by load to failure. The statistical analysis consisted of paired t tests with significance set at P Results No significant differences were found in yield load, ultimate load, stiffness, load at 5 mm, and total cyclic displacement between the groups. Although both constructs showed equivalent biomechanical properties, the tendons of the cylindrical bone plugs failed predominantly by shear off the bone compared with the figure-of-8 plugs, which failed by the sutures tearing through the tibial plateau. Conclusions Tibial constructs with cylindrical and figure-of-8 bone plugs as prepared for use in arthroscopic posterior cruciate ligament reconstruction have comparable immediate biomechanical stability when fixed by a tibial inlay technique in a cadaveric model. Clinical Relevance Cylindrical and figure-of-8 bone plugs have comparable immediate biomechanical stability when fixed by a tibial inlay method, with the cylindrical technique being potentially technically easier to perform.

Media education curricula has had to address significant changes in students experiences of media resulting in a void for disadvantaged youth in terms of exposure to arts and technology. In this study we give an overview of the development of media curricula from an international perspective as it pertains to the intersection of art, education, and technology through emerging video technologies. The digital storytelling strategy using table top video addresses the new developments and continuing dilemmas of media education in secondary education. This digital video offers unprecedented possibilities for student's creative production while addressing key issues in decision making skills. Students collaborated on the educational objectives through role-plays and real decision-making scenarios. The literacy barrier for disadvantaged youth was addressed in the digital story collaborations and our experience suggests this strategy is worthy of consideration by teachers. Finally, we provide a “how-to” guide for the digital storytelling with tabletop video, thus providing the capacity to make learning more personal, meaningful, and collaborative in secondary education.

The effect of a single local injection of long acting corticosteroid on the healing of acute rat medial collateral ligament injuries was studied. The medial collateral ligaments of 81 adult female rats were exposed surgically. In 32 rats, the ligament was transected sharply, the overlying muscle was closed, and a human equivalent dose of dexamethasone was injected under the muscle layer, bathing the injured ligament. The identical operation with no corticosteroid injection was done in 32 additional rats: in the remaining 17 animals, the incision was closed without ligament transection or injection. The rats were divided into 3 groups of 25. Each group consisted of 10 rats that were injected, 10 that were not injected, and 5 that underwent sham operations. One group was euthanized 6 days after surgery, 1 group after 10 days, and 1 group after 20 days. Histologic evaluation and biomechanical testing were performed for each subgroup. A cellular pathologist examined a smaller group of 6 rats (2 from each group) for histologic changes 40 days after surgery. No histologic differences were noted between the injected and noninjected ligaments 6, 10, or 20 days after injury. At 40 days, the injected specimens showed a slightly more mature crimp pattern than the noninjected specimens. Mechanical testing demonstrated no significant difference in ultimate load or ultimate stress between the injected and noninjected groups. There were no detrimental effects of a single dose administration of dexamethasone on the histologic appearance or biomechanical strength of healing rat medial collateral ligaments.

The treatment of posterior cruciate ligament injuries sparks debate in the field of sports medicine. Surgeons argue about the ideal technique for reconstruction (tibial inlay or transtibial) and the optimal graft design (single-bundle or double-bundle). We present a novel all-arthroscopic tibial inlay technique using a bifid bone-patellar tendon-bone allograft. Advantages of our technique include avoidance of the killer turn associated with the transtibial technique and restoration of biomechanical stability through bony fixation of the tibial inlay. In addition, our technique can be performed arthrosopically without the need for a posterior incision and capsulotomy. Our graft also restores the double-bundle anatomy of the native posterior cruciate ligament, which may improve stability more effectively than single-bundle techniques. With cadaveric studies, we have demonstrated that our technique restores stability as effectively as the traditional open tibial inlay technique. Results from our early experience are encouraging, and longer-term follow-up is in progress.

The treatment of posterior cruciate ligament injuries remains controversial. There is no consensus on the ideal technique for reconstruction or the optimal graft design. Specifically, there is intense debate about which technique is superior: the open tibial inlay technique or the transtibial arthroscopic technique. We present a novel all-arthroscopic tibial inlay technique using a bifid bone–patellar tendon–bone allograft. This technique offers the advantages of the open tibial inlay technique, including avoidance of the killer turn and restoration of biomechanical stability. Furthermore, this technique is completely arthroscopic and therefore avoids the morbidity of the open tibial inlay technique from the posterior incision and capsulotomy. Our technique also avoids the need for repositioning of the patient intraoperatively. Our technique recreates the double-bundle anatomy of the posterior cruciate ligament and provides bony fixation on both tibial and femoral sides. Our cadaveric studies have shown that our technique restores stability as effectively as the traditional open tibial inlay technique. Early results in our first 11 cases are promising.

The culture of marine invertebrates, collec- Williams). Previous economic studies involving tively termed mariculture, has received much penaeid shrimp mariculture, although directed attention as a new and potentially lucrative toward an immediate need and research goal, industry. Much research has been devoted to have failed to consolidate biological, economic, molluscs (oysters, clams, and mussels) and and engineering relationships and principles crustaceans (shrimp, crawfish, crabs, and lob- into a comprehensive model capable of sters) (Bardach, Ryther, and McLarney). In performing analyses on an unlimited number particular, effort has been directed to the de- of system designs and a continuum range of velopment of a technologically and commer- facility sizes. cially feasible penaeid shrimp mariculture Computerized models designed for applicascheme (Broom; Mock and Murphy; Neal and tion in technological assessment and determinLatapie; Parker and Conte; Wheeler). Results ing direction of future research in aquaculture of extensive research efforts show promise have been developed for other systems (Allen that the technological feasibility of penaeid and Johnston; Polovina; Schurr, Allen, and shrimp farming in Gulf coastal regions of the Botsford). Though biologically oriented in United States is near to being a reality. terms of the output generated and audiences Before significant commercial investment in addressed, these models demonstrate a clear shrimp mariculture will be realized, however, step foward in analytical power in the direction economic relationships in addition to technical of assessing the status of economic feasibility. considerations must be better understood. In- Therefore, considering the purposes, applicavestors will initially want to know the vital tions, and limitations of previous modeling biological and environmental elements of a studies in aquaculture and the status of the shrimp culture system and how variability in industry, we see a distinct need for a modeling those elements affects production. Investors tool which will consolidate biological, economic, will also want to know how much control can and engineering relationships and principles. A be exercised over these critical elements and at model of this scope is needed to provide a what cost. For penaeid shrimp mariculture to framework applicable to most land-based maribecome an attractive commercial investment, culture operations. The more extensive analythese questions must be answered and the sis of this type of model will aid the potential potential economic feasibility of such opera- mariculturist (as well as creditors) in allocating tions must be established and readily de- financial resources and assessing investment monstrable to potential investors and creditors opportunities. More specifically, because during their decision-making process. shrimp mariculture is a growing new investEconomic, investment, and feasibility ment opportunity with high risk, economies of analyses have been performed on a variety of size need to be identified. That information will aquacultural systems other than penaeid enable an investor or creditor to identify the shrimp mariculture (Gibson and Wang; size of system that captures most of the econoHerrick and Baldwin; MacDonald, Meade, and mies of size and thus to keep risk capital as low Gates; Roberts and Bauer; Shang; Shang and as possible. Like previous modeling efforts, Fujimura; Smith). Studies of shrimp maricul- this type of model will also provide guidelines ture have been limited to itemizing fixed and for the direction of future research and assessvariable costs and calculating per units costs ment of advancing technology. of production for a given system or limited We describe the development of a bio-ecorange of system sizes. Financial analyses have nomic-engineering (BEE) model for penaeid been performed on given hypothetical opera- shrimp mariculture and its application to a tions defined by a rigid set of assumptions specific system. The tool is introduced in pri(Anderson and Tabb; Phillips and Gillespie; marily an application context. 1

Computer codes for the simulation of ion beams and Laplace fields have been employed for the analysis of ion implanter deflection systems. As implanter energies have increased to over 400 kV the deflection systems needed to scan the beam over ever larger wafers with more stringent implant uniformity requirements have become rather large and difficult to design. The computer codes have permitted the optimization of these systems to minimize both the size and distortions while maximizing the deflections obtained. The simulations have led to the design of optimized deflection systems utilizing straight or curved electrodes which are shorter and in most cases easier to manufacture. Design iterations can be evaluated in hours on the computer rather than weeks required for the precision laboratory testing to obtain equivalent information.

This paper will describe a new dosimetry system which has been designed for use on Varian dual end station serial process ion implanters. This new dosimetry system employs a unique approach to the use of classical Faradays to measure ion dose on a wafer. This unique approach allows significant improvements in vacuum pumping conductance away from the target wafer, the removal of potential current leakage paths into and out of the Faraday system, improvements in dose uniformity and dose repeatability, while concurrently reducing the complexity of the design. Wafer process data will be emphasized to demonstrate improvements in dose uniformity and repeatability, and to support the conclusion that this new dosimetry design will meet all requirements of VLSI processing.