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Review of 'The Necessity of Exile' by Shaul Magid ON NOVEMBER 14, A RAMALLAH-BASED RESEARCH INSTITUTE CALL-ED THE Arab World for Research and Development released the first reliable survey of [...]

BackgroundSexual assault (SA) is a prevalent issue with enduring consequences. Post-SA medical care mainly focuses on injuries, sexually transmitted infection (STI) prevention and detection, as well as preventing unwanted pregnancies. Swift access to post-SA medical care is vital with sexual assault treatment units (SATUs) streamlining this care. The primary aim of our study is to report on post-SA care provided at the national SATU network in Ireland with a secondary aim of analysing factors associated with follow-up attendance for STI testing.MethodsThis is a retrospective cohort study of all acute attendances (<7 days from incident) at the national SATU network between 1 January 2017 to 31 December 2022.ResultsA total of 4159 acute cases presented during the study period. Emergency contraception (EC) was administered to 53.8% (n=1899/3529) of cases, while postexposure prophylaxis (PEP) for chlamydia was given in 75.1% (n=3124/4159) and for HIV in 11.0% (n=304/3387). Hepatitis B vaccination was initiated in 53.7% (n=2233/4159) of cases. 1.4% (n=59/4159) of the attendees were referred to an emergency department for the treatment of injuries. Follow-up appointments were scheduled for 75.8% (3151/4159) of acute cases. 71.6% (n=2257/3151) attended follow-up.Certain factors were found to correlate with a higher likelihood of attending follow-up appointments: adolescents (p<0.0001), concern about drug-facilitated SA (DFSA) (p=0.01), no consumption of recreational drugs before the incident (p<0.0001), alcohol consumption prior to the incident (p=0.01), and not reporting the crime to the police (p<0.001). However, gender (p=0.06) and the presence of injury at time of primary attendance (p=0.97) were not predictive of likelihood of follow-up attendance.ConclusionThis study demonstrates that EC, chlamydia PEP, HIV PEP and hepatitis B vaccination were all administered at SATU. A small proportion of attenders required emergency injury care. Factors influencing attendance at follow-up include age, drug use, alcohol use and police involvement, highlighting the need for tailored patient-centred support.

In every corner of machine learning and statistics, there is a need for estimators that work not just in an idealized model, but even when their assumptions are violated. Unfortunately, in high dimensions, being provably robust and being efficiently computable are often at odds with each other. We give the first efficient algorithm for estimating the parameters of a high-dimensional Gaussian that is able to tolerate a constant fraction of corruptions that is independent of the dimension. Prior to our work, all known estimators either needed time exponential in the dimension to compute or could tolerate only an inverse-polynomial fraction of corruptions. Not only does our algorithm bridge the gap between robustness and algorithms, but also it turns out to be highly practical in a variety of settings. [ABSTRACT FROM AUTHOR]

Pattern recognition receptors (PRRs) of the innate immune system represent the critical front‐line defense against pathogens, and new vaccine formulations target these PRR pathways to boost vaccine responses, through activation of cellular/Th1 immunity. The majority of pediatric vaccines contain aluminum (ALUM) or monophosphoryl lipid A (MPLA) as adjuvants to encourage immune activation. Evidence suggests that elements of the innate immune system, currently being targeted for vaccine adjuvanticity do not fully develop until puberty and it is likely that effective adjuvants for the neonatal and pediatric populations are being overlooked due to modeling of responses in adult systems. We recently reported that the activity of the cytosolic nucleic acid (CNA) sensing family of PRRs is strong in cord blood and peripheral blood of young children. This study investigates the function of CNA sensors in subsets of neonatal innate immune cells and shows that myeloid cells from cord blood can be activated to express T cell costimulatory markers, and also to produce Th1 promoting cytokines. CD80 and CD86 were consistently up‐regulated in response to cytosolic Poly(I:C) stimulation in all cell types examined and CNA activation also induced robust Type I IFN and low levels of TNFα in monocytes, monocyte‐derived macrophages, and monocyte‐derived dendritic cells. We have compared CNA activation to adjuvants currently in use (MPLA or ALUM), either alone or in combination and found that cytosolic Poly(I:C) in combination with MPLA or ALUM can improve expression of activation marker levels above those observed with either adjuvant alone. This may prove particularly promising in the context of improving the efficacy of existing ALUM‐ or MPLA‐containing vaccines, through activation of T cell‐mediated immunity. Cytosolic dsRNA activity in neonatal myeloid cells as a pediatric adjuvant.

A growing body of research is investigating the potential contribution of mitochondrial function to the etiology of type 2 diabetes. Numerous in vitro, in situ, and in vivo methodologies are available to examine various aspects of mitochondrial function, each requiring an understanding of their principles, advantages, and limitations. This review provides investigators with a critical overview of the strengths, limitations and critical experimental parameters to consider when selecting and conducting studies on mitochondrial function. In vitro (isolated mitochondria) and in situ (permeabilized cells/tissue) approaches provide direct access to the mitochondria, allowing for study of mitochondrial bioenergetics and redox function under defined substrate conditions. Several experimental parameters must be tightly controlled, including assay media, temperature, oxygen concentration, and in the case of permeabilized skeletal muscle, the contractile state of the fibers. Recently developed technology now offers the opportunity to measure oxygen consumption in intact cultured cells. Magnetic resonance spectroscopy provides the most direct way of assessing mitochondrial function in vivo with interpretations based on specific modeling approaches. The continuing rapid evolution of these technologies offers new and exciting opportunities for deciphering the potential role of mitochondrial function in the etiology and treatment of diabetes., There has been a dramatic expansion in research investigating the role of mitochondria in the etiology of type 2 diabetes. This trend has been fueled, in part, by recent technological [...]

all those americans here writing about america it's time to give something back, after all our heroes were always the gangster the outlaw why surprised you act like it now, [...]

Self‐assessment of clinical competence is an important tool for effective learning and training for some educational programs. The New York University (NYU) Langone Hospital's Advanced Education in General Dentistry (AEGD) Program has had its residents complete self‐assessment of clinical competency evaluations for many years. The evaluation is used to understand the residents’ perception of their own clinical skill upon beginning the program and to determine the necessary resources to provide to the residents for them to meet program standards. The same evaluation is completed by the residents 6 months later to determine if they perceived advancement in their clinical performance while in the program. Dental education, along with other fields of education was disrupted by the coronavirus disease 2019 (COVID‐19) pandemic. The purpose of this study was to examine the impact of COVID‐19 on clinical competency self‐assessments among the NYU Langone AEGD residents before and during the pandemic. In this cross‐sectional study, data was collected from two AEGD cohorts representing 2019–2020 and 2020–2021 academic years; from July 2019 (n= 196) to January 2020 (n= 189) and July 2020 (n= 202) to January 2021 (n= 184). The self‐assessment evaluations were administered via an online residency management platform on the first days of July and January of the academic year. The survey consisted of 48 questions on “clinical skills and performance” as established by CODA standards for postdoctoral general dentistry programs. Survey response rate was 100% for both cohorts. When comparing results, the findings indicate the COVID‐19 pandemic had interrupted clinical learning during dental school. However, training through the AEGD program led to improvements in perceived clinical competence by the residents in mid‐program evaluation. The self‐assessment evaluation can be used as a tool to enhance training as part of the AEGD program's performance improvement plan.

Sometime in or around 1866 an elderly man, likely dressed in the simple cotton garb of Korea's lower classes, was incarcerated in the royal prison not far from the Kyongbok [...]

The priorities and interests of feminist poets Bernadette Mayer and Lisa Jarnot are discussed. The inspiration for their poetry is explored and the success of the Poetry Project set up by Mayer in New York City is assessed.

Seoul's Gyeongbok Palace begun in 1395 as the royal residence of Korea's Joseon dynasty. The palace is the focus of a 25 billion won restoration project that seeks to restore it to its appearance in 1910 before the palace was almost completely destroyed by the Japanese occupation.

Discusses the debate over the history of the stone stela of Kwanggaet'o, a monarch of the Koguryo Empire, in China. Discovery of the stela; Artifacts discovered in the site; Interpretation of Japanese scholars of passages written on the stela.

Quinone reductase 2 (QR2, E.C. 1.10.5.1) is an enzyme with a feature that has attracted attention for several decades: in standard conditions, instead of recognizing NAD(P)H as an electron donor, it recognizes putative metabolites of NADH, such as N-methyl- and N-ribosyl-dihydronicotinamide. QR2 has been particularly associated with reactive oxygen species and memory, strongly suggesting a link among QR2 (as a possible key element in pro-oxidation), autophagy, and neurodegeneration. In molecular and cellular pharmacology, understanding physiopathological associations can be difficult because of a lack of specific and powerful tools. Here, we present a thorough description of the potent, nanomolar inhibitor [2-(2-methoxy-5H-1,4b,9-triaza(indeno[2,1-a]inden-10-yl)ethyl]-2-furamide (S29434 or NMDPEF; IC50= 5–16 nM) of QR2 at different organizational levels. We provide full detailed syntheses, describe its cocrystallization with and behavior at QR2 on a millisecond timeline, show that it penetrates cell membranes and inhibits QR2-mediated reactive oxygen species (ROS) production within the 100 nM range, and describe its actions in several in vivo models and lack of actions in various ROS-producing systems. The inhibitor is fairly stable in vivo, penetrates cells, specifically inhibits QR2, and shows activities that suggest a key role for this enzyme in different pathologic conditions, including neurodegenerative diseases.

Three-dimensional integrated circuit (3D IC) technology offers a potential breakthrough to enable a paradigm-shift strategy, called “more than Moore,” with novel features and advantages over the conventional 2D process technology. By having three-dimensional interconnections, 3D IC provides substantial wirelength reduction and a massive amount of bandwidth, which gives significant performance improvement to overcome many of the nontrivial challenges in semiconductor industry. Moreover, 3D integration technology enables to stack disparate technologies with various functionalities into a single system-in-package (SiP), introducing “true 3D IC” design.As the first physical design (PD) step, IC floorplanning takes a crucial role to determine IC’s overall design qualities such as footprint area, timing closure, power distribution, thermal management, and so on. However, lack of efficient 3D floorplanning algorithms that practically implement advantages of 3D integration technology is a critical bottleneck for PD automation of 3D IC design and implementation. 3D floorplanning (or packing, block partitioning) is a well-known NP-hard problem, and most of 3D floorplanning algorithms rely on heuristics and iterative improvements. Thus, developing complete and efficient 3D floorplan representations is important, since floorplan representation provides the foundation of data structure to search the solution space for 3D IC floorplanning. A well-defined floorplan representation provides a well-organized and cost-effective methodology to design high-performance 3D IC.We propose a new 3D IC floorplan representation methodology using corner linksand partial order. Given a fixed number of cuboidal blocks and their volume, algorithmic 3D floorplan representations describe topological structure and physical positions/orientations of each block relative to the origin in the 3D floorplan space. In this article, (1) we introduce our novel 3D floorplan representation, called corner links representation, (2) we analyze the equivalence relation between the corner links representation and its corresponding partial order representation, and (3) we discuss several key properties of the corner links representation and partial order representation. The corner links representation provides a complete and efficient structure to assemble the original 3D mosaic floorplan. Also, the corner links representation for the non-degenerate 3D mosaic floorplan can be equivalently expressed by the four trees representation. The partial order representation defines the topological structure of the 3D floorplan with three transitive closure graphs (TCG) for each direction and captures all stitching planes in the 3D floorplan in the order of their respective directions. We demonstrate that the corner links representation can be reduced to its corresponding partial order representation, indicating that the corner links representation shares well-defined and -studied features/properties of 3D TCG-based floorplan representation. If the partial order representation describes relations between any pairs of blocks in the 3D floorplan, then the floorplan is a valid floorplan. We show that the partial order representation can restore the absolute coordinates of all blocks in the 3D mosaic floorplan by using the given physical dimensions of blocks.

Jesuit Cartography in China In 1661 a young boy of seven donned the imperial yellow robes, took up residence in the vermilion palace of the Chinese emperors, and, invested with [...]

Autotaxin (ATX) is an adipokine that generates the bioactive lipid, lysophosphatidic acid (LPA). ATX-LPA signaling has been implicated in diet-induced obesity and systemic insulin resistance. However, it remains unclear whether the ATX-LPA pathway influences insulin function and energy metabolism in target tissues, particularly skeletal muscle, the major site of insulin-stimulated glucose disposal. The objective of this study was to test whether the ATX-LPA pathway impacts tissue insulin signaling and mitochondrial metabolism in skeletal muscle during obesity. Male mice with heterozygous ATX deficiency (ATX+/−) were protected from obesity, systemic insulin resistance, and cardiomyocyte dysfunction following high-fat high-sucrose (HFHS) feeding. HFHS-fed ATX+/−mice also had improved insulin-stimulated AKT phosphorylation in white adipose tissue, liver, heart, and skeletal muscle. Preserved insulin-stimulated glucose transport in muscle from HFHS-fed ATX+/−mice was associated with improved mitochondrial pyruvate oxidation in the absence of changes in fat oxidation and ectopic lipid accumulation. Similarly, incubation with LPA decreased insulin-stimulated AKT phosphorylation and mitochondrial energy metabolism in C2C12 myotubes at baseline and following palmitate-induced insulin resistance. Taken together, our results suggest that the ATX-LPA pathway contributes to obesity-induced insulin resistance in metabolically relevant tissues. Our data also suggest that LPA directly impairs skeletal muscle insulin signaling and mitochondrial function.

Spectral and coherence evolutions were measured for supercontinuum (SC) generated in a 2.7 cm highly nonlinear tellurite photonic crystal fiber. Numerical simulations were performed based on the generalized nonlinear Schrödinger equation with noise. The measurements show that coherence degradation first occurs after soliton fission, and then spreads to longer wavelengths as the average power of the SC increases. The solitonic coherence shows much slower degradation than the overall coherence.

Autotaxin (ATX) is an adipokine that generates the bioactive lipid, lysophosphatidic acid. Despite recent studies implicating adipose-derived ATX in metabolic disorders including obesity and insulin resistance, the nutritional and hormonal regulation of ATX in adipocytes remains unclear. The current study examined the regulation of ATX in adipocytes by glucose and insulin and the role of ATX in adipocyte metabolism. Induction of insulin resistance in adipocytes with high glucose and insulin concentrations increased ATX secretion, whereas coincubation with the insulin sensitizer, rosiglitazone, prevented this response. Moreover, glucose independently increased ATX messenger RNA (mRNA), protein, and activity in a time- and concentration-dependent manner. Glucose also acutely upregulated secreted ATX activity in subcutaneous adipose tissue explants. Insulin elicited a biphasic response. Acute insulin stimulation increased ATX activity in a PI3Kinase-dependent and mTORC1-independent manner, whereas chronic insulin stimulation decreased ATX mRNA, protein, and activity. To examine the metabolic role of ATX in 3T3-L1 adipocytes, we incubated cells with the ATX inhibitor, PF-8380, for 24 hours. Whereas ATX inhibition increased the expression of peroxisome proliferator-activated receptor-γ and its downstream targets, insulin signaling and mitochondrial respiration were unaffected. However, ATX inhibition enhanced mitochondrial H2O2 production. Taken together, this study suggests that ATX secretion from adipocytes is differentially regulated by glucose and insulin. This study also suggests that inhibition of autocrine/paracrine ATX-lysophosphatidic acid signaling does not influence insulin signaling or mitochondrial respiration, but increases reactive oxygen species production in adipocytes.

Costs associated with work-related back disability have been increasing. Worker's Compensation claims in Tennessee, finalized during 1986, were studied. There were 29,421 claims costing $160 million. Medical expenses generated 40 percent of the total cost of claims, with the remainder attributed to lost work time. Claim analysis revealed 27 percent involved back injuries, and 90 percent of these showed no objective evidence of muscle or bone impairment and were classified as nonspecific. These nonspecific back injuries accounted for 40 percent of the total cost of Worker's Compensation claims. The median interval for return to work was 31 days, but the average for the group was 72 days, indicating a highly skewed distribution. The 10 percent with the highest claim cost accounted for 57 percent of the total expenditure for Worker's Compensation claims. This study, along with other studies cited by the author, suggests that the current system of back-injury assessment and treatment contributes to the very high costs of nonspecific back-injury. There is a marked contrast between relatively low costs when a person returns to work soon after the injury, and very high costs for those who do not return for 90 days or more. The financial data presented here support the need for a reappraisal of the clinical management of nonspecific low-back pain. It has been suggested that the patient be given more responsibility for his progress, that medical management be focused more on rehabilitation than on rest, and that an early return to work is both desirable and appropriate.

Ultrafast X-ray spectroscopies require flexible X-ray properties together with high temporal and spectral resolution. Here, we demonstrate simultaneous sub-20 fs and sub-eV resolutions for pump/probe experiments, without the need for additional photon arrival-time monitors.

Soil functional zone management (SFZM) is a novel strategy for row crop management. Especially when used with cover cropping, SFZM may play an important role in enhancing agricultural production and sustainability via beneficial effects on soil nitrogen cycling. Field studies in four states across the U.S. showed that SFZM can enhance control of nitrogen cycling, increasing nitrogen availability near crop roots in synchrony with corn peak nitrogen demand. Earn 0.5 CEUs in Soil & Water Management by reading this article and taking the quiz at www.certifiedcropadviser.org/certifications/self‐study/800.

Ridge tillage (RT) can promote increases in soil C and aggregation at greater rates than conventional tillage, but few studies have investigated how RT may affect soil N distributions across the row/inter‐row space. Using a spatially intensive sampling design, we monitored soil potentially mineralizable N (PMN), inorganic N, and plant tissue N in a field study comparing RT and chisel plow (CP) systems. Experiments were fully replicated at two sites in Urbana, IL and Mason, MI during the 2012 growing season. At both sites, a strong interaction effect of tillage × row position was observed for PMN (Illinois, p= 0.005; Michigan, p =0.02) with higher levels of PMN in the in‐row (IR) position than off‐row (OR) and between‐row (BR) positions of RT treatments following re‐ridging. Plant tissue analyses indicated a significant RT advantage at both sites (Illinois, p =0.04; Michigan, p =0.02), and a structural equation modeling (SEM) analysis indicated that PMN at the 0‐ to 5‐cm depth in the IR position following re‐ridging had a significant effect on inorganic N at the same position and, in turn, a strong influence on plant tissue N (comparative fit index = 0.86, standardized root mean square residual = 0.11, Akaike wt. = 1). Overall, our results suggest that RT can establish soil functional zones (SFZ) with distinct N profiles and that the relocation of PMN in‐row may increase the spatial efficiency of N provisioning relative to conventional tillage.

In studying the enumerative theory of super characters of the group of upper triangular matrices over a finite field, we found that the moments (mean, variance, and higher moments) of novel statistics on set partitions of [n]={1,2,⋯,n} have simple closed expressions as linear combinations of shifted bell numbers. It is shown here that families of other statistics have similar moments. The coefficients in the linear combinations are polynomials in n. This allows exact enumeration of the moments for small nto determine exact formulae for all n.

We prove new bounds on the average sensitivity of the indicator function of an intersection of khalfspaces. In particular, we prove the optimal bound of Onlog(k) $O\left (\sqrt {n\log (k)}\right)$ . This generalizes a result of Nazarov, who proved the analogous result in the Gaussian case, and improves upon a result of Harsha, Klivans and Meka. Furthermore, our result has implications for the runtime required to learn intersections of halfspaces. Primary; 52C45

Increasingly, funding agencies are investing in integrated and transdisciplinary research to tackle “grand challenge” priority areas, critical for sustaining agriculture and protecting the environment. Coordinating multidisciplinary research teams capable of addressing these priority areas, however, presents its own unique set of challenges, ranging from bridging across multiple disciplinary perspectives to achieve common questions and methods to facilitating engagement in holistic and integrative thinking that promotes linkages from scholarship to societal needs. We propose that structural equation modeling (SEM) can provide a powerful framework for synergizing multidisciplinary research teams around grand challenge issues. Structural equation modeling can integrate both visual and statistical expression of complex hypotheses at all stages of the research process, from planning to analysis. Three elements of the SEM framework are particularly beneficial to multidisciplinary research teams; these include (i) a common graphical language that transcends disciplinary boundaries, (ii) iterative, critical evaluation of complex hypotheses involving manifest and latent variables and direct and indirect interactions, and (iii) enhanced opportunities to discover unanticipated interactions or causal pathways as empirical data are tested statistically against the model. Using our ongoing multidisciplinary, multisite field investigation of climate change adaptation and mitigation in annual row crop agroecosystems as a case study, we demonstrate the value of the SEM framework for project design, coordination, and implementation and provide recommendations for its broader application as a means to more effectively engage and address issues of critical societal concern.

Mitochondrial ion transport systems play a central role in cell physiology. Rates of Ca2+and K+transport across the inner mitochondrial membrane have been derived from the measurement of ion accumulation over time within functional isolated mitochondria or mitochondria of cultured cells. Alternatively, the electrical currents generated by ionic flux have been directly measured in purified and swollen mitochondrial samples (mitoplasts) or reconstituted channels, and typically range from 1 pA to several 100s pA. However, the direct electrophysiological approach necessarily requires extensive processing of the mitochondria prior to measurement, which can only be performed on isolated mitoplasts. To compare rates of mitochondrial ion transport measured in electrophysiological experiments to those measured in intact mitochondria and cells, we converted published rates of mitochondrial ion uptake into units of ionic current. We estimate that for monovalent ions, uptake by intact mitochondria at the rate of 1 nmol ∙ mg−1protein ∙ min−1is equivalent to 0.2 fA of current per whole single mitochondrion (0.4 fA for divalent ions). In intact mitochondria, estimated rates of electrogenic cation uptake are limited to 1–100 fA of integral current per single mitochondrion. These estimates are orders of magnitude lower than the currents through mitochondrial channels directly measured via patch-clamp or artificial lipid bilayer approaches.

Over the past two decades, a large collection of transposable elements inserted at various locations in the Drosophila melanogaster genome has been assembled. These transposons are frequently utilized in imprecise excision screens to generate deletions in genes of interest. In general, these screens involve genetic manipulations to combine a non-autonomous transposon and the appropriate transposase in individual male or female flies. DNA double-strand breaks are created via transposase action in both somatic and germline cells of these individuals and inaccurate repair events are recovered in the progeny. Because deletion-prone repair of transposon-induced double-strand breaks is rare, these screens generally require a significant investment of time and resources. We recently reported that conducting imprecise excision screens in mus309 mutant flies, which lack the Drosophila ortholog of the Bloom Syndrome helicase, results in an increase in both the number and size of deletions recovered. Here, we provide additional information for Drosophila researchers wishing to utilize this technique. In addition, we discuss how the general principle behind this technique can be applied in other contexts where double-strand breaks are being generated for the purpose of genome modification.

Frequency-resolved optical gating (FROG) is a technique used to measure ultrafast laser pulses by optically producing a spectrogram, or FROG trace, of the measured pulse. While a great deal of information about the pulse can be gleaned from its FROG trace, quantitative pulse information must be obtained using an iterative two-dimensional phase retrieval algorithm. A general spectrogram/sonogram inversion algorithm called principal components generalized projections (PCGP) that can be applied to pulse measurement schemes, such as FROG, is reviewed. The algorithm is fast, robust, and can invert FROG traces in real time, making commercial pulse measurement systems based on FROG a reality. Measurement rates are no longer algorithm limited; they are data-acquisition limited. Also, because of some of its unique properties, the PCGP algorithm has found applications in measuring attosecond pulses and measuring telecommunications pulses. In addition, the PCGP structures the inversion and measurement process in a way that can allow new insights into convergence properties of spectrogram and sonogram inversion algorithms.

Complex-conjugate-resolved Fourier-domain optical coherence tomography, where the quadrature components of the interferogram are obtained by simultaneous acquisition of the first and second harmonics of the phase-modulated interferogram, is applied to multisurface test targets and biological samples. The method provides efficient suppression of the complex-conjugate, dc, and autocorrelation artifacts. A complex-conjugate rejection ratio as high as 70 dB is achieved.

This article reflects on the film "Fireworks" by Kenneth Anger and the poem "The Torso" by Robert Duncan. The author comments that the film is the extension of the basic themes of the poem. The author also suggests to focus on the film first before analyzing the poem, where homosexuality is depicted on both literatures.

The article presents an algorithm on finding the best grade to drop in the students quizzes. A natural criterion to decide which grades to drop would be to drop the set of grades that maximizes the student's final grade. The goal is to distinguish the deletion set which will result in the student receiving the highest possible final grade, the optimal deletion set.

Let Sa,b= {an+b:n≥ 0 } where nis an integer. Let Pa,b(n) denote the number of partitions of ninto elements of Sa,b. In particular, we have the generating function, $$ \sum_{n=0}^{\infty} P_{a,b}(n)q^{n}=\prod_{n=0}^{\infty} \frac{1}{(1-q^{an+b})}. $$Let Sa,b= {an+b:n≥ 0 } where nis an integer. Let Pa,b(n) denote the number of partitions of ninto elements of Sa,b. In particular, we have the generating function, $$ \sum_{n=0}^{\infty} P_{a,b}(n)q^{n}=\prod_{n=0}^{\infty} \frac{1}{(1-q^{an+b})}. $$

A Michelson-type spectral interferometer that uses a common beam path for the reference and the sample arms is described. This optical arrangement is more compact and stable than the more commonly used dual-arm interferometer and is well suited for frequency-domain optical coherence tomography of biological samples. With a 16-bit CCD camera, the instrument has sufficient dynamic range and resolution for imaging to depths of 2 mm in scattering biological materials. Images obtained with this spectral interferometer are presented, including cross-sectional images in a Xenopus laevis tadpole.

Frequency-resolved optical gating (FROG) is a technique used to measure the intensity and phase of ultrashort laser pulses through the optical construction of a spectrogram of the pulse. To obtain quantitative information about the pulse from its spectrogram, an iterative two-dimensional phase-retrieval algorithm must be used. Current algorithms are quite robust, but retrieval of all the pulse information can be slow. Previous real-time FROG trace inversion work focused on second-harmonic-generation FROG, which has an ambiguity in the direction of time, and required digital signal processors (DSPs). We develop a simplified real-time FROG device based on a single-shot geometry that no longer requires DSPs. We use it and apply the principal component generalized projections algorithm to invert polarization gate FROG traces at rates as high as 20 Hz.

Abstract:In February 1866 anti-Christian persecutions by the Taewǒn'gun resulted in the execution of nine French Jesuit missionaries secretly proselytizing in Korea. French reaction was extreme, with the French Far Eastern Squadron undertaking a small-scale invasion that fall. The attack, made in hopes of inflicting retribution and gaining concessions, was a dismal failure, ending in French withdrawal and the end of French missionary activity in Korea for a decade. The decision to attack has usually been viewed solely in its "Korean context" and thus been interpreted as a rash reaction to events there by the leading French diplomat in China. When viewed in the broader context of French policy in the Far East, especially China, the French decision to attack can be better understood.

We recently introduced a new technique, frequency-resolved optical gating (FROG), for directly determining the full intensity I(t) and phase φ(t) of a single femtosecond pulse. By using almost any instantaneous nonlinear-optical interaction of two replicas of the ultrashort pulse to be measured, FROG involves measuring the spectrum of the signal pulse as a function of the delay between the replicas. The resulting trace of intensity versus frequency and delay yields an intuitive display of the pulse that is similar to the pulse spectrogram, except that the gate is a function of the pulse to be measured. The problem of inverting the FROG trace to obtain the pulse intensity and phase can also be considered a complex two-dimensional phase-retrieval problem. As a result, the FROG trace yields, in principle, an essentially unique pulse intensity and phase. We show that this is also the case in practice. We present an iterative-Fourier-transform algorithm for inverting the FROG trace. The algorithm is unusual in its use of a novel constraint: the mathematical form of the signal field. Without the use of a support constraint, the algorithm performs quite well in practice, even for pulses with serious phase distortions and for experimental data with noise, although it occasionally stagnates when pulses with large intensity fluctuations are used.

We recently introduced frequency-resolved optical gating (FROG), a technique for measuring the intensity and phase of an individual, arbitrary, ultrashort laser pulse. FROG can use almost any instantaneous optical nonlinearity, with the most common geometries being polarization gate, self-diffraction, and second-harmonic generation. The experimentally generated FROG trace is intuitive, visually appealing, and can yield quantitative information about the pulse parameters (such as temporal and spectral width and chirp). However, the qualitative and the quantitative features of the FROG trace depend strongly on the geometry used. We compare the FROG traces for several common ultrashort pulses for these three common geometries and, where possible, develop scaling rules that allow one to obtain quantitative information about the pulse directly from the experimental FROG trace. We illuminate the important features of the various FROG traces for transform-limited, linearly chirped, self-phase modulated, and nonlinearly chirped pulses, pulses with simultaneous linear chirp and self-phase modulation, and pulses with simultaneous linear chirp and cubic phase distortion, as well as double pulses, pulses with phase jumps, and pulses with complex intensity and phase substructure.

Absolute concentrations of water vapor are measured in microgravity (μ-g), nonpremixed methane, and propane jet flames with diode-laser wavelength modulation spectroscopy. These experiments are performed in the 2.2-s μ-g drop facility at the NASA Lewis Research Center. Abel inversion methods are used to determine time-dependent radial profiles from eight line-of-sight projections across the flames. At all measured heights above the nozzle, water vapor spatial distributions in μ-g flames are much wider than their 1-g counterparts. Radial growth of the water signal continues throughout the drop, verifying earlier suggestions that a steady state is not reached during the duration of the test, despite a quasi-steady flame shape. Large amounts of water vapor are observed at larger radii, at odds with visual (video) observations and numerical predictions.