Rapid computational routines are presented for calculating x2 from frequency data in the following cases: (1) test of goodness of fit between an observed and a theoretical distribution; (2) test of independence of distributions displayed in an r ✗ c table; (3) test of independence of distributions displayed in an r ✗ 2 table. A rapid method of computing the contingency coefficient also follows from the procedure used in the second of these cases.

It is proposed that a satisfactory criterion for an approximation to simple structure is the minimization of the sums of cross-products (across factors) of squares of factor loadings. This criterion is completely analytical and yields a unique solution; it requires no plotting, nor any decisions as to the clustering of variables into subgroups. The equations involved appear to be capable only of iterative solution; for more than three or four factors the computations become extremely laborious but may be feasible for high-speed electronic equipment. Either orthogonal or oblique solutions may be achieved. For illustrations, the Johnson-Reynolds study of “flow” and “selection” factors and the Thurstone box problem are reanalyzed. The presence of factorially complex tests produces a type of hyperplanar fit which the investigator may desire to adjust by graphical rotations; the smaller the number of such tests, the closer the criterion comes to approximating simple structure.

A study is made of the extent to which correlations between items and between tests are affected by the difficulties of the items involved and by chance success through guessing. The Pearsonian product-moment coefficient does not necessarily give a correct indication of the relation between items or sets of items, since it tends to decrease as the items or tests become less similar in difficulty. It is suggested that the tetrachoric correlation coefficient can properly be used for estimating the correlation between the continua underlying items or sets of items even though they differ in difficulty, and a method for correcting a 2 × 2 table for the effect of chance is proposed.

A multiple-factor analysis was made of a battery of 42 tests of verbal abilities administered to 119 college adults. Where necessary, the distributions of test scores were normalized before the inter-test correlations were computed. Thurstone's M (Memory or Rote Learning) factor has been confirmed, but his V (Verbal Relations) factor seems to have been split into two or possibly three factors, C, J, and G; and his W (Word Fluency) factor has been split into two factors, A and E. The C factor seems to represent the richness of the individual's stock of linguistic responses, and the J factor seems to involve the ability to handle semantic relationships. No satisfactory interpretation can as yet be made of the G factor. The A factor seems to correspond to the speed of association for common words where there is a high degree of restriction as to appropriate responses. The E factor is described as an associational facility with verbal material where the only restriction is that the responses must be syntactically coherent. The new factors are: F, facility and fluency in oral speech; H, facility in attaching appropriate names or symbols to stimuli; and D, speed of articulatory movements.

Very general multilinear models, called CANDELINC, and a practical least-squares fitting procedure, also called CANDELINC, are described for data consisting of a many-way array. The models incorporate the possibility of general linear constraints, which turn out to have substantial practical value in some applications, by permitting better prediction and understanding. Description of the model, and proof of a theorem which greatly simplifies the least-squares fitting process, is given first for the case involving two-way data and a bilinear model. Model and proof are then extended to the case of N-way data and an N-linear model for general N. The case N = 3 covers many significant applications. Two applications are described: one of two-way CANDELINC, and the other of CANDELINC used as a constrained version of INDSCAL. Possible additional applications are discussed.

OBJECTIVES/GOALS: Fluid boluses are administered to hypotensive, critically ill children but may not reverse hypotension, leading to delay of vasoactive infusion, end-organ damage, and mortality. We hypothesize that a machine learning-based model will predict which children will have sustained response to fluid bolus. METHODS/STUDY POPULATION: We will conduct a single-center retrospective observational cohort study of hypotensive critically ill children who received intravenous isotonic fluid of at least 10 ml/kg within 72 hours of pediatric intensive care unit admission between 2013 and 2023. We will extract physiologic variables from stored bedside monitors data and clinical variables from the EHR. Fluid responsive (FR) will be defined as a MAP increase by 310%. We will construct elastic net, random forest, and a long short-term memory models to predict FR. We will compare complicated course (multiple organ dysfunction on day 7 or death by day 28) between: 1) FRs and non-FRs, 2) predicted FRs and non-FRs, 3), FRs and non-FRs stratified by race/ethnicity, and 4) FRs and non-FRs stratified by sex as a biologic variable. RESULTS/ANTICIPATED RESULTS: We anticipate approximately 800 critically ill children will receive 2,000 intravenous isotonic fluid boluses, with a 60% rate of FR. We anticipate being able to complete all three models. We hypothesize that the model with the best performance will be the long short-term memory model and the easiest to interpret will be the tree-based random forest model. We hypothesize non-FRs will have a higher complicated course than FRs and that predicted non-FRs will have a higher rate of complicated course than FRs. Based on previous adult studies, we hypothesize that there will be a higher rate of complicated course in patients of black race and/or Hispanic ethnicity when compared to non-Hispanic white patients. We also hypothesize that there will be no difference in complicated course when comparing sex as a biologic variable. DISCUSSION/SIGNIFICANCE: We have a critical need for easily-deployed, real-time prediction of fluid response to personalize and improve resuscitation for children in shock. We anticipate the clinical application of such a model will decrease time with hypotension for critically ill children, leading to decreased morbidity and mortality.

Recurrent outbreaks of haemolytic uraemic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli (STEC) serotype O55:H7 occurred in England between 2014 and 2018. We reviewed the epidemiological evidence to identify potential source(s) and transmission routes of the pathogen, and to assess the on-going risk to public health. Over the 5-year period, there were 43 confirmed and three probable cases of STEC O55:H7. The median age of cases was 4 years old (range 6 months to 69 years old) and over half of all cases were female (28/46, 61%). There were 36/46 (78.3%) symptomatic cases, and over half of all cases developed HUS (25/46, 54%), including two fatal cases. No common food or environmental exposures were identified, although the majority of cases lived in rural or semi-rural environments and reported contact with both wild and domestic animals. This investigation informed policy on the clinical and public health management of HUS caused by STEC other than serotype O157:H7 (non-O157 STEC) in England, including comprehensive testing of all household contacts and household pets and more widespread use of polymerase chain reaction assays for the rapid diagnosis of STEC-HUS.

We report the first case of valacyclovir-induced psychosis with symptoms of mania in an adolescent female with no psychiatric history. the patient presented with irritable mood, decreased need for sleep, auditory hallucinations, and grandiose delusions 72 hours after starting oral valacyclovir for newly acquired genital herpes. She was on no other medications. Delirium was ruled out by history and physical, urine toxicology was negative, head CAT scan was unremarkable, as were thyroid hormones and basic laboratories. the symptoms continued after stopping the valacyclovir, but improved with risperidone. after withdrawal of risperidone, the patient has been symptom free for 4 months. According to the Naranjo Adverse Drug Reaction (ADR) probability scale, this case report scores as a possible drug reaction. Although there are no reports of neuropsychiatric side effects with valacyclovir, there are for the medications structural analogs, acyclovir and ganciclovir. These cases were primarily in elderly patients who are immunocompromised, have renal dysfunction and receive the medication by the intravenous route. other anti-viral medications, such as interferon, have also been shown to induce mood symptoms, including depression and mania. Genital Herpes is a common and painful infection, with no known cure. Three medications, acyclovir, valacyclovir and famciclovir, have been shown to reduce the duration and severity of the disease. Clinicians should be aware that Valacyclovir and its analogs may induce psychosis with manic symptoms in young, healthy patients with no previous psychiatric history. Further research is needed to demonstrate a clear association, causal relationship and possible mechanism for the reaction.

A developing application of laser-driven currents is the generation of magnetic fields of picosecond–nanosecond duration with magnitudes exceeding $B=10~\text{T}$. Single-loop and helical coil targets can direct laser-driven discharge currents along wires to generate spatially uniform, quasi-static magnetic fields on the millimetre scale. Here, we present proton deflectometry across two axes of a single-loop coil ranging from 1 to 2 mm in diameter. Comparison with proton tracking simulations shows that measured magnetic fields are the result of kiloampere currents in the coil and electric charges distributed around the coil target. Using this dual-axis platform for proton deflectometry, robust measurements can be made of the evolution of magnetic fields in a capacitor coil target.

Environmental information from place-names has largely been overlooked by geoarchaeologists and fluvial geomorphologists in analyses of the depositional histories of rivers and floodplains. Here, new flood chronologies for the rivers Teme, Severn, and Wye are presented, modelled from stable river sections excavated at Broadwas, Buildwas, and Rotherwas. These are connected by the Old English term *wæsse, interpreted as ‘land by a meandering river which floods and drains quickly’. The results reveal that, in all three places, flooding during the early medieval period occurred more frequently between AD 350–700 than between AD 700–1100, but that over time each river's flooding regime became more complex including high magnitude single events. In the sampled locations, the fluvial dynamics of localized flood events had much in common, and almost certainly differed in nature from other sections of their rivers, refining our understanding of the precise nature of flooding which their names sought to communicate. This study shows how the toponymic record can be helpful in the long-term reconstruction of historic river activity and for our understanding of past human perceptions of riverine environments.

Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.

We have performed experiments to determine the extents to which Fe and H2O are lost from hydrous basaltic melts contained in Au80Pd20 and graphite-lined Pt capsules at 0.7 –1 GPa and 1300–1350°C. All experiments were performed in the piston-cylinder apparatus. In order to minimize the possibility of rupture of the AuPd capsule and to control H2O loss we used a double-capsule method. The inner welded 2 mm diameter Au80Pd20 capsule was placed inside a welded 3 mm diameter Pt capsule, the intervening space being packed with hydrous sample. Loss of FeO* from the sample was found to be ≤4% relative in both the Au80Pd20 and graphite-lined Pt capsules in experiments of up to 24 h duration. Loss of H2O is greater and it depends on the oxidation state of the starting materials and the nature of the capsule. For starting mixes fired at 1 log fO2 unit above the quartz-fayalite-magnetite (QFM) buffer at 1 atm, H2O loss from Au80Pd20 capsules averaged 9% relative. Starting mixes fired at 1 log fO2 unit below the QFM buffer at 1atm lost, on average, 32% of their H2O when run in Au80Pd20 capsules at high pressure. All samples run in graphite-lined Pt capsules experienced dramatic H2O loss, averaging 52% relative, irrespective of initial oxidation state. We conclude that Au80Pd20 capsules are suitable for high-pressure hydrous melting experiments and that the sample loses very little Fe. In order to minimize H2O-loss, however, it is important that the starting materials be relatively oxidized.

Lactobacillus acidophilus fermentation products have been used to improve the performance of nursery pigs. However, research on the influence of this supplement on health is lacking. This study was designed to determine if feeding a Lactobacillus acidophilus fermentation product to weaned pigs would reduce stress and acute phase responses (APR) following a lipopolysaccharide (LPS) challenge. Pigs (n=30; 6.4±0.1 kg) were individually housed in stainless steel pens with ad libitum access to feed and water. Pigs were weighed upon arrival, assigned to one of three groups (n=10/treatment), and fed for 18 days: (1) Control, fed a non-medicated starter diet; (2) Control diet with the inclusion of a Lactobacillus acidophilus fermentation product at 1 kg/metric ton (SGX1) and (3) Control diet with the inclusion of a Lactobacillus acidophilus fermentation product at 2 kg/metric ton (SGX2). On day 7 pigs were anesthetized for insertion of an i.p. temperature device, and similarly on day 14 for insertion of a jugular catheter. Pigs were challenged i.v. with LPS (25 µg/kg BW) on day 15. Blood samples were collected at 0.5 h (serum) and 1 h (complete blood cell counts) intervals from −2 to 8 h and at 24 h relative to LPS administration at 0 h. Pigs and feeders were weighed on days 7, 14 and 18. The supplemented pigs had increased BW and average daily gain before the challenge. In response to LPS, there was a greater increase in i.p. temperature in Control pigs compared with supplemented pigs. In addition, cortisol was reduced in SGX2 pigs while cortisol was elevated in SGX1 pigs at several time points post-challenge. White blood cells, neutrophils and lymphocytes were decreased in SGX1 and SGX2 compared with Control pigs. Furthermore, the pro-inflammatory cytokine response varied by treatment and dose of treatment. Specifically, serum TNF-α was greatest in SGX2, intermediate in Control, and least in SGX1 pigs, while the magnitude and temporal pattern of IFN-γ in SGX2 pigs was delayed and reduced. In contrast, IL-6 concentrations were reduced in both SGX treatment groups compared with Control pigs. These data demonstrate that different supplementation feed inclusion rates produced differential responses, and that feeding SynGenX to weaned pigs attenuated the APR to an LPS challenge.