Midpoint In Time Research Articles

Multiple Video Frame Interpolation via Enhanced Deformable Separable Convolution.

Generating non-existing frames from a consecutive video sequence has been an interesting and challenging problem in the video processing field. Typical kernel-based interpolation methods predict pixels with a single convolution process that convolves source frames with spatially adaptive local kernels, which circumvents the time-consuming, explicit motion estimation in the form of optical flow. However, when scene motion is larger than the pre-defined kernel size, these methods are prone to yield less plausible results. In addition, they cannot directly generate a frame at an arbitrary temporal position because the learned kernels are tied to the midpoint in time between the input frames. In this paper, we try to solve these problems and propose a novel non-flow kernel-based approach that we refer to as enhanced deformable separable convolution (EDSC) to estimate not only adaptive kernels, but also offsets, masks and biases to make the network obtain information from non-local neighborhood. During the learning process, different intermediate time step can be involved as a control variable by means of an extension of coord-conv trick, allowing the estimated components to vary with different input temporal information. This makes our method capable to produce multiple in-between frames. Furthermore, we investigate the relationships between our method and other typical kernel- and flow-based methods. Experimental results show that our method performs favorably against the state-of-the-art methods across a broad range of datasets. Code will be publicly available on URL: https://github.com/Xianhang/EDSC-pytorch.

History Matching of Petroleum Engineering Graduation Rates

An email discussion among the four members focused on one of several charts created by Tom Blasingame, 2021 SPE president. A summary of their insights follows. Tom Blasingame explained the chart, which led to further discussion. The “reference” trend shown (red) occurs over the period from 1970 to 2000, which peaked at 1,587 BS graduates around 1984. It is a Gaussian probability distribution fitted to the data provided by Lloyd Heinze, professor at Texas Tech University’s Bob L. Herd Department of Petroleum (solid black line), and data extracted from a 1991 paper by John C. Calhoun, who was then at Texas A&M University and previously served as the 1964 SPE president. The reference trend is then shifted in time to the period from 2003 to 2033 (green). The mean and standard deviation of the statistical trends are the same; only the midpoint in time and peak in BS graduates are adjusted for each period. We note an excellent match of the data in the period from 2003 to 2033. Taking the reference trend back in time to the period from 1940 to 1970 (purple trend), we do not get a reasonable match of the data, with the exception of a slump from about 1951 to 1956. It is difficult to explain this feature, other than to note that in this timeframe the US began to import significant quantities of oil. Regardless, we note the statistical trend does capture the beginning and end of this distribution, and we recognize that there is no single peak in the data trend from 1940 to 1970. If we follow the historical trends and the current increase in oil prices and consider the need for oil and gas in the foreseeable future, we predict that the downward trend may stabilize as it did before and level out at the range of 250 graduates a year, while the demand for graduates is much higher. In this scenario, I consider the following positives and negatives. - Negative publicity around fossil fuels and social/political pressure to shut down the oil industry will continue, pulling the graduates’ figures down. - Current energy shortages and price spikes will remind the public that the end of oil and gas is not near, which will start to improve the image of petroleum engineering. - Deepening global economic crises and rising inflation will reduce people’s buying power and move them from highly idealistic to mostly pragmatic decisions. That, combined with the unmatched salary prospect of petroleum engineers with only a 4-year undergraduate degree, will increase the interest in the PE degree. - Considering that oil and gas will remain to be slightly over 50% of the energy mix, and that the energy demand will increase by 47% by 2050, we will need to produce roughly 45% more oil and gas than today. Even with the increased efficiency … we will need more petroleum engineers.

Considering EU External Relations after Brexit: Introduction

This special issue of Europe and the World: A law review consists of selected articles that were presented at a workshop on External Relations in the post-Brexit EU, University of Strathclyde, Glasgow in October 2018. The workshop was generously funded by the James Madison Charitable Trust and the New Professors Fund of the University of Strathclyde. The purpose of the workshop was to consider the multifaceted dimensions of Brexit on the European Union’s external relations, and in particular to consider how interdisciplinary perspectives can enrich our understanding of the law underpinning the subject. This includes the EU’s externally facing institutional frameworks; law and policy on foreign, security and defence policies; trade and the Common Commercial Policy; and bilateral agreements with third countries or regions. The workshop was held around the mid-point in time from the referendum of June 2016 until the eventual departure of the UK on 31 January 2020 (although the final departure date and exit arrangements were unknown at the time). As such, the workshop contributors based their analyses on what the future impact of Brexit might be. Drawing on the extensive scholarship on EU external relations that has blossomed over previous decades, the authors of this special issue have been able to comprehensively analyse what future EU external relations might look like.

HIV avidity index performance using a modified fourth-generation immunoassay to detect recent HIV infections.

Detecting recent HIV infections is important to evaluate incidence and monitor epidemic trends. We aimed to evaluate the diagnostic performance and accuracy of the avidity index (AI) for discriminating for recent HIV infections. We collected serum samples from HIV-1 positive individuals: A) with known date of infection (midpoint in time between last HIV-negative and first HIV-positive test); B) infected for >1 year. Samples were divided into two aliquots: one diluted with phosphate buffered saline (PBS) and the other with 1 M guanidine. Both aliquots were assayed by the Architect HIV Ag/Ab Combo 4th generation assay (Abbott). We compared AI found in recent (RI=<6 months from seroconversion) and established (EI) infections. The diagnostic accuracy was evaluated by receiver operating characteristic (ROC) curve analysis. The proportion of samples misclassified as recent (FRR) was calculated. In total, 647 samples were collected: 455 in group A (51.6% RI and 48.4% EI) and 192 in group B. Among these, sixteen samples were from elite controllers, 294 from treated patients, 328 from patients infected with non-B subtypes. Samples before antiretroviral initiation showed a mean AI significantly lower among RI compared to EI (0.66+0.28 vs. 1.00±0.12; p<0.000). The FRR was 0% using a cut-off of ≤0.70. An extremely low FRR was observed among elite controllers, samples with low VL or CD4. HIV subtype had no impact on AI misclassifications. All individuals in group A reached the AI threshold of 0.80 within 24 months after seroconversion. The AI is an accurate serological marker for discriminating recent from established HIV infections and meets WHO requirements for HIV incidence assays.

Cardiovascular activity and chronic pain severity

ObjectiveObjective markers of chronic pain severity are needed when examining and treating patients with chronic pain whose suffering may be overstated or underestimated. This study tested a hypothesis that the strength of cardiovascular (CV) reactivity in response to a social evaluative threat and orthostatic challenge is a reliable index of severity of pain-related complaints. MethodsMeasurement of CV reactivity and response styles in 34 men and 16 women with chronic pain from different bodily injuries, were retrieved from a larger database of patients. Measurement of CV reactivity in response to a postural challenge was repeated twice (sessions 1 and 2) on the same day of a medical examination which includes a psychosocial evaluation. ResultsA decrease in systolic blood pressure (SBP) from session 1 to session 2 was found in subjects with low pain severity scores, but not in those with high pain severity scores. High scores for pain catastrophizing/magnification and pain-related emotional distress were independently associated respectively with a SBP increase at an early-point in time and a SBP decrease at a mid-point in time after standing up from lying down. Stronger heart rate reactivity responses to orthostatic challenge indicated greater protection against the presence of these chronic pain symptoms. ConclusionsThis biobehavioral protocol enables measurement of chronic pain suffering and protection in three dimensions: physical, emotional, and cognitive.

Effect of formant characteristics on older listeners’ dynamic pitch perception

Previous research suggested a large inter-subject variability in dynamic pitch perception among older individuals (Souza et al., 2011). Although data from younger listeners with normal hearing indicate temporal and spectral variations in complex formant characteristics may influence dynamic pitch perception (Green et al., 2002), the present study examines this interaction in an aging population. The stimulus set includes two monophthongs that have static formant patterns and two diphthongs that have dynamic formant patterns. The fundamental frequency at the midpoint in time of each vowel is kept consistent, while the ratio of start-to-end frequency varies in equal logarithmic steps. Older adults with near-normal hearing are tested using an identification task, in which they are required to identify the pitch glide as either “rise” or “fall.” An experimental task of AX discrimination is also included to verify the identification data. Results to date show inter-subject variability in dynamic pitch perception among listeners with good static pitch perception. Better pitch glide perception with monophthong than diphthong is observed in those individuals who perform poorly in general. The findings suggest a connection between individual abilities to perceive dynamic pitch and to extract the cues from fundamental and formant frequencies. [Work supported by NIH.]

Sleep, sleep timing and chronotype in animal behaviour

In humans, sleep duration and sleep timing have been identified as interesting facets of individual differences and of personality. Sleep duration and sleep timing are different constructs. For example, compare two individuals both sleeping for 6 h: one may sleep from 2300 to 0500 hours and the other from 0100 to 0700 hours. One can assess the midpoint of sleep in these two subjects which is the midpoint in clock time between sleep onset and awakening. These ideas have already been picked up in a handful of studies. Sex differences have been found in birds in the same direction as in humans with males sleeping for less time. Contrasting effects have been found in relation to mating: in humans, late chronotype men have the highest mating success, whereas in birds, earlier chronotypes gain higher mating success. Many sleep parameters are related to assortative mating in humans and similar but weaker relationships have been found in birds. Ontogenetic studies show that sleep–wake behaviour changes during adolescence in humans. Such changes have also been found in other mammals ranging from primates to rodents. Factors determining sleep–wake patterns could be environmental, such as temperature, sunrise or sunset or even artificial light at night. Artificial lighting at night leads to an earlier wake up and singing time in blackbirds, Turdus merula, whereas light at night makes humans wake up later. As a conclusion, I show some parallels and differences in the study of sleep timing between animals and humans and encourage further studies, in both field and laboratory settings.

The effect of aging on the incidence of Kaposi's sarcoma among HIV-positive individuals with known dates of seroconversion.

In the general population, the incidence of the most common types of cancer (i.e., carcinomas of the lung, breast, colon, stomach, prostate and bladder) increases with age among both males and females and in different geographic areas.1,2 This pattern is explained by the multistage model for carcinogenesis, which posits that cancer arises as a consequence of multiple genetic hits acquired with aging.3 Alternatively, it has been hypothesized that this age-related increase in incidence can be attributed, at least in part, to the diminishing immunologic function associated with aging. However, among persons with severe immunosuppression, such as those who are iatrogenically immunosuppressed after organ transplantation or persons infected with the human immunodeficiency virus (HIV), the incidence of the most common types of cancer is no higher than that among immunocompetent persons. By contrast, the incidence of both non-Hodgkin’s lymphoma (NHL) and Kaposi’s sarcoma (KS), which are rare in immunocompetent persons younger than 40 years of age, has been reported to be quite high among persons with severe immunosuppression.4,5 KS is a mesenchymal tumor that, until the appearance of the HIV epidemic, was rare in the general population of industrialized countries; it was generally found in elderly men of Mediterranean or Eastern European origin.6 With regard to the pathogenesis of KS, an infectious agent – the human herpesvirus 8 (HHV-8)—has been isolated in all forms of the disease,7,8 and epidemiologic, serologic and molecular evidence has proved that infection with HHV-8 is necessary for the development of KS. Nonetheless, it has been difficult to determine the magnitude of the association between KS and HHV-8 infection because the currently used serologic assays are limited in terms of their sensitivity and specificity9 and because other, as yet unknown, cofactors exist that are likely to play a role in the development of KS.10,11 Given that HIV-infected individuals have been shown to live longer since highly active antiretroviral therapy (HAART) was introduced,12 it is now possible to study thoroughly the relationship among immunosuppression, aging and cancer. In a study13 that investigated whether or not aging affects the risk of developing HIV-associated KS and lung cancer, using data from the AIDS-Cancer Registry Match Study, the incidence of KS appeared to increase through 39 years of age and to decline thereafter. However, no information was available from this study on the duration of HIV infection, the level of immunosuppression or the prevalence of HHV-8 infection (i.e., the main determinant of KS8). We investigated the relationship among HIV-induced immunosuppression, aging and KS, taking into account the duration of HIV infection, the level of immunosuppression and, for a subgroup of the study population, the prevalence of HHV-8 infection. This study used data from the Italian HIV-Seroconversion Study. The Seroconversion Study, which was begun in 1987, is a prospective incident cohort study of HIV seroconverters who belong to different HIV exposure categories and for whom it is possible to estimate the date of seroconversion with a certain degree of accuracy, specifically, persons for whom the results of a negative HIV test followed by a positive test within 24 months are available; the date of seroconversion is estimated as the midpoint in time between the most recent negative HIV test result and the first positive result. A detailed description of the Seroconversion Study has been published elsewhere.14,15 Residual sera samples for detection of antibodies against HHV-8 were available for some of the individuals enrolled as of June 1996 in the Seroconversion Study. A single HHV-8 serologic measurement was performed: the median time that had elapsed from the date of HIV seroconversion to the date of HHV-8 testing was 0.7 years (interquartile range: 0.4–1.6 years). HHV-8 seropositivity was determined by HHV-8 lytic antigens, using an immunofluoroscence assay with a body cavity B-cell lymphoma cell line. A detailed description of the methodology used has been reported elsewhere.16 For the present analysis, we applied the Kaplan-Meier method and the Cox proportional hazards model.17 The date of HIV seroconversion was considered time-zero of the analyses, and KS was considered the end point. In particular, we estimated the KS-free survival time as the time that had elapsed from the date of HIV seroconversion to the date of diagnosis of KS (independently of whether or not it was the first AIDS-defining disease), or the date of death or the end of the study (i.e., December 2000). The

Direct comparison of time to AIDS and infectious disease death between HIV seroconverter injection drug users in Italy and the United States: results from the ALIVE and ISS studies. AIDS Link to Intravenous Experiences. Italian Seroconversion Study.

To compare the rate of HIV disease progression in a sample of polydrug injectors (AIDS Link to Intravenous Experiences [ALIVE] study) with that in a sample of predominantly opiate injectors (Italian Seroconversion Study [ISS]). Prospective cohort studies of HIV-positive individuals whose date of seroconversion (SC) is known with a good degree of precision. The ALIVE study involves a community-based cohort of injection drug users (IDU) in the United States and the ISS reports on a clinic-based cohort of seroconverters in Italy with different exposure modalities to HIV. Data from the two cohorts were combined. The date of SC was estimated as the midpoint in time between the last negative and the first positive HIV test. Time-to-event (i.e., AIDS or death from an infectious disease) statistical methods were used. Relative hazards (RH) of progression to event were adjusted by age at SC, gender, and year of SC. Of the 1003 IDUs (251 from ALIVE and 752 from ISS), 226 progressed to AIDS, and 146 died after AIDS or from an infectious disease; of these, 10 were without an AIDS diagnosis. The two groups of IDUs differed in terms of age at SC (median, 35 years for ALIVE and 25 years for ISS), proportion of women (24% versus 31%), race (7.6% versus 100% white), and year of seroconversion (i.e., ISS participants seroconverted, on average, earlier than ALIVE participants). Although the univariate analysis suggested possible differences for progression to AIDS, or to death from infectious disease between cohorts, multivariate analyses that adjusted for age showed no significant differences by cohort, gender, race, or time of seroconversion. The median time to AIDS for 25-year-old persons was 12.3 years for ALIVE and 11.8 years for ISS; for 35-year-old persons, it was 8.5 and 8.2 years, respectively. These estimates were similar to those for non-IDUs observed in the ISS and to those from large cohort of homosexual men. Our results confirm the importance of accounting for age when considering the incubation period for HIV infection. Despite differences in drug use characteristics, the similar median times to AIDS, for each age, between the two cohorts of IDUs and between the IDUs and the non-IDUs suggest a negligible effect of injection drug use on HIV progression.

Cancer incidence in a cohort of human immunodeficiency virus seroconverters

BACKGROUND In addition to Kaposi's sarcoma and non-Hodgkin's lymphomas, it has been postulated that human immunodeficiency virus (HIV) infection may increase the risk of other cancers. The aim of the current study was to compare incidence rates of cancer among individuals who seroconverted for HIV infection with the rates in the general population of Italy. METHODS This study is part of an ongoing cohort investigation conducted by the HIV Italian Seroconversion Study Group. The study has enrolled 1255 individuals (906 males and 349 females) between the ages of 20 and 49 years who are at risk for HIV infection and have had a documented negative HIV test followed by a positive test. For each individual, the midpoint in time between the negative and positive tests was used to estimate the seroconversion date. The person-years at risk for cancer were then computed from the midpoint date to the last follow-up date or to death, and the number of cases of cancer observed in the cohort was compared with the expected number, based on rates among the general population of the same age and gender. Standardized incidence ratios (SIR) and 95% confidence intervals (CI) were computed. RESULTS A total of 58 cases of cancer were observed in the cohort. In comparison with rates in the general population, Kaposi's sarcoma was 1051 times more frequent, and non-Hodgkin's lymphomas were 157 times more frequent. Hodgkin's disease was observed in 3 men (i.e., 38 times more often in the cohort of HIV seroconverters [95% CI, 8-111]), in particular among homosexual men (SIR = 103). One woman developed stomach carcinoma. CONCLUSIONS The findings of the current incidence study are in agreement with previous studies showing excesses of Kaposi's sarcoma and non-Hodgkin's lymphomas in HIV-positive individuals. In addition, the findings suggest an association of HIV infection with Hodgkin's disease. Whether Hodgkin's disease in HIV-infected individuals should be considered an AIDS-defining illness is a question that is worthy of attention. Cancer 1997; 79:1004-8. © 1997 American Cancer Society.

Cancer incidence in a cohort of human immunodeficiency virus seroconverters. HIV Italian Seroconversion Study Group.

In addition to Kaposi's sarcoma and non-Hodgkin's lymphomas, it has been postulated that human immunodeficiency virus (HIV) infection may increase the risk of other cancers. The aim of the current study was to compare incidence rates of cancer among individuals who seroconverted for HIV infection with the rates in the general population of Italy. This study is part of an ongoing cohort investigation conducted by the HIV Italian Seroconversion Study Group. The study has enrolled 1255 individuals (906 males and 349 females) between the ages of 20 and 49 years who are at risk for HIV infection and have had a documented negative HIV test followed by a positive test. For each individual, the midpoint in time between the negative and positive tests was used to estimate the seroconversion date. The person-years at risk for cancer were then computed from the midpoint date to the last follow-up date or to death, and the number of cases of cancer observed in the cohort was compared with the expected number, based on rates among the general population of the same age and gender. Standardized incidence ratios (SIR) and 95% confidence intervals (CI) were computed. A total of 58 cases of cancer were observed in the cohort. In comparison with rates in the general population, Kaposi's sarcoma was 1051 times more frequent, and non-Hodgkin's lymphomas were 157 times more frequent. Hodgkin's disease was observed in 3 men (i.e., 38 times more often in the cohort of HIV seroconverters [95% CI, 8-111]), in particular among homosexual men (SIR = 103). One woman developed stomach carcinoma. The findings of the current incidence study are in agreement with previous studies showing excesses of Kaposi's sarcoma and non-Hodgkin's lymphomas in HIV-positive individuals. In addition, the findings suggest an association of HIV infection with Hodgkin's disease. Whether Hodgkin's disease in HIV-infected individuals should be considered an AIDS-defining illness is a question that is worthy of attention.

Histamine concentration in menstrual and peripheral blood from patients with normal menstrual blood loss and in dysfunctional menstrual bleeding

SummaryMenstrual blood was collected from the uterus within the first 48 hours of the onset of menstrual bleeding from Group 1 (menstrual blood loss 80 ml; n = 20). A peripheral blood sample was collected to coincide with the mid-point in time of the menstrual sample collection. Extracted histamine was condensed to form a fluorophore and its fluorescence was measured by spectrofluorometry. The histamine levels in ng/ml (mean value ± s.d.) for Group 1 were 75.5 ± 34.4 for menstrual blood and 39.6 ± 12.8 for peripheral blood. For Group 2 the histamine levels in menstrual blood were 76.3 ± 33.4 and those for peripheral blood 41.1 ± 14.7. Histamine concentrations for plasma from menstrual blood from both groups were found to be higher than those for peripheral blood (P < 0.0001). No differences were observed between the two groups.

Use of respiratory‐cardiovascular responses of rainbow trout (Salmo gairdneri) in identifying acute toxicity syndromes in fish: Part 2. malathion, carbaryl, acrolein and benzaldehyde

AbstractAn in vivo fish model was used to monitor the respiratory‐cardiovascular responses of individual spinally transected rainbow trout exposed to acutely toxic aqueous concentrations of two acetylcholinesterase (AChE) inhibitors, malathion and carbaryl, and two mucous membrane irritants, acrolein and benzaldehyde. The most striking changes in respiratory‐cardiovascular physiology noted on malathion and carbaryl exposures were immediate decreases in oxygen utilization (U) and heart rate (HR). Ventilation volume (VG) increased to compensate for the lower U, but not enough to increase oxygen consumption (VO2). Blood responses in carbaryl‐exposed trout differed from those in the malathion group; there were increased hematocrit (Hct) and hemoglobin (Hb) values along with an extensive drop in arterial pH (pHa) and total arterial carbon dioxide (TaCO2). The overall respiratory‐cardiovascular responses of the rainbow trout to acrolein and benzaldehyde intoxication represent a direct effect of the chemical at the respiratory surface. A steady increase in cough rate (CR) was recorded for fish exposed to both chemicals throughout exposures. A moderate to low increase in VG and VO2 was followed at 50 to 60% survival time by sudden decreases in VG and VO2 until death. Ventilation rate (VR), U and HR showed a steady downward trend over the entire survival period. After the midpoint in survival time, total arterial oxygen (TaO2), (TaCO2) and pHa all decreased, while Hct increased steadily. Individual principal components analyses of the cardiovascular‐respiratory responses of fish exposed to the four chemicals showed that the variables were highly correlated and that the first two principal components explained 55 to 70% of the variation in the 18 parameters analyzed. A two‐dimensional diagram of the first two principal components illustrated this multivariate response and the increased variability in the responses of exposed fish as compared with the control fish. Sets of toxic responses were developed to describe two new fish acute toxicity syndromes (FATS), one for AChE inhibitors and one for respiratory irritants. These were combined with the FATS for respiratory uncouplers and narcotics from previous work prior to discriminant function analysis (DFA). DFA was used to predict the specific FATS for a chemical based on the cardiovascular‐respiratory responses observed during intoxication. DFA on these responses resulted in a 100% correct separation of four specific FATS for all 32 trout tested. Of the 18 responses monitored and used in the DFA, CR, VO2, TaO2, pHa and U were the best discriminators in predicting the correct FATS for each fish.

Comparison of isotopic and chromatographic methods for estimating fecal bile acids

Isotopic and Chromatographic methods for estimating fecal bile acids were compared in ten subjects undergoing cholesterol balance studies. The subjects consumed solid food diets of constant composition. They were given intravenous injections of radioactive cholesterol 4 to 6 weeks earlier and the decline in plasma cholesterol specific activity had become exponential before the studies were begun. The specific activity values of different bile acids present in the feces were the same and were 3 ± 5% greater than the specific activity of plasma cholesterol. However the values of plasma cholesterol specific activity 56 h before the midpoint in time of collection of fecal pools was equal to the specific activity of fecal bile acids. The correlation between the amounts estimated by the Chromatographic method and those obtained by using plasma cholesterol specific activity 56 h before the midpoint in time of fecal collections was excellent ( r = 0.98). These studies on over 100 fecal pools suggested that the isotopic methods for estimating fecal bile acids are quite adequate for most clinical studies.