Erratum: Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande [Phys. Rev. Lett. 130, 031802 (2023)].

This corrects the article DOI: 10.1103/PhysRevLett.130.031802.

Search for Cosmic-Ray Boosted Sub-GeV Dark Matter Using Recoil Protons at Super-Kamiokande.

We report a search for cosmic-ray boosted dark matter with protons using the 0.37 megaton×years data collected at Super-Kamiokande experiment during the 1996-2018 period (SKI-IV phase). We searched for an excess of proton recoils above the atmospheric neutrino background from the vicinity of the Galactic Center. No such excess is observed, and limits are calculated for two reference models of dark matter with either a constant interaction cross section or through a scalar mediator. This is the first experimental search for boosted dark matter with hadrons using directional information. The results present the most stringent limits on cosmic-ray boosted dark matter and exclude the dark matter-nucleon elastic scattering cross section between 10^{-33}cm^{2} and 10^{-27}cm^{2} for dark matter mass from 1 MeV/c^{2} to 300 MeV/c^{2}.

Baseline bio-accumulation concentrations and resulting oxidative stress in Synodontis zambezensis after an acute laboratory exposure to 4,4'-DDT.

The use of 1,1'-(2,2,2-Trichloro-1,1-ethanediyl)bis(4-chlorobenzene) (DDT) as a pesticide for the control of insects vectors responsible for the spread of many life threatening diseases was officially banned in 1972 by the United States Environmental Protection Agency (USEPA). It was banned throughout the world, in most developed countries, because of the toxic effects it causes in wildlife, including birds and fish. However, DDT is still used in approximately 43 African countries, including South Africa, to control the spread of malaria. The lipophilic nature of DDT and therefore its persistence in the environment makes it extremely important for laboratory based studies to be conducted in an effort to evaluate the accumulation potential and possible physiological effects of DDT in aquatic organisms under controlled conditions. The aim of this study was to establish baseline bioaccumulation concentrations within Synodontis zambezensis following an acute exposure to 4,4'-DDT. The three metabolites analysed were 4,4'-DDE, 4,4'-DDD and 4,4'-DDT. None of the 2,4'-isomers were analysed in this study since the acute exposure used a solution of 98.7% pure 4,4'-DDT (Sigma-Aldrich PESTANAL®, Analytical Standard, CAS-No 50-29-3, Batch number SZBE057XV) and not a mixture of 4,4'-DDT and 2,4'-DDT as found in technical grade DDT. Soxhlet extraction of tissue samples and liquid/liquid extraction of water samples followed by analysis through Gas-chromatography mass-spectrophotometry was completed. Mean 4,4'-DDE, 4,4'-DDD and 4,4'-DDT concentrations ranged from 15.34 ng/g to 45.34 ng/g, 28.16 ng/g to 63.25 ng/g and 28.64 ng/g to 96.21 ng/g respectively. All of the accumulated concentrations fell within environmentally relevant concentrations with no input through the food web. The accumulated concentrations of 4,4'-DDT and its three metabolites resulted in oxidative stress responses within the gills and the liver tissue of S. zambezensis. Significant differences (p ≤ .05) were observed between malondialdehyde (MDA) and reduced glutathione (GSH) within the liver and in superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) in the gills.

Evidence of impacts from DDT in pelican, cormorant, stork, and egret eggs from KwaZulu-Natal, South Africa.

DDT remains in use for malaria control in South Africa. We quantified DDTs in aquatic bird eggs from the highly biodiverse northern KwaZulu-Natal, a province of South Africa where DDT has been used for more than 80 years for malaria control. Pelican eggs had the highest ΣDDT concentration (7200 ng/g lipid mass; lm), Little Egret eggs had 6900 ΣDDT lm, African Openbill eggs had 3400 ng/g lm ΣDDT, and White-breasted Cormorant had 2400 ng/g lm. All species had non-significantly different mean concentrations of o,p'-DDT, p,p'-DDT, and ΣDDT, but with significant differences for p,p-DDE, o,p'-DDD, p,p'-DDD, %DDT, %DDD, and %lipid. The thinnest pelican eggshell (0.40 mm) had a ΣDDT concentration of 3300 ng/g lm.; the thickest shell (0.96 mm) had the lowest ΣDDT concentration at 29 ng/g lm; a 58% difference. Linear regressions of concentrations with shell thickness for the pelican eggs were significant for p,p'-DDE and p,p'-DDD, indicating risk of reproductive impairment. Compositional profiles indicate different food webs for the different species. DDT concentrations were lower than from another DDT-sprayed locality in South Africa, possible linked to differences in hydrology and rainfall. We conclude that significant ecotoxic threats associated with DDT remain in this area, and possibly threatens birds from less polluted areas. Our findings suggest continued negative human health and environmental impacts from DDT. There is an urgency to move away from DDT as quickly as possible; alternatively, to implement practices that prevent emissions of DDT to the environment while protecting human life.

Biotransport of metallic trace elements from marine to terrestrial ecosystems by seabirds.

Physical systems, such as currents and winds, have traditionally been considered responsible for transporting contaminants. Although evidence is mounting that animals play a role in this process through their movements, we still know little about how such contaminant biotransport occurs and the extent of effects at deposition sites. In the present study, we address this question by studying how rhinoceros auklets (Cerorhinca monocerata), a seabird that occurs in immense colonies (∼300 000 pairs at our study site, Teuri Island), affect contaminant levels at their colony and at nearby sites. More specifically, we hypothesize that contaminants are transported and deposited by seabirds at their colony and that these contaminants are passed on locally to the terrestrial ecosystem. To test this hypothesis, we analyzed the concentration of 9 heavy metal and metalloids, as well as δ13 C and δ15 N stable isotopes, in bird tissues, plants, and soil, both within and outside of the colony. The results show that rhinoceros auklets transport marine-derived mercury (Hg), possibly from their wintering location, and deposit Hg via their feces at their breeding site, thereby contaminating plants and soils within the breeding colony. The present study confirms not only that animals can transport contaminants from marine to terrestrial ecosystems, potentially over unexpectedly long distances, but also that bird tissues contribute locally to plant contamination. Environ Toxicol Chem 2019;38:106-114. © 2018 SETAC.

Search for Boosted Dark Matter Interacting with Electrons in Super-Kamiokande.

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

Disruption of the pacemaker activity of interstitial cells of Cajal via nitric oxide contributes to postoperative ileus.

BACKGROUND: Interstitial cells of Cajal (ICC) serve as intestinal pacemakers. Postoperative ileus (POI) is a gastrointestinal motility disorder that occurs following abdominal surgery, which is caused by inflammation-induced dysfunction of smooth muscles and enteric neurons. However, the participation of ICC in POI is not well understood. In this study, we investigated the functional changes of ICC in a mouse model of POI. METHODS: Intestinal manipulation (IM) was performed to induce POI. At 24 h or 48 h after IM, the field potential of the intestinal tunica muscularis was investigated. Tissues were also examined by immunohistochemistry and electron microscopic analysis. KEY RESULTS: Gastrointestinal transit was significantly decreased with intestinal tunica muscularis inflammation at 24 h after IM, which was ameliorated at 48 h after IM. The generation and propagation of pacemaker potentials were disrupted at 24 h after IM and recovered to the control level at 48 h after IM. ICC networks, detected by c-Kit immunoreactivity, were remarkably disrupted at 24 h after IM. Electron microscopic analysis revealed abnormal vacuoles in the ICC cytoplasm. Interestingly, the ICC networks recovered at 48 h after IM. Administration of aminoguanidine, an inducible nitric oxide synthase inhibitor, suppressed the disruption of ICC networks. Ileal smooth muscle tissue cultured in the presence of nitric oxide donor, showed disrupted ICC networks. CONCLUSIONS AND INFERENCES: The generation and propagation of pacemaker potentials by ICC are disrupted via nitric oxide after IM, and this disruption may contribute to POI. When inflammation is ameliorated, ICC can recover their pacemaker function.

Human Health Risk from Consumption of Marine Fish Contaminated with DDT and Its Metabolites in Maputo Bay, Mozambique.

Many countries with incidence of malaria, including those surrounding Maputo Bay, use dichloro-diphenyl-trichloroethane (DDT) to reduce mosquitoes. This study is the first to estimate the human health risk associated with consumption of marine fish from Maputo Bay contaminated with DDTs. The median for ∑DDTs was 3.8 ng/g ww (maximum 280.9 ng/g ww). The overall hazard ratio for samples was 1.5 at the 75th percentile concentration and 28.2 at the 95th percentile. These calculations show increased potential cancer risks due to contamination by DDTs, data which will help policy makers perform a risk-benefit analysis of DDT use in malaria control programs in the region.

A glycomics approach to discover novel renal biomarkers in birds by administration of cisplatin and diclofenac to chickens.

Avian species have a unique renal structure and abundant blood flow into the kidneys. Although many birds die due to nephrotoxicity caused by chemicals, there are no early biomarkers for renal lesions. Uric acid level in blood, which is generally used as a renal biomarker, is altered when the kidney function is damaged by over 70%. Therefore, early biomarkers for kidney injury in birds are needed. In humans, glycomics has been at the forefront of biological and medical sciences, and glycans are used as biomarkers of diseases, such as carcinoma. In this study, a glycomics approach was used to screen for renal biomarkers in chicken. First, a chicken model of kidney damage was generated by injection of diclofenac or cisplatin, which cause acute interstitial nephritis (AIN) and acute tubular necrosis (ATN), respectively. The nephrotoxicity levels were determined by a blood chemical test and histopathological analysis. The plasma N-glycans were then analyzed to discover renal biomarkers in birds. Levels of 14 glycans increased between pre- and post administration in kidney-damaged chickens in the diclofenac group, and some of these glycans had the same presumptive composition as those in human renal carcinoma patients. Glycan levels did not change remarkably in the cisplatin group. It is possible that there are changes in glycan expression due to AIN, but they do not reflect ATN. Although further research is needed in other species of birds, glycans are potentially useful biomarkers for AIN in avian species.

Systematic review with meta-analysis: performance of dried blood spots for hepatitis C antibodies detection.

OBJECTIVES: Dried blood spots (DBS) specimens can be used for hepatitis C virus (HCV) infection screening in cases where serum specimens are difficult to obtain. However, uncertainties surround the sensitivity and specificity of DBS for HCV antibodies (anti-HCV) serology testing. We aimed to evaluate the accuracy of DBS use to screen for HCV infection. STUDY DESIGN: We carried out a systematic review and meta-analysis. METHODS: Medline and EMBASE databases were searched for articles published between 1989 and November 2016. We included studies comparing DBS to plasma/serum specimens to detect anti-HCV in adults. Two authors extracted data and assessed the quality of the studies using an adapted standards for reporting diagnostic accuracy studies (STARD) and independently checked the data for accuracy. Meta-analysis was computed with the bivariate and the hierarchical summary receiver-operating characteristic models. RESULTS: Twelve studies (3307 specimens) were analyzed, where 11 of them evaluated the anti-HCV using enzyme immunoassays (EIAs), and the remaining one used rapid diagnostic tests. The studies were mostly case-controls (83.3%) and from developed countries (66.7%). The overall pooled sensitivity (95% confidence interval; CI) and specificity (95% CI) of DBS to detect anti-HCV was 98.1% (96.1-99.1%) and 99.7% (98.9-99.9%), respectively. In studies using EIAs, the pooled sensitivity and specificity were 97.3% (94.3-98.8%) and 99.6% (98.5-99.9%), respectively. Considering only studies using EIAs, sensitivity analysis excluding one study carried out in people who inject drugs showed the pooled sensitivity of 97.8% (96.2-98.8%) and specificity of 99.5% (98.5-99.9%). CONCLUSIONS: In testing for anti-HCV by means of EIAs, the efficacy of DBS is found to be similar or slightly lower than that of serum specimens. However, the risk of finding negative and positive results that are both false when using DBS remains present. Therefore, further work including optimal storage and processing methodologies are recommended. This is to help establish consensus guidelines for use of DBS specimens for anti-HCV screening.

Concentrations and human health risk assessment of DDT and its metabolites in free-range and commercial chicken products from KwaZulu-Natal, South Africa.

Organochlorine pesticides such as dichlorodiphenyltrichloroethane (DDT) have been used in agriculture and for disease control purposes over many decades. Reports suggest that DDT exposure may result in a number of adverse effects in humans. In the KwaZulu-Natal Province of South Africa, DDT is sprayed annually in homes (indoor residual spraying) to control the mosquito vector of malaria. In the northern part of the Province, samples of free-range chicken meat (n = 48) and eggs (n = 13), and commercially produced chicken meat (n = 6) and eggs (n = 11), were collected and analysed. Of the free-range chicken meat samples, 94% (45/48) contained DDTs (ΣDDTs median 6.1 ng/g wet weight [ww], maximum 79.1 ng/g ww). Chicken egg contents were also contaminated (ΣDDTs in free-range eggs median 9544 ng/g ww, maximum 96.666 ng/g ww; and in commercial eggs median 1.3 ng/g ww, maximum 4.6 ng/g ww). The predominant DDT congener detected was p,p'-DDE in both free-range meat (>63%) and eggs (>66%), followed by p,p'-DDT and then p,p'-DDD. Based on estimated daily intake values, calculated human risk ratio (carcinogenic) values were >1 for DDTs detected in both free-range chicken products. Consumption of free-range eggs poses a particularly high health risk.

Lip b 1 is a novel allergenic protein isolated from the booklouse, Liposcelis bostrychophila.

BACKGROUND: Booklice, belonging to the order Psocoptera, are small household insect pests that are distributed worldwide. Liposcelis bostrychophila, a common home-inhabiting species of booklouse, infests old books, sheets of paper, and stored food. Recent entomological and serological studies demonstrated that L. bostrychophila accounted for the majority of detectable insects in house dust and could be a potent inducer of respiratory allergy. Our recent proteomic analysis identified a potent allergenic protein from L. bostrychophila, designated Lip b 1, and determined its partial amino acid sequences. METHODS: Cloning of cDNAs for Lip b 1 was performed by large-scale transcriptome analysis (RNA-seq) and subsequent reverse transcription polymerase chain reaction. The full-length amino acid sequences deduced from Lip b 1 cDNAs were bioinformatically analyzed. The recombinant proteins of glutathione S-transferase (GST)-fused Lip b 1 were analyzed by Western blot and enzyme-linked immunosorbent assay. RESULTS: Lip b 1 cDNAs encoding two types of 254-amino acid proteins were cloned. The clones shared 87% identity, and the deduced molecular weights and isoelectric points were consistent with those determined in our previous study. The two types of Lip b 1 proteins in the GST-fused form were similarly reactive with sera from allergic patients sensitized with L. bostrychophila. CONCLUSIONS: Lip b 1 is a novel protein possibly causing booklouse allergy.

Pregnancies with factor V deficiency: a case report and review of the literature.

CASE REPORT: A 30-year-old Japanese nulliparous woman visited for pregnancy at 33 weeks with a massive ovarian tumor located in the pouch of Douglas. By preoperative screening, her prothrombin time (PT) and activated partial thromboplastin time (APTT) were prolonged, and her FV activity was significantly decreased to 4.8%. After prophylactic FFP 20 ml/kg was administered and her FV factor was 19.3%, cesarean delivery was performed, and her perioperative course was uneventful. One year later, she underwent a dilatation and evacuation because of a missed abortion, although prophylactic FFP was not administered. During a third pregnancy, after prophylactic FFP 20 ml/kg was administered and FV activity increased to 21.1%, elective cesarean delivery was performed, and her postoperative course was uneventful. CONCLUSION: For surgical therapy or delivery, the goal of therapy is to maintain FV activity above 20%. It is particularly useful to administer prophylactic FFP.

Fast Heating of Imploded Core with Counterbeam Configuration.

A tailored-pulse-imploded core with a diameter of 70 µm is flashed by counterirradiating 110 fs, 7 TW laser pulses. Photon emission (>40 eV) from the core exceeds the emission from the imploded core by 6 times, even though the heating pulse energies are only one seventh of the implosion energy. The coupling efficiency from the heating laser to the core using counterirradiation is 14% from the enhancement of photon emission. Neutrons are also produced by counterpropagating fast deuterons accelerated by the photon pressure of the heating pulses. A collisional two-dimensional particle-in-cell simulation reveals that the collisionless two counterpropagating fast-electron currents induce mega-Gauss magnetic filaments in the center of the core due to the Weibel instability. The counterpropagating fast-electron currents are absolutely unstable and independent of the core density and resistivity. Fast electrons with energy below a few MeV are trapped by these filaments in the core region, inducing an additional coupling. This might lead to the observed bright photon emissions.

Foams stabilized with solid particles carrying stimuli-responsive polymer hairs.

Submicrometer-sized polystyrene (PS) particles carrying stimuli-responsive poly[2-(diethylamino)ethyl methacrylate] (PDEA) hairs with degrees of polymerization of 30, 60 and 90 were synthesized by dispersion polymerization and used as a particulate foam stabilizer. The effects of the composition of these PDEA-PS particles and foam formation conditions on foamability, foam stability and foam microstructures were extensively investigated. The hairy particles were found to work as an effective stabilizer of aqueous foams in basic media, in which the PDEA hairs are not protonated and thus the particle surfaces exhibit suitable wettability at the air-water interface. In contrast, little to no foam or unstable foams were formed in acidic aqueous media, in which the hairs are protonated and are therefore water soluble. Particles carrying longer hairs resulted in greater foamability and more highly stabilized foams that were capable of persisting for more than one month. Foams were found to form in a narrower pH range when using PS particles with longer hairs, due to both entropic and image charge effects. Data obtained from the touch mixer mixing method showed that both foamability and foam stability increased with increases in the concentration of polymer particles up to 10 wt%, because higher concentrations allowed greater air-water interfacial areas to be stabilized. Conversely, only minimal foam was obtained at and above 15 wt% because of the high viscosity of the resulting aqueous particle dispersion. Trials using the homogenizer mixing method showed that foam with a cream-like texture could be formed even at 40 wt% particle concentration as a result of the improved mixing efficiency. Defoamation could be induced by exposing the foams to HCl vapor. Exposure to acidic vapor led to in situ protonation of the 2-(diethylamino)ethyl methacrylate residues, rendering the PDEA hairs hydrophilic and water soluble, and desorption of the PDEA-PS particles from the air-water interface.

Behaviour in a standardized assay, but not metabolic or growth rate, predicts behavioural variation in an adult aquatic top predator Esox lucius in the wild.

This study tested for links among behaviour, state and life-history variables as predicted by the pace-of-life hypothesis in adult pike Esox lucius. First, a standardized open-field behavioural assay was developed to assess individual behaviour of wild-captured adult E. lucius. Behaviour within the standardized assay predicted swimming behaviour in the lake, providing an ecological validation of the assay. There was no relationship between standardized behaviour and any of the life-history and state variables, including metabolism, body condition, juvenile growth rate and adult growth rate in contrast to predictions from the pace-of-life hypothesis. This study demonstrates that it is possible to assess ecologically relevant behavioural variation in a large-bodied top predator using a standard open-field assay, but it is noteworthy that this standardized behaviour is not systematically related to standard metabolism or growth.

Characterization of equine cytochrome P450: role of CYP3A in the metabolism of diazepam.

Research on drug metabolism and pharmacokinetics in large animal species including the horse is scarce because of the challenges in conducting in vivo studies. The metabolic reactions catalyzed by cytochrome P450s (CYPs) are central to drug pharmacokinetics. This study elucidated the characteristics of equine CYPs using diazepam (DZP) as a model compound as this drug is widely used as an anesthetic and sedative in horses, and is principally metabolized by CYPs. Diazepam metabolic activities were measured in vitro using horse and rat liver microsomes to clarify the species differences in enzyme kinetic parameters of each metabolite (temazepam [TMZ], nordiazepam [NDZ], p-hydroxydiazepam [p-OH-DZP], and oxazepam [OXZ]). In both species microsomes, TMZ was the major metabolite, but the formation rate of p-OH-DZP was significantly less in the horse. Inhibition assays with a CYP-specific inhibitors and antibody suggested that CYP3A was the main enzyme responsible for DZP metabolism in horse. Four recombinant equine CYP3A isoforms expressed in Cos-7 cells showed that CYP3A96, CYP3A94, and CYP3A89 were important for TMZ formation, whereas CYP3A97 exhibited more limited activity. Phylogenetic analysis suggested diversification of CYP3As in each mammalian order. Further study is needed to elucidate functional characteristics of each equine CYP3A isoform for effective use of diazepam in horses.

Search for Nucleon and Dinucleon Decays with an Invisible Particle and a Charged Lepton in the Final State at the Super-Kamiokande Experiment.

Search results for nucleon decays p→e^{+}X, p→µ^{+}X, n→νγ (where X is an invisible, massless particle) as well as dinucleon decays np→e^{+}ν, np→µ^{+}ν, and np→τ^{+}ν in the Super-Kamiokande experiment are presented. Using single-ring data from an exposure of 273.4 kton·yr, a search for these decays yields a result consistent with no signal. Accordingly, lower limits on the partial lifetimes of τ_{p→e^{+}X}>7.9×10^{32} yr, τ_{p→µ^{+}X}>4.1×10^{32} yr, τ_{n→νγ}>5.5×10^{32} yr, τ_{np→e^{+}ν}>2.6×10^{32} yr, τ_{np→µ^{+}ν}>2.2×10^{32} yr, and τ_{np→τ^{+}ν}>2.9×10^{31} yr at a 90% confidence level are obtained. Some of these searches are novel.