158 research outputs found
The prevalence of foodborne pathogenic bacteria on cutting boards and their ecological correlation with background biota
This study implemented the pyrosequencing technique and real-time quantitative PCR to determine the prevalence of foodborne pathogenic bacteria (FPB) and as well as the ecological correlations of background biota and FPB present on restaurant cutting boards (CBs) collected in Seri Kembangan, Malaysia. The prevalence of FPB in high background biota (HBB) was lower (0.24%) compared to that of low background biota (LBB) (0.54%). In addition, a multiple linear regression analysis indicated that only HBB had a significant ecological correlation with FPB. Furthermore, statistical analysis revealed that the combinations of Clostridiales, Flavobacteriales, and Lactobacillales orders in HBB had significant negative associations with FPB, suggesting that these bacteria may interact to ensure survivability and impair the growth of pathogenic bacteria
Metasurface-Enabled Multifunctional Single-Frequency Sensors without External Power
IoT sensors are crucial for visualizing multidimensional and multimodal
information and enabling future IT applications/services such as cyber-physical
space, digital twins, autonomous driving, smart cities, and virtual/augmented
reality (VR or AR). However, IoT sensors need to be battery-free to
realistically manage and maintain the growing number of available sensing
devices. Here, we provide a novel sensor design approach that employs
metasurfaces to enable multifunctional sensing without requiring an external
power source. Importantly, unlike existing metasurface-based sensors, our
metasurfaces can sense multiple physical parameters even at a fixed frequency
by breaking classic harmonic oscillations in the time domain, making the
proposed sensors viable for usage with limited frequency resources. Moreover,
we provide a method for predicting physical parameters using the machine
learning-based approach of random forest regression. The sensing performance
was confirmed by estimating temperature and light intensity, and excellent
determination coefficients larger than 0.96 were achieved. Our study affords
new opportunities for sensing multiple physical properties without relying on
an external power source or needing multiple frequencies, which markedly
simplifies and facilitates the design of next-generation wireless communication
systems.Comment: 47 pages, 23 figure
Bacterial community shift for monitoring the co-composting of oil palm empty fruit bunch and palm oil mill effluent anaerobic sludge
A recently developed rapid co-composting of oil palm empty fruit bunch (OPEFB) and palm oil mill effluent (POME) anaerobic sludge is beginning to attract attention from the palm oil industry in managing the disposal of these wastes. However, a deeper understanding of microbial diversity is required for the sustainable practice of the co-compositing process. In this study, an in-depth assessment of bacterial community succession at different stages of the pilot scale co-composting of OPEFB-POME anaerobic sludge was performed using 454-pyrosequencing, which was then correlated with the changes of physicochemical properties including temperature, oxygen level and moisture content. Approximately 58,122 of 16S rRNA gene amplicons with more than 500 operational taxonomy units (OTUs) were obtained. Alpha diversity and principal component analysis (PCoA) indicated that bacterial diversity and distributions were most influenced by the physicochemical properties of the co-composting stages, which showed remarkable shifts of dominant species throughout the process. Species related to Devosia yakushimensis and Desemzia incerta are shown to emerge as dominant bacteria in the thermophilic stage, while Planococcus rifietoensis correlated best with the later stage of co-composting. This study proved the bacterial community shifts in the co-composting stages corresponded with the changes of the physicochemical properties, and may, therefore, be useful in monitoring the progress of co-composting and compost maturity
Genome-wide Analysis of Chlamydophila pneumoniae Gene Expression at the Late Stage of Infection
Chlamydophila pneumoniae, an obligate intracellular eubacterium, changes its form from a vegetative reticulate body into an infectious elementary body during the late stage of its infection cycle. Comprehension of the molecular events in the morphological change is important to understand the switching mechanism between acute and chronic infection, which is deemed to relate to the pathogenesis of atherosclerosis. Herein, we have attempted to screen genes expressed in the late stage with a genome-wide DNA microarray, resulting in nomination of 17 genes as the late-stage genes. Fourteen of the 17 genes and six other genes predicted as late-stage genes were confirmed to be up-regulated in the late stage with a quantitative reverse transcriptase–polymerase chain reaction. These 20 late-stage genes were classified into two groups by clustering analysis: ‘drastically induced’ and ‘moderately induced’ genes. Out of eight drastically induced genes, four contain σ28 promoter-like sequences and the other four contain an upstream common sequence. It suggests that besides σ28, there are certain up-regulatory mechanisms at the late stage, which may be involved in the chlamydial morphological change and thus pathogenesis
Theracurmin inhibits intestinal polyp development in Apc‐mutant mice by inhibiting inflammation‐related factors
Colorectal cancer (CRC) is the second leading cause of cancer death worldwide. Therefore, it is important to establish useful methods for preventing CRC. One prevention strategy involves the use of cancer chemopreventive agents, including functional foods. We focused on the well‐known cancer chemopreventive agent curcumin, which is derived from turmeric. However, curcumin has the disadvantage of being poorly soluble in water due to its high hydrophobicity. To overcome this problem, the formation of submicron particles with surface controlled technology has been applied to curcumin to give it remarkably improved water solubility, and this derived compound is named Theracurmin. To date, the preventive effects of Theracurmin on hereditary intestinal carcinogenesis have not been elucidated. Thus, we used Apc‐mutant mice, a model of familial adenomatous polyposis, to evaluate the effects of Theracurmin. First, we showed that treatment with 10‐20 µM Theracurmin for 24 hours reduced nuclear factor‐κB (NF‐κB) transcriptional activity in human colon cancer DLD‐1 and HCT116 cells. However, treatment with curcumin mixed in water did not change the NF‐κB promoter transcriptional activity. As NF‐κB is a regulator of inflammation‐related factors, we next investigated the downstream targets of NF‐κB: monocyte chemoattractant protein‐1 (MCP‐1) and interleukin (IL)‐6. We found that treatment with 500 ppm Theracurmin for 8 weeks inhibited intestinal polyp development and suppressed MCP‐1 and IL‐6 mRNA expression levels in the parts of the intestine with polyps. This report provides a proof of concept for the ongoing Theracurmin human trial (J‐CAP‐C study)
Effect of oxygen in shielding gas on weldability in plasma-GMA hybrid welding process of high-tensile strength steel
The version of record of this article, first published in International Journal of Advanced Manufacturing Technology, is available online at Publisher’s website: https://doi.org/10.1007/s00170-024-14100-x.This study aims to clarify the effect of oxygen in shielding gas on weldability in the plasma-GMA (Gas Metal Arc) hybrid welding process of high-tensile strength steel plates. The difference in keyhole profile and bead formation, when the GMA shielding gas was pure Ar, Ar + 2% O₂ or Ar + 20% CO₂, was investigated for plate thicknesses of 6 and 9 mm for the first time. It was found that the weld beads were in good condition for 6 mm thickness plates for all shielding gases, which implied that the window of welding conditions for this thickness is wide. In contrast, for 9 mm thickness plates, a fully penetrated weld bead was achieved only in Ar + 20% CO₂, and weld bead penetration in Ar + 20% CO₂ is higher than in pure Ar and Ar + 2% O₂ in the same welding condition. Due to decreased surface tension caused by sufficiently increased oxygen absorbed into the weld pool, the keyhole diameter increased to penetrate the bottom side of the plate, and the depressing weld pool surface under GMA allowed the heat input from the GMA to be directly applied to a deeper position. Consequently, the plasma-GMA hybrid welding process with Ar + 20% CO₂ achieved a complete penetration for a plate of 9 mm thickness, owing to the effects of both phenomena. It proved a potential to increase penetrability in welding thicker plates by controlling oxygen content in shielding gas of GMA adequately
Long-Term Density Trend in the Mesosphere and Lower Thermosphere from Occultations of the Crab Nebula with X-Ray Astronomy Satellites
We present long-term density trends of the Earth's upper atmosphere at
altitudes between 71 and 116 km, based on atmospheric occultations of the Crab
Nebula observed with X-ray astronomy satellites, ASCA, RXTE, Suzaku, NuSTAR,
and Hitomi. The combination of the five satellites provides a time period of 28
yr from 1994 to 2022. To suppress seasonal and latitudinal variations, we
concentrate on the data taken in autumn (49< doy <111) and spring (235< doy
<297) in the northern hemisphere with latitudes of 0--40 degrees. With this
constraint, local times are automatically limited either around noon or
midnight. We obtain four sets (two seasons times two local times) of density
trends at each altitude layer. We take into account variations due to a linear
trend and the 11-yr solar cycle using linear regression techniques. Because we
do not see significant differences among the four trends, we combine them to
provide a single vertical profile of trend slopes. We find a negative density
trend of roughly -5 %/decade at every altitude. This is in reasonable agreement
with inferences from settling rate of the upper atmosphere. In the 100--110 km
altitude, we found an exceptionally high density decline of about -12 %/decade.
This peak may be the first observational evidence for strong cooling due to
water vapor and ozone near 110 km, which was first identified in a numerical
simulation by Akmaev et al. (2006). Further observations and numerical
simulations with suitable input parameters are needed to establish this
feature.Comment: 38 pages, 9 figures, accepted for publication in Journal of
Geophysical Research - Space Physic
L-Leucine increases the daily body temperature and affords thermotolerance in broiler chicks
Objective Heat stress poses an increasing threat for poultry production. Some amino acids have been found to play critical roles in affording thermotolerance. Recently, it was found that in ovo administration of L-leucine (L-Leu) altered amino acid metabolism and afforded thermotolerance in heat-exposed broiler chicks. Methods In this study, two doses (35 and 70 μmol/egg) of L-Leu were administered in ovo on embryonic day 7 to determine their effect on rectal temperature (RT), body weight (BW) and thyroid hormones at hatching. Changes in RT, BW, and thermotolerance in post-hatched chicks were also analyzed. Results It was found that in ovo administration of L-Leu dose-dependently reduced RT and plasma thyroxine (T4) level just after hatching. In post-hatched neonatal broiler chicks, however, the higher dose of L-Leu administered in ovo significantly increased RT without affecting BW gain. In chicks that had been exposed to heat stress, the RT was significantly lowered by in ovo administration of L-Leu (high dose) in comparison with the control chicks under the same high ambient temperature (HT: 35°C±1°C, 120 min). Conclusion In ovo administration of L-Leu in a high dose contributed to an increased daily body temperature and afforded thermotolerance under HT in neonatal broiler chicks
The Prognosis for Unexpected Gallbladder Carcinoma with Bile Spillage during Laparoscopic Cholecystectomy
Here we review the prognosis of patients with unsuspected gallbladder carcinoma(GBC), detected after laparoscopic cholecystectomy(LC)in a single institute. We reviewed the medical records of patients diagnosed with gallbladder stones on admission, who underwent LC. Carcinoma involving the gallbladder was found in 22 of 2,770 patients(0.9%)via postoperative pathological examination. This GBC group spanned 58-87 years of age(mean, 75 years; 13 females and 9 males). The preoperative diagnosis was gallbladder stones with acute/chronic cholecystitis or adenomyomatosis of the gallbladder in all patients. We performed an additional surgery in 6 of 15 patients with pT2 and T3 disease; of these, 3 patients with pT2 disease and 1 with pT3 experienced bile spillage during the LC. The mean survival of patients with unexpected GBC was 21 months, with bile spillage occurring as a complication of LC identified as a potential risk factor for shorter survival(15.3 vs. 32.5 months). We identified patients with pT2 and pT3 disease after LC, and two patients with pT2 and 1 with pT3 who had bile spillage during LC died of peritoneal dissemination within 28 months, despite additional surgery. Occasional seeding caused by bile spillage during LC should be carefully avoided to minimize the risk of developing unsuspected GBC after LC
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