Efficacy of natural killer cell therapy combined with chemoradiotherapy in murine models of head and neck squamous cell carcinoma.

BACKGROUND AIMS: Natural killer (NK) cell-based cancer immunotherapy is effective when combined with other treatment modalities such as irradiation and chemotherapy. NK cell's antitumor function to treat solid tumor, including head and neck squamous cell carcinoma (HNSCC), has been targeted recently. This study assessed NK cell recruitment in response to chemoradiation therapy (CRT) in HNSCC. METHODS: Ex vivo expansion of NK cell, flow cytometry, cell viability assay, cytotoxicity assay, immunohistochemistry, and animal model were performed. RESULTS: Mouse NK cells were recruited to the tumor site by CRT in a nude mouse model. Furthermore, expanded and activated human NK cells (eNKs) were recruited to the tumor site in response to CRT, and CRT enhanced the anti-tumor activity of eNK in an NOD/SCID IL-2Rγnull mouse model. Various HNSCC cancer cell lines exhibited different NK cell ligand activation patterns in response to CRT that correlated with NK cell-mediated cytotoxicity. CONCLUSIONS: Identifying the activation patterns of NK cell ligands during CRT might improve patient selection for adjuvant NK cell immunotherapy combined with CRT. This is the first study to investigate the NK cell's antitumor function and recruitment with CRT in HNSCC mouse model.

Microbial succession during button mushroom (Agaricus bisporus) production evaluated via high-throughput sequencing.

Button mushrooms (Agaricus bisporus), are one of the most widely consumed mushrooms in the world. However, changes within its microbial community as it relates to the use of different raw materials and cultivation methods, as well as potential points of microbial contamination throughout the production process have not been investigated extensively. In the present study, button mushroom cultivation was investigated in each of the four stages (raw materials, composting (phase I, Ⅱ, and Ⅲ), casing, and harvesting), and samples (n = 186) from mushrooms and their related environments were collected from four distinct mushroom-growing farms (A-D) in Korea. Shifts within the bacterial consortium during mushroom production were characterized with 16 S rRNA amplicon sequencing. The succession of bacterial communities on each farm was dependent on the raw material incorporated, aeration, and the farm environment. The dominant phyla of the compost stack at the four farms were Pseudomonadota (56.7%) in farm A, Pseudomonadota (43.3%) in farm B, Bacteroidota (46.0%) in farm C, and Bacillota (62.8%) in farm D. During the Phase Ⅰ, highly heat-resistant microbes, such as those from the phylum Deinococcota (0.6-65.5%) and the families Bacillaceae (1.7-36.3%), Thermaceae (0.1-65.5%), and Limnochordaceae (0.3-30.5%) greatly proliferated. The microbial diversity within compost samples exhibited a marked decline as a result of the proliferation of thermophilic bacteria. In the spawning step, there were considerable increases in Xanthomonadaceae in the pasteurized composts of farms C and D - both of which employed an aeration system. In the harvesting phase, beta diversity correlated strongly between the casing soil layer and pre-harvest mushrooms, as well as between gloves and packaged mushrooms. The results suggest that gloves may be a major source of cross-contamination for packaged mushrooms, highlighting the need for enhanced hygienic practices during the harvesting phase to ensure product safety. These findings contribute to the current understanding of the influence of environmental and adjacent microbiomes on mushroom products to benefit the mushroom industry and relevant stakeholders by ensuring quality production.

Distorted body weight perception and its gender differences in middle-aged adults: population based study.

BACKGROUND: Increasing interest in appearance and the growing preference for a beautiful body can lead to physical and psychological problems due to an inappropriate body image perception. As such, there is a need to identify what factors may contribute to an inappropriate body image. The purpose of this study was to examine the presence of distorted body weight perception among middle-aged Koreans and identify gender differences and other factors that contribute to a distorted body image regarding body weight. METHODS: Data on 8363 middle-aged adults (aged 45-64 years) from the Korea National Health and Nutrition Examination Survey were analyzed using complex samples analysis considering weight, stratification variables, and cluster variables. The difference between perceived body image regarding body weight and actual body mass index was used to assess distorted body weight perception. Socioeconomic status, health behaviors, daily energy consumption, and psychological status (depression and stress) were assessed for their relationship to distorted body weight perception. RESULTS: Results showed that a distorted body image regarding body weight was more prevalent among middle-aged men (45.3%) than women (25.7%). Age, income, perceived health status, and health behaviors were significantly associated with distorted body weight perception in middle-aged men, whereas psychological factors were associated with distorted body weight perception in middle-aged women. CONCLUSIONS: Further research on distorted body weight perception is needed to gain understanding of the gender differences between middle-aged men and women in Korea. Furthermore, to the results of the study can be used as a basis for developing various education, health mediation, and public health promotion interventions and programs to address body weight perception in middle-aged adults.

Recent Advances in the Application of Antibacterial Complexes Using Essential Oils.

Although antibacterial spectrum of essential oils (EOs) has been analyzed along with consumers' needs on natural biocides, singular treatments generally require high concentration of EOs and long-term exposures to eliminate target bacteria. To overcome these limitations, antibacterial complex has been developed and this review analyzed previous reports regarding the combined antibacterial effects of EOs. Since unexpectable combined effects (synergism or antagonism) can be derived from the treatment of antibacterial complex, synergistic and antagonistic combinations have been identified to improve the treatment efficiency and to avoid the overestimation of bactericidal efficacy, respectively. Although antibacterial mechanism of EOs is not yet clearly revealed, mode of action regarding synergistic effects especially for the elimination of pathogens by using low quantity of EOs with short-term exposure was reported. Whereas comprehensive analysis on previous literatures for EO-based disinfectant products implies that the composition of constituents in antibacterial complexes is variable and thus analyzing the impact of constituting substances (e.g., surfactant, emulsifier) on antibacterial effects is further needed. This review provides practical information regarding advances in the EO-based combined treatment technologies and highlights the importance of following researches on the interaction of constituents in antibacterial complex to clarify the mechanisms of antibacterial synergism and/or antagonism.

Molecular determinants of cadherin ideal bond formation: Conformation-dependent unbinding on a multidimensional landscape.

Classical cadherin cell-cell adhesion proteins are essential for the formation and maintenance of tissue structures; their primary function is to physically couple neighboring cells and withstand mechanical force. Cadherins from opposing cells bind in two distinct trans conformations: strand-swap dimers and X-dimers. As cadherins convert between these conformations, they form ideal bonds (i.e., adhesive interactions that are insensitive to force). However, the biophysical mechanism for ideal bond formation is unknown. Here, we integrate single-molecule force measurements with coarse-grained and atomistic simulations to resolve the mechanistic basis for cadherin ideal bond formation. Using simulations, we predict the energy landscape for cadherin adhesion, the transition pathways for interconversion between X-dimers and strand-swap dimers, and the cadherin structures that form ideal bonds. Based on these predictions, we engineer cadherin mutants that promote or inhibit ideal bond formation and measure their force-dependent kinetics using single-molecule force-clamp measurements with an atomic force microscope. Our data establish that cadherins adopt an intermediate conformation as they shuttle between X-dimers and strand-swap dimers; pulling on this conformation induces a torsional motion perpendicular to the pulling direction that unbinds the proteins and forms force-independent ideal bonds. Torsional motion is blocked when cadherins associate laterally in a cis orientation, suggesting that ideal bonds may play a role in mechanically regulating cadherin clustering on cell surfaces.

NDR-effect vertical-illumination-type Ge-on-Si avalanche photodetector.

We present the enhanced performances of a vertical-illumination-type Ge-on-Si avalanche photodetector based on internal RF-gain effects operating up to 50 Gb/s. A fabricated Ge-on-Si avalanche photodetector (APD) exhibits three operational voltage regions associated with different aspects of the current (DC) gain and bandwidth characteristics. The measured current-voltage (I-V) curve of a Ge-on-Si APD exhibits a negative photoconductance (negative differential resistance [NDR]) in a high bias region beyond the avalanche breakdown voltage (V br ), where a device shows good eye openings up to 50 Gb/s (non-return-to-zero [NRZ] signal) with further improved signal-to-noise ratios and signal amplitudes. A ROSA packaged module, wherein a fabricated Ge-on-Si APD is wire-bonded to a commercial TIA with a ∼75% optical alignment for λ∼1310 nm and biased at a lower voltage than the V br , exhibits the sensitivities of -18.9 and -15.3 dBm for 30 and 35 Gb/s, respectively, and -13.9 dBm for 40 Gb/s at a 10-12 bit error rate. The experimental results indicate that considerable improvement in a module performance can be expected by utilizing the Ge-on-Si APD operated in the NDR region with a properly customized TIA.

Salmonella Cold Stress Response: Mechanisms and Occurrence in Foods.

Since bacteria in foods often encounter various cold environments during food processing, such as chilling, cold chain distribution, and cold storage, lower temperatures can become a major stress environment for foodborne pathogens. Bacterial responses in stressful environments have been considered in the past, but now the importance of stress responses at the molecular level is becoming recognized. Documenting how bacterial changes occur at the molecular level may help to achieve the in-depth understanding of stress responses, to predict microbial fate when they encounter cold temperatures, and to design and develop more effective strategies to control pathogens in food for ensuring food safety. Microorganisms differ in responding to a sudden downshift in temperature and this, in turn, impacts their metabolic processes and can cause various structural modifications. In this review, the fundamental aspects of bacterial cold stress responses focused on cell membrane modification, DNA supercoiling modification, transcriptional and translational responses, cold-induced protein synthesis including CspA, CsdA, NusA, DnaA, RecA, RbfA, PNPase, KsgA, SrmB, trigger factors, and initiation factors are discussed. In this context, specific Salmonella responses to cold temperature including growth, injury, and survival and their physiological and genetic responses to cold environments with a focus on cross-protection, different gene expression levels, and virulence factors will be discussed.

Laminar shear stress suppresses vascular smooth muscle cell proliferation through nitric oxide-AMPK pathway.

In healthy condition, vascular smooth muscle cells (VSMCs) are not directly exposed to shear stresses, because they are shielded by endothelial cell (EC) layer that lines blood vessels. After injury to EC layer caused by rupture of atherosclerotic lesions or invasive techniques such as angioplasty, VSMCs are directly exposed to blood flow which modulate molecular signaling and function. In endothelium, exposure to fluid shear stress has been reported to induce AMP-activated protein kinase (AMPK) phosphorylation and nitric oxide (NO) production. However, the influence of laminar shear stress on exposed VSMC is not defined. In this study, we investigated whether laminar shear stress regulates AMPK phosphorylation in VSMC and tried to identify underlying signaling pathway. NO production was increased by shear stress. The expression of NOS isoforms was increased 1 h after exposure to shear stress, and AMPK phosphorylation started to increase after 2 h. AMPK and LKB1, the upstream kinases of AMPK, phosphorylation were decreased by the non-selective NOS inhibitor l-NAME and the selective iNOS inhibitor aminoguanidine despite exposure to shear stress. On the other hand, compound C, a specific AMPK inhibitor, did not affect the expression of NOS isoforms. In addition, PDGF-induced VSMC proliferation was decreased by shear stress and restored by l-NAME. These findings suggest that shear stress upregulated AMPK phosphorylation in VSMC via NOS expression may be a beneficial route to prevent pathogenesis in the vascular system.

Development of a rapid method to quantify Salmonella Typhimurium using a combination of MPN with qPCR and a shortened time incubation.

A novel method was developed for the specific quantification of S. Typhimurium using a most-probable-number (MPN) combined with qPCR and a shortened incubation time (MPN-qPCR-SIT). For S. Typhimurium enumeration, dilutions of samples were transferred into three wells on a microtiter plate and the plate was incubated for 4 h. The S. Typhimurium presence in the wells was identified using a qPCR and populations were determined based on an MPN calculation. The R2 between the MPN-qPCR-SIT and conventional MPN exhibited a high level of correlation (0.9335-0.9752), suggesting that the MPN-qPCR-SIT offers a reliable alternative method for S. Typhimurium quantification. Although plating and qPCR were limited in their ability to detect low levels of S. Typhimurium (e.g. 0.18 log MPN/ml), these levels could be successfully detected with the MPN-qPCR-SIT. Chicken breast samples inoculated with S. Typhimurium were incubated at 0, 4, and 24 h and incubated samples were subjected to microbiome analysis. Levels of Salmonella and Enterobacteriaceae increased significantly with incubation time. The obvious benefits of the MPN-qPCR-SIT are: 1) a further confirmation step is not required, 2) the detection limit is as low as conventional MPN, but 3) is more rapid, requiring approximately 7 h to simultaneously complete quantification.

Changes in microbial composition and the prevalence of foodborne pathogens in crab marinated in soy sauce produced by six manufacturing plants.

BACKGROUND: The present study examined the changes in microbiological composition during the production process of crab marinated in soy sauce, potential microbial hazards, potential contamination routes and effective critical control points. Crab and soy sauce samples were obtained from six different manufacturing plants at different stages, and their microbiological content was comprehensively assessed by quantitative and qualitative analyses. RESULTS: The results revealed the following: (1) the final products contained 4.0 log colony-forming units (CFU) g-1 aerobic plate counts (APCs) and 1.1 log CFU g-1 coliforms, which may have been introduced from the raw materials (the level of APCs in raw crab and soy sauce mixed with other ingredients was 3.8 log CFU g-1 and 4.0 log CFU mL-1 respectively); (2) marination of crab in soy sauce may allow cross-contamination by coliforms; (3) only Bacillus cereus and Staphylococcus aureus were qualitatively detected in samples at different stages of manufacture (detection rate of 28 and 5.6% respectively), and these bacteria may impact the microbiological quality and safety of crab marinated in soy sauce; and (4) bacterial counts were either maintained or increased during the manufacturing process (suggesting that no particular step can be targeted to reduce bacterial counts). CONCLUSION: Proper management of raw materials and the marination process are effective critical control points, and alternative interventions may be needed to control bacterial quantity. The results provide important basic information about the production of crab marinated in soy sauce and may facilitate effective implementation of sanitary management practices in related industries and research fields. © 2016 Society of Chemical Industry.

Sodium bisulfate and a sodium bisulfate/tannin mixture decreases pH when added to an in vitro incubated poultry cecal or fecal contents while reducing Salmonella Typhimurium marker strain survival and altering the microbiome.

The objective of the present study was to investigate the ability of animal feed-grade sodium bisulfate (SBS) and a mixture of sodium bisulfate/tannin to inhibit the growth of Salmonella using an anerobic in vitro mixed cecal culture to mimic the conditions within the chicken cecum. An initial inoculum of Salmonella Typhimurium was introduced to an anerobic dilution solution containing 1/3000 diluted cecal bacteria and solids consisting of ground chicken feed and different percentages of solid SBS or SBS/tannin, and surviving organisms were enumerated. Two different experimental designs were employed. In the "unadapted" treatment, the S. Typhimurium was added at the beginning of the culture incubation along with cecal bacteria and chicken feed/SBS or chicken feed/SBS/tannin. In the "adapted" treatment, S. Typhimurium was added after a 24 hour pre-incubation of the cecal bacteria with the chicken feed/SBS or chicken feed/SBS/tannin. Adding SBS resulted in reduction of pH in the cultures which paralleled with the reduction of S. Typhimurium. The SBS alone was found to be inhibitory to S. Typhimurium in the adapted treatment at all concentrations tested (0.25, 0.5, and 0.75%), and the degree of inhibition was concentration-dependent. Salmonella Typhimurium was completely killed in the adapted culture with 0.5% SBS after 24 and 48 h. The SBS/tannin mixture was less inhibitory than SBS alone at the same concentrations in side-by-side comparisons. Testing at a 0.5% SBS concentration, chicken age had little or no effect on log reduction of S. Typhimurium relative to age-matched control cultures without SBS, but age did affect the absolute number of S. Typhimurium surviving, with the greatest decreases occurring at 2 and 4 weeks of age (approx. 103 S. Typhimurium surviving) compared to 6 weeks of age (approx. 105 Salmonella surviving). Microbiome analysis with an Illumina MiSeq platform was conducted to investigate bacterial compositional changes related to the addition of SBS. The relative abundance of Firmicutes (at the phylum level) was decreased, and genera Lactobacillus and Faecalibacterium were increased when SBS was added to the anaerobic mixed culture containing either fecal or cecal material. The antimicrobial action of feed-grade SBS may represent a potential pre-harvest control measure for Salmonella in poultry production.

Solution single-vesicle assay reveals PIP2-mediated sequential actions of synaptotagmin-1 on SNAREs.

Synaptotagmin-1 (Syt1) is a major Ca(2+) sensor for synchronous neurotransmitter release, which requires vesicle fusion mediated by SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors). Syt1 utilizes its diverse interactions with target membrane (t-) SNARE, SNAREpin, and phospholipids, to regulate vesicle fusion. To dissect the functions of Syt1, we apply a single-molecule technique, alternating-laser excitation (ALEX), which is capable of sorting out subpopulations of fusion intermediates and measuring their kinetics in solution. The results show that Syt1 undergoes at least three distinct steps prior to lipid mixing. First, without Ca(2+), Syt1 mediates vesicle docking by directly binding to t-SNARE/phosphatidylinositol 4,5-biphosphate (PIP(2)) complex and increases the docking rate by 10(3) times. Second, synaptobrevin-2 binding to t-SNARE displaces Syt1 from SNAREpin. Third, with Ca(2+), Syt1 rebinds to SNAREpin, which again requires PIP(2). Thus without Ca(2+), Syt1 may bring vesicles to the plasma membrane in proximity via binding to t-SNARE/PIP(2) to help SNAREpin formation and then, upon Ca(2+) influx, it may rebind to SNAREpin, which may trigger synchronous fusion. The results show that ALEX is a powerful method to dissect multiple kinetic steps in the vesicle fusion pathway.

Estrogenic compound attenuates angiotensin II-induced vascular smooth muscle cell proliferation through interaction between LKB1 and estrogen receptor α.

The prevalence rate of cardiovascular disease is higher for males than females, and estradiol (E2) induces AMP-activated protein kinase (AMPK) activation, which is known to regulate proliferation of VSMC. We identified the estrogenic properties of nordihydroguaiaretic acid (NDGA, a lignan phytoestrogen) that inhibit VSMC proliferation and explored the underlying mechanisms. Both the phosphorylation and expression of LKB1 were increased by NDGA. In addition, NDGA significantly attenuated angiotensin II (Ang II)-induced VSMC proliferation. To elucidate the estrogenic effects, we confirmed that NDGA increased estrogen receptor α (ERα) expression, similar to treatment with E2 and estriol (E3). Furthermore, tamoxifen and ERα siRNA obstructed the effects of NDGA including ERα expression, AMPK phosphorylation and both LKB1 phosphorylation and expression. VSMC proliferation was restored by tamoxifen and ERα siRNA. LKB1 siRNA also reversed the NDGA-mediated inhibition of VSMC proliferation. The estrogenic activity of NDGA induced LKB1 translocation from nucleus to cytosol, and tamoxifen obstructed LKB1 translocation. The absence of LKB1 completely abolished the increase of ERα expression induced by NDGA. Taken together, the beneficial effects of estrogenic compound (E2 and NDGA) on inhibition of VSMC proliferation are mediated by interaction between LKB1 and ERα, suggesting a potential mechanism for females having less cardiovascular disease.

Comparison of methods for quantitating Salmonella enterica Typhimurium and Heidelberg strain attachment to reusable plastic shipping container coupons and preliminary assessment of sanitizer efficacy.

Salmonella serovars, one of the leading contributors to foodborne illness and are especially problematic for foods that are not cooked before consumption, such as fresh produce. The shipping containers that are used to transport and store fresh produce may play a role in cross contamination and subsequent illnesses. However, methods for quantitatively attached cells are somewhat variable. The overall goal of this study was to compare conventional plating with molecular methods for quantitating attached representative strains for Salmonella Typhimurium and Heidelberg on reusable plastic containers (RPC) coupons, respectively. We attached Salmonella enterica serovar Typhimurium ATCC 14028 and serovar Heidelberg SL486 (parent and an antibiotic resistant marker strain) to plastic coupons (2.54 cm(2)) derived from previously used shipping containers by growing for 72 h in tryptic soy broth. The impact of the concentration of sanitizer on log reductions between unsanitized and sanitized coupons was evaluated by exposing attached S. Typhimurium cells to 200 ppm and 200,000 ppm sodium hypochlorite (NaClO). Differences in sanitizer effectiveness between serovars were also evaluated with attached S. Typhimurium compared to attached S. Heidelberg populations after being exposed to 200 ppm peracetic acid (PAA). Treatment with NaClO caused an average of 2.73 ± 0.23 log CFU of S. Typhimurium per coupon removed with treatment at 200 ppm while 3.36 ± 0.54 log CFU were removed at 200,000 ppm. Treatment with PAA caused an average of 2.62 ± 0.15 log CFU removed for S. Typhimurium and 1.41 ± 0.17 log CFU for S. Heidelberg (parent) and 1.61 ± 0.08 log CFU (marker). Lastly, scanning electron microscopy (SEM) was used to visualize cell attachment and coupon surface topography. SEM images showed that remaining attached cell populations were visible even after sanitizer application. Conventional plating and qPCR yielded similar levels of enumerated bacterial populations indicating a high concordance between the two methods. Therefore, qPCR could be used for the rapid quantification of Salmonella attached on RPC.

Silicon photonic receiver and transmitter operating up to 36 Gb/s for λ~1550 nm.

We present the hybrid-integrated silicon photonic receiver and transmitter based on silicon photonic devices and 65 nm bulk CMOS interface circuits operating over 30 Gb/s with a 10(-12) bit error rate (BER) for λ ~1550nm. The silicon photonic receiver, operating up to 36 Gb/s, is based on a vertical-illumination type Ge-on-Si photodetector (Ge PD) hybrid-integrated with a CMOS receiver front-end circuit (CMOS Rx IC), and exhibits high sensitivities of -11 dBm, -8 dBm, and -2 dBm for data rates of 25 Gb/s, 30 Gb/s and 36 Gb/s, respectively, at a BER of 10(-12). The measured energy efficiency of the Si-photonic receiver is 2.6 pJ/bit at 25 Gb/s with an optical input power of -11 dBm, and 2.1 pJ/bit at 36 Gb/s with an optical power of -2 dBm. The hybrid-integrated silicon photonic transmitter, comprised of a depletion-type Mach-Zehnder modulator (MZM) and a CMOS driver circuit (CMOS Tx IC), shows better than 5.7 dB extinction ratio (ER) for 25 Gb/s, and 3 dB ER for 36 Gb/s. The silicon photonic transmitter achieves the data transmission with less than 10(-15) BER at 25 Gb/s, 10(-14) BER at 28 Gb/s, and 6 x 10(-13) BER with the energy efficiency of ~6 pJ/bit at 30 Gb/s.

SOX4 expression is associated with treatment failure and chemoradioresistance in oral squamous cell carcinoma.

BACKGROUND: In humans, sex-determining region-Y (SRY) related high-mobility-group box 4 (SOX4) is linked to development and tumorigenesis. SOX4 is over-expressed in several cancers and has prognostic significance. This study evaluated whether SOX4 affects oncogenic behavior and chemoradiotherapy response in head and neck squamous cell carcinoma (HNSCC) cells, and documented the relationship between its expression and prognosis in oral squamous cell carcinoma (OSCC). METHODS: We used small interfering RNA in HNSCC cells to evaluate the effect of SOX4 on cell proliferation, apoptosis, chemoradiation-induced apoptosis, invasion, and migration. SOX4 expression in OSCC tissues was investigated by immunohistochemistry. RESULTS: SOX4 knockdown (KO) decreased cell proliferation and induced apoptosis by activating caspases-3 and -7, and poly-ADP ribose polymerase and suppressing X-linked inhibitor of apoptosis protein in HNSCC cells; it also enhanced radiation/cisplatin-induced apoptosis; and suppressed tumor cell invasion and migration. Immunostaining showed SOX4 protein was significantly increased in OSCC tissues compared with adjacent normal mucosa. SOX4 expression was observed in 51.8 % of 85 OSCC tissues, and was significantly correlated with treatment failure (P = 0.032) and shorter overall survival (P = 0.036) in patients with OSCC. CONCLUSIONS: SOX4 may contribute to oncogenic phenotypes of HNSCC cells by promoting cell survival and causing chemoradioresistance. It could be a potential prognostic marker for OSCC.

Mediating role of critical thinking disposition in the relationship between perceived barriers to research use and evidence-based practice.

BACKGROUND: Despite the importance of critical thinking in clinical and educational settings, little is known about its role in evidence-based practice (EBP). AIM: This study examined whether critical thinking disposition (CTD) mediates the relationship between perceived barriers to research use and EBP in clinical nurses (N=409). METHODS/DESIGN: A path diagram using structural equation modeling was used to estimate the direct and indirect effects of perceived barriers to research use on EBP, controlling for CTD as a mediator. RESULTS: CTD partially mediated the relationship between perceived barriers to research use and EBP. Furthermore, the hypothesized mediation model demonstrated an appropriate fit to the data. CONCLUSIONS: Individual and organizational efforts are needed to help nurses further improve their critical thinking skills. CTD is important as research barriers to engage effectively in EBP. Without the skills to evaluate evidence carefully, research utilization may be compromised.

Compact-sized high-modulation-efficiency silicon Mach-Zehnder modulator based on a vertically dipped depletion junction phase shifter for chip-level integration.

We present small-sized depletion-type silicon Mach-Zehnder (MZ) modulator with a vertically dipped PN depletion junction (VDJ) phase shifter based on a CMOS compatible process. The fabricated device with a 100 µm long VDJ phase shifter shows a VπLπ of ∼0.6 V·cm with a 3 dB bandwidth of ∼50 GHz at -2 V bias. The measured extinction ratios are 6 and 5.3 dB for 40 and 50 Gb/s operation under 2.5 Vpp differential drive, respectively. On-chip insertion loss is 3 dB for the maximum optical transmission. This includes the phase-shifter loss of 1.88 dB/100 µm, resulting mostly from the extra optical propagation loss through the polysilicon-plug structure for electrical contact, which can be readily minimized by utilizing finer-scaled lithography nodes. The experimental result indicates that a compact depletion-type MZ modulator based on the VDJ scheme can be a potential candidate for future chip-level integration.

Microbial dynamics of South Korean beef and surroundings along the supply chain based on high-throughput sequencing.

Microbiological safety and quality of beef is crucial as beef can serve as a reservoir for a variety of bacteria, including spoilage-related and foodborne pathogens. Controlling microbial contamination is a critical aspect of food quality and safety, but it is difficult to prevent as there are several potential sources of contamination from production to distribution. In this study, the microbiological ecology of cattle/beef and associated environmental samples (n = 69) were trace-investigated to reveal microbiome shifts in cattle/beef and possible cross-contaminants throughout the entire supply chain using 16S rRNA gene sequencing. Pseudomonas, Psychrobacter, and Acinetobacter, known as spoilage bacteria, opportunistic pathogens, or antibiotic-resistant bacteria, were the main microorganisms present in cattle/beef, and Staphylococcus became abundant in the final products. The dominance of Acinetobacter and Pseudomonas was noticeable in the slaughtered carcasses and slaughterhouse environment, indicating that the slaughterhouse is a critical site where hygienic practices are required to prevent further contamination. Taxonomic similarities between cattle/beef and several environmental samples, as well as diversity analysis, presented a high potential for microbial transmission. Source tracking identified environmental samples that primarily contributed to the microbiota of cattle/beef. Farm floor (48%), workers' gloves (73%), and carcass splitters (20%) in the slaughterhouse were found to be major sources influencing the microbiome of cattle/beef at the farm, slaughterhouse, and processing plant, respectively. These findings demonstrated the dynamics of bacterial communities in cattle/beef according to stage and detected potential contamination sources, which may aid in a better understanding and control of microbial transmission in beef production.

Bacterial profile of pork from production to retail based on high-throughput sequencing.

Pork is a common vehicle for foodborne pathogens, including Salmonella spp. and Yersinia enterocolitica. Cross-contamination can occur at any stage of the pork production chain, from farm to market. In the present study, high-throughput sequencing was used to characterize bacterial profiles and track their changes along the whole supply chain. Tracked meat samples (pig on the farm, carcass in the slaughterhouse, unprocessed carcass and processed meat in the processing plant, and fresh pork at the local retail stores) and their associated environmental samples (e.g., water, floor, feed, feces, and workers' gloves) were collected from sequential stages (n = 96) and subjected to 16S rRNA metataxonomic analyses. At the farm, a total of 652 genera and 146 exclusive genera were identified in animal and environmental samples (pig, drain, floor, fan, and feces). Based on beta diversity analysis, it was demonstrated that the microbial composition of animal samples collected at the same processing step is similar to that of environmental samples (e.g., drain, fan, feces, feed, floor, gloves, knives, tables, and water). All animal and environmental samples from the slaughterhouse were dominated by Acinetobacter (55.37 %). At the processing plant, belly meat and neck meat samples were dominated by Psychrobacter (55.49 %). At the retail level, key bacterial players, which are potential problematic bacteria and important members with a high relative abundance in the samples, included Acinetobacter (8.13 %), Pseudomonas (6.27 %), and Staphylococcus (2.13 %). In addition, the number of confirmed genera varied by more than twice that identified in the processing plant. Source tracking was performed to identify bacterial contamination routes in pork processing. Animal samples, including the processing plant's carcass, the pig from the farm, and the unwashed carcass from the slaughterhouse (77.45 %), along with the processing plant's gloves (5.71 %), were the primary bacterial sources in the final product. The present study provides in-depth knowledge about the bacterial players and contamination points within the pork production chain. Effective control measures are needed to control pathogens and major pollutants at each stage of pork production to improve food safety.