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In the industry 4.0, the Cyber-physical system (CPS) is one of the most important core which makes the manufacturing process more intelligent. Intelligent assembly operation is an important key in intelligent manufacturing of CPS. To complete the intelligent assembly operation, the cooperation between assembly robotic arm and assembly sequence planning (ASP) is necessary. However, the ASP and writing robotic codes manually is time consuming and requires professional knowledge and experience. Because the Local Coordinate System (LCS) is often ignored when checking for interference. If product have inclined interference and without considering LCS and causing and infeasible ASP. Therefore, this paper proposes a LCCPIAS (Local Coordinate Cyber-Physical Intelligent Assembly System) system to achieve three objective functions. First, this paper presents a dual-projected-based interference analysis approach (DPIAA) that analyzes the relations between components. Second, this paper generates optimal assembly sequence automatically to let the assembly sequence more suitable for the robotic arm to perform the assembly operation. The last one is LCS can recognize inclined interference between components and generate feasible ASP. Furthermore, this paper uses CAD model to verify that the DPIAA is faster and consider LCS interference can solve inclined interference problem. In the future assembly factory, the proposed method can help to realize intelligent manufacturing.

This article discusses an unusual case of mesenteric fibromatosis in a 35-year-old male patient. The patient presented with symptoms of abdominal fullness, pain, and vomiting, and a CT scan revealed a mesenteric soft tissue mass. During surgery, the mass was successfully removed along with a segment of the jejunum and transverse colon. Microscopic examination and immunohistochemistry confirmed the diagnosis of mesenteric fibromatosis. The article provides information on the characteristics, diagnosis, and treatment options for this rare tumor. [Extracted from the article]

In this study, we integrated genetic detection for polymerase chain reaction (PCR) with microfluidics technology for the detection of peanut DNA. A cross-junction microchannel was used to induce emulsion droplets of water in oil for PCR on a chip. Compared with the single-phase flow, the emulsion droplet flow exhibited a 7.24% lower evaporation amount and prevented air bubble generation. PCR results of the droplet microfluidic PCR chip for peanut DNA fragment detection was verified by comparison with a commercial PCR thermal cycler and increased fluorescence intensity in SYBR Green reagent-based PCR. Moreover, PCR on the microfluidic PCR chip was successful for sesame, Salmonella spp., and Staphylococcus aureus. The droplet microfluidic PCR device developed in this study can be applied for peanut detection in the context of food allergy. [ABSTRACT FROM AUTHOR]

Abstract: A class of neutral tris‐bidentate IrIII metal complexes incorporating a diphosphine as a chelate is prepared and characterized here for the first time. Treatment of [Ir(dppBz)(tht)Cl3] (1, dppBz=1,2‐bis(diphenylphosphino)benzene, tht=tetrahydrothiophene) with fppzH (3‐trifluoromethyl‐5‐(2′‐pyridyl)‐1H‐pyrazole) afforded the dichloride complexes, trans‐(Cl,Cl)[Ir(dppBz)(fppz)Cl2] (2) and cis‐(Cl,Cl)[Ir(dppBz)(fppz)Cl2] (3). The reaction of 3 with the dianionic chelate precursor, 5,5′‐di(trifluoromethyl)‐3,3′‐bipyrazole (bipzH2) or 5,5′‐(1‐methylethylidene)‐bis(3‐trifluoromethyl‐1H‐pyrazole) (mepzH2), in DMF gave the tris‐bidentate complex [Ir(dppBz)(fppz)(bipz)] (4) or [Ir(dppBz)(fppz)(mepz)] (5), respectively. In contrast, a hydride complex [Ir(dppBz)(fppz)(bipzH)H] (6) was isolated instead of 4 in protic solvent, namely: diethylene glycol monomethyl ether (DGME). All complexes 2–6 are luminescent in powder form and thin films where the dichlorides (2, 3) emit with maxima at 590–627 nm (orange) and quantum yields (QYs) up to 90 % whereas the tris‐bidentate (4, 5) and hydride (6) complexes emit at 455–458 nm (blue) with QYs up to 70 %. Hybrid (time‐dependent) DFT calculations showed considerable metal‐to‐ligand charge transfer contribution to the orange‐emitting 2 and 3 but substantial ligand‐centered 3π–π* transition character in the blue‐emitting 4–6. The dppBz does not participate in the radiative transitions in 4–6, but it provides the rigidity and steric bulk needed to promote the luminescence by suppressing the self‐quenching in the solid state. Fabrication of an organic light‐emitting diode (OLED) with dopant 5 gave a deep‐blue CIE chromaticity of (0.16, 0.15). Superior blue emitters, which are vital in OLED applications, may be found in other neutral IrIII complexes containing phosphine chelates. [ABSTRACT FROM AUTHOR]

Bis-tridentate Ir(III) metal complexes are expected to show great potential in organic light-emitting diode (OLED) applications due to the anticipated, superb chemical and photochemical stability. Unfortunately, their exploitation has long been hampered by lack of adequate methodology and with inferior synthetic yields. This hurdle can be overcome by design of the first homoleptic, bis-tridentate Ir(III) complex [Ir(pzpyph)(pzHpyph)] ( 1), for which the abbreviation (pzpyph)H (or pzHpyph) stands for the parent 2-pyrazolyl-6-phenyl pyridine chelate. After that, methylation and double methylation of 1 afford the charge-neutral Ir(III) complex [Ir(pzpyph)(pzMepyph)] ( 2) and cationic complex [Ir(pzMepyph)2][PF6] ( 3), while deprotonation of 1 gives formation of anionic [Ir(pzpyph)2][NBu4] ( 4), all in high yields. These bis-tridentate Ir(III) complexes 2- 4 are highly emitted in solution and solid states, while the charge-neutral 2 and corresponding t-butyl substituted derivative [Ir(pzpyBuph)(pzMepyBuph)] ( 5) exhibit superior photostability versus the tris-bidentate references [Ir(ppy)2(acac)] and [Ir(ppy)3] in toluene under argon, making them ideal OLED emitters. For the track record, phosphor 5 gives very small efficiency roll-off and excellent overall efficiencies of 20.7%, 66.8 cd A−1, and 52.8 lm W−1 at high brightness of 1000 cd m−2. These results are expected to inspire further studies on the bis-tridentate Ir(III) complexes, which are judged to be more stable than their tris-bidentate counterparts from the entropic point of view. [ABSTRACT FROM AUTHOR]

Surfaces with gold dendritic nanoforests (Au DNFs) on Si chips demonstrate broadband-light absorption. This study is the first to utilize localized surface plasmons of Au DNFs/Si chips for polymerase chain reaction (PCR) applications. A convenient halogen lamp was used as the heating source to illuminate the Au DNFs/Si chip for PCR. A detection target of Salmonella spp. DNA fragments was reproduced in this plasmonic PCR chip system. By semi-quantitation in gel electrophoresis analysis, the plasmonic PCR with 30 cycles and a largely reduced processing time provided results comparable with those of a commercial PCR thermal cycler with 40 cycles in more than 1 h. In the presence of an Au DNFs/Si chip, the plasmonic PCR provides superior results in a short processing time. [ABSTRACT FROM AUTHOR]

A class of neutral tris-bidentate Ir III metal complexes incorporating a diphosphine as a chelate is prepared and characterized here for the first time. Treatment of [Ir(dppBz)(tht)Cl 3 ] (1, dppBz=1,2-bis(diphenylphosphino)benzene, tht=tetrahydrothiophene) with fppzH (3-trifluoromethyl-5-(2'-pyridyl)-1H-pyrazole) afforded the dichloride complexes, trans-(Cl,Cl)[Ir(dppBz)(fppz)Cl 2 ] (2) and cis-(Cl,Cl)[Ir(dppBz)(fppz)Cl 2 ] (3). The reaction of 3 with the dianionic chelate precursor, 5,5'-di(trifluoromethyl)-3,3'-bipyrazole (bipzH 2 ) or 5,5'-(1-methylethylidene)-bis(3-trifluoromethyl-1H-pyrazole) (mepzH 2 ), in DMF gave the tris-bidentate complex [Ir(dppBz)(fppz)(bipz)] (4) or [Ir(dppBz)(fppz)(mepz)] (5), respectively. In contrast, a hydride complex [Ir(dppBz)(fppz)(bipzH)H] (6) was isolated instead of 4 in protic solvent, namely: diethylene glycol monomethyl ether (DGME). All complexes 2-6 are luminescent in powder form and thin films where the dichlorides (2, 3) emit with maxima at 590-627 nm (orange) and quantum yields (QYs) up to 90 % whereas the tris-bidentate (4, 5) and hydride (6) complexes emit at 455-458 nm (blue) with QYs up to 70 %. Hybrid (time-dependent) DFT calculations showed considerable metal-to-ligand charge transfer contribution to the orange-emitting 2 and 3 but substantial ligand-centered 3 π-π* transition character in the blue-emitting 4-6. The dppBz does not participate in the radiative transitions in 4-6, but it provides the rigidity and steric bulk needed to promote the luminescence by suppressing the self-quenching in the solid state. Fabrication of an organic light-emitting diode (OLED) with dopant 5 gave a deep-blue CIE chromaticity of (0.16, 0.15). Superior blue emitters, which are vital in OLED applications, may be found in other neutral Ir III complexes containing phosphine chelates., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Despite the fast boom of thermally activated delayed fluorescence (TADF) emitters bearing borane-based acceptor, so far, no TADF emitter with a direct B-N linkage between N-donor and boryl acceptor has been reported. The latter should simplify the molecular architecture and hence facilitate the synthetic design and versatility. We report here the preparation and characterization of a new series of N-borylated compounds with functional acridine donor unit; namely: ACBM, PACBM, and SACBM. Spectroscopic studies were performed to explore their photophysical properties that exhibited prominent solvatochromism and thermally activated delayed fluorescence. The time-dependent DFT calculation indicated the involvement of substantial intramolecular charge transfer character for which HOMO and LUMO are spatially separated. For compound SACBM, fabrication of green emitting OLED gave CIE chromaticity of (0.22, 0.59) and maximum external quantum efficiency, luminance efficiency and power efficiency of 19.1%, 60.9 cd/A, and 43.6 lm/W, respectively, demonstrating for the first time the highly efficient OLEDs using N-borylated TADF emitters.

Staphylococcus aureus is one of the major bacterial species that may cause clinical infection and food-poisoning cases. Strains of this species may produce a series of superantigens (SAgs). Due to the importance of staphylococcal infections, reliable methods for the discrimination of strains of this species are important. Such data may allow us to trace the infection origins and be used for epidemiological study. For strain discrimination, genotyping methods, such as pulsed-field gel electrophoresis (PFGE), random amplified polymorphic DNA (RAPD), and multi-locus sequence typing (MLST), etc., could be used. Recently, toxin gene profiles, which can be used for the elucidation of the genetic and pathogenic relatedness between strains, also have been used to improve the strain discrimination. For S. aureus, as more SAg genes were discovered, the SAg profiles become more useful for the strain discrimination of S. aureus. In this chapter, a method for the discrimination of S. aureus strains using superantigen profiles will be described in detail.

Staphylococcus aureus is one of the major bacterial species that may cause clinical infection and food-poisoning cases. Strains of this bacterial species may produce a series of superantigens (SAgs) (i.e., staphylococcal enterotoxins [SEs], staphylococcal enterotoxin-like toxins, and toxic shock syndrome toxin). In this study, S. aureus strains from clinical samples and food-poisoning cases in Taiwan were collected; their SAg profiles, and SmaI digestion patterns determined by pulsed-field gel electrophoresis (PFGE), were then analyzed. Results showed that their SAg gene profiles and SmaI digestion patterns of chromosomal DNA were highly diverse. Although PFGE has been used as a criterion standard for typing of S. aureus strains, and the SAg profiles have been used in combination with PFGE for typing of S. aureus strains, we found that strains grouped in these combined patterns could be further discriminated by the random amplified polymorphic DNA (RAPD) method. Thus, the combined use of SAg profiles, PFGE, and RAPD patterns permits high discrimination for typing of S. aureus strains from not only the clinical samples but also the food-poisoning cases. Such a combined method may be used as a highly accurate approach for epidemiological study and tracing of the contamination origin of staphylococcal infections either in hospitals or food-poisoning cases.

Consumption of Salmonella-contaminated foods, such as poultry and fresh eggs, is known to be one of the main causes of salmonellosis. Conventional PCR methods, including real-time PCR for rapid detection of Salmonella, in general require skilled technicians and costly instruments. A recently developed novel convective PCR, insulated isothermal PCR (iiPCR), is carried out in polycarbonate capillary tubes. In this study, we designed TaqMan probes and PCR primers based on the yrfH gene encoding a heat shock protein for the iiPCR detection of Salmonella in chicken meat samples. The TaqMan probe was labeled with 6-carboxyfluorescein and 6-carboxytetramethylrhodamine at the 5' and 3' ends, respectively. The PCR amplicon was 133 bp. A typical run of this iiPCR assay was completed within 1 h. Specific PCR products were obtained for 148 strains representing 49 serotypes of Salmonella tested. Under the same conditions, false-positive results were not obtained for 98 non-Salmonella strains tested, including strains of Enterobacteriaceae closely related to Salmonella. For chicken meat samples, with a 5-h enrichment step Salmonella at as low as 10⁰ CFU/g of poultry meat could be detected. Because the amplification signals from the probes are detectable at 520 nm, identification of the PCR products by gel electrophoresis is not required. Compared with conventional PCR, the iiPCR system requires less expertise and provides an economical, reliable, and rapid tool for result interpretation. Detection results can be obtained within 8 h, including the enrichment and DNA extraction steps.

Staphylococcus spp., including S. aureus, S. intermedius, S. hyicus, S. epidermidis, S. saprophyticus, S. haemolyticus, S. xylosus, and S. carnosus, are major bacterial species associated with food poisoning, and human and veterinary clinics. Traditional methods for the identification of these staphylococci are time-consuming, laborious, or inaccurate. Therefore, rapid and accurate diagnostic methods are needed. In this study, we designed the DNA probes and polymerase chain reaction (PCR) primers for the detection of the aforementioned Staphylococcus species. These primers were proved to be specific for the detection of their corresponding target strains. Furthermore, by using a consensus primer pair, we were able to co-amplify the intergenic region of groES-groEL for these staphylococci. Followed by a chromogenic macroarray system with the specific probes on the plastic chips, these staphylococci in milk products or clinical samples could be simultaneously detected. When the system was used for the inspection of milk or urine samples containing N × 10⁰ target cells per milliliter of the sample, all these staphylococcal species could be identified after an 8-h pre-enrichment step. This system also allowed the adequate diagnosis of bacteremia, since N × 10⁰ target cells per milliliter of the blood samples could be detected after a 12-h pre-enrichment. Compared to the multiplex PCR method, this approach has the additional advantage that it allowed the discrimination of more bacterial strains-even some bacterial strains that may generate PCR products with the same molecular sizes.

Due to the increasing use of bifidobacteria in probiotic products, it is essential to establish a rapid method for the qualitative and quantitative assay of the bifidobacteria in commercial products. In this study, partial sequences of the tuf gene for 18 Bifidobacterium strains belonging to 14 species were determined. Alignment of these sequences showed that the similarities among these Bifidobacterium species were 82.24% to 99.72%. Based on these tuf gene sequences, 6 primer sets were designed for the polymerase chain reaction (PCR) assay of B. animalis subsp. animalis, B. animalis subsp. lactis, B. bifidum, B. breve, B. longum subsp. infantis, B. longum subsp. longum, and the genus of Bifidobacterium, respectively. These Bifidobacterium species are common probiotic species present in dairy and probiotic products. When each target Bifidobacterium spp. was assayed with the designed primers, PCR product with expected size was generated. In addition, for each target species, more than 70 bacterial strains other than the target species, including strains of other Bifidobacterium species, strains of Lactobacillus spp., Enterococcus spp., and other bacterial species, all generated negative results. PCR assay with primers specific to B. animalis subsp. lactis and B. longum subsp. longum confirmed the presence of these Bifidobacterium species in commercial yogurt products. In addition, for each product, enumeration of the bifidobacteria cells by culture method with BIM-25 agar and the quantitative real-time PCR showed similar cell counts. Such results indicated that within 15-d storage (4 °C) after manufacture, all the bifidobacteria cells originally present in yogurt products were viable and culturable during the storage.

Abstract Staphylococcus aureus is one of the major pathogens that can cause staphylococcal infection and food poisoning. There are five major classical types of staphylococcal enterotoxins (SEs): SEA, SEB, SEC, SED, and SEE, as well as new SEs or SE-like superantigens (SAgs), such as SEG to SEU. Since many S. aureus strains harbor more than one SE gene and identification of SEs involved in food poisoning cases is time consuming, we developed a chromogenic macroarray method that allows convenient and simultaneous detection of classical SE genes and a new SE gene (seg), which is phylogenetically highly related to seb and sec. Two sets of degenerated primers labeled with biotin were used to co-amplify all SE genes in S. aureus strains through the polymerase chain reaction (PCR). Afterwards, these biotin-labeled PCR products were hybridized with SE gene-specific probes spotted on the nitrocellulose membrane. When this macroarray was used to detect enterotoxingenic S. aureus in milk or beef homogenate containing 10(0)-10(4) target cells per milliliter or gram of the sample, all six enterotoxin genes could be identified after a 12-hour enrichment step. This macroarray offers clinical and food inspection laboratories a rapid and economical visual method to detect common enterotoxigenic S. aureus strains.

PCR primers specific for the detection of Lactobacillus acidophilus, Lactobacillus casei group, Lactobacillus delbrueckii, and Bifidobacterium longum were designed based on the elongation factor Tu gene (tuf). The specificity of these four primer sets were confirmed by PCR with 88 bacterial strains of Lactobacillus, Enterococcus, Bifidobacterium, and other bacterial species. Results indicated that these primer sets generated predicted PCR products of 397, 230, 202, and 161 bp for L. acidophilus, L. delbrueckii, L. casei group, and B. longum, respectively. Bacterial species other than the target organisms tested did not generate false-positive results. When these four primer sets were combined for the simultaneous detection of the lactic acid bacteria (LAB) in fermented milk products including yogurt, the LAB species listed on the labels of these products could be identified without the preenrichment step. The identification limit for each LAB strain with this multiplex PCR method was N X 10(3) CFU/ml in milk samples. The results of our multiplex PCR method were confirmed by PCR assay using primers based on the 16S rDNA or the 16S-23S intergenic spacer region and by biochemical tests using the API 50 CHL kit. When this multiplex PCR method was used with the determination of counts of total viable LAB and bifidobacteria, the quality of commercial fermented milk products could be assured.

Staphylococcus aureus may cause foodborne disease outbreaks and staphylococcal infections and is one of the major causes of mastitis. Rapid and reliable methods for detection of this microorganism in milk and other foods are needed. In this study, we designed a primer set from the sequence of the heat shock protein gene htrA, a gene coding for high-temperature-requirement A (HtrA) protein, and used it for real-time PCR detection of S. aureus isolates: 16 reference strains and 40 strains isolated from food-poisoning cases. All strains tested generated positive results. Bacterial strains other than S. aureus, including strains of other Staphylococcus species, did not produce positive results. When this primer set was used for the real-time PCR detection of S. aureus in milk and meat samples without the preenrichment step, samples with target cell numbers greater than 10(3) CFU/ml or CFU/g could be detected, indicating the potential quantitative ability of this real-time PCR assay. With a 10-h preenrichment step, however, a detection limit of 1 CFU/ml or CFU/g could be obtained.

Staphylococcal enterotoxins (SEs) are important causative agents in gastroenteritidis and food poisoning cases. They are serologically grouped into five major classical types, i.e., SEA, SEB, SEC, SED, and SEE. In addition, new SEs, such as SEG through SEM, have recently been identified and characterized. In an attempt to survey the distribution of classical and new SEs in organisms responsible for staphylococcal infections in Taiwan, we developed PCR primers for the genes that define the SEK, SEL, and SEM types. Bacterial strains other than sek, sel, and sem Staphylococcus aureus, including strains of other Staphylococcus species, did not generate any false-positive results when examined with these primers. The expression potential for the sek, sel, and sem types were also determined by reverse transcription-PCR. Together with the PCR primers specific for the classical SEs and other new SEs, including SEG, SEH, SEI, and SEJ, we surveyed the SE genes in S. aureus strains isolated from food poisoning cases. For 147 S. aureus isolates originating from food poisoning cases, 109 (74.1%) were positive for one or more SE genes. Of them, the major classical enterotoxin type was sea (28.6%), followed by seb (20.4%), sec (8.2%), and sed (2.0%). For the new SE types, sei (30.6%) was detected the most often, followed by sek (18.4%), sem (12.9%), and sel (8.2%). Also, 64 (43.5%) of the total bacterial strains had more than one enterotoxin gene.