Bandwidth Tunable Optical Filter Based on the Quad-Mode Resonator

An innovative bandwidth tunable optical filter with controllable bandwidth, center frequency, and transmission zero is proposed in this paper. The proposed filter utilizes a quad-mode resonator to achieve a wideband filter centered at 2.42 GHz. By incorporating varactor diodes into the open branches of the resonator, the proposed filter's center frequency and bandwidth can be dynamically adjusted via the voltage applied to the diodes. This tunable filter exhibits low insertion loss of less than 2 dB, return loss exceeding 10 dB, and a relative bandwidth of up to 40%

A New Type of High-Efficiency and Portable Digital Electric Experiment Board

With the continuous advancement of digital electronic technology, the domestic emphasis on cultivating talents in the field of digital technology has been increasing. Our team designed an efficient and high-precision digital circuit experiment board that is small in size, easy to carry and store, and is not limited by the site. It can be used for experiments in dormitories, classrooms or training rooms. The designed digital signal generation board is easy to operate, low in error rate, flexible in structural design, and improves the stability, safety and reliability of the circuit

Phenotypic and molecular characterization of multidrug resistant Klebsiella pneumoniae isolated from a university teaching hospital, China.

The multidrug-resistant rate of Klebsiella pneumoniae has risen rapidly worldwide. To better understand the multidrug resistance situation and molecular characterization of Klebsiella pneumoniae, a total of 153 Klebsiella pneumoniae isolates were collected, and drug susceptibility test was performed to detect its susceptibility patterns to 13 kinds of antibiotics. Phenotypic tests for carbapenemases ESBLs and AmpC enzyme-producing strains were performed to detect the resistance phenotype of the isolates. Then PCR amplification and sequencing analysis were performed for the drug resistance determinants. The results showed that 63 strains harbored bla CTX-M gene, and 14 strains harbored bla DHA gene. Moreover, there were 5 strains carrying bla KPC gene, among which 4 strains carried bla CTX-M, bla DHA and bla KPC genes, and these 4 strains were also resistant to imipenem. Our data indicated that drug-resistant Klebsiella pneumoniae were highly prevalent in the hospital. Thus it is warranted that surveillance of epidemiology of those resistant isolates should be a cause for concern, and appropriate drugs should be chosen

Diagnostic utility of neutrophil CD64 as a marker for early-onset sepsis in preterm neonates.

Neutrophil CD64 has been proposed as an early marker of sepsis. This study aims to evaluate the diagnostic utility of neutrophil CD64 for identification of early-onset sepsis in preterm neonates.The prospective study was conducted in a neonatal intensive care unit between November 2010 and June 2011. Preterm neonates in whom infection was suspected when they were <12 hours of age were enrolled. Complete blood count with differential, blood culture, neutrophil CD11b and CD64 measurement were performed. Receiver operating characteristic curve analysis was performed to evaluate the performance of neutrophil CD64 as biomarker of sepsis.A total of 158 preterm neonates was enrolled, 88 of whom were suspected infection. The suspected sepsis group was of lesser gestational age (P<0.001) and lower birth weight (P<0.001), compared with controls. The hematologic profiles of the suspected sepsis group were characterized by higher white blood cell count, neutrophil counts and C-reactive protein. The suspected sepsis neonates had significantly higher neutrophil CD64 expression compared with controls. Neutrophil CD64 had an area value under the curve of 0.869 with an optimal cutoff values of 1010 phycoerythrin molecules bound/cell and it had a high sensitivity (81.82%) and negative predictive value (77.4%). The level of neutrophil CD64 was independent of antibiotic therapy within 24 hours after the onset of sepsis in preterm neonates.Neutrophil CD64 is a highly sensitive marker for suspected early-onset sepsis in preterm neonates. Our study suggests that neutrophil CD64 may be incorporated as a valuable marker to diagnose infection

Molecular authentication of the traditional Chinese medicine Tongren Dahuoluo Wan and its alternative formulation

Tongren Dahuoluo Wan has been a popular traditional Chinese medicine in international pharmaceutical markets for hundreds of years. Leopard bone powder is the key element in its formulation. However, the leopard has been listed for wildlife conservation, which limits the use of the leopard bone supplies. Therefore, an alternative formulation which substitutes leopard bone with zokor bone in the formula of Tongren Dahuoluo Wan is now manufactured. To develop a simple and reliable molecular method for authenticating the two patent medicines, mitochondrial nucleotide polymorphic sites of 12S rRNA, COI and Cytb genes were screened in leopard and zokor bones, and nine pairs of species-specific primers were verified for discriminating the two species. For the patent medicine authentication, we set up a molecular diagnostic assay to resolve the difficulties of low concentration of target DNAs and presence of PCR-inhibitory substances in this complex medicine, and successfully confirmed leopard or zokor content using the nine pairs of species-specific primers. We recommend a common technical strategy for authentication of species origins in traditional Chinese medicine, and discuss the experimental solutions for technical problems of molecular diagnostic assays

Distribution, Source Apportionment and Risk Assessment of Phthalate Esters in the Overlying Water of Baiyang Lake, China

As a kind of endocrine disruptor compounds, the presence of phthalate esters (PAEs) has become a global concern. In this study, the pollution levels and spatial distribution of sixteen PAEs were investigated. Their potential sources and eco-environmental health risk were discussed in Baiyang Lake and its upstream rivers during different periods. PAEs were detected in all of samples, ranging from 1215 to 3014 ng·L−1 in October 2020 and 1384 to 3399 ng·L−1 in May 2021. Dibutyl phthalate (DBP) and di-isobutyl phthalate (DIBP) were the predominant monomers, with a detection rate of 100% and the highest concentrations in the overlying water. Restricted by multiple factors, the spatial distribution difference between Baiyang Lake and its upstream rivers in October was more significant than in May. The source apportionment revealed that agricultural cultivation and disorderly use and disposal of plastic products were the primary factors for the contamination. The human health risk assessment indicated that eight PAE congeners did not pose significant carcinogenic and non-carcinogenic harms to males, females and children. However, the ecological risks of DBP, DIBP and di (2-ethylhexyl) phthalate to algae, crustaceans and fish species were moderate or high-risk levels. This study provides an appropriate dataset for the assessment of the pollution of PEs to the water ecosystem affected by anthropogenic activities

Clinical characteristics of the study groups.

<p>Clinical characteristics of the study groups.</p

Boxplot distribution of the nCD64 in suspected group and control group.

<p>The <i>box</i> shows the 25^th–75^th percentiles, whereas the <i>whiskers</i> indicate the 10^th and 90^th percentiles. T1, time at onset of sepsis (<12 hours after birth); T2, 12 hour after the onset of sepsis; T3, 72 hour after the onset of sepsis.</p