Problem-Centered Supplemental Instruction in Biology: Influence on Content Recall,Content Understanding,and Problem Solving Ability

To address the need for effective, efficient ways to apply active learning in undergraduate biology courses, in this paper, we propose a problem-centered approach that utilizes supplemental web-based instructional materials based on principles of active learning. We compared two supplementary web-based modules using active learning strategies: the first used Merrill’s First Principles of Instruction as a framework for organizing multiple active learning strategies; the second used a traditional web-based approach. Results indicated that (a) the First Principles group gained significantly from pretest to posttest at the Remember level (t(40) = ?1.432, p = 0.08, ES = 0.4) and at the Problem Solving level (U = 142.5, N1 = 21, N2 = 21, p = .02, ES = 0.7) and (b) the Traditional group gained significantly from pretest to posttest at the Remember level (t(36) = 1.762, p = 0.043, ES = 0.6). Those in the First Principles group were significantly more likely than the traditional group to be confident in their ability to solve problems in the future (χ² (2, N = 40) = 3.585, p = 0.09).     

Interleukin-18, matrix metalloproteinase-22 and -29 are independent risk factors of human coronary heart disease

Background

Coronary heart disease (CHD) is characterized by arterial wall inflammation and matrix degradation. Matrix metalloproteinase (MMP)-22 and -29 and pro-inflammatory cytokine interleukin-18 (IL18) are present in human hearts. IL18 may regulate MMP-22 and -29 expression, which may correlate with CHD progression.

Methods and results

Immunoblot analysis showed that IL18 induced MMP-22 expression in human aortic smooth muscle cells. The Mann Whitney test from a prospective study of 194 CHD patients and 68 non-CHD controls demonstrated higher plasma levels of IL18, MMP-22 and -29 in CHD patients than in the controls. A logistic regression test suggested that plasma IL18 (odds ratio (OR)=1.131, P=0.007), MMP-22 (OR=1.213, P=0.040), and MMP-29 (OR=1.198, P=0.033) were independent risk factors of CHD. Pearson’s correlation test showed that IL18 (coefficient (r)=0.214, P=0.045; r=0.246, P=0.031) and MMP-22 (r=0.273, P=0.006; r=0.286, P=0.012) were associated with the Gensini score before and after adjusting for potential confounding factors. The multivariate Pearson’s correlation test showed that plasma MMP-22 levels correlated positively with high-sensitive-C-reactive protein (hs-CRP) (r=0.167, P=0.023), and MMP-29 levels correlated negatively with triglyceride (r=?0.169, P=0.018). Spearman’s correlation test indicated that plasma IL18 levels associated positively with plasma MMP-22 (r=0.845, P<0.001) and MMP-29 (r=0.548, P<0.001).

Conclusions

Our observations suggest that IL18, MMP-22 and -29 serve as biomarkers and independent risk factors of CHD. Increased systemic IL18 in CHD patients may contribute to elevated plasma MMP-22 and -29 levels in these patients.

     

Effects of temperature and diet on length-weight relationship and condition factor of the juvenile Malabar blood snapper (<Emphasis Type="Italic">Lutjanus malabaricus</Emphasis> Bloch &amp; Schneider, 1801)

In this study we aimed to analyze the effects of water temperature and diet on the length-weight relationship and condition of juvenile Malabar blood snapper Lutjanus malabaricus over a 30-d experimental period. The experiment was conducted in the laboratory using a flow-through-sea-water system. The fish were subjected to four different temperatures (22, 26, 30, and 34 °C) and two diets (commercial pellet and natural shrimp). Fish were fed twice daily. L. malabaricus exhibited negative allometric growth (b<3) at the beginning of the experiment (Day 0) at all temperatures and both diets except for 22 °C fed with shrimp, which showed isometric growth (b=3). Conversely, at the end of the experiment (Day 30) fish showed isometric growth (b=3) at 30 °C fed with the pellet diet, indicating that the shape of the fish did not change with increasing weight and length, and a positive allometric growth (b>3) at 30 °C fed with shrimp diet, which indicated that fish weight increases faster than their length. The rest of the temperatures represented negative allometric growth (b<3) on both diet, meaning that fish became lighter with increasing size. The condition factors in the initial and final measurements were greater than 1, indicating the state of health of the fish, except for those fed on a pellet diet at 34 °C. However, the best condition was obtained at 30 °C on both diets. Nevertheless, diets did not have a significant effect on growth and condition of juvenile L. malabaricus. The data obtained from this study suggested culturing L. malabaricus at 30 °C and feeding on the pellet or shrimp diet, which will optimize the overall production and condition of this commercially important fish species.     

An oriental melon 9-lipoxygenase gene <Emphasis Type="Italic">CmLOX09</Emphasis> response to stresses,hormones, and signal substances

In plants, lipoxygenases (LOXs) play a crucial role in biotic and abiotic stresses. In our previous study, five 13-LOX genes of oriental melon were regulated by abiotic stress but it is unclear whether the 9-LOX is involved in biotic and abiotic stresses. The promoter analysis revealed that CmLOX09 (type of 9-LOX) has hormone elements, signal substances, and stress elements. We analyzed the expression of CmLOX09 and its downstream genes—CmHPL and CmAOS—in the leaves of four-leaf stage seedlings of the oriental melon cultivar “Yumeiren” under wound, hormone, and signal substances. CmLOX09, CmHPL, and CmAOS were all induced by wounding. CmLOX09 was induced by auxin (indole acetic acid, IAA) and gibberellins (GA₃); however, CmHPL and CmAOS showed differential responses to IAA and GA₃. CmLOX09, CmHPL, and CmAOS were all induced by hydrogen peroxide (H₂O₂) and methyl jasmonate (MeJA), while being inhibited by abscisic acid (ABA) and salicylic acid (SA). CmLOX09, CmHPL, and CmAOS were all induced by the powdery mildew pathogen Podosphaera xanthii. The content of 2-hexynol and 2-hexenal in leaves after MeJA treatment was significantly higher than that in the control. After infection with P. xanthii, the diseased leaves of the oriental melon were divided into four levels—levels 1, 2, 3, and 4. The content of jasmonic acid (JA) in the leaves of levels 1 and 3 was significantly higher than that in the level 0 leaves. In summary, the results suggested that CmLOX09 might play a positive role in the response to MeJA through the hydroperoxide lyase (HPL) pathway to produce C6 alcohols and aldehydes, and in the response to P. xanthii through the allene oxide synthase (AOS) pathway to form JA.     

Overweight and obesity versus concentrations of VEGF-A,sVEGFR-1, and sVEGFR-2 in plasma of patients with lower limb chronic ischemia

Objective

Being overweight or obese comprises a significant risk factor for atherosclerosis. Fat tissue also generates factors stimulating angiogenesis, the process by which new blood vessels form. The purpose of this paper is to assess concentrations of the vascular endothelial growth factor A (VEGF-A) and its soluble type-1 and type-2 receptors (sVEGFR-1 and sVEGFR-2) in plasma of patients with peripheral arterial disease (PAD) depending on the level of nutrition according to body mass index (BMI).

Methods

The study group included patients suffering from symptomatic PAD (n=46) in Fontaine classes IIa–IV without any history of neoplastic disease and who have a normal BMI (n=15), are overweight (n=21) or are obese (n=10). The control group (n=30) consisted of healthy non-smoking volunteers who were neither overweight nor obese. Venous blood plasma samples were collected from both groups at rest in the morning to determine plasma concentrations of VEGF-A, sVEGFR-1, and sVEGFR-2 using the enzymelinked immunosorbent assay (ELISA) method.

Results

The group of patients with PAD co-existent with being overweight or obese tended to have higher mean concentration levels of VEGF-A and sVEGFR-2 when compared with patients suffering from PAD with normal BMI. A statistically significant positive correlation was obtained between BMI and average plasma concentrations of sVEGFR-2 (R=0.37, P=0.0103). However, no significant correlation was noticed between BMI and VEGF-A or sVEGFR-1 concentrations.

Conclusions

A positive correlation determined between the level of antiangiogenic factor and BMI value may be indicative of the linearly growing prevalence of some antiangiogenic factors in patients with metabolic disorders, which may be one of numerous factors contributing to incomplete efficiency of collateral circulation development in patients with PAD.

     

Fungal spondylodiscitis in a patient recovered from H7N9 virus infection: a case study and a literature review of the differences between <Emphasis Type="Italic">Candida</Emphasis> and <Emphasis Type="Italic">Aspergillus</Emphasis> spondylodiscitis

To report a rare case of fungal spondylodiscitis in a patient recovered from H7N9 virus infection and perform a literature review of the different characteristics of Candida and Aspergillus spondylodiscitis, we reviewed cases of spondylodiscitis caused by Candida and Aspergillus species. Data, including patients’ information, pathogenic species, treatment strategy, outcomes, and relapses, were collected and summarized. The characteristics of Candida and Aspergillus spondylodiscitis were compared to see if any differences in clinical features, management, or consequences could be detected. The subject of the case study was first misdiagnosed as having a vertebral tumor, and then, following open biopsy, was diagnosed as having fungal spondylodiscitis. The patient made a good recovery following radical debridement. Seventy-seven additional cases of Candida spondylodiscitis and 94 cases of Aspergillus spondylodiscitis were identified in the literature. Patients with Candida spondylodiscitis tended to have a better outcome than patients with Aspergillus spondylodiscitis (cure rate 92.3% vs. 70.2%). Candida was found more frequently (47.8%) than Aspergillus (26.7%) in blood cultures, while neurological deficits were observed more often in patients with Aspergillus spondylodiscitis (43.6% vs. 25.6%). Candida spinal infections were more often treated by radical debridement (60.5% vs. 39.6%). Patients with Candida spondylodiscitis have better outcomes, which may be associated with prompt recognition, radical surgical debridement, and azoles therapy. A good outcome can be expected in fungal spondylodiscitis with appropriate operations and anti-fungal drugs.     

Assessments of tear meniscus height,tear film thickness,and corneal epithelial thickness after deep anterior lamellar keratoplasty

Objective

To assess the lower tear meniscus height (LTMH), central tear film thickness (CTFT), and central corneal epithelial thickness (CCET) after deep anterior lamellar keratoplasty (DALK).

Methods

This was a retrospective cross-sectional study of 20 patients who had DALK in one eye over a three-month period. LTMH, CTFT, and CCET of the operated eyes and the unoperated fellow eyes were measured using high-definition optical coherence tomography (HD-OCT). Correlations between three OCT assessments and age, time following surgery, graft size, bed size, and the number of residual sutures were analyzed.

Results

Compared to patients with keratoconus, patients with other corneal conditions had significantly higher CCET in the fellow eye (P=0.024). For all patients, CCET in the operated eye was significantly negatively correlated with the number of residual sutures (R=?0.579, P=0.008), and was significantly positively correlated with time following surgery (R=0.636, P=0.003). In the fellow eye, a significant positive correlation was found between age and CCET (R=0.551, P=0.012), and a significant negative correlation between age and CTFT (R=?0.491, P=0.028). LTMH was found to be significantly correlated between operated and fellow eyes (R=0.554, P=0.011). There was no significant correlation between LTMH and age, bed/graft size, time following surgery, or residual sutures (all possible correlations, P>0.05).

Conclusions

Patients with keratoconus tend to have a thinner central corneal epithelium. Corneal epithelium keeps regenerating over time after DALK. DALK did not induce a significant change in tear volume compared with the fellow eye. Postoperative tear function might depend on an individual’s general condition, rather than on age, gender, bed/graft size, time following surgery, or residual sutures.

     

<Emphasis Type="Italic">Chryseobacterium chengduensis</Emphasis> sp. nov. isolated from the air of captive giant panda enclosures in Chengdu,China

A Gram-negative, aerobic, non-motile, rod-shaped bacterial strain, designated 25-1^T, was isolated from the air inside giant panda enclosures at the Chengdu Research Base of Giant Panda Breeding, China. Strain 25-1^T grew optimally at pH 7.0–8.0, at 28–30 °C and in the presence of NaCl concentrations from 0.0% to 0.5 %. 16S rRNA gene sequence analysis indicated that strain 25-1^T belongs to the genus Chryseobacterium within the family Flavobacteriaceae and is related most closely to C. carnis G81^T (96.4% similarity), C. lathyri RBA2-6^T (95.8% similarity), and C. zeae JM1085^T (95.8% similarity). Its genomic DNA G+C molar composition was 36.2%. The major cellular fatty acids were iso-C_15:0 (44.0%), iso-C_17:0 3OH (19.8%) and C_16:1 ω7c/_16:1 ω6c (12.7%). The only isoprenoid quinone was menaquinone 6 (MK-6). The major polar lipids were phosphatidylethanolamine, two unidentified amino lipids and two unidentified lipids. The DNA-DNA relatedness between strain 25-1^T and C. lathyri RBA2-6^T was 38%. Phenotypic, genotypic, and phylogenetic characteristics indicated that strain 25-1^T is a novel member of the genus Chryseobacterium, for which the name C. chengduensis sp. nov. is proposed. The type strain is 25-1^T (CCTCC AB2015133^T=DSM 100396^T).     

Biomolecular characterization,identification, enzyme activities of molds and physiological changes in sweet potatoes (<Emphasis Type="Italic">Ipomea batatas</Emphasis>) stored under controlled atmospheric conditions

Microbial attacks during storage are one of the primary causes of product deterioration, and can limit the process of prolonging the shelf-life of harvested food. In this study, sweet potatoes were stored at temperatures of 13, 21, and 29 °C for 4 weeks. Samples were collected during storage and plated on potato dextrose agar, from which axenic mold cultures were obtained and identified using 26S rRNA gene sequences. Physiological changes of potato tubers were assessed with respect to pathogenicity, enzyme activity, and atmospheric storage conditions. Six fungal species were identified, namely Penicillium chrysogenum (P. rubens), P. brevicompactum, Mucor circinelloides, Cladosporium cladosporiodes, P. expansum, and P. crustosum. The following fungal isolates, namely P. expansum, P. brevicompactum, and Rhizopus oryzae, were recovered from the re-infected samples and selected according to their levels of enzyme activity. This study revealed high levels of activity for cellulase and pectinase, which were most notable during the initial three days of testing, and were followed by a steady decrease (P<0.05). Polygalacturonase activity was prominent with values ranging from 12.64 to 56.79 U/mg (P. expansum) and 18.36 to 79.01 U/mg (P. brevicompactum). Spoilage was obvious in the control group, which had a 100% decay at the end of the experimental period compared with samples treated with iprodione and sodium hypochlorite, in which the decay rates were 5% and 55%, respectively. The data for the iprodione- and sodium hypochlorite-treated samples at the end of the 3-month storage period showed that they were significantly different (P=0.041), with the sodium hypochlorite-treated samples producing twice the rate of infection compared to the iprodione-treated samples. The comparative rate of the progression of decay in the treated samples can be expressed as iprodione<sodium hypochlorite<control. This study demonstrates that sweet potato tissue damage is due to the activities of microbial enzymes and, in particular, the pectinases of the organisms isolated from the infected potato tissues, and suggests the advantages of utilizing iprodione as a curing agent for potato tubers before storage.     

Measures of instruction for creative engagement: Making metacognition,modeling and creative thinking visible

The purpose of the current study was to estimate reliability, internal consistency and construct validity of the Measure of Instruction for Creative Engagement (MICE) instrument. The MICE uses an iterative process of evidence collection and scoring through teacher observations to determine instructional domain ratings and overall scores. The results demonstrated the sound inter-observer reliability, teacher stability and score validity of the MICE. We found (a) a low proportion of rater variance (0.14–5.99%), (b) moderate to highly correlated within-teacher ratings ranging from r(17) = 0.663, p < 0.01 to r(17) = 1.000, p < 0.01 and (c) a statistically-significant difference between classroom teachers and teaching artists, t(56) = 7.37, p = 0.000. These results relate to the development of classroom environment instruments and the substantive development of pedagogy that supports creative thinking and behaviours, both of which are a priority for enhancing teacher accountability and student learning.     

Haplotype of platelet receptor <Emphasis Type="Italic">P2RY12</Emphasis> gene is associated with residual clopidogrel on-treatment platelet reactivity

Objective

To investigate a possible association between common variations of the P2RY12 and the residual clopidogrel on-treatment platelet reactivity after adjusting for the influence of CYP2C19 tested by thromboelastography (TEG).

Methods

One hundred and eighty patients with acute coronary syndrome (ACS) treated with clopidogrel and aspirin were included and platelet function was assessed by TEG. Five selected P2RY12 single nucleotide polymorphisms (SNPs; rs6798347, rs6787801, rs6801273, rs6785930, and rs2046934), which cover the common variations in the P2RY12 gene and its regulatory regions, and three CYP2C19 SNPs (^*2,^*3,^*17) were genotyped and possible haplotypes were analyzed.

Results

The high on-treatment platelet reactivity (HTPR) prevalence defined by a platelet inhibition rate <30% by TEG in adenosine diphosphate (ADP)-channel was 69 (38.33%). Six common haplotypes were inferred from four of the selected P2RY12 SNPs (denoted H₀ to H₅) according to the linkage disequilibrium R square (except for rs2046934). Haplotype H₁ showed a significantly lower incidence of HTPR than the reference haplotype (H₀) in the total study population while haplotypes H₁ and H₂ showed significantly lower incidences of HTPR than H₀ in the nonsmoker subgroup after adjusting for CYP2C19 effects and demographic characteristics. rs2046934 (T744C) did not show any significant association with HTPR.

Conclusions

The combination of common P2RY12 variations including regulatory regions rather than rs2046934 (T744C) that related to pharmacodynamics of clopidogrel in patients with ACS was independently associated with residual on-clopidogrel platelet reactivity. This is apart from the established association of the CYP2C19. This association seemed more important in the subgroup defined by smoking.

     

Evaluation of the antioxidant property and effects in <Emphasis Type="Italic">Caenorhabditis elegans</Emphasis> of Xiangxi flavor vinegar,a Hunan local traditional vinegar

Xiangxi flavor vinegar (XV) is one of Hunan Province’s traditional fermented vinegars. It is produced from herb, rice, and spring water with spontaneous liquid-state fermentation techniques. In this study, we investigated the antioxidant property of XV by analyzing its antioxidant compounds, its free radical scavenging property in vitro and in vivo, and its effects on antioxidant enzyme activity and apoptosis in Caenorhabditis elegans. The results showed that XV is rich in antioxidants. In particular, ligustrazine reached 6.431 μg/ml. The in vitro 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH^?), hydroxyl radical (^?OH), and superoxide anion radical (O ₂ ^?? ) scavenging rates of XV were 95.85%, 97.22%, and 63.33%, respectively. The reactive oxygen species (ROS) content in XV-treated C. elegans decreased significantly (P<0.01) compared to the control group. Glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities were remarkably increased (P<0.01) in C. elegans after XV treatment. In addition, XV could upregulate CED-9 protein expression and downregulate CED-3 protein expression in C. elegans. These results prove that XV is rich in antioxidants and scavenges radicals in vitro efficiently. XV inhibits apoptosis in C. elegans probably by scavenging ROS and increasing the activities of its antioxidant enzymes.     

<Emphasis Type="Italic">Pediococcus Acidilactici</Emphasis> Inhibit Biofilm Formation of Food-Borne Pathogens on Abiotic Surfaces

In this study, we aimed to examine the inhibitory effect of PA003, a Pediococcus acidilactici that produces lactic acid and antimicrobial peptides pediocin, on pathogenic biofilm formation on abiotic surfaces. PA003 and pathogens (Escherichia coli, Salmonella enterica serovar Typhimurium, Staphylococcus aureus and Listeria monocytogenes) were used to evaluate auto-aggregation, hydrophobicity, biofilm formation and biofilm formation inhibition on stainless steel, polyvinyl chloride and glass slides in terms of exclusion, displacement and competition. The results showed the highest auto-aggregation abilities were observed for one of the E. coli strains EAggEC (E58595) and the highest hydrophobic strain was observed with EPEC (E2348/69) (51.9%). The numbers of biofilm cells of E. coli, S. Typhimurium, S. aureus and L. monocytogenes on stainless steel, polyvinyl chloride and glass slide coupons were effectively reduced by approximately 4 log CFU/coupon. These results demonstrate that lactic acid bacteria can be used as an alternative to effectively control the formation of biofilms by food-borne pathogens.     

Glycyrrhizic acid activates chicken macrophages and enhances their <Emphasis Type="Italic">Salmonella</Emphasis>-killing capacity in vitro

Objective

Salmonella enterica remains a major cause of food-borne disease in humans, and Salmonella Typhimurium (ST) contamination of poultry products is a worldwide problem. Since macrophages play an essential role in controlling Salmonella infection, the aim of this study was to evaluate the effect of glycyrrhizic acid (GA) on immune function of chicken HD11 macrophages.

Methods

Chicken HD11 macrophages were treated with GA (0, 12.5, 25, 50, 100, 200, 400, or 800 μg/ml) and lipopolysaccharide (LPS, 500 ng/ml) for 3, 6, 12, 24, or 48 h. Evaluated responses included phagocytosis, bacteria-killing, gene expression of cell surface molecules (cluster of differentiation 40 (CD40), CD80, CD83, and CD197) and antimicrobial effectors (inducible nitric oxide synthase (iNOS), NADPH oxidase-1 (NOX-1), interferon-γ (IFN-γ), LPS-induced tumor necrosis factor (TNF)-α factor (LITAF), interleukin-6 (IL-6), and IL-10), and production of nitric oxide (NO) and hydrogen peroxide (H₂O₂).

Results

GA increased the internalization of both fluorescein isothiocyanate (FITC)-dextran and ST by HD11 cells and markedly decreased the intracellular survival of ST. We found that the messenger RNA (mRNA) expression of cell surface molecules (CD40, CD80, CD83, and CD197) and cytokines (IFN-γ, IL-6, and IL-10) of HD11 cells was up-regulated following GA exposure. The expression of iNOS and NOX-1 was induced by GA and thereby the productions of NO and H₂O₂ in HD11 cells were enhanced. Notably, it was verified that nuclear factor-κB (NF-κB) and c-Jun N-terminal kinase (JNK) pathways were responsible for GA-induced synthesis of NO and IFN-γ gene expression.

Conclusions

Taken together, these results suggested that GA exhibits a potent immune regulatory effect to activate chicken macrophages and enhances Salmonella-killing capacity.

     

Laparoscopic versus open distal pancreatectomy for pancreatic ductal adenocarcinoma: a single-center experience

Objective

The aim of this study was to compare complications and oncologic outcomes of patients undergoing laparoscopic distal pancreatectomy (LDP) and open distal pancreatectomy (LDP) at a single center.

Methods

Distal pancreatectomies performed for pancreatic ductal adenocarcinoma during a 4-year period were included in this study. A retrospective analysis of a database of this cohort was conducted.

Results

Twenty-two patients underwent LDP for pancreatic ductal adenocarcinoma, in comparison to seventy-six patients with comparable tumor characteristics treated by LDP. No patients with locally advanced lesions were included in this study. Comparing LDP group to LDP group, there were no significant differences in operation time (P=0.06) or blood loss (P=0.24). Complications (pancreatic fistula, P=0.62; intra-abdominal abscess, P=0.44; postpancreatectomy hemorrhage, P=0.34) were similar. There were no significant differences in the number of lymph nodes harvested (11.2±4.6 in LDP group vs. 14.4±5.5 in LDP group, P=0.44) nor the rate of patients with positive lymph nodes (36% in LDP group vs. 41% in LDP group, P=0.71). Incidence of positive margins was similar (9% in LDP group vs. 13% in LDP group, P=0.61). The mean overall survival time was (29.6±3.7) months for the LDP group and (27.6±2.1) months for LDP group. There was no difference in overall survival between the two groups (P=0.34).

Conclusions

LDP is a safe and effective treatment for selected patients with pancreatic ductal adenocarcinoma. A slow-compression of pancreas tissue with the GIA stapler is effective in preventing postoperative pancreatic fistula. The oncologic outcome is comparable with the conventional open approach. Laparoscopic radical antegrade modular pancreatosplenectomy contributed to oncological clearance.

     

Identification of <Emphasis Type="Italic">FECH</Emphasis> gene multiple variations in two Chinese patients with erythropoietic protoporphyria and a review

Erythropoietic protoporphyria (EPP), an autosomal dominant disease, is caused by partial deficiency of ferrochelatase (FECH), which catalyzes the terminal step of heme biosynthesis because of loss-of-function mutations in the FECH gene. To date, only a few cases have been described in Asia. In this study, we describe the clinical features of two Chinese patients with EPP, with diagnosis confirmed by the increase of free protoporphyrin in erythrocytes, detection of plasma fluorescence peak at 630–634 nm, and analysis of FECH gene mutations. Using gene scanning, we identified a small deletion in the FECH gene (c.973 delA) in one proband (patient A) and a pathogenic FECH mutation (c.1232 G>T) in the other (patient B) and also observed some nucleotide variations (c.798 C>G, c.921 A>G, IVS1?23 C>T, IVS3+23 A>G, IVS9+35 C>T, and IVS3?48 T>C) in these patients. The family pedigree of patient A was then established by characterization of the genotype of the patient’s relatives. We also analyzed the potential perniciousness of the missense mutation with bioinformatic software, Polyphen and Sift. In summary, Chinese EPP patients have similar manifestations to those of Caucasians, and identification of the Chinese FECH gene mutations expands the FECH genotypic spectrum and may contribute to genetic counseling.     

Characterization of the mean velocity of a circular jet in a bounded basin

A circular jet has broad and important applications in practical engineering. Most research in this area has focused on a free jet, a wall jet or a vertical jet in a bounded domain. In this study, the mean velocities of circular offset jets were studied for four jet exit Froude numbers (Fr), three offset heights (S) (S/d=1, 2, 3) and three submergence ratios (ht/S) (surface jet, mixed jet, and submerged jet) in a bounded basin. Based on the results, we propose a velocity decay formula for a circular jet. The lateral velocity spread was more consistent with Gaussian and Cauchy–Lorentz distributions than the vertical velocity. Moreover, Fr had little effect on the decay of the mean velocity for a circular jet when Re>1×10⁴. The lateral and vertical spreads showed a quadratic relationship with the streamwise distance for different values of Fr at X/d<10. The positions of maximum mean velocity decay were independent of Fr and S/d when X/d<10. The spread rate was more uniform in the lateral direction than that in the vertical direction in a certain region for different S/d and ht/S. Therefore, the decay, spread, and maximum velocity position of the mean velocity for a circular offset jet can remain stable under different values of Fr, offset height, and submergence ratio.