bluuebunny/crossref_metadata_2025 huggingface dataset:
Topoisomerase I activity in squamous cell carcinoma of the head and neck
Authors: Masin Jeffrey S. , Berger Sosamma J. , Setrakian Sebouh , Stepnick David W. , Berger Nathan A.
Published: October 2006

In recent preclinical and clinical trials, topoisomerase I inhibitors have shown great promise as antitumor agents. These agents are most effective against tumors with high topoisomerase I activity. Therefore, determining topoisomerase I activity in advance may predict response to topoisomerase I inhibitors.

Squamous cell carcinoma of the head and neck and normal tissue samples were obtained from 12 patients. Cellular extracts were prepared, and topoisomerase I activity assays were performed. The results suggest that topoisomerase I activity in squamous cell carcinoma of the head and neck is increased approximately sixtyfold compared to normal tissue.

Increased activity often correlates with clinical responsiveness; these results predict that topoisomerase I inhibitors should be effective and selective against squamous cell carcinoma of the head and neck.
Gastroesophageal reflux prophylaxis decreases the incidence of pharyngocutaneous fistula after total laryngectomy
Authors: Seikaly H. , Park P.
Published: October 2006

Pharyngocutaneous fistula is a serious complication after laryngectomy. Gastric fluid is known to cause severe laryngopharyngeal injury and poor mucosal healing. This study was designed to evaluate the effects of a gastroesophageal reflux prophylaxis regimen on the incidence of fistula after laryngectomy. Twenty‐one consecutive patients were entered in the study. Patients with positive resection margins were excluded from the overall analysis. All patients had a Connell's two‐layer closure of the pharynx with absorbable suture, suction drainage of the neck, postoperative tube feeding, and prophylactic antibiotics. All patients were started on an antireflux regimen postoperatively composed of continuous tube feeds, intravenous ranitidine, and intravenous metoclopramide hydrochloride. Patients were followed postoperatively with Gastrografin swallows and clinically for 8 weeks. The control group consisted of retrospectively studied patients managed identically except for the antireflux prophylaxis. The two groups were well matched for factors reported to influence the rate of pharyngocutaneous fistula formation. The control group had six fistulae (26%) and an average of 16.5 days of hospital stay. The study group had no fistulae and an average of 11.5 days of hospital stay (P = .02). This study suggests that gastroesophageal reflux may predispose to fistula formation after laryngectomy and that mechanical and pharmacological prophylaxsis decreases postoperative morbidity and length of hospital stay.
Dynamic MRI‐guided interstitial laser therapy: A new technique for minimally invasive surgery
Authors: Pushek T. , Jongewaard N. , Castro D. J. , Paiva M. , Saxton R. E. , Farahani K. , Lufkin R. , Soudant J.
Published: October 2006

Interstitial laser therapy (ILT) is a promising therapeutic technique in which laser energy is delivered percutaneously to various depths in tissue. In this study, the authors compared high‐speed magnetic resonance imaging (MRI) of ILT in tissues during treatment with post‐treatment histopathologic specimens. The use of 5‐second MRI scans allowed detection of thermal damage by the 1064‐nm neodym‐ium:yttrium‐aluminum‐garnet laser in ex vivo liver and brain tissues. These tissues were treated by ILT with 20 W of laser output for 5 to 30 seconds via a 600‐μm fiberoptic inserted 1 cm into the specimens at a power density of 7 kW/cm2 at the tip of the bare fiber.

Sequential MRI measurements of lesion areas made during and after treatment were compared to measurements of laser‐induced tissue damage in his‐tolopathologic sections. Fast MRI scans and tissue histology both demonstrated increased lesion size with time of ILT. Serial images obtained during ILT detected thermal changes as areas of low signal intensity that exceeded the size of the post‐treatment lesions as measured on either final MRI or histology. The thermal effects detectable by these high‐speed MRI sequences can be used to monitor laser‐induced tissue changes during therapy, thereby providing a valuable noninvasive method for the intraoperative assessment of heat distribution during ILT.
The Meaning of Work: Conceptualizing the Deterrent Effect of Employment on Crime among Young Adults
Authors: Wadsworth Tim
Published: October 2006

Data from the National Longitudinal Survey of Youth (NLSY) are used to examine the influence of employment characteristics and other age-appropriate investments on young adults' participation in both violent and property crime. The findings suggest that quality of employment has a stronger influence on individuals' involvement in both economic and noneconomic criminal behavior than do income, job stability, educational achievement, and a variety of background factors. The implications of these findings for theoretical development and public policy are discussed.
Socioethical issues in Hospital Birth: Troubling Tales from a Canadian Sample
Authors: Rosenthal M. Sara
Published: October 2006

Prior to the writing of this article, a small qualitative Canadian study surveyed prenatal counseling in a hospital setting; through that study, unexpected and disturbing narratives emerged from participants about their labors and deliveries. The absence of prenatal counseling and consent, in some cases, led to psychosocial trauma, perpetuated by false assumptions participants made about the safety of hospital birth. These were findings in a university-college-educated sample that had unique access to excellent health care through a wide variety of quality university teaching hospitals. This sample demonstrated alarming gaps in knowledge about the realities of hospital birth and, more generally, prenatal care in a hospital setting. This article focuses on these hospital birth narratives and discusses them in a sociological and ethical context.

The findings point to further study in urban U.S. settings, with a larger, more diversely educated sample, to determine whether these findings are unique to the Canadian health-care system, unique to a more educated sample of women, or more universal, pointing to a broader need for obstetrical care reform.
Hyperinsulinemia in Healthy Children and Adolescents With a Positive Family History for Type 2 Diabetes
Authors: Rodríguez-Morán Martha , Guerrero-Romero Fernando
Published: October 2006

OBJECTIVE. Our goal was to determine the relationship between family history of type 2 diabetes and fasting hyperinsulinemia in healthy children and adolescents.

METHODS. A total of 317 children and adolescents, 10 to 14 years of age with Tanner stage 1 or 2, were randomly selected from elementary and middle schools in Durango, northern Mexico, to participate in a cross-sectional, community-based study. Family history was ascertained by a direct, detailed medical examination that included anthropometric and laboratory measurements from both parents. We determined the prevalence of family history of type 2 diabetes, high blood pressure, obesity, hyperinsulinemia, and the adjusted odds ratio that computes the relationship between hyperinsulinemia and family history of type 2 diabetes.

RESULTS. Family history of type 2 diabetes, high blood pressure, and obesity was recognized in 30 (9.2%), 61 (18.7%), and 74 (22.7%) children and adolescents, respectively. Children and adolescents with positive family history showed higher systolic and diastolic blood pressure, were more obese, and exhibited significantly higher fasting insulin and triglycerides levels, as well as a higher homeostasis model analysis insulin resistance index, than children with negative family history. A total of 48 (15.1%) children and adolescents exhibited hyperinsulinemia, 35 (72.9%) with and 13 (27.1%) without family history. The odds ratio adjusted by gender, fat mass (kilograms and percent), waist circumference, BMI, and Tanner stage showed that family history of diabetes, but not high blood pressure and obesity, was independently related with hyperinsulinemia.

CONCLUSIONS. Among children and adolescents, family history of diabetes, but not high blood pressure and obesity, is independently associated with hyperinsulinemia.
Parent Reports of the Psychosocial Functioning of Children with Cleft Lip and/or Palate
Authors: Hunt Orlagh , Burden Donald , Hepper Peter , Stevenson Mike , Johnston Chris
Published: October 2006

Objectives:

(1) to determine the opinion of parents regarding the psychosocial functioning of their child with cleft lip and/or palate (CLP); (2) to identify predictors of psychosocial functioning; and (3) to determine the level of agreement between children with CLP and their parents.

Participants:

One hundred twenty-nine parents of children with CLP and 96 parents of children without CLP participated in this cross-sectional study.

Outcome measures:

Parental opinion of the child's self-esteem, anxiety, happiness, and problems caused by facial appearance were assessed using visual analogue scales. Parents completed the Child Behavior Checklist and were interviewed.

Results:

Children with CLP were more anxious (p < 0.05), less happy with their appearance (p < 0.001), and in general (p < 0.05) had lower self-esteem (p < 0.05) and greater behavioral problems (p < 0.001) compared with non-CLP children. Parents reported that their child with CLP was teased more often (p < 0.001) and was less satisfied with his/her speech (p < 0.01) compared with reports of parents in the control group. A number of factors affected parents’ ratings of their child's psychosocial functioning (presence of CLP, appearance happiness, previous history of CLP, and visibility of scar). Children who had been teased were more anxious (p ≤ 0.01), less happy with their appearance (p < 0.001) and had greater behavioral problems (p < 0.001).

Conclusions:

Parents of children with CLP reported various psychosocial problems among their children. Parents considered children who had been teased to have greater psychosocial problems.
3D modelling of sprayed-concrete-lined tunnels in clay
Authors: Yazdchi M. , Macklin S. R. , Yeow H.-C.
Published: October 2006

Realistic finite element (FE) modelling of the tunnel construction process has been restricted by the computational effort needed to incorporate the three-dimensional (3D) aspects of the tunnelling operation. Two-dimensional (2D) plane-strain models have therefore been widely adopted by practitioners and researchers in their studies of the effects of tunnelling. However, 2D modelling suffers the drawback whereby a volume loss must be assumed at the outset as the input for the FE model. This paper presents an analysis of measured surface ground movements induced by a sprayed concrete lined tunnel in London Clay. This was achieved using computationally efficient, non-linear, 3D modelling and Oasys LS-DYNA software. By modelling the problem using a non-linear small strain BRICK soil model, which incorporates anisotropic behaviour, good agreement with the actual Gaussian distribution of surface settlement was obtained. This was achieved without any initial assumptions regarding volume loss, but rather by realistically modelling the excavation sequence and time-dependent gain in lining strength. On the basis of this work it is considered that 3D modelling techniques can provide an effective means to estimate ground settlement and the associated effects on nearby structures, without dependence on empirical methods alone.
Analysis of flows and water levels near tidal flap gate
Authors: Mitchell S. B. , Tinton E. , Burgess H.
Published: October 2006

A method is proposed for assessing the impact of rising sea levels on areas upstream of tidal flap gates. These devices, designed to allow drainage of surrounding land during low water and flood defence during high water, are commonly used in areas where tidal high water level is higher than the level of the land behind the sea wall. Studies were undertaken at Pagham Harbour, West Sussex, UK, where a number of tidal flap gates are used to control the flow of water from channels carrying drainage waters away from the nearby town of Chichester. On one of these channels, water level data were collected at 15-min intervals at three sites near the flap gate and analysed in order to obtain values over each tidal cycle of maximum and minimum water levels downstream of the gate, and the time of closure of the gate. Water level was also monitored at two locations upstream of the gate. By obtaining estimates of mean fresh water discharge for each tidal cycle, and combining these with peak tidal water level, a functional relationship (in the form of a three-dimensional plot) was obtained for the parameter tc, the length of time in hours for which the flap gate is closed during each tidal cycle. These values of tc were also used in conjunction with mean tidal fresh water discharge to produce another three-dimensional plot showing the effect on peak tidal water level upstream of the flap gate, thus providing an illustration of the sensitivity of local flooding to varying tc under different tidal conditions. Finally an estimate was made of the likely impact of a 300 mm rise in mean sea level on tc for the same set of fresh water flow data, using a set of ‘look-up’ tables based on the three-dimensional plots obtained. These indicated that the frequency of local flooding was likely to increase significantly for fresh water flows greater than 0·8 m3/s. Although the increase in local flooding illustrated here is not thought to be a cause for immediate concern, particularly in view of the recent construction of a further tidal flap gate adjacent to the existing one, nevertheless the methodology employed is applicable to similar systems.
Application of simulation modelling to harbour operations
Authors: Khatiashvili S. , Bakeev C. , Fidler M.
Published: October 2006

This paper focuses on the use of computer simulation to model harbour operations at the Port of Dover. The objective was to determine the maximum acceptable number of ferry movements in the manoeuvring area off the Eastern Docks. A three-stage methodology was used for the development of the model to ensure the success of the project. During the first stage, port operations data were closely studied to isolate normal operations under ideal conditions from the more uncommon operations and incidents. The second stage of the work involved a manual simulation exercise that provided an opportunity to initiate a discussion between the ferry operators. This further served as a validation exercise for the data gathered during the previous stage. Finally, a computer model of the Eastern Docks was built using Arena simulation software to mimic the ferry movements. The simulation model was then used as a research tool to observe and quantify the effects of variations to the port operational practices and traffic levels. The scope of the work also included the consideration of external factors such as marginal or limiting weather conditions.
Briefing: Maritime London
Authors: Freer R.
Published: October 2006

Although London is no longer a major working port, it is still recognised throughout the world as the leading centre for international maritime services. The separate companies providing these services recognise the need to create commercial clusters which will maintain within London a critical mass of diverse skills. To support this principle of clusters and to maintain the critical mass the Corporation of London has helped to set up an organisation called Maritime London, through which the individual companies can promote their services in this country and overseas, and the Corporation has recently published a report on the future of the Maritime Services in London. This report recognises that there are pressures on such clusters caused by high costs at home and by competition from new maritime countries overseas, and it puts forward proposals to ensure the companies providing these services retain their present commercial position. The first priority is for central and local government to play a much greater role and to provide more support through organisations such as the London Development Agency. These proposals were presented and discussed at a recent well-attended meeting of the associate Parliamentary Maritime Group.
Briefing: News from the Maritime Board
Authors: Leung-Philpot J.
Published: October 2006

This article discusses the role, objectives and recent activities of the Institution of Civil Engineers' Maritime Board and Associated Societies: International Navigation Association, Central Dredging Association and Offshore Engineering Society. In particular, key initiatives and recent issues addressed by the Maritime Board and Associated Societies are highlighted including responding on behalf of the Institution and its members to government consultations including the Marine Bill Consultation, the Transport Committee's Inquiry into the UK Ports Industry and Port Policy Directive. Further, the Board and Associated Societies engage in learned society activities including hosting conferences, lectures and setting up expert groups to exchange technical information. Finally, initiatives to inform members better of the Board's activities and disseminate relevant information to the maritime community are outlined.
In‐field evaluation of the modulation transfer function and the signal‐to‐noise ratio of electronic‐display devices
Authors: Roehrig Hans , Gaskill Jerry , Fan Jiahua , Martin Chadwick , Greivenkamp John , Samei Ehsan
Published: October 2006

Abstract— This paper describes a charged‐coupled device (CCD) camera, which was developed for in‐field evaluation of the image quality of electronic‐display devices [such as cathode‐ray tubes (CRTs) and liquid‐crystal displays (LCDs)] used for medical applications. Contrary to traditional cameras for display‐image‐quality evaluation, this CCD camera does not require a sophisticated x‐y‐z translation stage for mounting and adjustment. Instead, it is handheld and pressed by gentle pressure against the display screen. It is controlled by a software package which was originally developed for display calibration according to the DICOM 14 gray‐scale standard display function (GSDF). This software package controls the camera gain when measurements are made at different display luminance, display test patterns, performs image analysis and displays the results of the measurements and calculations. The work concentrated on the measurement of modulation transfer function (MTF) and of signal‐to‐noise ratio (SNR) per display pixel. The MTF is derived from the Fourier transform of the line spread function (LSF). The single‐display‐pixel SNR is derived from the integration of the noise power spectrum (NPS) of a camera image taken of a display with a uniform luminance. It is demonstrated that the device can produce repeatable results in terms of MTF and SNR. MTFs were measured on three monochrome CRTs and five monochrome LCDs in order to study repeatability and similar quantities. The MTF was measured on a 5‐Mpixel LCD yielding values that lie within 3.5% of the average MTF at the Nyquist frequency and 4.0% of the maximum total sharpness (∫ MTF2 df). The MTF was also measured on a 9‐Mpixel LCD, yielding values that lie within 9.0% of the average MTF at the Nyquist frequency and 8.0% of the maximum total sharpness. The SNR was measured eight times on a 3‐Mpixel monochrome LCD at nine digital driving levels (DDLs). At a DDL of 185, the mean SNR was 15.694 and the standard deviation (Stdv) was 0.587. At a DDL of 65, the mean SNR was 5.675 and Stdv was 0.120.
A photographic technique for assessing the viewing‐angle performance of liquid‐crystal displays
Authors: Fetterly Kenneth A. , Samei Ehsan
Published: October 2006

Abstract— Liquid‐crystal displays (LCDs) have notable variation in luminance and perceived contrast as a function of the angle from which they are viewed. Though this is an important performance issue for LCDs, most evaluation techniques for assessing this variation have been limited to laboratory settings. This study demonstrates the use of a photographic technique for such an evaluation. The technique is based on an actively cooled charge‐coupled‐device (CCD) detector in combination with a macro lens covering a circular angular range (θ) of ±42.5°. The camera was used to evaluate the luminance and perceived contrast properties of an LCD. Uniform field images corresponding to 17 equally spaced gray‐scale values in the digital driving level (DDL) range of the display system were acquired. The 12‐bit gray‐scale digital images produced by the camera were converted to luminance units (cd/m2) via the measured luminance vs. DDL response function of the camera. The changes in perceived contrast as a function of viewing angle were derived from the Barten model of the gray‐scale response of the human‐visual system using the methods proposed by the AAPM TG18 Report. The results of this photographic technique were compared to measurements acquired from a similar display using a Fourier‐optics‐based luminance meter. The results of the two methods generally agreed to within 5%. The photographic methods used were found to be accurate and robust for in‐field assessment of the angular response of LCDs over the FOV of the camera.
Quality assessment of false‐colored fused displays
Authors: Dixon Timothy D. , Fernández Canga Eduardo , Nikolov Stavri G. , Troscianko Tom , Noyes Jan M. , Bull Dave R. , Canagarajah C. Nishan
Published: October 2006

Abstract— The problem of assessing the quality of fused images (composites created from inputs of differing modalities, such as infrared and visible light radiation) is an important and growing area of research. Recent work has shown that the process of assessing fused images should not rely entirely on subjective quality methods, with objective tasks and computational metrics having important contributions to the assessment procedure. The current paper extends previous findings, applying a psychophysical selection task, metric evaluation, and subjective quality judgments to a range of fused surveillance images. Fusion schemes included the contrast pyramid and shift invariant discrete wavelet transform (Experiment 1), the complex wavelet transform (Experiments 1 & 2), and two false‐coloring methods (Experiment 2). In addition, JPEG2000 compression was applied at two levels, as well as an uncompressed control. Reaction time results showed the contrast pyramid to lead to slowest performance in the objective task, whilst the presence of color greatly reduced reaction times. These results differed from both the subjective and metric results. The findings support the view that subjective quality ratings should be used with caution, especially if not accompanied by some task.
An alternate method for using a visual discrimination model (VDM) to optimize softcopy display image quality
Authors: Chakraborty Dev P.
Published: October 2006

Abstract— Researchers have developed visual discrimination models (VDMs) that can predict a human observer's ability to detect a target object superposed on an image. These models incorporate sophisticated knowledge of the properties of the human‐visual system. In the predictive approach, termed conventional VDM usage, two input images with and without a target are analyzed by an algorithm that calculates a just‐noticeable‐difference (JND) index, which is a taken as a measure of the detectability of the target. Anewmethod of using the VDMis described, termed channelized VDM, which involves finding the linear combination of the VDM‐generated channels (which are not used in conventional VDM analysis) that has optimal classification ability between normal and abnormal images. The classification ability can be measured using receiver operating characteristic (ROC) or two alternative forced choice (2AFC) experiments, and in special cases they can also be predicted by signal detection theory (SDT) based model‐observer methods. In this study, simulated background and nodule containing regions were used to validate the new method. It was found that the channelized VDM predictions were in excellent qualitative agreement with human‐observer validated SDT predictions. Either VDM method (conventional or channelized) has potential applicability to softcopy display optimization. An advantage of any VDM‐based approach is that complex effects, such as visual masking, are automatically accounted for, which effects are usually not included in SDT‐based methods.
Using the human observer to assess medical image display quality
Authors: Krupinski Elizabeth A.
Published: October 2006

Abstract— Image quality is an important component in the evaluation of medical imaging systems and can be measured at a number of points between acquisition and display. However, from the perspective of the clinician, the quality of the image that is presented to the eye‐brain system is the most critical since this is what the diagnostic interpretation is derived from. This paper will discuss some ways to assess the design and optimization of display systems in reference to the human observer. The paper will include various approaches to study this issue, including Receiver Operating Characteristic studies, modeling of the human‐visual system, and the use of eye‐position tracking methods. The goal is to demonstrate not only the importance of assessing the impact of display image quality on diagnostic performance, but also on how it can affect workflow and user‐comfort levels.
A Reminder of the Limitations in Using Beer's Law to Estimate Daily Radiation Interception by Vegetation
Authors: Sinclair Thomas R.
Published: October 2006

Radiation extinction coefficients for leaf canopies are often calculated using Beer's Law based on midday measurements of radiation interception. However, the assumption of Beer's Law is not appropriate for leaf canopies and this empirical approach needs to be used with caution. Alternatively, classic derivations of radiation interception by leaf canopies have resulted in a similar exponential form defined as a function of time of day, day of year, and latitude. A common experimental approach of determining the extinction coefficient from midday measurements results in a minimum coefficient that underpredicts the total daily radiation interception. Two approaches are explored to improve the estimates of daily radiation interception under a clear sky. The first approach compared extinction coefficients calculated for midday against ones calculated as representative of radiation interception over the entire day. A linear correlation was found between the two extinction coefficients so that the midday extinction coefficient could be corrected to obtain a coefficient representative of the entire day under a clear sky. The second approach estimated the time of day when measurements could be made to obtain directly an extinction coefficient representative of the entire day. While such times in the day could be identified, this approach is impractical because the periods for taking these measurements are short and dependent on leaf angle.
Genetic Variation in Cynodon transvaalensis Burtt‐Davy
Authors: Kenworthy Kevin E. , Taliaferro Charles M. , Carver Brett F. , Martin Dennis L. , Anderson Jeffrey A. , Bell Gregory E.
Published: October 2006

Cynodon transvaalensis Burtt‐Davy (African bermudagrass) is used as a turfgrass and in interspecific hybridization to produce turfgrass cultivars. Information is lacking on the magnitude of intra‐specific genetic variation for traits related to turfgrass performance. A Design II mating population comprised of 320 F1 plants (4 parental sets, 16 crosses set−1, 5 F1 hybrids cross−1) was used to estimate genetic parameters for 21 traits. The F1 plants were evaluated in replicated field (13 traits) and greenhouse (8 traits) experiments in Stillwater, OK during 2002–2003. Genetic variation was detected for 17 of the 21 traits as indicated by significant (P < 0.05) differences among families within sets. Both additive and dominance genetic effects were detected for most of the 17 traits, but dominance effects usually prevailed over additive effects. Broad sense heritability estimates varied from 0.42 to 0.96. Population improvement via recurrent selection techniques would be possible but difficult as indicated by low levels of additive genetic variation for genetic color, raceme number, seed number, and percent seed set. Dominance effects might be exploited to select clonally propagated F1 hybrid cultivars with enhanced sensor‐rated color, density, turf quality, spring greenup, fall dormancy, percent living cover, raceme number, raceme length, number of florets per inflorescence, plant height, stolon length, number of internodes, internode length, and leaf length.
Alfalfa Fiber Estimation in Mixed Stands and Its Relationship to Plant Morphology
Authors: Parsons D. , Cherney J. H. , Gauch H. G.
Published: October 2006

In New York, most alfalfa (Medicago sativa L.) is grown in mixed stands with grass, and models for estimating neutral detergent fiber (NDF) are not used. The objectives of this experiment were to test the suitability of existing equations for estimating NDF of the alfalfa component of mixed stands, and to better understand how alfalfa is affected by the presence of grass. Stands of first‐cut alfalfa and grass (10–90% grass) were sampled at two experimental sites and producers' fields in 19 New York counties during May and June 2004 and 2005. A range of plant measurements and environmental characteristics were recorded. The predictive equations for alfalfa quality (PEAQ) and other models were examined for applicability to mixed stand alfalfa NDF estimation. The R 2 values ranged from 0.80 to 0.87 and RMSE ranged from 20.5 to 25.2 g kg−1 The most biased model was PEAQ, possibly due to the lower cutting height used to generate the PEAQ equation than the cutting height used in this study. For producer fields, a model based on alfalfa height was the best one‐variable model, with R 2 of 0.84 and RMSE of 22.7 g kg−1 Presence of grass increases the number of nodes and increases alfalfa height; however, the relationship between alfalfa height and NDF is not changed, suggesting that the predictive ability of models based on alfalfa height is not affected by the percentage of grass in the sward.
Molecular Marker‐Assisted Selection for Improved Cooking and Eating Quality of Two Elite Parents of Hybrid Rice
Authors: Liu Qiao‐Quan , Li Qian‐Feng , Cai Xiu‐Ling , Wang Hong‐Mei , Tang Shu‐Zhu , Yu Heng‐Xiu , Wang Zong‐Yang , Gu Ming‐Hong
Published: October 2006

Long‐te‐fu (LTF) and Zhan‐shan 97 (ZS) are two key female parents for the generation of indica hybrid rice, which have greatly contributed to the achievement of rice production in China. However, the high amylose content (AC) in the endosperm, controlled by the Waxy (Wx) gene encoded granule‐bound starch synthase I, of both lines results in poor cooking and eating quality of the milled rice. Our previous studies have shown that AC was correlated with the ability to excise intron 1 from the leader sequence of the Wx transcript, and which is responsible by a single nucleotide polymorphism (G or T) located at the first nucleotide of the splice donor site of Wx intron 1. Thus, a CAPS marker was subsequently developed, and with this molecular marker‐assisted selection (MAS) we successfully introgressed the Wx‐TT locus of rice cultivars with good quality intermediate AC into LTF‐B and ZS‐B. These were subsequently introduced into their relevant male‐sterile lines (LTF‐A and ZS‐A) to generate improved indica hybrids. In the selected lines LTF(tt)‐B and ZS(tt)‐B, the AC was reduced to a relatively low level (15%). Consequently, the hybrids crossed from the selected lines had dramatically reduced amylose levels. In the field trials, the agronomic performance in the improved lines and their hybrids was examined and compared to the originals. The other key factors involved in rice cooking and eating quality were also improved in the selected lines and their hybrids.
Age and Probability of Spontaneous Umbilical Hernia Closure
Authors: He Katherine , Graham Dionne A. , Vernacchio Louis , Hatoun Jonathan , Patane Laura , Cramm Shannon L. , Rangel Shawn J.
Published: March 2024

This cohort study of children younger than 6 years uses electronic health records to investigate whether a child’s age is associated with the probability of spontaneous umbilical hernia closure and to refine guidelines for surgical repair.
Pathways for MXenes in Solving the Issues of Zinc‐Ion Batteries: Achievements and Perspectives
Authors: Zhao Rui , Liu Chang , Zhu Yirong , Zou Guoqiang , Hou Hongshuai , Ji Xiaobo
Published: March 2024

Zinc‐ion batteries (ZIBs) have become a global research hotspot in recent years due to their eco‐friendliness, safety, abundant resources, and low cost. However, some significant challenges seriously affect their overall performance, thus hindering their further development and practical applications. Recently, multifunctional and adjustable 2D carbides and nitrides (MXenes) are extensively used for the modification of ZIBs, and fruitful achievements are achieved. In order to make a systematic understanding of these studies, it is highly desirable to provide an overview of MXenes based on their modification methods and action mechanisms. In this review, a basic introduction to ZIBs and MXenes is presented and the main modification approaches of MXenes in solving the issues of ZIBs are discussed in detail, including activation and composite strategies of the cathode, interface engineering, structural optimization, and zinc metal‐free anode strategy of the anode, solid‐state strategy of the electrolyte, and functionalized strategy of the separator. Importantly, the functions and related mechanisms of MXenes in various components of ZIBs are analyzed in depth. Finally, the pathways for MXenes in solving the issues of ZIBs are summarized, and their future directions are prospected.
A Nucleobase‐Driven Self‐Gelled Hyaluronic Acid‐Based Injectable Adhesive Hydrogel Enhances Intervertebral Disc Repair
Authors: Yang Rong , Wang Biao , Zhang Xiaoping , Sun Yage , Zhang Yiming , Xu Ziyang , Yang Qiang , Liu Wenguang
Published: March 2024

Cell therapy strategies hold great promise for nucleus pulposus (NP) regeneration and intervertebral disc degeneration (IVDD) treatment. However, their therapeutic efficiency is compromised by the anoikis of administered cells and the harsh environment in degenerated intervertebral discs (IVD). Inspired by the ability of nucleobases to form multiple H‐bonds, a nucleobase‐driven self‐gelling strategy is proposed for the incorporation of nucleobases (e.g., thymine) into hyaluronic acid (HA) chains to trigger gel formation through enhanced intermolecular H‐bond interactions. An aqueous solution of a thymine‐modified HA (HAT) supramolecular polymer is shown to exhibit self‐gelation behavior, injectability, tissue adhesion, and hydration capacity (comparable to that observed in the NP tissue of a 25‐year‐old adult). These characteristics enable the injection and filling of the HAT hydrogel system in the IVD, integration of the separated NP tissues, restoration of the biomechanical functions of the degenerated IVD, and securing of the encapsulated cells in the NP site. Manganese dioxide (MnO2) nanoparticles incorporated into the HAT system (HATMn) regulate oxidative stress and the hypoxic microenvironment in degenerated IVD, ensuring the viability of the encapsulated cells. The 12‐week in vivo study results demonstrate that the administration of the MSCs‐laden HATMn system (HATMn‐MSCs) effectively restores the structure and function of degenerated IVD.
Insect‐Scale Biped Robots Based on Asymmetrical Friction Effect Induced by Magnetic Torque
Authors: Zhao Jinsheng , Xin Chen , Zhu Jiaqi , Xia Neng , Hao Bo , Liu Xurui , Tan Yu , Yang Shihao , Wang Xin , Xue Junnan , Wang Qinglong , Lu Haojian , Zhang Li
Published: March 2024

Multimodal and controllable locomotion in complex terrain is of great importance for practical applications of insect‐scale robots. Robust locomotion plays a particularly critical role. In this study, a locomotion mechanism for magnetic robots based on asymmetrical friction effect induced by magnetic torque is revealed and defined. The defined mechanism overcomes the design constraints imposed by both robot and substrate structures, enabling the realization of multimodal locomotion on complex terrains. Drawing inspiration from human walking and running locomotion, a biped robot based on the mechanism is proposed, which not only exhibits rapid locomotion across substrates with varying friction coefficients but also achieves precise locomotion along patterned trajectories through programmed controlling. Furthermore, apart from its exceptional locomotive capabilities, the biped robot demonstrates remarkable robustness in terms of load‐carrying and weight‐bearing performance. The presented locomotion and mechanism herein introduce a novel concept for designing magnetic robots while offering extensive possibilities for practical applications in insect‐scale robotics.
Hybrid anionic block copolymerization: From organocatalysis‐streamlined crossover to internally microphase‐separated aggregates
Authors: Liu Lijun , Li Heng , Zhang Pengfei , Zhou Yubo , Zhao Junpeng , Zhang Guangzhao
Published: March 2024

Polyolefin‐b‐poly(ethylene oxide) (PEO) represents the most widely investigated amphiphilic block copolymers. So far, one‐pot continuous synthesis of such hybrid block copolymers has only been fulfilled by anionic polymerization through sequential addition of vinyl monomers and ethylene oxide (EO). It still remains challenging to achieve altogether high block efficiency, high polymerization efficiency, and high molar mass for PEO. Here, we report a one‐pot hybrid block copolymerization approach to polyisoprene/polystyrene(PI/PS)‐b‐PEO, in which PI/PS are formed by sBuLi‐initiated anionic vinyl‐addition polymerization, then in situ employed as macroinitiators for the anionic ring‐opening polymerization (ROP) of EO aided by an organic Lewis pair. The cooperative (dual‐ion‐complexing) catalytic effect of organobase and triethylborane is proven, for the first time, effective for lithium alkoxide initiator system, allowing to achieve at room temperature high ROP activity (complete EO conversion and PEO of 3–64 kg/mol reached in 1–6 h), narrow molar mass distribution, controlled block lengths and composition. Density functional theory calculation shows that phosphazene bases are particularly effective, compared with N‐heterocyclic bases, for complexing with Li+ and enhancing the nucleophilicity of oxyanion. The rate of ROP is also affected by Li+‐induced aggregation of the chain‐end ion pairs, which though can be offset by adequate catalyst loadings. The versatility of this approach is further demonstrated in the one‐pot synthesis of tri‐/tetrablock ter‐/quaterpolymers constituted by PI, PS, PEO, and poly(propylene oxide). Of great interest, PS‐b‐PI‐b‐PEO triblock terpolymer with a specific composition is found to form internally microphase‐separated micellar aggregates when dispersed in water.
Correlation between Heteroatom Coordination and Hydrogen Evolution for Single‐site Pt on Carbon‐based Nanocages
Authors: Cheng Xueyi , Mao Chenghui , Tian Jingyi , Xia Minqi , Yang Lijun , Wang Xizhang , Wu Qiang , Hu Zheng
Published: March 2024

The electrocatalytic performance of single‐site catalysts (SSCs) is closely correlated with the electronic structure of metal atoms. Herein we construct a series of Pt SSCs on heteroatom‐doped hierarchical carbon nanocages, which exhibit increasing hydrogen evolution reaction (HER) activities along S‐doped, P‐doped, undoped and N‐doped supports. Theoretical simulation indicates a multi‐H‐atom adsorption process on Pt SSCs due to the low coordination, and a reasonable descriptor is figured out to evaluate the HER activities. Relative to C‐coordinated Pt, N‐coordinated Pt has higher reactivity due to the electron transfer of N‐to‐Pt, which enriches the density of states of Pt 5d orbital near the Fermi level and facilitates the capturing of protons, just the opposite to the situations for P‐ and S‐coordinated ones. The stable N‐coordinated Pt originates from the kinetic stability throughout the multi‐H‐atom adsorption process. This finding provides a significant guidance for rational design of advanced Pt SSCs on carbon‐based supports.
Activating Interfacial Electron Redistribution in Lattice‐Matched Biphasic Ni3N‐Co3N for Energy‐Efficient Electrocatalytic Hydrogen Production via Coupled Hydrazine Degradation
Authors: Wang Xiaoli , Hu Huashuai , Yan Xiaohui , Zhang Zhaorui , Yang Minghui
Published: March 2024

The development of high‐purity and high‐energy‐density green hydrogen through water electrolysis holds immense promise, but issues such as electrocatalyst costs and power consumption have hampered its practical application. In this study, we present a promising solution to these challenges through the use of a high‐performance bifunctional electrocatalyst for energy‐efficient hydrogen production via coupled hydrazine degradation. The biphasic metal nitrides with highly lattice‐matched structures are deliberately constructed, forming an enhanced local electric field between the electron‐rich Ni3N and electron‐deficient Co3N. Additionally, Mn is introduced as an electric field engine to further activate electron redistribution. Our Mn@Ni3N‐Co3N/NF bifunctional electrocatalyst achieves industrial‐grade current densities of 500 mA cm−2 at 0.49 V without degradation, saving at least 53.3 % energy consumption compared to conventional alkaline water electrolysis. This work will stimulate the further development of metal nitride electrocatalysts and also provide new perspectives on low‐cost hydrogen production and environmental protection.
Solid‐State Photochemical Cascade Process Boosting Smart Ultralong Room‐Temperature Phosphorescence in Bismuth Halides
Authors: Xing Chang , Qi Zhenhong , Zhou Bo , Yan Dongpeng , Fang Wei‐Hai
Published: March 2024

Molecular ultralong room‐temperature phosphorescence (RTP), exhibiting multiple stimuli‐responsive characteristics, has garnered considerable attention due to its potential applications in light‐emitting devices, sensors, and information safety. This work proposes the utilization of photochemical cascade processes (PCCPs) in molecular crystals to design a stepwise smart RTP switch. By harnessing the sequential dynamics of photo‐burst movement (induced by [2+2] photocycloaddition) and photochromism (induced by photogenerated radicals) in a bismuth (Bi)‐based metal‐organic halide (MOH), a continuous and photo‐responsive ultralong RTP can be achieved. Furthermore, utilizing the same Bi‐based MOH, diverse application demonstrations, such as multi‐mode anti‐counterfeiting and information encryption, can be easily implemented. This work thus not only serves as a proof‐of‐concept for the development of solid‐state PCCPs that integrate photosalient effect and photochromism with light‐chemical‐mechanical energy conversion, but also lays the groundwork for designing new Bi‐based MOHs with dynamically responsive ultralong RTP.
Design, synthesis, and biological evaluation of 3‐benzenesulfonamide‐linked 3‐hydrazinoisatin derivatives as carbonic anhydrase inhibitors
Authors: Swain Baijayantimala , Marde Vaibhav S. , Singh Priti , Angeli Andrea , Khan Abrar , Yaddanapudi Venkata M. , Ullah Qasim , Supuran Claudiu T. , Arifuddin Mohammed
Published: March 2024

A new series of isatin‐linked benzenesulfonamide derivatives (9a–w) were synthesized using the tail approach and assayed for their inhibitory potency against four different human carbonic anhydrase (hCA) isoforms, hCA I, II, IX, and XII. Most of these synthesized compounds exhibited interesting inhibition potency against isoforms hCA I, IX, and XII in the nanomolar range and by taking the standard drug acetazolamide. The most potent compounds in the case of hCA I were 9c (435.8 nM) and 9s (956.4 nM), for hCA IX, 9a (60.5 nM), 9d (95.6 nM), 9g (92.1 nM), and 9k (75.4 nM), and for hCA XII, 9p (84.5 nM). However, these compounds showed more selectivity toward hCA IX over hCA I, II, and XII. Thus, these compounds can be further developed as potential lead molecules for the development of isoform‐selective hCA IX inhibitors with further structural modifications.
Design, synthesis, structure elucidation, antimicrobial, molecular docking, and SAR studies of novel urea derivatives bearing tricyclic aromatic hydrocarbon rings
Authors: Sroor Farid M. , El‐Sayed Ahmed F. , Abdelraof Mohamed
Published: March 2024

The targeted compounds were prepared using both (9H‐fluoren‐9‐ylidene)hydrazine (1) and 10H‐phenothiazine (2) as starting materials. The treatment of 1 or 2 with different isocyanates afforded the title compounds 7a–d, 8a, and 8b in excellent yield. All compounds were characterized and ascertained by infrared, nuclear magnetic resonance, and elemental analyses as well as single‐crystal X‐ray diffraction. The antimicrobial efficiency of all was tested in vitro, and a noticeable inhibition activity against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candida albicans was obtained by compounds 7a, 7b, 8a, and 8b. Moreover, the biofilm mechanism activity was strongly inhibited by compounds 7b and 8b for all bacterial pathogens, with a percentage ratio of more than 55%. The findings from the molecular docking simulation revealed that compounds 7a, 7b, 8a, and 8b exhibited favorable binding energies and interacted effectively with the active sites of sterol 14‐demethylase, dihydropteroate synthase, gyrase B, LasR (major transcriptional activator of P. aeruginosa), and carbapenemase for C. albicans, S. aureus, B. subtills, K. pneumoniae, and P. aeruginosa, respectively. These results suggest that the compounds have the potential to inhibit the activity of these enzymes and demonstrate promising antimicrobial properties. Moreover, the in silico evaluation of drug likeness and absorption, distribution, metabolism, excretion, and toxicity (ADMET) profiles for compounds 7a, 7b, 8a, and 8b demonstrated their compatibility with Lipinski's, Ghose's, Veber's, Muegge's, and Egan's rules. These findings suggest that these compounds possess favorable physicochemical properties, making them promising candidates for continued drug development efforts.
Exploring the Diverse Biological Properties of Cannabidiol: A Focus on Plant Growth Stimulation
Authors: Gruľová Daniela , Baranová Beáta , Francolino Rosaria , Elshafie Hazem S. , Kiššová Zuzana , Glovaťáková Alžbeta , De Martino Laura , Amato Giuseppe , Martino Mara , Caputo Lucia , Polito Flavio , Manna Francesco , Camele Ippolito , Tkáčiková Ľudmila , De Feo Vincenzo
Published: March 2024

The aim of the current study was to compare some biological activities of edible oils enriched with 10 % of cannabidiol (CBD samples) from the Slovak market. In addition, hemp, coconut, argan, and pumpkin pure oils were also examined. The study evaluated the fatty acids content, as well as antibacterial, antifungal, antioxidant, cytotoxic, and phytotoxic activities. The CBD samples presented antimicrobial activity against the tested bacterial strains at higher concentrations (10000 and 5000 mg/L) and antifungal activity against Alternaria alternata, Penicillium italicum and Aspergillus flavus. DPPH⋅ and FRAP assays showed greater activity in CBD‐supplemented samples compared to pure oils and vitamin E. In cell lines (IPEC‐J2 and Caco‐2), a reduced cell proliferation and viability were observed after 24 hours of incubation with CBD samples. The oils showed pro‐germinative effects. The tested activities were linked to the presence of CBD in the oils.
Quack‐induced dermatitis: A case report of two dermatitis artefacta induced by quacks advise
Authors: Pudasaini Prajwal , Adhikari Sadiksha , Das Kinnor , Gorai Suraljit , Pamela Ruri D.
Published: March 2024

Key Clinical Message

This report delineates two instances of dermatitis artefacta (DA), a psychodermatological condition marked by self‐induced or exacerbated skin lesions. These cases, triggered by treatments from non‐qualified practitioners, highlight the critical need for healthcare professionals to discern the potential repercussions of unsound medical guidance.