bluuebunny/crossref_metadata_2025 huggingface dataset:
Una magistratura finanziaria ateniese poco nota: i poristai
Authors: Usai Flavia
Published: June 2024

Abstract A little-known Athenian financial magistracy: the poristai The essay examines the role of the poristai, a financial magistracy that functioned in Athens between the 5th and 4th centuries BC, and to which scholars have devoted scarce attention. The importance that Athens ascribed to the poroi was a central factor in its politics from as early as the 5th century. Management of the Athenian economy underwent a series of substantial changes from the end of the Peloponnesian War onwards, and since the state required increasingly specialized financial management skills, these authorities seem to have played a prominent role. The difficult economic situation that ensued from the Sicilian defeat of 413 had necessitated the creation of this unusual board of magistrates known as the poristai, whose unusual task was most likely that of administering public funds and state revenues. This essay focuses on references to the board in ancient sources, and on the often ‘technical’ use of the verb porizo, in order to shed light on the functions and identity of some of these magistrates, and on the possibility that this initially anomalous office gradually gained a permanent status during the 4th century.
First-principles study on effects of alloying elements Sn and Nb on phase stability of corrosion oxide films of zirconium alloys
Authors: Chen Tun , Cui Jie-Chao , Li Min , Chen Wen , Sun Zhi-Peng , Fu Bao-Qin , Hou Qing ,   Key Laboratory for Radiation Physics and Technology, Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China,   Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu 610200, China
Published: June 2024

Water-side oxidative corrosion of zirconium alloy is a key problem in the design of nuclear fuel rods cladding materials in pressurised water reactors (PWRs), and its corrosion resistance is one of the main factors limiting service life. At present, Zr-Sn-Nb system alloys are still the main development direction of advanced zirconium alloys. Sn and Nb can exhibit a variety of valence states in the oxide film of the cladding and significantly affect the stability of ZrO2. However, the influence mechanism of Sn and Nb on the fraction of t-ZrO2 and the t-m phase transition is unclear. In this work, the lattice properties, formation enthalpies, and oxygen vacancy formation energy of ZrO2 under the doping conditions of Sn and Nb with different valence states are calculated based on the first-principles, and the influence mechanism of Sn and Nb on the stability of ZrO2 is revealed at an atomic scale. The results show that there is a significant difference between the effects of Sn and Nb, as well as between low-valent and high-valent elements. Sn2+ and Nb3+ cause lattice swelling to be significantly distorted , Nb5+ causes lattice to shrink, which contributes to reducing the stresses within the film, and Sn4+ leads the lattice to slightly swell. The low-valent elements all make ZrO2 less stable and are unfavourable for the stability of t-ZrO2 relative to m-ZrO2. The high-valent Nb5+and Sn4+ promote the relative stability of t-ZrO2, thus inhibiting the t-m phase transition, with Nb5+ having a significant effect and Sn4+ having a weak effect. The relative stability of t-ZrO2 increases with pressure rising in a range of 0–3.5 GPa. Compared with high-valent elements, the low-valent elements are favourable for introduing oxygen vacancies into t-ZrO2, thus stabilising the interfacial t-ZrO2 and enhancing the corrosion resistance of the cladding. By investigating the electronic structure, it is found that the oxygen vacancy formation energy is positively correlated with the magnitude of charge transfer (or degree of electron localisation) between the alloying element ion and the oxygen vacancy. These results contribute to optimizing the composition and designing the structure for corrosion resistance of zirconium alloys.
Improved Speed of InterCriteria Analysis
Authors:   Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str. Bl. 105, Sofia 1113 Bulgaria, Marazov Alexander , Shannon Anthony ,   Warrane College University of New South Wale, Kensington NSW 2033, Australia
Published: June 2024

We will show that the computation of the intercriteria counters can be done in O(n log n) time (quasi-linear complexity). Up to this point, all implementations have used O(n2) operations, which does not allow processing of data over hundreds of thousands.
Detection of cyberhate speech towards female sport in the Arabic Xsphere
Authors: Alhayan Fatimah , Almobarak Monerah , Shalabi Hawazen , Alshubaili Luluwah , Albatati Renad , Alqahtani Wafa , Alhaidari Nofe
Published: June 2024

The recent rapid growth in the number of Saudi female athletes and sports enthusiasts’ presence on social media has exposed them to gender-hate speech and discrimination. Hate speech, a harmful worldwide phenomenon, can have severe consequences. Its prevalence in sports has surged alongside the growing influence of social media, with X serving as a prominent platform for the expression of hate speech and discriminatory comments, often targeting women in sports. This research combines two studies that explores online hate speech and gender biases in the context of sports, proposing an automated solution for detecting hate speech targeting women in sports on platforms like X, with a particular focus on Arabic, a challenging domain with limited prior research. In Study 1, semi-structured interviews with 33 Saudi female athletes and sports fans revealed common forms of hate speech, including gender-based derogatory comments, misogyny, and appearance-related discrimination. Building upon the foundations laid by Study 1, Study 2 addresses the pressing need for effective interventions to combat hate speech against women in sports on social media by evaluating machine learning (ML) models for identifying hate speech targeting women in sports in Arabic. A dataset of 7,487 Arabic tweets was collected, annotated, and pre-processed. Term frequency-inverse document frequency (TF-IDF) and part-of-speech (POS) feature extraction techniques were used, and various ML algorithms were trained Random Forest consistently outperformed, achieving accuracy (85% and 84% using TF-IDF and POS, respectively) compared to other methods, demonstrating the effectiveness of both feature sets in identifying Arabic hate speech. The research contribution advances the understanding of online hate targeting Arabic women in sports by identifying various forms of such hate. The systematic creation of a meticulously annotated Arabic hate speech dataset, specifically focused on women’s sports, enhances the dataset’s reliability and provides valuable insights for future research in countering hate speech against women in sports. This dataset forms a strong foundation for developing effective strategies to address online hate within the unique context of women’s sports. The research findings contribute to the ongoing efforts to combat hate speech against women in sports on social media, aligning with the objectives of Saudi Arabia’s Vision 2030 and recognizing the significance of female participation in sports.
β-asarone induces viability and angiogenesis and suppresses apoptosis of human vascular endothelial cells after ischemic stroke by upregulating vascular endothelial growth factor A
Authors: Sun Dazhong , Wu Lulu , Lan Siyuan , Chi Xiangfeng , Wu Zhibing
Published: June 2024

Ischemic stroke (IS) is a disease with a high mortality and disability rate worldwide, and its incidence is increasing per year. Angiogenesis after IS improves blood supply to ischemic areas, accelerating neurological recovery. β-asarone has been reported to exhibit a significant protective effect against hypoxia injury. The ability of β-asarone to improve IS injury by inducing angiogenesis has not been distinctly clarified. The experimental rats were induced with middle cerebral artery occlusion (MCAO), and oxygen-glucose deprivation (OGD) model cells were constructed using human microvascular endothelial cell line (HMEC-1) cells. Cerebral infarction and pathological damage were first determined via triphenyl tetrazolium chloride (TTC) and hematoxylin and eosin (H&E) staining. Then, cell viability, apoptosis, and angiogenesis were assessed by utilizing cell counting kit-8 (CCK-8), flow cytometry, spheroid-based angiogenesis, and tube formation assays in OGD HMEC-1 cells. Besides, angiogenesis and other related proteins were identified with western blot. The study confirms that β-asarone, like nimodipine, can ameliorate cerebral infarction and pathological damage. β-asarone can also upregulate vascular endothelial growth factor A (VEGFA) and endothelial nitric oxide synthase (eNOS) and induce phosphorylation of p38. Besides, the study proves that β-asarone can protect against IS injury by increasing the expression of VEGFA. In vitro experiments affirmed that β-asarone can induce viability and suppress apoptosis in OGD-mediated HMEC-1 cells and promote angiogenesis of OGD HMEC-1 cells by upregulating VEGFA. This establishes the potential for β-asarone to be a latent drug for IS therapy.
Ortaokul Fen Bilimleri Ders Kitaplarındaki İdeolojik Örüntüler
Authors: Ural Ayhan , Özkan Palavaroğlu Sema
Published: June 2024

Bu çalışmanın amacı ortaokul fen bilimleri ders kitaplarındaki enerji kaynakları ve santralleri ile küresel ısınma ve iklim değişikliği konularının anlatımında kullanılan ideolojik örüntüler üzerine bir çözümleme yapmaktır. Nitel araştırma yaklaşımının benimsendiği araştırmada veriler, doküman incelemesi tekniği ile toplanmıştır. Araştırmanın verileri, eleştirel söylem analizi yoluyla sosyo-bilişsel yaklaşım ile çözümlenmiştir. Ulaşılan sonuca göre, enerji kaynakları ve santralleri ile küresel ısınma ve iklim değişikliği konularının anlatımında kullanılan ifadelerde, açık ve/veya örtülü olarak neoliberalizmin etkileri görülmüştür. Ders kitaplarında ele alınan konuların anlatımındaki ifadelerin, kitlesel sorumluluğa sahip olanların eylemlerini bireysel sorumluluğa indirgediği; bireysellik değerlerini ‘iyi’ bir tüketici ve serbest piyasa odaklı bir vatandaş temelinde ele aldığı belirlenmiştir. Ayrıca ders kitaplarındaki ifadelerin bireysel sorumlulukları ve standartlaşma gibi değerleri vurguladığı; toplumsal duyarlılık, toplumsal fayda, karşılıklılık ve etik değerlere yer vermediği, toplulukçu unsurları barındırmadığı görülmüştür. Ortaokul fen bilimleri ders kitapları, çevre sorunlarına yer vermesi ve/veya çözüm önerileri ile göstergebilimsel açıdan çevreci bir kurguyla inşa edilmiştir. Elde edilen sonuçlar ortaokul fen bilimleri ders kitaplarının çevreye duyarlı ve yararlı unsurları işaret ettiğinin altını çizse de kurgu boyutunda anılan kitapların küresel sermaye ve onun geleneksel dinamikleri etrafında şekillendiğini özellikle eleştirel pedagoji bağlamında özgürleşmeye yeterli katkıda bulunamadığını göstermektedir. Araştırma sonuçlarından hareketle fen bilimleri ders kitaplarında yer alan ve toplumun genelini ilgilendiren içerikler, sosyal, politik, kültürel ve tarihsel yapılar öğrencilerin yaş, bilgi ve deneyimleri bağlamı ile daha yakın ilişkilendirilebilir. Sonuç olarak ortaokul fen bilimleri ders kitaplarında, özellikle toplumun genelini ilgilendiren konularda, öğrencilerin kendi yaşanmışlıklarını ortaya koyabilecekleri alanlar yaratan; “özgürleştirici” bir pedagojiye yer verilmesi önerilebilir.
A Case of Paraganglioma as an Unusual Tenant of Gallbladder
Authors: Hingway Snehlata , Naseri Suhit , Gadkari Pravin
Published: June 2024

Gallbladder paraganglioma is an exceptionally uncommon tumour. Paragangliomas are a subset of Neuroendocrine Neoplasms (NENs) called neurogenic NENs that arise from neural crest cells of the neuroectoderm. They present diagnostic challenges due to their uncommon occurrence and non specific clinical manifestations. The paraganglion system consists of two cell types, called chief and sustentacular cells. The most common location of a paraganglioma is the adrenal medulla, defined as pheochromocytoma. Pheochromocytomas, found in the adrenal medulla, are known for their high Catecholamine (CA) production, leading to significant clinical manifestations like hypertension and metabolic disturbances. A 36-year-old female, otherwise asymptomatic, underwent cholecystectomy due to persistent abdominal discomfort in the right hypochondrium for two months. Preoperative imaging demonstrated a gallstone. Laparoscopic cholecystectomy was performed. The pathological analysis following surgery documented the presence of gallbladder paraganglioma and chronic cholecystitis. Immunohistochemically, chief cells displayed widespread positivity for chromogranin, synaptophysin, and sustentacular cells displayed S100 positivity. There are no definitive guidelines for the management of gallbladder paragangliomas due to their rarity. Reporting instances of paraganglioma in the gallbladder is critical to raising clinical awareness, enhancing diagnostic criteria, optimising treatment protocols, and unravelling the underlying molecular mechanisms. All of these efforts are critical for improving patient care and outcomes in treating this uncommon and enigmatic tumour entity.
Morphometric Anatomy of Atlas (C1) and Axis (C2) on Dry Bones Versus CT Scan Images: A Cross-sectional Study from Southern India
Authors: Periyasamy Vinodhini , Deepa KS , Mythilikrishnan R , Kishore G Krishna , Anupama D
Published: June 2024

Introduction: The uniqueness of the atlas (C1) and axis (C2) cervical vertebrae helps in transmitting weight from the cranial cavity to the rest of the vertebral column. A detailed understanding of the C1 and C2 morphometric dimensions is essential for evaluating treatment protocols such as screw placement and intralaminar fixations to provide stability for the occipitocervical complex. Computerised Tomography (CT) scan images are best for demonstrating the osseous margins. Aim: To assess the relationship between the linear morphometric measurements of the CT images and dry C1 and C2 vertebrae. Materials and Methods: A descriptive, cross-sectional study was conducted using 35 atlas (C1) and 35 axis (C2) dry bones from the Department of Anatomy, Karuna Institute of Medical Sciences, Palakkad, Kerala, India, from August 2023 to October 2023. A total of 35 CT scan images were also taken for the study. Siemens Syngo software tool was utilised to assess the C1 and C2 vertebrae. Measurements of the vertebral canal, foramen transversarium, superior articular facets, vertebral artery groove, dens, and body were performed on dry C1, C2, and CT images. Descriptive statistics were evaluated using mean, standard deviation, percentage difference, and mean deviation. The unpaired t-test was used to test significance, with p-value <0.05 considered statistically significant. Results: Concerning the anatomical parameters, between the dry C1 and CT scan images, all linear parameters were statistically significant (p-value <0.05), except for the vertebral artery groove-inner and outer distances, which were not statistically significant. Regarding C2, when comparing anatomical parameters between dry vertebrae and CT scan images, the width of the body and the length of the vertebral canal were not statistically significant, while all other C2 parameters were statistically significant (p-value <0.05). Conclusion: The results obtained from the study on the atlas and axis may be valuable for operating surgeons during surgical procedures in the craniovertebral region. The present study also aids in preventing iatrogenic complications, including vertebral neurovascular injuries, and provides a roadmap for skilled surgical access.
Socio-Economic Profile of KVK Staff and Farmers for Utilization of ICT Tools in Central Uttar Pradesh, India
Authors: Dube Ritesh , Kumar Sheelesh , Singh Shani Kumar
Published: June 2024

The study was conducted in Central Uttar Pradesh to know the socio-economic characteristics of KVK staff and farmers. Kanpur Dehat, Unnao, Lucknow, Rae Bareli and Pratapgarh districts were selected purposively because these districts are nearer to Lucknow. The respondents selected for the study include 37 KVK staff from 5 KVKs and 175 farmers from 5 villages of 5 districts. The study's findings revealed that the majority of KVK staff (65%) were aged between 35 to 47 years, 78 per cent were male and 70 per cent were belonging to the general category. 74 per cent of KVK staff hold doctorate degrees and 70 per cent were Subject Matter Specialists. Moreover, 62 per cent had 6-15 years of work experience, 68 per cent had an annual income between 6-10 lakhs, and 52 per cent had ICT training. Among the farmers, 60 per cent were between 31 to 47 years old, and 77 per cent were male. Half of (50%) the farmers belonged to the SC/ST category, and about one-third (31%) had educational qualifications up to the intermediate level. Nearly half (46%) lived in mixed houses, while 72 per cent lived in joint families with 74 per cent having large family sizes. 35 per cent had land holdings up to 2.5 acres, 93 per cent engaged in farming as their occupation and 50 per cent had an annual income between 1-2 lakhs. Additionally, 48 per cent held membership in one organization. For information purposes, the majority of farmers used computers/laptops (63%), farm magazines (61%), and newspapers (60%). For entertainment, (48%) used the radio and 37 per cent watched TV.
The Association between Depression, Daytime Sleepiness, Chronotype and Fatigue among the Students
Authors: Soni Nishi , Jaiswal Saurabh , Kumar Sudhir , Malik Shalie , Rani Sangeeta
Published: June 2024

Fatigue and excessive daytime sleepiness (EDS) are frequently conflated in everyday life, but they are separate concepts with distinct symptoms. Despite their potential to coexist or occur independently, their interplay with depression remains largely unexplored. This study investigates the complex relationship between fatigue, excessive daytime sleepiness (EDS), and depression among students, aiming to unravel their relative associations. A cross-sectional survey of Indian school students (N=450) aged 11 to 20 (15.2±1.46) was analysed. The study used self-reported measures such as the Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), and the Center for Epidemiologic Studies Depression Scale (CES-D). The findings revealed significant associations between depression and various combinations of sleepiness and fatigue, with the E+F+ group showing the strongest correlation. Depression was significantly higher in excessive daytime sleepers (N= 165, 69.9%) (P < 0.001) and fatigue (N= 167, 70.8%) (p < 0.001). Depression was found positively correlated with fatigue (r =0.332, p < 0.001 and daytime sleepiness (r=0.213, p<0.001). Chronotype was found negatively correlated with fatigue (r=-0.124, p<0.001), daytime sleepiness (r=-0.105, p<0.05), and depression (r=-0.198, p<0.001). These findings underscore a significant association (p<0.001) between depression and the presence of both excessive daytime sleepiness and fatigue. This revelation demands a nuanced approach to mental health interventions, recognizing the shared underlying mechanisms and advocating for comprehensive strategies that address these intertwined facets of student well-being.
A Rare Tumorous Presentation of Endobronchial Tuberculosis: Clinical Insights and Case Analysis
Authors: Nakarani Rushita D. , Chopra R.K.
Published: June 2024

Endobronchial tuberculosis (EBTB) is a rare manifestation of pulmonary tuberculosis characterized by bronchial inflammation, often presenting with tumor-like masses in the airways. Misdiagnosis, particularly as lung cancer or bronchial asthma, is common due to its atypical presentation. We present a case of a 38-year-old female with persistent cough, wheezing, and constitutional symptoms, initially misdiagnosed with community-acquired pneumonia. Despite broad-spectrum antibiotics, there was no improvement. Imaging revealed right upper lobe collapse and a suspicious lesion, prompting a PET-CT scan that indicated a neoplastic or infectious etiology. Bronchoscopy confirmed a friable growth in the right main bronchus, with subsequent biopsy and bronchoalveolar lavage revealing Mycobacterium tuberculosis. Prompt initiation of anti-tuberculosis therapy led to symptom resolution. This case underscores the importance of considering tuberculosis in patients with persistent respiratory symptoms, even without prior TB history.
Políticas culturais emergenciais na pandemia da COVID-19? Demandas e estratégias de enfrentamento e as respostas dos poderes públicos
Authors: Canedo Daniele Pereira , Andrade Carlos Magno Diniz Guerra de , De Freitas Elizabeth Ponte , Campos Luiz Gustavo Santana , Carvalho Rosimeri
Published: June 2024

A vulnerabilidade da economia criativa, que antecede a crise sanitária de 2020, tem tornado o contexto da pandemia ainda mais impactante para os segmentos artísticos, culturais e criativos. A paralisação das atividades não fez discriminação: afetou formais e informais; empreendimentos criativos de grande e pequeno porte; organizações e artistas que atuam em todas as etapas da cadeia produtiva: na produção, na distribuição e no consumo. Diante do contexto de crise, a atuação dos poderes públicos através da elaboração de políticas culturais emergenciais tem sido demandada pelos agentes do setor. Este artigo apresenta recursos, necessidades, e estratégias de enfrentamento apontadas pelos respondentes da pesquisa “Impactos da  COVID-19 na Economia Criativa”, propondo reflexões sobre as primeiras respostas dos poderes públicos.
High Thermoelectric Efficiency of n‐type PbS
Authors: Wang Heng , Schechtel Eugen , Pei Yanzhong , Snyder G. Jeffrey
Published: November 2012

PbS shares several features with the other lead chalcogenides PbX (X: Te, Se), which are good thermoelectric materials. PbS has a potential advantage in that it is quite earth abundant and inexpensive. In this work we tune the transport properties in n‐type, single‐phase polycrystalline PbS1‐xClx (x ≤ 0.008) with different carrier densities. Lead chloride provides a nearly 100% efficient doping control up to 1.2 × 1020 cm−3. The maximum zT achieved at 850 K is 0.7 with a predicted zT ∼ 1 at 1000 K. This is about twice as high as what was previously reported (∼0.4) for binary PbS. Compared with the other lead chalcogenides the higher effective mass and higher lattice thermal conductivity makes binary PbS an inferior thermoelectric material. However this study also predicts greater potential of zT improvement in PbS by material engineering such as alloying or nanostructuring compared to PbSe or PbTe. Considering their abundance and low cost, PbS based materials are quite competitive among the lead chalcogenides for thermoelectric applications.
Growth and weight status of rural Texas school youth
Authors: Duran Mary , Gillespie Joe , Malina Robert M. , Little Bertis B.
Published: November 2012

Context:

Evidence indicates higher prevalence of obesity in rural American youth. The present study evaluates the growth status and estimates the prevalence of overweight and obesity among rural school children in Texas.

Methods:

Heights and weights were measured in a sample of 1,084 school youth (545 males, 539 females) 5–19 years of age, in rural north central Texas in 2010. body mass index (BMI) was calculated. Growth status was plotted relative to US reference data. Weight status (underweight/thin, overweight, and obesity) was classified relative to age‐ and sex‐specific Centers for Disease Control (CDC) and International Obesity Task Force (IOTF) criteria. Concordance of classifications was evaluated.

Results:

Mean heights of the rural children approximated reference medians, while median weights exceeded reference medians and approximated 75th percentiles with increasing age. Median BMIs of boys and girls were below the 75th percentiles except among late adolescent girls. Prevalence of underweight/thinness was low (<4%). Overweight approximated 20% among boys 6–11 years and 16% among boys 12–19 years with CDC criteria; the opposite was apparent for obesity, 6–11 years, 16%, and 12–19 years, 20%. Approximately, equal percentages of boys in both age groups were classified overweight (∼21–22%) with IOTF criteria, but almost twice as many older (15%) than younger (8%) boys were classified obese. Overweight was less prevalent (∼5%) but obesity more prevalent (∼5%) with CDC compared to IOTF criteria, but both were less prevalent among younger than older girls.

Conclusion:

Prevalence of overweight and obesity among rural Texas school youth was comparable to national estimates for 2007–2008. The results highlight a need for programs aimed at preventing unhealthy weight gain and/or weight reduction given the tendency of obesity to track from childhood into adulthood and potentially negative health consequences of obesity. Am. J. Hum. Biol., 2013. © 2012 Wiley Periodicals, Inc.
Upregulation of Bcl‐2 in nasal polyps from patients with cystic fibrosis
Authors: Scapa Victor I. , Ramakrishnan Vijay R. , Kingdom Todd T.
Published: November 2012

Background

Nasal polyps in patients with cystic fibrosis (CF) are believed to be phenotypically different than polyps affecting non‐CF patients. The aim of this study was to investigate differences in cell cycle regulatory mechanisms between these 2 groups. In this prospective study at a tertiary care academic medical center, multiple techniques were used to confirm the upregulation of antiapoptotic Bcl‐2 family proteins in CF polyps.

Methods

Nasal polyps were prospectively obtained from CF and non‐CF patients. The Sigma Panorama Protein Microarray for Cell Signaling was used to identify differences in protein expression between the 2 polyp groups. Western blot analysis confirmed altered expression of a subset of these proteins. Immunohistochemical staining was performed on archived tissue to further investigate B‐cell lymphoma 2 protein (Bcl‐2) expression. Following review by a pathologist, slides were digitized using an Aperio™ ScanScope XT system and staining intensity was quantified with the Positive Pixel Count algorithm. The mean staining intensity for each polyp group was compared.

Results

The protein microarray suggested a greater than 2‐fold upregulation of Bcl‐xl in CF polyps relative to non‐CF polyps. Western blot analysis confirmed the upregulation in CF polyps of Bcl‐2, a more commonly studied protein analog of Bcl‐xl. The CF polyp group was noted to have a higher quantitative intensity of immunohistochemical staining for Bcl‐2 compared to the non‐CF group (p < 0.05).

Conclusion

Through multiple modalities of protein investigation, we have demonstrated an upregulation of Bcl‐2 family proteins in CF polyps relative to polyps from non‐CF patients.
Risk factors and outcomes for primary, revision, and modified Lothrop (Draf III) frontal sinus surgery
Authors: Naidoo Yuresh , Bassiouni Ahmed , Keen Mark , Wormald Peter‐John
Published: November 2012

Background

The purpose of this level 4, retrospective cohort study was to detail the outcomes of primary, revision, and endoscopic modified Lothrop procedure (EMLP) (Draf III) frontal sinus surgery and evaluate whether risk factors would help determine which patients would benefit from which procedures.

Methods

The study used a retrospective chart review. Endoscopic assessment of frontal ostium patency and patient reported symptoms were prospectively collected on patients who underwent frontal sinusotomy between January 2003 and December 2009. High‐risk cohorts were studied to assess their response to standard endoscopic sinus surgery (ESS) compared with EMLP.

Results

A total of 339 patients who met the inclusion and exclusion criteria underwent either primary or revision endoscopic frontal sinus surgery. The average ± standard deviation (SD) length of follow‐up was 20.8 ± 18.7 (95% confidence interval [CI], 18.0–22.9) months. Postsurgical recurrence of disease with persistence of symptoms requiring an EMLP occurred in 9 patients in the primary group and 38 in the revision group. The highest risk groups for failure of standard frontal sinusotomy were patients with nasal polyps, asthma, Lund‐Mackay score >16, and frontal ostium size <4 mm (relative risk = 9.9, p < 0.0001).

Conclusion

Patients with underlying asthma and polyposis as well as narrow frontal ostia and extensive radiological disease have a high failure rate from standard endoscopic frontal sinusotomy. In this patient group consideration should be given to offering the patient a primary EMLP procedure, which has excellent success rates with low risks and low morbidity.
Photochemical Evidence of Electronic Interwall Communication in Double‐Wall Carbon Nanotubes
Authors: Vizuete María , Gómez‐Escalonilla María J. , García‐Rodriguez Sergio , Fierro José Luis G. , Atienzar Pedro , García Hermenegildo , Langa Fernando
Published: November 2012

Single‐ and double‐wall carbon nanotubes (CNTs) having dimethylanilino (DMA) units covalently attached to the external graphene wall have been prepared by the reaction of the dimethylaminophenylnitronium ion with the corresponding CNT. The samples have been characterized by Raman and XPS spectroscopies, thermogravimetry, and high‐resolution transmission electron microscopy in which the integrity of the single or double wall of the CNT and the percentage of substitution (one dimethylanilino group every 45 carbons of the wall for the single‐ and double‐wall samples) has been determined. Nanosecond laser flash photolysis has shown the generation of transients that has been derived from the charge transfer between the dimethylanilino (as the electron donor) to the CNT graphene wall (as the electron acceptor). Importantly, the lifetime of the double‐wall CNT is much shorter than that monitored for the single‐wall CNT. Shorter‐lived transients were also observed for the pentyl‐esterified functionalized double‐wall CNT with respect to the single‐wall analogue in the presence of hole (CH3OH) and electron quenchers (O2, N2O), which has led to the conclusion that the inner, intact graphene wall that is present in double‐wall CNT increases the charge mobility significantly, favoring charge recombination processes. Considering the importance that charge mobility has in microelectronics, our finding suggests that double‐wall CNT or two‐layer graphene may be more appropriate to develop devices needing fast charge mobility.
A Chiral Self‐Assembled Monolayer Derived from a Resolving Agent and its Performance as a Crystallization Template for an Organic Compound from Organic Solvents
Authors: Bejarano‐Villafuerte Ángela , van der Meijden Maarten W. , Lingenfelder Magalí , Wurst Klaus , Kellogg Richard M. , Amabilino David B.
Published: November 2012

A new chiral nonracemic thiol derived from a popular acidic resolving agent that incorporates a cyclic disubstituted phosphate group (phencyphos) has been prepared in enantiomerically pure form. The stereochemistry and absolute configuration were established by performing a single‐crystal X‐ray structural analysis of a synthetic intermediate. The thiol compound was used for the preparation of self‐assembled monolayers (SAMs) on both monocrystalline and polycrystalline metallic gold, which have very different surface roughness. The monolayers were used to promote the nucleation and growth of crystals from nonaqueous solutions of an organic molecule (the parent phencyphos) of similar structure to the compound present in the monolayer. The template layers influence the nucleation and growth of the phencyphos crystals despite the lack of two‐dimensional order in the surfaces. Heterogeneous nucleation of phencyphos takes place upon evaporation of either CHCl3 or isopropanol solutions of the compound on the SAM surfaces, where the evaporation rate merely influences the size and homogeneity of the crystals. The roughness of the surface also plays an important role; the polycrystalline gold produces more homogeneous samples because of the greater number of nucleation sites. Clear evidence for nucleation and growth on the surfaces is shown by scanning electron microscopy. The variation in crystal form achieved by using different surfaces and solvents suggests that the layers are applicable for the preparation of organic crystals from organic solutions.
New Liquid Crystalline Materials Based on Two Generations of Dendronised Cyclophosphazenes
Authors: Jiménez Josefina , Laguna Antonio , Gascón Elena , Sanz José Antonio , Serrano José Luis , Barberá Joaquín , Oriol Luis
Published: November 2012

A divergent approach was used for the synthesis of dendritic structures based on a cyclotriphosphazene core with 12 or 24 hydroxyl groups, by starting from [N3P3(OC6H4OH‐4)6] and using an acetal‐protected 2,2‐di(hydroxymethyl)propionic anhydride as the acylating agent. Hydroxyl groups in these first‐ and second‐generation dendrimers, G1‐(OH)12 or G2‐(OH)24, were then condensed in turn with mono‐ or polycatenar pro‐mesogenic acids to study their ability to promote self‐assembly into liquid crystalline structures. Reactions were monitored by using 31P{1H} and 1H NMR spectroscopy and the chemical structure of the resulting materials was confirmed by using different spectroscopic techniques and mass spectrometry (MALDI‐TOF MS). The results were in accordance with monodisperse, fully functionalised cyclotriphosphazene dendrimers. Thermal and liquid crystalline properties were studied by using optical microscopy, differential scanning calorimetry and X‐ray diffraction. The dendrimer with 12 4‐pentylbiphenyl mesogenic units gives rise to columnar rectangular organisation, whereas the one with 24 pentylbiphenyl units does not exhibit mesomorphic behaviour. In the case of materials that contain polycatenar pro‐mesogenic units with two aromatic rings (A4 vs. A5), the incorporation of a short flexible spacer connected to the periphery of the dendron (acid A5) was needed to achieve mesomorphic organisation. In this case, both dendrimer generations G1 A5 and G2 A5 exhibit a hexagonal columnar mesophase.
Chirality of Anisotropic Metal Nanowires with a Distinct Multihelix
Authors: Xie Junjie , Che Shunai
Published: November 2012

Two‐dimensional (2D) anisotropic silver nanowire (AgNW) arrays, fabricated inside chiral mesoporous silica (CMS), exhibited strong and tunable plasmon circular dichroism (CD) signals in the visible and near‐IR regions due to collective dipole coupling between the anisotropic AgNWs. The multihelix with a helical channel orientation and helical arrays of opposite handedness in CMS played a predominant effects on the transversal and longitudinal chirality of the AgNWs, respectively.This behavior differs from both isotropic‐nanoparticle and single‐helix‐induced CD responses. This system will provide new insight into the optical activity of metal inorganic nanoparticles capped with chiral organic molecules and assembled in chiral environments.
Spiroketal‐Based Phosphorus Ligands for Highly Regioselective Hydroformylation of Terminal and Internal Olefins
Authors: Jia Xiaofei , Wang Zheng , Xia Chungu , Ding Kuiling
Published: November 2012

A new class of bidentate phosphoramidite ligands, based on a spiroketal backbone, has been developed for the rhodium‐catalyzed hydroformylation reactions. A range of short‐ and long‐chain olefins, were found amenable to the protocol, affording high catalytic activity and excellent regioselectivity for the linear aldehydes. Under the optimized reaction conditions, a turnover number (TON) of up to 2.3×104 and linear to branched ratio (l/b) of up to 174.4 were obtained in the RhI‐catalyzed hydroformylation of terminal olefins. Remarkably, the catalysts were also found to be efficient in the isomerization–hydroformylation of some internal olefins, to regioselectively afford the linear aldehydes with TON values of up to 2.0×104 and l/b ratios in the range of 23.4–30.6. X‐ray crystallographic analysis revealed the cis coordination of the ligand in the precatalyst [Rh(3 d)(acac)], whereas NMR and IR studies on the catalytically active hydride complex [HRh(CO)2(3 d)] suggested an eq–eq coordination of the ligand in the species.
Q‐learning for estimating optimal dynamic treatment rules from observational data
Authors: Moodie Erica E. M. , Chakraborty Bibhas , Kramer Michael S.
Published: November 2012

The area of dynamic treatment regimes (DTR) aims to make inference about adaptive, multistage decision‐making in clinical practice. A DTR is a set of decision rules, one per interval of treatment, where each decision is a function of treatment and covariate history that returns a recommended treatment. Q‐learning is a popular method from the reinforcement learning literature that has recently been applied to estimate DTRs. While, in principle, Q‐learning can be used for both randomized and observational data, the focus in the literature thus far has been exclusively on the randomized treatment setting. We extend the method to incorporate measured confounding covariates, using direct adjustment and a variety of propensity score approaches. The methods are examined under various settings including non‐regular scenarios. We illustrate the methods in examining the effect of breastfeeding on vocabulary testing, based on data from the Promotion of Breastfeeding Intervention Trial. The Canadian Journal of Statistics 40: 629–645; 2012 © 2012 Statistical Society of Canada
Variable selection and estimation in generalized linear models with the seamless ${\it L}_{{\rm 0}}$ penalty
Authors: Li Zilin , Wang Sijian , Lin Xihong
Published: November 2012

In this paper, we propose variable selection and estimation in generalized linear models using the seamless $L_0$ (SELO) penalized likelihood approach. The SELO penalty is a smooth function that very closely resembles the discontinuous $L_0$ penalty. We develop an efficient algorithm to fit the model, and show that the SELO‐GLM procedure has the oracle property in the presence of a diverging number of variables. We propose a Bayesian information criterion (BIC) to select the tuning parameter. We show that under some regularity conditions, the proposed SELO‐GLM/BIC procedure consistently selects the true model. We perform simulation studies to evaluate the finite sample performance of the proposed methods. Our simulation studies show that the proposed SELO‐GLM procedure has a better finite sample performance than several existing methods, especially when the number of variables is large and the signals are weak. We apply the SELO‐GLM to analyze a breast cancer genetic dataset to identify the SNPs that are associated with breast cancer risk. The Canadian Journal of Statistics 40: 745–769; 2012 © 2012 Statistical Society of Canada
A black‐box decomposition approach for coupling heterogeneous components in hemodynamics simulations
Authors: Blanco Pablo J. , Leiva Jorge S. , Buscaglia Gustavo C.
Published: November 2012

This work presents a generic and efficient black‐box approach for the strong iterative coupling of dimensionally heterogeneous flow models in computational hemodynamics. A heterogeneous model of the cardiovascular system is formed by several vascular black‐box components, which are connected through coupling equations. The associated system of equations is solved using the Broyden algorithm. In addition, a multiple time‐stepping strategy is introduced to meet different component requirements. The proposed algorithm is employed to split a 3D–1D–0D closed‐loop model of the cardiovascular system into corresponding black‐box components standing for the 3D (specific vessels), 1D (systemic arteries/peripheral vessels), and 0D (venous/cardiac/pulmonary circulation) components. Examples of application are presented showing the robustness and suitability of this novel approach. Copyright © 2012 John Wiley & Sons, Ltd.
Reproduction of pressure field in ultrasonic‐measurement‐integrated simulation of blood flow
Authors: Funamoto Kenichi , Hayase Toshiyuki
Published: November 2012

Ultrasonic‐measurement‐integrated (UMI) simulation of blood flow is used to analyze the velocity and pressure fields by applying feedback signals of artificial body forces based on differences of Doppler velocities between ultrasonic measurement and numerical simulation. Previous studies have revealed that UMI simulation accurately reproduces the velocity field of a target blood flow, but that the reproducibility of the pressure field is not necessarily satisfactory. In the present study, the reproduction of the pressure field by UMI simulation was investigated. The effect of feedback on the pressure field was first examined by theoretical analysis, and a pressure compensation method was devised. When the divergence of the feedback force vector was not zero, it influenced the pressure field in the UMI simulation while improving the computational accuracy of the velocity field. Hence, the correct pressure was estimated by adding pressure compensation to remove the deteriorating effect of the feedback. A numerical experiment was conducted dealing with the reproduction of a synthetic three‐dimensional steady flow in a thoracic aneurysm to validate results of the theoretical analysis and the proposed pressure compensation method. The ability of the UMI simulation to reproduce the pressure field deteriorated with a large feedback gain. However, by properly compensating the effects of the feedback signals on the pressure, the error in the pressure field was reduced, exhibiting improvement of the computational accuracy. It is thus concluded that the UMI simulation with pressure compensation allows for the reproduction of both velocity and pressure fields of blood flow. Copyright © 2012 John Wiley & Sons, Ltd.
A buffer management algorithm for improving up/down transmission congestion protocol fairness in IEEE 802.11 wireless local area networks
Authors: Huang Jiawei , Wang Jianxin , Ye Jin
Published: November 2012

The fair allocation of the resources is an important issue in wireless local area network (WLAN) because all wireless nodes compete for the same wireless radio channel. When uplink and downlink transmission congestion protocol (TCP) flows coexist in WLAN, the network service is biased toward the uplink TCP flows, and the downlink TCP flows tend to starve. In this article, we investigate the special up/down TCP unfairness problem and point out that the direct cause is the uplink acknowledgement (ACK) packets occupy most buffer space of access point. We thus propose a buffer management algorithm to ensure the fairness among uplink and downlink TCP flows. In order to limit the greedy behavior of ACK packets, the proposed algorithm adjusts the maximum size of buffer allocated for the ACK packets. Analysis and simulation results show that the proposed solution not only provides the fairness but also achieves 10–20% lower queue delay and higher network goodput than the other solutions. Copyright © 2012 John Wiley & Sons, Ltd.
E‐cadherin interactions are required for Langerhans cell differentiation
Authors: Mayumi Nobuko , Watanabe Eri , Norose Yoshihiko , Watari Eiji , Kawana Seiji , Geijtenbeek Teunis B. H. , Takahashi Hidemi
Published: November 2012

Human skin contains the following two distinct DC subsets: (i) Langerhans cells (LCs), expressing Langerin but not DC‐specific intercellular adhesion molecule‐3‐grabbing nonintegrin (DC‐SIGN), are predominantly localized in the epidermis; and (ii) dermal DCs, expressing DC‐SIGN but not Langerin, are observed mainly in the dermis. It is not known whether localization in the epidermis provides cues for LC differentiation. Here, we show that E‐cadherin expressed by epidermal keratinocytes (KCs) is crucial for differentiation of LCs. Monocytes differentiated into LC‐like cells in presence of IL‐4, GM‐CSF, and TGF‐β1. However, these LC‐like cells expressed not only Langerin but also DC‐SIGN. Notably, co‐culturing of these LC‐like cells with KCs expressing E‐cadherin or recombinant E‐cadherin strongly decreased expression of DC‐SIGN and further induced a phenotype similar to purified epidermal LCs. Moreover, pretreatment of LC‐like cells with anti‐E‐cadherin‐specific antibody completely abolished their Langerin expression, indicating the requirement of E‐cadherin–E‐cadherin interactions for the differentiation into Langerin+ cells. These findings suggest that E‐cadherin expressed by KCs provide environmental cues that induce differentiation of LCs in the epidermis.
Functionalized N‐Heterocyclic Carbene Ligands for Dual Enantioselective Control in the Cu‐Catalyzed Conjugate Addition of Dialkylzinc Compounds to Acyclic Enones
Authors: Dohi Kenta , Kondo Junko , Yamada Haruka , Arakawa Ryuichi , Sakaguchi Satoshi
Published: November 2012

A series of highly tunable, functionalized azolium compounds have been synthesized from chiral α‐amino acid derivatives such as β‐amino alcohols or α‐amino esters. The combination of a Cu salt and a chiral azolium efficiently facilitated the asymmetric conjugate addition (ACA) reactions of acyclic enones with dialkylzinc under ambient conditions without temperature control. Of the (hydroxy amide)‐functionalized azolium ligand precursors, which were derived from β‐amino alcohols, an azolium salt containing a tert‐butyl group as the stereodirecting group was found to be the best choice of ligand. Ligand screening revealed that the use of an azolium salt containing a sterically bulky alkyl substituent such as N‐CHRR′ on the azolium ring led to a marked increase in the enantioselectivity of the ACA reaction. Thus, a new efficient (hydroxy amide)‐functionalized azolium ligand precursor such as 26, which was prepared from 1‐(diphenylmethyl)benzimidazole and (S)‐tert‐leucinol, has been developed. The treatment of benzalacetone (30) with Et2Zn in the presence of catalytic amounts of [Cu(OTf)]2(C6H6) and 26 at room temperature gave the corresponding 1,4‐adduct 31 with excellent enantioselectivity (92 % ee). On the other hand, the enantioselectivity of the ACA reactions of acyclic enones with dialkylzinc was successfully reversed by the use of (ester amide)‐functionalized azolium salts, which were obtained from α‐amino esters. Several functionalized azolium ligand precursors from readily available serine esters have been designed and synthesized. Finally, it was found that 30 could react with Et2Zn under the influence of a bis(hexafluoroacetylacetonato)copper(II) salt and C2‐symmetric azolium salt 36 to afford ent‐31 in almost quantitative yield with 89 % ee. A plausible reaction mechanism for the switching of the stereoselectivity in the ACA reaction by these two functionalized azolium compounds is described.
21st century climate change: where has all the geomorphology gone?
Authors: Lane Stuart N.
Published: November 2012

This Commentary draws together recently published work relating to the relationship between climate change and geomorphology to address the surprising observation that geomorphic work seems to have had little impact upon the work of the Intergovernmental Panel for Climate Change. However, recent papers show that methodological innovation has allowed geomorphological reconstruction over timescales highly relevant to late 20th century and 21st century climate change. In turn, these and other developments are allowing links to be made between climatic variability and geomorphology, to begin to predict ‘geomorphic futures’ and also to appreciate the role that geomorphic processes play in the flux of carbon and the carbon cycle. Copyright © 2012 John Wiley & Sons, Ltd.