bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expandability of the Covalent Bond: A New Facet Discovered in Extremely Long Csp3-Csp3 Single Bonds
Authors: Ishigaki Yusuke , Uchimura Yasuto , Shimajiri Takuya , Suzuki Takanori 
Published: December 2020

Abstract
Molecules with an extreme structural parameter, such as an elongated C-C bond, have attracted much attention due to their special properties, which ordinary molecules do not have. Stabilized hexaphenylethanes are suitable compounds for seeking for the longest C-C bond. In addition to steric repulsion among the aryl groups (“front strain”) found in 1,1,2,2-tetraarylacenaphthenes (1), “scissor effects” cause expansion of the C1-C2 bond in 1,1,2,2-tetraarylpyracenes (2). A series of crystallographic analyses of 2 revealed that the substituent on the aryl group also affects the C1-C2 bond length. The “front strain” over the weakened bond is enhanced by the ring-fused structure in di(spiroacridan)pyracene (2A). The bond length of 1.771(3) Å determined by X-ray analysis at 93 K is one of the largest values for a Csp3-Csp3 bond, and increases to 1.791(3) Å when the single crystal is heated to 413 K. Further expansion over 1.80 Å was achieved by maximizing the front strain by fixing the spirodibenzocycloheptatriene units in an eclipsed manner in the core-shell-type dihydropyracylene (3B) [1.795(2) Å at 100 K, 1.806(2) Å at 400 K]. Several studies show that “bond expandability” is a newly discovered feature of an elongated covalent bond, which could be used for the future design of novel materials with a mechanical/thermal response.
Enhanced CSPR for a multichannel Kramers–Kronig receiver by self-seeded stimulated Brillouin scattering
Authors: Zhang Honghui , Zhang Qiulin , Xie Qijie , Shu Chester 
Published: December 2020

We demonstrate carrier-to-signal power ratio (CSPR) enhancement by self-seeded stimulated Brillouin scattering to improve the performance of Kramers–Kronig (KK) detection for multichannel single-sideband (SSB) signals. By virtue of low-CSPR transmission and high-CSPR detection, our proposed scheme effectively advances system performance by reducing propagation-induced distortion while maintaining the minimum phase condition. We experimentally demonstrate the improvement in CSPR and bit error rate of

5

×

10

-Gbaud 16-QAM SSB signals by applying the carrier recovery block after 80-km transmission. Under optimum pump power, the average

Q

factor improvement of all five channels is 3.0 dB. We also analyze the performances of different channels and the major limiting factor. The results verify that our scheme offers a promising solution to enhance SSB self-coherent KK detection in wavelength-division multiplexing systems.
Dual-band fiber-chip grating coupler in a 300 mm silicon-on-insulator platform and 193 nm deep-UV lithography
Authors: González-Andrade David , Pérez-Galacho Diego , Montesinos-Ballester Miguel , Le Roux Xavier , Cassan Eric , Marris-Morini Delphine , Cheben Pavel , Vulliet Nathalie , Monfray Stephane , Boeuf Frédéric , Vivien Laurent , Velasco Aitor V. , Alonso-Ramos Carlos 
Published: December 2020

Surface grating couplers are fundamental building blocks for coupling the light between optical fibers and integrated photonic devices. However, the operational bandwidth of conventional grating couplers is intrinsically limited by their wavelength-dependent radiation angle. The few dual-band grating couplers that have been experimentally demonstrated exhibit low coupling efficiencies and rely on complex fabrication processes. Here we demonstrate for the first time, to the best of our knowledge, the realization of an efficient dual-band grating coupler fabricated using 193 nm deep-ultraviolet lithography for 10 Gbit symmetric passive optical networks. The footprint of the device is

17

×

10

µ

m

2

. We measured coupling efficiencies of

−

4.9

and

−

5.2

d
B

with a 3-dB bandwidth of 27 and 56 nm at the wavelengths of 1270 and 1577 nm, corresponding to the upstream and downstream channels, respectively.
10  J operation of a conductive-cooled Yb:YAG active-mirror amplifier and prospects for 100  Hz operation
Authors: Ogino Jumpei , Tokita Shigeki , Kitajima Shotaro , Yoshida Hidetsugu , Li Zhaoyang , Motokoshi Shinji , Morio Noboru , Tsubakimoto Koji , Fujioka Kana , Kodama Ryosuke , Kawanaka Junji 
Published: December 2020

We report, to the best of our knowledge, the highest power conductive-cooled active-mirror amplifier (CcAMA) using Yb:YAG with a pulse energy of 10 J. By using four liquid-nitrogen circulating cooled laser heads, we achieved a repetition rate, pulse energy, and average power of 33.3 Hz, 9.3 J, and 310 W, respectively. The problem of wavefront distortion, which is difficult to solve with a large-aperture active-mirror laser, is suppressed by using reinforcing materials with the same thermal expansion coefficient. We have confirmed that the wavefront distortion is small (

0.15

λ

P-V per head) at 100 Hz operation, which paves the way for 100 Hz operation with the CcAMA concept.
Perceived Consumption of a High-Dose Caffeine Drink Delays Neuromuscular Fatigue
Authors: Elhaj Hussein M. , Imam Osama , Page Brad W. , Vitale Joseph M. , Malek Moh H. 
Published: December 2020

Abstract
Elhaj, HM, Imam, O, Page, BW, Vitale, JM, and Malek, MH. Perceived consumption of a high-dose caffeine drink delays neuromuscular fatigue. J Strength Cond Res 36(5): 1185–1190, 2022—The placebo effect is a concept in which a desired outcome arises, mainly from the belief that the treatment (i.e., supplement or drug) was beneficial although no active ingredient was given. The results of studies related to the placebo effect primarily examine functional performance. What remains unanswered, however, is whether these changes in performance are associated with neuromuscular alterations in the exercised muscles. The purpose of the study, therefore, was to determine the influence of the placebo effect on the physical working capacity fatigue threshold (PWCFT) for a continuous exercise paradigm. To achieve this aim, subjects were told that they were participating in a study to determine the dosage response (low or high) of caffeine on neuromuscular fatigue when in fact no caffeine was given during the experiment. We hypothesized that the perceived consumption of the high-dose caffeine drink would result in a higher PWCFT than the perceived consumption of the low-dose caffeine drink and placebo. Secondarily, we hypothesized that the perceived consumption of the high-dose caffeine drink would result in a higher power output than the perceived consumption of the placebo. Nine healthy college-aged men (mean ± SEM: age, 25.7 ± 1.3 years; body mass, 84.4 ± 3.1 kg; and height: 1.82 ± 0.02 m) volunteered to be in the study. For each of the visits, subjects were given an 8 oz. bottle of water with dissolved crystal light. After the drink was consumed, subjects rested in the laboratory for 1 hour before performing the incremental single-leg knee-extensor ergometry. Immediately after the termination of the incremental single-leg knee-extensor ergometry, the subject was asked which caffeine dose (placebo, low, or high) they believed they consumed for that visit. There were no significant mean differences for maximal power output for the 3 perceived conditions (placebo: 62 ± 3, low-dose caffeine: 62 ± 4, and high-dose caffeine: 65 ± 3 W). When the subjects perceived consuming the high-dose caffeine drink, there were significant mean differences (all p-values < 0.01), for PWCFT, between the other conditions (mean ± SEM: placebo: 23 ± 3 W, low-dose caffeine: 26 ± 2 W, and high-dose caffeine: 42 ± 3 W). This corresponded to a significant mean difference (all p-values < 0.01) when the PWCFT was presented as a percentage of the maximal power output (mean ± SEM: placebo: 37 ± 5%, low-dose caffeine: 42 ± 3%, and high-dose caffeine: 64 ± 3%). The application of our results may indicate that the subject's expectancy, to caffeine consumption, plays a critical role in delaying the onset of neuromuscular fatigue despite not receiving any caffeine in their drinks.
Ensino Embasado na Estrutura Conceitual: a escolha da metodologia ativa para aplicação de casos para ensino importa?
Authors: De Abreu Pontes Gleison , Cardoso Fonseca Kellma Bianca , Caruline Fernandes Ariane , De Souza Costa Patrícia 
Published: December 2020

Objetivo: Identificar quais competências são desenvolvidas na aplicação de casos para ensino com a utilização de técnicas de ensino diferentes, à luz do Ensino Embasado na Estrutura Conceitual (EEEC) e da Taxonomia de Bloom.
Método: Foram testadas três técnicas de ensino: Grupo de Verbalização e de Observação (GVGO), Júri Simulado e Problem-Based Learning (PBL). A percepção dos discentes foi coletada por meio de questionário e grupo focal.
Resultados: Na percepção dos estudantes, o emprego das técnicas, desenvolveu habilidades e competências distintas. Assim, a escolha da metodologia para aplicação de casos deve estar alinhada com os objetivos educacionais estabelecidos pelo docente. Além disso, apesar de terem sido desenvolvidas competências de todos os estágios do EEEC, GVGO e PBL desenvolveram mais aquelas do estágio 3, enquanto o Júri Simulado aquelas do estágio 2.
Contribuições: Os resultados podem ser úteis para o International Accounting Standard Board (IASB) ir além do desenvolvimento de casos para ensino no EEEC, incorporando na agenda reflexões sobre quais metodologias utilizar na aplicação desses materiais no instituto de alcançar o objetivo aplicação coerente das International Financial Reporting Standards (IFRS). Essas reflexões também podem ser realizadas por pesquisadores e docentes a fim de contribuírem com o EEEC.
An assessment of knowledge and practices of breastfeeding among mothers having child less than 2 years of age in a city of central Uttar Pradesh, India
Authors: Kumar Bipul , Bose Tathagata , Das Saurav , Gupta Ashish Kumar , Kumar Ashutosh , Bhandari Ashok 
Published: December 2020

Background: Breastmilk is the natural first food for babies which provides all the energy and nutrients that the infant needs for the first few months of life. More than two thirds of the 2.4 million child deaths occurring each year in India are related to inappropriate infant feeding practices. Initiation of breastfeeding within 1 hour of birth in central Indian states is among the lowest. The situation in central Indian states especially Uttar Pradesh is worse than the rest of India which is usually attributed to prevalent socio-economic and cultural factors.Methods: A cross-sectional descriptive study that was conducted among 144 mothers visiting a tertiary care hospital in Lucknow, Uttar Pradesh, India over a period of nine months using a questionnaire-based interview. Results: The study found that majority of subjects has good knowledge about breastfeeding. 92.4% mothers reported knowledge of putting the baby on the breast within an hour of birth. 65% had the correct breastfeeding position knowledge. Majority were aware that breastfeeding protects from various infections and that colostrum or first milk serves as the first immunization for the baby. 90.3% knew the correct definition of complementary feeding. Most of the subjects planned to breastfeed their baby for a year or more (86.8%). Conclusions: Majority mothers had good knowledge of breastfeeding and complementary feeding and good breastfeeding practices were being followed. This study brought out that educated mothers had better breastfeeding knowledge and practices, thus highlighting to the importance of formal education in mothers.
A clinic-epidemiological study of organophosphorus poisoning in children in a tertiary care medical college hospital
Authors: Anees-ur-Rahman Mohammed , Suresh Karthik , Visweswaraiah Kumar Gowripura , Subbaraya Ananda Kumar Tumkur 
Published: December 2020

Background: Acute organophosphorus (OP) pesticide poisoning is widespread and is the most common poisoning in many developing countries and varies in different geographic regions. Organophosphorus compounds are anti acetyl cholinesterase which exert their toxicity by interfering with the normal function of acetylcholine, an essential neurotransmitter throughout the autonomic and central nervous system.Methods: The present study was conducted in department of pediatrics Sri Siddhartha medical college, Tumkur. All children with OP poisoning admitted in the pediatric ward were included in the study. Unknown compound/tablet poisoning, which was contradictory to the diagnosis of OP compound were excluded.Results: Out of 5,274 cases which were admitted in pediatric ward, 15 children were diagnosed as OP poisoning. In the present study the incidence of OP poisoning was 2.84%. Out of 15 cases 3 cases were below 1 year of age, 2 cases were in the age group of 1-5 years, 5 cases were in the age group of 6-10 years and 5 cases were seen in above 11 years of age. Among 15 cases 13 (86.7%) cases were accidental poisoning and 2 (13.3%) cases were attempt to suicide. Out of 15 cases 4 (26.7%) cases were seen in monsoon, 4 (26.7%) cases were seen in winter and 7 (46.6%) in summer season. Out of 15 cases 14 (93.3%) cases improved with treatment and 1 (6.7%) case discharged against medical advice.Conclusions: Most cases of accidental poisoning are preventable by close watch on the toddlers and younger children who have a habit of tasting unknown things. Educate school children in all aspects of childhood poisoning.
Assessment of knowledge and practice toward infection control and prevention standards among intern doctors in Saudi Arabia
Authors: Albarrag Ahmad M. , Aloraini Abdulmajeed A. , Alhussain Abdulaziz I. , Alwarhi Faris I. , Altashlan Abdullah I. , Alhadi Naif M. 
Published: December 2020

Background: Patients and healthcare workers are susceptible to health care associated infections if they are not compliant with infection prevention and control standards. There are no previous studies regarding the assessment of knowledge and practice of intern doctors toward infection prevention and control precautions in Saudi Arabia.Methods: A cross-sectional study that was carried-out on 259 intern doctors at the main hospitals of Riyadh city in Saudi Arabia. A self-administered questionnaire was distributed to the participants after validation during their clinical rounds and their morning meetings of their departments. Data were analysed using SPSS version 21.0. Results: Out of 259 participants, the overall mean score for knowledge assessment was 79.4±7.52. For hand hygiene mean score was 23.53±2.66 out of 30, personal protective equipment mean score was 20.63±2.49 out of 25. A significant low level of knowledge regarding needle stick injury with a score of 19.18±2.50 out of 30. Regarding, knowledge towards isolation precautions, around 50% reported adequate knowledge regarding isolation precautions. Meanwhile, 78 (30.1%) denied receiving any form of training or orientation in infection control. Conclusions: There is a moderate level of knowledge and satisfactory level of practice among intern doctors in Riyadh. However, there was some misconceptions regarding needle stick injury and isolation precaution. Implementing infection control education and training programs is recommended before starting clinical practice.
Factors associated with successful vaginal birth after cesarean section and its outcome in Asella Referral and Teaching Hospital, Ethiopia
Authors: Girma Hulemenash T. , Mekonnen Hussein , Sendo Endalew G. , Deressa Jembere T. 
Published: December 2020

<p class="abstract"><strong>Background:</strong> Planned vaginal birth after cesarean section is appropriate for and offered to the majority of women with a singleton pregnancy of cephalic presentation at 37 weeks or beyond. The main purpose of the study was to assess factors associated with successful vaginal birth after cesarean section and its outcome in Asella Referral and Teaching Hospital. </p><p class="abstract"><strong>Methods:</strong> An institutional based case-control study conducted to identify factors associated with successful vaginal birth after cesarean section and its outcome in a two years period. The data was collected from patients’ charts after tracing a patient’s number, a double proportion sampling technique was used to determine sample size using EPI info version 7.1.4.0, and multivariate regression analysis of independent variables associated with successful vaginal birth after cesarean section was performed with unmatched case control. </p><p class="abstract"><strong>Results:</strong> Two hundred eighty-eight (288) mothers with history of one previous cesarean delivery attempted vaginal birth after cesarean section. This study found significant successful vaginal birth after cesarean section in mothers with previous vaginal birth, prior successful vaginal delivery after cesarean section, presented with cervical dilatation more than or equal to 4 cm and intact membrane at admission. Meconium&gt;grade I and duration of labour&gt;481minute negatively affected the success rate but weight did not affect vaginal birth after cesarean outcome.</p><p class="abstract"><strong>Conclusions:</strong> Careful selection of mother is the corner stone of successful vaginal birth after cesarean section with special consideration of gestational age, condition of membrane, and develops national evidence-based clinical practice guidelines for potential implication. </p>
Incidence and reasons for leave against medical advice among orthopedic and trauma patients at the university college hospital Ibadan
Authors: Ogunrewo Tolulope O. , Magbagbeola Oluwadayo A. , Oladejo Samuel T. , Allen-Taylor Adeoye 
Published: December 2020

<p><strong>Background:</strong> Leave against medical advice (LAMA) of hospitalized patients is an adverse clinical event in which a patient chooses to leave the hospital before it is medically advisable to do so and it negatively affects the treatment outcome. Because of this, the study was designed to determine the incidence of and indications for LAMA among orthopedic patients who presented at the accident and emergency department of the university college hospital, Ibadan.</p><p><strong>Methods: </strong>This was a prospective hospital-based study determining the incidence of LAMA among orthopedic patients who presented at the accident and emergency department of the university college hospital, Ibadan between September 2019 and March 2020.</p><p><strong>Results: </strong>A total of 289 patients with orthopedic conditions presented within the study period and about 12.46% of these LAMA. The male to female ratio observed in this study is 2:1. The age range was between 8 and 93 years. Trauma from motorbike and motor vehicle accidents accounted for over 80% of the etiology. The most important factor influencing LAMA is financial constraints (63.9%) and LAMA was signed mostly by the patients (25%).</p><p><strong>Conclusions: </strong>LAMA among orthopedic patients in Ibadan is mostly due to financial reasons, therefore, factors that will reduce the cost of management such as the accessibility to health insurance schemes will significantly reduce the incidence of LAMA among orthopedic patients in Nigeria.</p><p> </p>
A comparative study on the functional outcome of intertrochanteric fractures treated by proximal femoral nailing or dynamic hip screw fixation
Authors: Chandy Gineshmon , S. Saju 
Published: December 2020

<p class="abstract"><strong>Background:</strong> Intertrochanteric fractures are one of the commonly occurring injuries in elderly patients and are high among females and those with osteoporosis. They were treated with either dynamic hip screw (DHS) fixation or proximal femoral nailing (PFNA2) here at our institution. The study was conducted in order to find which method of surgical fixation has better functional outcome. </p><p class="abstract"><strong>Methods:</strong> Total 96 patients of intertrochanteric fractures admitted during the study period of November 2017 to April 2019 were included for the study. These patients were randomly divided into two groups; DHS was used as implant in group1 and PFNA2 in group 2. Postoperatively patients were followed up after 1 month, 3months and 6 months of the surgery and were assessed using Harris hip score.<strong></strong></p><p class="abstract"><strong>Results:</strong> Harris hip score was higher with PFNA2 group compared to DHS group in all follow-ups. In unstable fractures DHS group had poor outcome compared to PFNA2. Radiological union occurred in 27.1 % cases by 3 months and 72.9% cases by 6 months with DHS whereas 70.8% and 97.9% respectively with PFNA2. </p><p class="abstract"><strong>Conclusions:</strong> PFNA2 gives a better functional outcome when compared to DHS. Even though DHS gives good functional outcome in stable fractures it is not so in the case of unstable fractures. The radiological union also is faster with proximal femoral nailing. Hence in our opinion PFNA2 can be the better fixation device compared to DHS especially in unstable fractures. </p>
Outcome analysis of solitary osteochondromas of femur managed surgically: a series of 32 patients
Authors: Gupta Sanjeev , Ghani Abdul , Dev Bias , Mahajan Rahul , Mohd John , Singh Amarjeet , Lone Zubair A. 
Published: December 2020

<p class="abstract"><strong>Background:</strong> Osteochondroma is the commonest benign bone tumor in humans. This tumor may either be solitary or present as multiple lesions. Solitary osteochondromas are much more common. Femur is the single most common long bone involved followed by tibia and humerus. Osteochondromas may be either asymptomatic or may present as pain, pressure symptoms or functional impairment. Most of the symptomatic lesions need surgical excision.</p><p class="abstract"><strong>Methods:</strong> This was a prospective study which included 32 patients with solitary osteochondromas of femur, who were managed with surgical excision. Only the symptomatic cases were operated. Minimum follow-up period was 18 months after surgery.<strong></strong></p><p class="abstract"><strong>Results:</strong> This study involved 23 males (71.87%) and nine females (28.12%). 30 osteochondromas (93.75%) were located in the distal femoral metaphysis while as only two cases (6.25%) of proximal metaphyseal involvement were seen. The commonest indication for surgery was pain. Other indications included cosmetic causes, restricted joint movement, fracture of osteochondroma and paresthesia or numbness. The complications included post-operative hematoma formation which was seen in 2 patients (6.25%), infection which was seen in one patient (3.12%), post-operative hypoaesthesia in 2 patients (6.25%) and recurrence of the tumor occurred in one patient (3.12%).</p><p><strong>Conclusions:</strong> Surgical excision of the solitary symptomatic femoral osteochondromas is a rewarding and safe procedure with minimal complications. </p>
Histamine Level in Freshwater and Marine Fish Sold in Bulgarian Markets
Authors: Bangieva D. , Stratev D. , Stoyanchev T. 
Published: December 2020

Background: Histamine is an essential biogenic amine produced as a result of microbial decomposition of histidine during seafood processing and storage. The objective of this study was to evaluate histamine concentration in freshwater and marine fish marketed in Stara Zagora region, Bulgaria.
Methods: Forty fish samples were purchased from local fish farms and retail stores in Stara Zagora, Bulgaria. Enzyme-Linked Immunosorbent Assay was used to determine histamine levels. The data were processed using GraphPad Software InStat 3.
Results: Histamine was detected in 26 out of 40 (65%) samples, and none of them exceeded the regulatory limit of 200 mg/kg. The average histamine content in marine fish (6.965±3.187 mg/kg) was insignificantly (p>0.05) higher than that in freshwater fish (4.503±1.133 mg/kg).
Conclusion: The results reveal low levels of histamine in freshwater and marine fish indicating their good quality. However, its presence in seafoods remains a major food safety problem that requires permanent regulation of histamine concentration in fish.