Evaluation of the root morphology of mandibular first premolars using cone-beam computed tomography in a peruvian population / Evaluación de la morfología radicular de primeros premolares mandibulares mediante tomografía computarizada de haz cónico en una población peruana

Introduction: The morphology of the root canal of the first premolars is not always the same and therefore a good knowledge of its dental anatomy is essential. Aim: To assess the morphology of roots and root canals of mandibular first premolars in a Peruvian population using cone-beam computed tomography (CBCT). Materials and Methods: This was a descriptive cross-sec-tional study. A total of 370 mandibular first premolars fulfilling the inclusion criteria were evaluated using CBCT, and the number of roots and root canals, the Vertucci's classification of root canal configuration, age, sex and side of the tooth were registered. Results: One and two roots were presented in 96.2% (n=356) and 3.8% (n=14), respectively, of the mandibular first premolars analyzed, and one canal was present in 67.6% (n=250) and two canals in 32.2% (n=119). A type I root canal configuration was found in 67.6% (n=250) of the cases followed by type V with 26.2% (n=97). A statistically significant association was found between the number of roots and canals (p<0.001) and age also had a significant influence on this variable (p=0.0043). Conclusions: The presence of one canal in mandibular first premolars is the most frequent, although there is a considerable prevalence of two in the population studied. The number of roots is associated with the number of canals, with age having a significant influence on these variables.

Introducción: La morfología del canal radicular de los primeros premolares no siempre es la misma y por ello es fundamental un buen conocimiento de su anatomía dental. Objetivo: Evaluar la morfología de las raíces y conductos radiculares de primeros premolares mandibulares en una población peruana mediante tomografía computarizada de haz cónico. Materiales y Métodos: Este fue un estudio transversal descriptivo. Se evaluaron mediante tomografías un total de 370 primeros premolares mandibulares que cumplían con los criterios de inclusión, y se registró el número de raíces y conductos radiculares, la clasificación de Vertucci de la configuración radicular, la edad, el sexo y el lado del diente. Se realizaron las pruebas de chi-cuadrado y una regresión logística binaria (p<0,05). Resultado: Se presentó una y dos raíces en el 96,2% (n=356) y 3,8% (n=14), respectivamente, de los primeros premolares mandibulares analizados, y un canal estuvo presente en el 67,6% (n=250) y dos canales en el 32,2% (n=119). Se encontró una configuración del conducto radicular tipo I en el 67,6% (n=250) de los casos seguido del tipo V con un 26,2% (n=97). Se encontró una asociación estadísticamente significativa entre el número de raíces y conductos (p<0.001) y la edad también influyó significativamente en esta variable (p=0.0043). Conclusión: La presencia de 1 canal en primeros premolares mandibulares es la más frecuente, aunque existe una prevalencia considerable de 2 en la población estudiada. El número de raíces está asociado al número de canales, teniendo la edad una influencia significativa en estas variables.

Morphology of the Second Mesiobuccal Canal in the Maxillary Second Molar / Morfología del Segundo Canal Mesiovestibular en el Segundo Molar Maxilar

SUMMARY: Failure to locate a complete canal system affects the prognosis of root canal treatment. A missed root canal is one of the most common reasons for failed root canal treatment. The prevalence of the second mesiobuccal canal in the maxillary second molar is relatively high and has a variety of configurations. Therefore, knowledge of its morphology is required in clinical endodontics. This review presented the canal in terms of its prevalence, classification, anatomical features, and the method for locating the second mesiobuccal canal in the maxillary second molar. Root canal treatment requires knowledge of tooth morphology, appropriate access preparation, and a thorough examination of the tooth's interior. Thus, clinicians should carefully employ various methods for assessing the anatomy of the entire root canal system to prevent failure in locating the second mesiobuccal canal. This canal can be located by modifying the access cavity design and utilizing specific instruments to improve the second mesiobuccal canal system visualization.

La falta de localización de un sistema completo de canal afecta el pronóstico del tratamiento de éste. La omisión de un tratamiento de canal es uno de los motivos más frecuentes por las que el tratamiento de canal fracasa. La prevalencia del segundo canal mesiovestibular en el segundo molar superior es relativamente alta y tiene una variedad de configuraciones. Por tanto, el conocimiento de su morfología es necesario en endodoncia clínica. Esta revisión presentó el canal en términos de su prevalencia, clasificación, características anatómicas y el método para localizar el segundo canal mesiovestibular en el segundo molar superior. El tratamiento de canal requiere conocimiento de la morfología del diente, una preparación adecuada del acceso y un examen exhaustivo del interior del diente. Por lo tanto, los dentistas deben emplear cuidadosamente varios métodos para evaluar la anatomía de todo el sistema de canales radiculares para evitar fallas en la localización del segundo canal mesiovestibular. Este canal se puede localizar modificando el diseño de la cavidad de acceso y utilizando instrumentos específicos para mejorar la visualización del sistema del segundo canal mesiovestibular.

Microcomputed-Tomographic Analysis of the Root Canal Morphology of the Mandibular First Molars in a Malaysian Subpopulation Using Two Classification Systems / Análisis por Tomografía Microcomputada de la Morfología del Conducto Radicular de los Primeros Molares Mandibulares en una Subpoblación de Malasia Utilizando dos Sistemas de Clasificación

SUMMARY: This work investigated the morphology of the root canal system of the mandibular first molar in a Malaysian subpopulation. Using micro-computed tomography with an isotropic resolution of 22 µm, 140 mandibular first molars were scanned. MIMICS software was used for segmentation, 3-D reconstruction and analysis of the acquired images. The canal configuration was described using Vertucci [supported by the supplementary configurations proposed by Sert & Bayirli (2004)] and Ahmed et al. (2027), coding systems. The chi-square test was used to assess the association between qualitative variables. By non-considering intercanal communications, Vertucci types IV (17.1%) and I (76.4%) were the most frequently reported configurations in the mesial and distal roots, respectively. Of the reported configurations, 24.3% and 4.3% were non-classifiable by Vertucci system in the mesial and distal roots, respectively. Up to 63.6% and 9.3% of the reported configurations were non- classifiable, and type I was the most frequent when considering intercanal communications (7.1% and 76.4% in the mesial and distal roots, respectively). According to Ahmed et al., system, almost half of the sample had more than four digits (47.9%), followed by the 3-digits category (20.71%). In both systems, a significant association was found between the canal configuration and the root type (p<0.001). The mandibular first molar of this Malaysian subpopulation demonstrated a wide range of root canal morphology. When compared to the Vertucci system, the system developed by Ahmed et al., successfully classified all molars configurations despite their level of complexity. The complex canal anatomy of mandibular first molars in this subpopulation warrants special attention during root canal treatment procedures.

En este trabajo se investigó la morfología del sistema de conductos radiculares del primer molar mandibular en una subpoblación de Malasia. Utilizando tomografía microcomputada con una resolución isotrópica de 22 µm, se escanearon 140 primeros molares mandibulares. Se utilizó el software MIMICS para segmentar (enmascarar), reconstruir en 3D, visualizar y analizar las imágenes adquiridas. La configuración del canal se describió utilizando Vertucci respaldado por las configuraciones complementarias propuestas por Sert & Bayirli (2004)] y Ahmed et al. (2017, 2020), sistemas de codificación. Se utilizó la prueba de chi-cuadrado para evaluar la asociación entre variables cualitativas. Sin considerar las comunicaciones intercanales, los tipos Vertucci IV (17,1%) y I (76,4%) fueron las configuraciones reportadas con mayor frecuencia en las raíces mesiales y distales, respectivamente. De las configuraciones reportadas, el 24,3 % y el 4,3 % fueron no clasificables por el sistema de Vertucci en las raíces mesial y distal, respectivamente. Hasta el 63,6 % y el 9,3 % de las configuraciones reportadas fueron no clasificables, siendo la tipo I la más frecuente al considerar las comunicaciones intercanales (7,1 % y 76,4 % en las raíces mesiales y distales, respectivamente). Según Ahmed et al. (2017, 2020) en el sistema, casi la mitad de la muestra tenía más de cuatro dígitos (47,9 %), seguido por la categoría de 3 dígitos (20,71 %). En ambos sistemas se encontró una asociación significativa entre la configuración del canal y el tipo de raíz (p<0,001). El primer molar mandibular de esta subpoblación de Malasia demostró una amplia gama morfológica del conducto radicular. En comparación con el sistema Vertucci, el sistema desarrollado por Ahmed et al. (2017, 2020) clasificaron con éxito todas las configuraciones de los molares a pesar de su nivel de complejidad. La compleja anatomía del canal de los primeros molares mandibulares en esta subpoblación merece una atención especial durante los procedimientos de tratamiento de conducto.

Discussion on Disease Mechanism of Autism Spectrum Disorders from the Concepts of “Vital Activity” and “Qi Configuration” / 中医杂志

This paper　explored the disease mechanism of autism spectrum disorders （ASD） from the perspectives of “vital activity” and “qi configuration”， and it is believed that “vital activity” represents the internal regulatory mechanisms of the human body， while “qi configuration” represents the ability of the body to communicate and adapt to the external environment. Abnormal genetic factors lead to the extinction of vital activity in children with ASD， resulting in increased susceptibility to ASD. Environmental instability leads to the solitary qi configuration in ASD， triggering and exacerbating the manifestations of ASD on the basis of genetic susceptibility. In addition， epigenetic mechanisms also play an important role in the pathogenesis of ASD. Imbalances in vital activity and disruptions in qi configuration result in failure in qi transformation of zang-fu organs， with abnormal symptoms manifested through the five orifices. It is proposed that the treatment of ASD should aim to achieve a harmonious interaction between “vital activity” and “qi configuration” to accelerate the recovery of affected children.

Exploration on the Paths of Traditional Chinese Medicine Constitution Intervention to Improve the Quality of Life：Based on the Perspective of Configuration / 中医杂志

ObjectiveTo adapt to the dynamic multidimensional changes in traditional Chinese medicine （TCM） constitution， the paths of improving the quality of life through TCM constitution intervention are proposed from a configuration perspective. MethodsFive hundred and nine subjects were included in the study， all of whom voluntarily participated in and completed TCM constitution interventions， and completed 60-item Constitution in Chinese Medicine Questionnaire （CCMQ） （including 9 subscales： neutral type， qi deficient type， yang deficient type， yin deficient type， phlegm-dampness type， damp-heat type， blood stasis type， qi stagnation type， and special constitution type） to evaluate the TCM constitution， and the Short Form Health Questionnaire （SF-36） in Chinese version （including overall， physical component scores （PCS）， and mental component scores （MCS）） before and 6 months after the intervention to evaluate the quality of life. The necessary condition analysis （NCA） and fuzzy set qualitative comparative analysis （fsQCA） were used to explore the necessary conditions and advantage configurations for improving the overall， physical and mental quality of life of TCM constitution dimension changes. ResultsThe results of NCA showed that the changes in the scores of neutral type and qi stagnation type can serve as necessary conditions for improving the SF-36 overall quality of life scores （P＜0.05）. The changes in the scores of neutral type and blood stasis type can serve as necessary conditions for improving PCS scores. The changes in scores of the other 7 types can serve as necessary conditions for improving MCS scores. The fsQCA results showed that the necessary consistency of a change in a particular physical subscale score alone did not reach to a necessary condition for a change in SF-36 total score， PCS score， and MCS score （consistency ＜ 0.9 for all）， so the results of NCA were considered. The results of configuration analysis found that 6 configurations were included in increasing the overall quality of life scores and PCS scores， and 7 in increasing the MCS scores， with overall consistency ＞ 0.7. Improving the overall quality of life scores required a focus on lowering the qi deficient type scores， or reducing the yang deficient type scores while increasing the neutral type scores； reducing the scores of phlegm-dampness type and qi stagnation type is beneficial for improving the PCS scores； increasing the neutral type scores and reducing the scores of deficient type， yang deficient type， phlegm-dampness type， and stagnation type is beneficial for increasing MCS scores. ConclusionTCM constitution interventions can improve physical， mental and overall quality of life， and its improvement in the mental domain of quality of life is closely related to the paths of overall quality of life. In order to improve the quality of life， in addition to increasing the tendency of the neutral type， more focused and targeted measures should also be taken to decrease the degrees of qi deficient type， yang deficient type， qi stagnation type， and phlegm-dampness type.

Finite element analysis of different fixation methods of partially threaded cannulated screws for treating vertical femoral neck fractures / 中国组织工程研究

BACKGROUND:The more vertical the femoral neck fracture line,the more shear force the femoral neck fracture may bear,so it may be prone to internal fixation failure,nonunion,or necrosis of the femoral head.At present,there is controversy as to which hollow nail fixation mode is ideal. OBJECTIVE:To evaluate different configurations and numbers of cannulated screw configurations to learn more about the biomechanical differences in vertical fractures of the femoral neck using finite element analysis. METHODS:Femoral CT data were collected from a 24-year-old healthy male volunteer and imported into Mimics software to build a three-dimensional geometric model of the femur.Model refinement and surface fitting processing were carried out in Geomagic software and imported into SolidWorks software to establish a vertical fracture model of the femoral neck.Six cannulated screw models were established,including three triangle configuration,three inverted triangle configuration,three double-plane double-support configuration(F scheme),three transverse configuration,four diamond configuration and four Alpha configuration.The peak stress,strain and displacement of internal fixation and femoral fracture models under different loads(350,700,1 400,and 2 100 N)were compared among different configurations. RESULTS AND CONCLUSION:(1)Under four kinds of loads,screw stress conditions were as follows:biplanar double-supported configuration(F scheme)>transverse configuration>inverted triangle configuration>positive triangular configuration>Alpha configuration>rhombus configuration.The peak value of Von mises stress was concentrated in the screw close to the fracture line.(2)Under four kinds of loads,the screw displacement was Alpha configuration>inverted triangle configuration>positive triangular configuration>biplanar double-supported configuration(F scheme)>rhombus configuration>transverse configuration,and the peak displacement was mainly concentrated on the hollow screw head.(3)Under four kinds of loads,the stress conditions of the proximal femoral bone block were biplanar double-supported configuration(F scheme)>transverse configuration>inverted triangle configuration>Alpha configuration>positive triangular configuration>rhombus configuration,and the stress peak mainly concentrated in the lower neck of femur.(4)Under 350 N load,the displacement of the proximal femur bone block was transverse configuration>biplanar double-supported configuration(F scheme)>positive triangular configuration>Alpha configuration>inverted triangle configuration>rhombus configuration.In the other three loads,the peak displacement of the inverted triangle configuration was smaller than that of the rhombus configuration.The peak displacement was mainly concentrated in the head.(5)The rhombus configuration was the most dispersed in the stress distribution of the proximal femoral bone.The rhombus configuration was the smallest in the peak displacement of the femur.The stress,displacement and peak displacement of the fracture end of each internal fixed model increased gradually with the increase of load.(6)The biomechanical performance of the four diamond-shaped models in the internal fixation of vertical femoral neck fractures is better than that of other groups of models.The four rhomboid models have stable fixation,small displacement value of fracture end and dispersed stress,which can help resist shear force and prevent varus collapse and create a good mechanical environment for fracture healing.

Numerical simulation of effect of vegetation configuration on human thermal comfort / 环境与职业医学

Background The urban heat island effect has a significant negative impact on human health. Urban green space can effectively improve the urban thermal environment while enhancing human thermal comfort. Objective To investigate the effects of vegetation configuration structure on temperature and humidity and on human thermal comfort, with a view to providing reference for the landscape planning of urban reserve, preventing and reducing the impact of urban heat island effect on the health of urban residents. Methods The study was carried out on a typical clear and cloudless summer day without extreme weather in a university reserve area in Hefei. The numerical simulation accuracy of ENVI-met software was verified by measured data. Based on the quantitative definition of vegetation configuration structure scheme from vertical and horizontal perspectives, nine simulation scenarios were established based on three aspects including vegetation configuration type (grass, shrub + grass, tree + grass, tree + shrub + grass), planting layout (column planting, uniform spot planting), and planting density [the aspect ratio of trees (ART) between plants was 0.75, 1.13, 1.50, and 2.25, respectively] to quantitatively evaluate the cooling and humidifying effects and human thermal comfort [physiological equivalent temperature (PET)] of the vegetation configurations. Results The change trends of the cooling and humidifying effects of all the simulated scenarios were consistent, basically first increasing and then decreasing. Among all the simulated scenarios, the cooling and humidifying effects of scenario 8 (tree + grass, ART=2.25, uniform spot planting) were the best, with the greatest cooling of 1.36 ℃ and humidification of 6.29% in comparison to the worst scenario 1 in the reserve area. The human thermal comfort of scenario 9 (tree + shrub + grass, ART=2.25, uniform spot planting) was the best, with the PET of 35.37 ℃. The order of improvement effect of different vegetation configurations on thermal comfort from strong to weak was tree + shrub + grass structure (scenario 9) > tree + grass structure (scenario 8) > shrub + grass structure (scenario 2) > grass structure (scenario 1). At 15:00, the PET value of tree + shrub + grass structure (scenario 9) decreased by 7.44 ℃ in comparison to that of grass structure (scenario 1). The higher the planting density among trees, the higher the difference in temperature and relative humidity between the simulated and the original scenarios. In case of holding the same amount of greenery, uniform spot planting showed better human comfort when the vegetation was planted sparsely, but the difference between the PET value of scenario 3 (tree + grass, ART=0.75, uniform spot planting) and scenario 5 (tree + grass, ART=1.5, column planting) was only 0.15 ℃; when the vegetation was planted densely, column planting was more favorable to wind circulation and more effective in reducing the temperature of the site, with a lower PET value of 0.87 ℃ for scenario 7 (tree + grass, ART=2.25, column planting) than for scenario 4 (tree + grass, ART=1.13, uniform spot planting). Conclusion Urban green space has obvious cooling and humidifying effects in summer. The human comfort of tree + shrub + grass structure with uniform spot planting is optimal, and the cooling and humidifying effects of tree + grass structure with uniform spot planting are the most obvious. The optimization of vegetation configuration structure is crucial for reducing urban heat island, improving human thermal comfort, and promoting residents’ health.

Configuration and type-selection of PET/CT and PET/MR equipment during the period of National 14th Five-Year Plan / 中国医学装备

Objective:To explore the configuration conditions and type-selections of positron emission tomography/computed tomography(PET/CT)and positron emission tomography/magnetic resonance(PET/MR)system under the national new policies during the 14th Five-Year Plan period,so as to provide references for configuration and type-selection of PET/CT and PET/MR equipment of medical institutions.Methods:According to the management polices of relevant configurations of PET/CT and PET/MR,which included configuration licensing,use management and configuration plan,and which were issued by China 14th Five-Year Plan,as well as the development trend and characteristics of PET/CT and PET/MR new techniques,the configuration conditions and type-selection plan of PET/CT and PET/MR equipment were analyzed.Results:Under the new polices during national 14th Five-Year Plan,medical institutions should configure PET/CT and PET/MR depended on the condition of institutions,personnel condition,work basis,the supporting facilities and other conditions,and should select the type of PET/CT and PET/MR which can meet the requirements of medical institutions depended on the technique parameters and performance indicators of PET/CT and PET/MR.Conclusions:Since the 14th Five-Year Plan,there were significant changes in the new policies related to the configurations of PET/CT and PET/MR compared to previous policies.The medical institutions should apply configurations and use PET/CT and PET/MR as new requirement,and configure the PET/CT and PET/MR equipment and conduct type-selection of them as various requirements of each institution.

Analysis of discipline construction of tumor radiotherapy in non-public hospitals in Zhejiang province / 中华放射肿瘤学杂志

Objective:To investigate the radiotherapy discipline construction and existing problems in non-public hospitals in Zhejiang province and put forward suggestions for improvement.Methods:In 2022, on-site inspection and investigation were carried out in 14 non-public hospitals in Zhejiang province, including equipment configuration and source, discipline setting, personnel qualification and professional experience, academic leaders and admission of patients, etc. Results:For 14 non-public hospitals in Zhejiang province, 19 treatment equipment, 15 positioning equipment and 77 quality control equipment were equipped, and a total of 249 radiotherapy practitioners were employed. A total of 4 224 patients were admitted throught 2022.Conclusion:Multiple problems exist in non-public radiotherapy hospitals in Zhejiang province, such as unscientific discipline setting, fewer professionals, lack of personnel training, unclear management mode, unqualified qualification of partial radiotherapy doctors, and insufficient refinement of clinical quality management, which need to be further improved.

Evaluation of number of configured monitors based on BP neural network / 医疗卫生装备

Objective To evaluate the rationality of the number of configured monitors based on error back propagation(BP)neural network.Methods A BP neural network model was established with the number of the equipment in use as the output result and the average number of inpatients,the average number of operations,the average days of hospitalization,the number of scrapped equipment,the average age of equipment and times of equipment maintenance as the input indicators.The data of 9 internal medicine departments in the whole year of 2020-2021 and the first 2 quarters of 2022 were collected on a quarterly basis as the training set,and the data of the third quarter of 2022 was used as the test set to verify the learning results.The performance of the model was analyzed using the root mean square error,mean absolute error and coefficient of determination.Results The model established behaved well in prediction with the root mean square error between the predicted and expected values of the model being 1.135 7,the mean absolute error being 0.893 72 and the coefficient of determination being 0.958 71.Conclusion The BP neural network-based evaluation is feasible for the number of configured monitors,and guidance is provided for the optimized configuration of the equipment.[Chinese Medical Equipment Journal,2023,44(9):14-18]

MANDIBULAR PREMOLAR WITH TWO ROOTS AND TWO ROOT CANALS: A CASE REPORT.

For the success of a root canal treatment, an in-depth knowledge of pulpal anatomy and its variations are essential. Failure to perform thorough debridement and improper obturation will lead to reinfection of the root canal, which will adversely affect the treatment outcome. Mandibular premolars usually have single root with single root canal system. Howeveranatomic variations of mandibular premolar have been reported. The clinician should be aware of the configuration of the pulp system for the successful endodontic treatment. The incidence of two roots in these teeth is quite rare. This report presents the clinical management of mandibular premolar having two roots bifurcated at the mid-root level

An Assessment of 3.5mm Reconstruction Plate Fixation in Olecranon Fractures

Background: Olecranon process is a large, curved eminence comprising of the proximal and posterior part of the ulna. It lies subcutaneously which makes it more vulnerable to injury. Due to intra-articular extension of fractures, anatomical reduction and early mobilization should be achieved in every case and usually managed surgically. Aims and Objectives: To access the results of reconstruction plate in fracture olecranon.Materials &Methods: This was a prospective study consisted of 25 cases of olecranon fractures which were managed by open reduction and internal fixation using 3.5mm reconstruction plate. Patients were followed up every month till 6 months. At each follow up visit clinical and radiological parameters were assessed: Final assessment was done at 6 months using the Mayo Elbow Performance Score.Result: According to the AO classification, Type A-1 � 7 cases, A-3 � 1case, B-1 � 13 cases, B-3 � 1 case, C-1 � 1 case, C-2 � 1 case, C-3 � 1 case. An adequate reduction was maintained in all fractured olecranon until union. Average radiological union time was 12 weeks in 72% cases, 15 weeks in 16% cases, 18 weeks in 8% cases and > 18 weeks in 4% cases. The results were graded as per the criteria laid by Rogers et al as excellent in 84% cases, good in 12% and unsatisfactory in 4% cases. 2 cases developed superficial infection and 1 deep infection and 1 delayed union.Conclusion: Open reduction and internal fixation of fracture of olecranon with 3.5mm reconstruction plate is based on sound biomechanical principle with a good functional outcome and a low incidence of complications

Discussion on automated external defibrillator configuration optimization strategy of rapidly developing city: a case study of Bao'an, Shenzhen / 中华危重病急救医学

Objective:To explore the automated external defibrillator (AED) configuration optimization strategy in line with the characteristics of the rapidly developing cities by analyzing the actual coverage of AED in Bao'an District based on the real world data of out-of-hospital cardiac arrest (OHCA) in Bao'an District, Shenzhen City.Methods:The data of cardiac arrest database registered in Bao'an District of Shenzhen City from March 1, 2019 to February 29, 2020 were included in a retrospective observational study. The AED coverage of public and non-public areas was analyzed by calculating the minimum distance between the occurrence place of each OHCA event and the nearest AED. The minimum distance ≤100 m was set as AED coverage, and the minimum distance > 100 m was set as non-AED coverage. It was assumed that one AED was configured for each OHCA hotspot area, then the AED coverage changes were analyzed. Based on the actual situation that the AED in schools, governments, sports venues, subways, tourist attractions and parks of public areas in Bao'an District could not be obtained at any time within 24 hours, it was assumed that all AED in the public areas could be obtained at any time within 24 hours, the impact of AED available at any time on AED coverage was analyzed.Results:A total of 525 cases of OHCA were enrolled. The highest incidence of OHCA was found in residential and industrial areas [54.5% (286/525) and 14.3% (75/525), respectively]. There were 252 AED in Bao'an District, Shenzhen, and 115 OHCA events occurred within the coverage area of AED. Even if all AED met the ideal state that could be obtained at any time within 24 hours, the coverage rate was only 21.9% (115/525). The AED coverage rate of the public areas and non-public areas was 31.6% (37/117) and 19.1% (78/408) respectively, with uneven distribution, and the AED coverage rate of non-public areas was low. Assuming that the residential community and industrial zone with more than 2 OHCA cases were respectively equipped with one AED, the coverage rate of AED in the non-public areas increased from 19.1% (78/408) to 28.2% (115/408), basically meeting the requirement that AED could be obtained at any time when OHCA events occurred. Some AED in the public areas of Bao'an District were not available at any time within 24 hours. If the ideal state that all AED in the public area could be obtained at any time within 24 hours could be achieved, the AED coverage rate of all regions increased from 16.8% (88/525) to 21.9% (115/525), the AED coverage rate of the public areas increased from 29.1% (34/117) to 31.6% (37/117), the AED coverage rate of the non-public areas increased from 13.2% (54/408) to 19.1% (78/408).Conclusions:AED configuration in Bao'an District was unevenly distributed, and the coverage rate of AED in non-public areas was low. The allocation strategy for AED in fast-growing cities like Shenzhen should be as follows: on the premise of ensuring AED availability for 24 hours, priority should be given to covering the number of AED in the non-public areas including residential communities and industrial zones; AED is available in the public areas for 24 hours.

A novel sesquiterpenoid from Curcuma longa L / 药学学报

A new compound was isolated from the 95% ethanolic extract of the rhizomes of Curcuma longa L. using silica gel column chromatography, medium pressure liquid chromatography, and semi-preparative high performance liquid chromatography. The structure and absolute configuration of the compound was elucidated by HR-ESI-MS, NMR, and electronic circular dichroism (ECD) calculations. It is a novel sesquiterpenoid, which is named as isoturmeronol B (1). The carbon skeleton of compound 1 is similar to that of bisabolane-type sesquiterpenoid. The only difference is that the methyl group at C-4 in bisabolene-type sesquiterpenoid is migrated to C-5 in compound 1. Besides, the anti-inflammatory and antioxidant activities of the compound 1 were evaluated. The results showed that 1 has no anti-inflammatory and antioxidant activities.

A new anisotane-type sesquiterpene from Anisodus tanguticus / 药学学报

To investigate the chemical constituents of Anisodus tanguticus, silica gel column chromatography, Sephadex LH-20 column chromatography, preparative thin layer chromatography, and semi-preparative HPLC were used to separate and purify the chemical constituents from the extract of A. tanguticus. The planar structure of the isolated compound was identified by HRMS, IR, and 2D NMR experiments. The absolute configuration of the isolated compound was determined by a combination of NOESY, coupling constant, circular dichroism (CD), and transition metal chelate reagent dimolybdenum tetraacetate [Mo2(OAc)4]-induced circular dichroism (ICD) data analysis. A new compound of the anisotane-type sesquiterpene (1) was isolated, which was determined to be (1R,2S,3R,4R,6R,7R,9R)-anisotane-11(13)-ene-3,4,9-triol and named anisotanol F. This is the second report of anisotane-type sesquiterpene, which has previously been reported as a novel sesquiterpenoid skeleton by our research group. Furthermore, the cytotoxicity against HUVECs and inhibitory effect on NO release in LPS-induced RAW264.7 cells of compound 1 were investigated. However, the results showed that it was inactive. Compound 1 is a new compound isolated from A. tanguticus. It belongs to the unusual anisotane-type sesquiterpene. This result enriches the chemical composition of A. tanguticus.

Configuration and the safe use of standardized parenteral nutrient solution for preterm infants / 中国新生儿科杂志

Objective:To study the configuration and safety of standardized parenteral nutrition solution for premature infants.Methods:A retrospective cohort study was used to the premature infants who were admitted to the neonatal intensive care unit of the West China Second Hospital within 24 hours after birth, 28~34 weeks gestational age, and began parenteral nutrition within 48 hours after birth from June 2015 to November 2018. Electrolytes, blood sugar, phlebitis and venous catheter-related infection during the use of parenteral nutrient fluids were collected, and divided into standardized parenteral nutrient solution group and individualized parenteral nutrient solution group according to the types of parenteral nutrient fluids used. Data analysis is realized by using EmpowerStats statistical software based on R language.Results:A total of 840 premature infants were collected, among them, 541 cases of standardized parenteral nutrition solution group and 299 cases of individual parenteral nutrition solution group. Compared with the individual parenteral nutrition solution group, the incidence of hyperglycemia was 6.3% (34/541) vs. 21.7% (65/299), OR=0.491, 95% CI 0.268~0.899. The incidence of hypokalemia was 13.5% (73/541) vs. 59.9% (179/299), OR=0.137, 95% CI 0.090~0.208. The incidence of hypercalcemia was 25.9% (140/541) vs. 62.8% (188/299), OR=0.249, 95% CI 0.162~0.383. The incidence of hypophosphatemia was 0.2% (1/541) vs. 2.7% (8/299), OR=0.076, 95% CI 0.008~0.686. All the differences were statistically significant ( P<0.05) .There was no significant difference in the incidence of catheter-related infections between the two groups ( P>0.05). Conclusions:Standardized parenteral nutrition is safer in maintaining blood glucose, blood potassium and calcium and phosphorus metabolism in premature infants.

Root anatomy and canal configuration of maxillary premolars: a cone-beam computed tomography study / Anatomía de la raíz y configuración del conducto de los premolares maxilares: estudio de tomografía computarizada de haz cónico

SUMMARY: The aim of the study was to determine the number and anatomical configuration of roots and root canals of maxillary first and second premolars using cone-beam computed tomography scans. n273 CBCT scans were evaluated, obtaining a sample of 592 maxillary premolars. Root number and root canal anatomy were categorized using Ahmed´s classification. Data was analyzed using Pearson's Chi-squared test. Two roots were present on 157 first premolars, one root in 132 premolars and three roots in 17. Second premolars presented one root in 266 samples and two roots in 20; no second premolars presented three roots. Eight different configurations were found; the most frequent was 2MP B1 P1 in first premolars (51,3 %) and 1MP1 (63.6 %) in second premolars. The most frequent morphology found in maxillary premolars in Chilean population was two and three roots. The analysis of internal anatomy using CBCT revealed a highly variable distribution of root canals, generally of low to medium complexity, similar to what is found in other ethnic groups.

RESUMEN: El objetivo de este estudio fue determinar el número y la configuración de raíces y canales radiculares de primeros y segundos premolares maxilares utilizado tomografía computacional de haz cónico. 273 TCHC fueron evaluados, obtenido una muestra de 592 premolares maxilares. El número de raíces y la anatomía de los canales radiculares fueron categorizados utilizando la clasificación de Ahmed. Los datos fueron analizados con la prueba Chi- Cuadrado de Pearson. Dos raíces fueron observadas en 157 primeros presentaron una raíz en 266 muestras y dos raíces en 20; no se encontraron tres raíces en segundos premolares. Ocho diferentes configuraciones fueron encontradas; siendo la más frecuente 2MP B1 P1 en primeros premolares (51,3 %) y 1MP1 (63,6 %) en segundos premolares. La morfología radicular más frecuentemente encontrada en premolares de población Chilena fue de dos y tres raíces. El análisis de la anatomía interna usando TCHC mostró una gran variabilidad de en la distribución de los canales radiculares. Generalmente de mediana y baja complejidad como los encontrados en otros grupos etnicos.

Current status and progress of foreign research on nursing human resource allocation system RAFAELA / 中国实用护理杂志

Due to the reform of medical system, sudden infectious diseases and the increasing demand of patients, the problems of insufficient allocation of human resources and low quality of nursing human resources in China not only affect the treatment and prognosis of patients, but also hinder the development of nursing itself. In order to improve the current situation of nursing staffing in China, this paper summarizes the RAFAELA system of nursing resource allocation in Finland and the need for improvement. In order to promote the improvement and development of the optimal allocation of nursing human resources in China.

Analysis on the changing trend of nursing human resources in China from 1990 to 2019 / 中华医院管理杂志

Objective:To clarify the long-term trend of nursing human resource allocation in China, and provide basis for relevant departments to optimize nursing human resource allocation.Methods:Data were extracted from China′s health statistical yearbook from 1990 to 2019. Six indicators of the number of registered nurses, the number of registered nurses per 1 000 population, the ratio of registered nurses to health technicians, doctor-nurse ratio, hospital bed-nurse ratio and nurse-patient ratio were used to make a descriptive statistical analysis on the changing trend of nursing human resources in China.Results:From 1990 to 2019, the number of registered nurses increased from 0.970 million to 4.445 million in China, with an average annual growth rate of 5.37%, the average annual growth rate was 2.23% from 1990 to 2005, 9.96% from 2006 to 2013, and 8.21% from 2014 to 2019. The number of registered nurses per 1 000 population increased from 0.85 to 3.18, with a 4.65% annual growth rate, the doctor-nurse ratio increased from 1∶0.55 to 1∶1.15, with a 2.58% annual growth rate, the hospital bed-nurse ratio increased from 1∶0.33 to 1∶0.50, and the average annual growth rate was 1.44%. The proportion of registered nurses to health technicians increased from 24.87% in 1990 to 43.84% in 2019, however, the number of registered nurses in hospitals accounted for about 73.00% of registered nurses in health institutions.Conclusions:From 1990 to 2019, the overall allocation efficiency of nursing human resources in China has been significantly optimized, and indicators such as doctor-nurse ratio and hospital bed-nurse ratio have improved, but the growth rate is slowing down. The relevant departments need to take necessary measures to further increase the absolute and relative number of nurses to cope with the increasing service demand.

Rehabilitación vocal fisiológica con ejercicios de tracto vocal semiocluido / Physiologic voice rehabilitation with semi-occluded vocal tract exercises

Introducción. Los ejercicios de tracto vocal semiocluido (ETVSO) son herramien-tas utilizadas en la rehabilitación fisiológica de la voz. Los ETVSO son ejercicios vocales producidos por la semioclusión del tracto vocal, a través de una serie de posturas que buscan alargar y/o ocluir el tracto vocal, generando un cambio en el patrón vibratorio de los pliegues vocales, grado de aducción y el patrón respiratorio. Los ETVSO pueden dividirse, según el tipo de semioclusión, en sostenida, transitoria y oscilatoria, así como en ejercicios de mayor resistencia a menor resistencia.Objetivo. Describir los diferentes tipos de ejercicios de tracto vocal semiocluido, el tipo de semioclusión, el grado de resistencia y sus efectos en los pliegues vocales, patrón respiratorio y configuración del tracto vocal. Metodología. Se realizó una revisión de la literatura en las bases de datos PubMed, Medline y Science Direct, usando los siguientes términos: "Semi-Occluded Vocal Tract Postures", "tract vocal semiocclude" y "ejercicios de tracto vocal semiocluido". Se utilizaron operadores booleanos "AND" y "OR" para especificar la búsqueda.Resultados. Los beneficios de estos ejercicios impactan positivamente en variables aerodinámicas, en la función glótica y en la configuración del tracto vocal. Conclusiones. Los ejercicios de tracto vocal semiocluido son una familia de ejerci-cios vocales producidos por semioclusión sostenida, transitoria y oscilatoria del tracto vocal, a través de una serie de posturas que buscan alargar y/o ocluir el tracto vocal, cuyos beneficios impactan positivamente los pliegues vocales y el tracto vocal

Introduction. Semi-occluded vocal tract exercises (SOVTE) are tools used in physiologic voice rehabilitation. Semi-occluded vocal tract exercises are vocal exer-cises produced by the semi-occlusion of the vocal tract through a series of postures that seek to lengthen and/or occlude the vocal tract, generating a change in the vibratory pattern of vocal folds, degree of vocal folds adduction, and the respira-tory pattern. SOVTE can be divided, according to the type of semi-occlusion, into sustained, transient and oscillatory, as well as exercises with high and low degree of airflow resistance.Objective. To describe the different types of semi-occluded vocal tract exercises, the type of semi-occlusion, the type of resistance, and their effects on the vocal folds, respiratory pattern, and configuration of the vocal tract.Methodology. A literature review was performed in the PubMed, Medline, and Science Direct databases, using the following terms: "Semi-occluded vocal tract pos-tures", "Semi-occluded vocal tract" and "Semi-occluded vocal tract exercises". Boo-lean operators "AND" and "OR" were used to specify the search.Results. The benefits of these exercises positively impact aerodynamic variables, glottal function, and configuration of the vocal tract.Conclusions. The semi-occluded vocal tract exercises are a family of vocal exerci-ses produced by the sustained, transitory, and oscillatory semi-occlusion of the vocal tract, through a series of postures that seek to lengthen and/or occlude the vocal tract, whose benefits positively impact on vocal folds and vocal tract.