Distribution and Formation Causes of PM_(2.5) and O_(3) Double High Pollution Events in China during 2013–20

Fine particulate matter(PM_(2.5))and ozone(O_(3))double high pollution(DHP)events have occurred frequently over China in recent years,but their causes are not completely clear.In this study,the spatiotemporal distribution of DHP events in China during 2013–20 is analyzed.The synoptic types affecting DHP events are identified with the Lamb–Jenkinson circulation classification method.The meteorological and chemical causes of DHP events controlled by the main synoptic types are further investigated.Results show that DHP events(1655 in total for China during 2013–20)mainly occur over the North China Plain,Yangtze River Delta,Pearl River Delta,Sichuan Basin,and Central China.The occurrence frequency increases by 5.1%during 2013–15,and then decreases by 56.1%during 2015–20.The main circulation types of DHP events are“cyclone”and“anticyclone”,accounting for over 40%of all DHP events over five main polluted regions in China,followed by southerly or easterly flat airflow types,like“southeast”,“southwest”,and“east”.Compared with non-DHP events,DHP events are characterized by static or weak wind,high temperature(20.9℃ versus 23.1℃)and low humidity(70.0%versus 64.9%).The diurnal cycles of meteorological conditions cause PM_(2.5)(0300–1200 LST,Local Standard Time=UTC+8 hours)and O_(3)(1500–2100 LST)to exceed the national standards at different periods of the DHP day.Three pollutant conversion indices further indicate the rapid secondary conversions during DHP events,and thus the concentrations of NO_(2),SO_(2) and volatile organic compounds decrease by 13.1%,4.7%and 4.4%,respectively.The results of this study can be informative for future decisions on the management of DHP events.

Analysis of the causes of primary revision after unicompartmental knee arthroplasty: A case series

BACKGROUND Unicompartmental knee arthroplasty(UKA)has great advantages in the treatment of unicompartmental knee osteoarthritis,but its revision rate is higher than that of total knee arthroplasty.AIM To summarize and analyse the causes of revision after UKA.METHODS This is a retrospective case series study in which the reasons for the first revision after UKA are summarized.We analysed the clinical symptoms,medical histories,laboratory test results,imaging examination results and treatment processes of the patients who underwent revision and summarized the reasons for primary revision after UKA.RESULTS A total of 13 patients,including 3 males and 10 females,underwent revision surgery after UKA.The average age of the included patients was 67.62 years.The prosthesis was used for 3 d to 72 months.The main reasons for revision after UKA were improper suturing of the surgical opening(1 patient),osteophytes(2 patients),intra-articular loose bodies(2 patients),tibial prosthesis loosening(2 patients),rheumatoid arthritis(1 patient),gasket dislocation(3 patients),anterior cruciate ligament injury(1 patient),and medial collateral ligament injury with residual bone cement(1 patient).CONCLUSION The causes of primary revision after UKA were gasket dislocation,osteophytes,intra-articular loose bodies and tibial prosthesis loosening.Avoidance of these factors may greatly reduce the rate of revision after UKA,improve patient satisfaction and reduce medical burden.

基于Transformer的矿井内因火灾时间序列预测方法

传统的基于机器学习的矿井内因火灾预测方法尽管具备一定的预测能力,然而在处理复杂的多变量数据时不能有效捕捉数据间的全局依赖关系,导致预测精度较低。针对上述问题,提出了一种基于Transformer的矿井内因火灾时间序列预测方法。首先,采用Hampel滤波器和拉格朗日插值法对数据进行异常值检测和缺失值填补。然后,利用Transformer的自注意力机制对时间序列数据进行特征提取及趋势预测。最后,通过调节滑动窗口的大小与步长,在不同的时间步长和预测长度下对模型进行不同时间维度的训练。结合气体分析法将矿井火灾产生的标志性气体(CO,O_(2),N_(2),CO_(2),C_(2)H_(2),C_(2)H4,C_(2)H_(6))作为模型输入变量,其中CO作为模型输出的目标变量,O_(2),N_(2),CO_(2),C_(2)H_(2),C_(2)H4,C_(2)H_(6)作为模型输入的协变量。选取陕煤集团柠条塔煤矿S1206回风隅角火灾预警的束管数据进行实验验证,结果表明:①对CO进行单变量预测和多变量预测,多变量预测相比单变量预测有着更高的预测精度,说明多变量预测能通过捕捉序列间的相关性提高模型的预测精度。②当时间步长固定时,基于Transformer的矿井内因火灾预测模型的预测精度随着预测长度的增加而下降。当预测长度固定时,模型的预测精度随时间步长增加而提高。③Transformer算法的预测精度较长短时记忆(LSTM)算法和循环神经网络(RNN)算法分别提高了7.1%~12.6%和20.9%~24.9%。

Characteristics and Preliminary Causes of Tropical Cyclone Remote Precipitation over China

In this study,the characteristics and preliminary causes of tropical cyclone remote precipitation(TRP)over China during the period from 1979 to 2020 are investigated.Results indicated that approximately 72.42%of tropical cyclones(TCs)in the Western Pacific produce TRP over China.The peak months for TRP are July and August.The four key regions of TRP are the adjacent areas between the Sichuan and Shaanxi Provinces,the northern coast of the Bohai Sea,the coast of the Yellow Sea,and the southern coast area.The typical distance between the station with TRP and the TC center ranges from 1500 to 2500 km.Most of these stations are situated north to 60°west of north of the TC.The south–west water vapor transportation on the west side of the TC is crucial to TRP.TRP has a decreasing trend because of the decrease in the number of TCs that generate TRP.From the perspective of large-scale environmental conditions,a decrease in the integrated horizontal water vapor transport in China' Mainland,the weakening of upward motion at approximately 25°–35°N,which is inconducive to convection,and an increase in low-level vertical wind shear,which is unfavorable for the development of TC in areas with high frequencies of TRP-related TCs,are the factors that result in the decreasing trend of TRP.

Enhancing Unsupervised Domain Adaptation for Person Re-Identification with the Minimal Transfer Cost Framework

In Unsupervised Domain Adaptation(UDA)for person re-identification(re-ID),the primary challenge is reducing the distribution discrepancy between the source and target domains.This can be achieved by implicitly or explicitly constructing an appropriate intermediate domain to enhance recognition capability on the target domain.Implicit construction is difficult due to the absence of intermediate state supervision,making smooth knowledge transfer from the source to the target domain a challenge.To explicitly construct the most suitable intermediate domain for the model to gradually adapt to the feature distribution changes from the source to the target domain,we propose the Minimal Transfer Cost Framework(MTCF).MTCF considers all scenarios of the intermediate domain during the transfer process,ensuring smoother and more efficient domain alignment.Our framework mainly includes threemodules:Intermediate Domain Generator(IDG),Cross-domain Feature Constraint Module(CFCM),and Residual Channel Space Module(RCSM).First,the IDG Module is introduced to generate all possible intermediate domains,ensuring a smooth transition of knowledge fromthe source to the target domain.To reduce the cross-domain feature distribution discrepancy,we propose the CFCM Module,which quantifies the difficulty of knowledge transfer and ensures the diversity of intermediate domain features and their semantic relevance,achieving alignment between the source and target domains by incorporating mutual information and maximum mean discrepancy.We also design the RCSM,which utilizes attention mechanism to enhance the model’s focus on personnel features in low-resolution images,improving the accuracy and efficiency of person re-ID.Our proposed method outperforms existing technologies in all common UDA re-ID tasks and improves the Mean Average Precision(mAP)by 2.3%in the Market to Duke task compared to the state-of-the-art(SOTA)methods.

Tool Wear State Recognition with Deep Transfer Learning Based on Spindle Vibration for Milling Process

The wear of metal cutting tools will progressively rise as the cutting time goes on. Wearing heavily on the toolwill generate significant noise and vibration, negatively impacting the accuracy of the forming and the surfaceintegrity of the workpiece. Hence, during the cutting process, it is imperative to continually monitor the tool wearstate andpromptly replace anyheavilyworn tools toguarantee thequality of the cutting.The conventional tool wearmonitoring models, which are based on machine learning, are specifically built for the intended cutting conditions.However, these models require retraining when the cutting conditions undergo any changes. This method has noapplication value if the cutting conditions frequently change. This manuscript proposes a method for monitoringtool wear basedonunsuperviseddeep transfer learning. Due to the similarity of the tool wear process under varyingworking conditions, a tool wear recognitionmodel that can adapt to both current and previous working conditionshas been developed by utilizing cutting monitoring data from history. To extract and classify cutting vibrationsignals, the unsupervised deep transfer learning network comprises a one-dimensional (1D) convolutional neuralnetwork (CNN) with a multi-layer perceptron (MLP). To achieve distribution alignment of deep features throughthe maximum mean discrepancy algorithm, a domain adaptive layer is embedded in the penultimate layer of thenetwork. A platformformonitoring tool wear during endmilling has been constructed. The proposedmethod wasverified through the execution of a full life test of end milling under multiple working conditions with a Cr12MoVsteel workpiece. Our experiments demonstrate that the transfer learning model maintains a classification accuracyof over 80%. In comparisonwith the most advanced tool wearmonitoring methods, the presentedmodel guaranteessuperior performance in the target domains.

Simple bone cysts of the proximal humerus presented with limb length discrepancy:A case report

BACKGROUND Simple bone cysts(SBC)are benign tumor-like bone lesions typically identified in children.While SBC may lead to growth disturbances or growth arrest,such cases are uncommon.The mechanisms behind these observations remain unclear.Additionally,research on the etiology of SBC remains inconclusive,and there has been no consensus on the appropriate timing and methodology for treatment.CASE SUMMARY Here,we present our experience in the successful surgical management of a 10-year-old girl with SBC,who presented with a pathological fracture complicated by malunion of the displaced fracture,varus deformity,and limb length discrepancy.We hypothesized two possible etiologies for the patient’s growth arrest and subsequent humerus varus deformity:(1)Direct disruption of the physis by fluid from the cyst itself;and(2)damage to the epiphysis due to repetitive pathological fractures associated with SBC.In addressing this case,surgical intervention was undertaken to correct the proximal humerus varus deformity.This approach offered the advantages of simultaneously correcting angular abnormalities,achieving mild limb lengthening,providing definitive SBC treatment,and reducing the overall treatment duration.CONCLUSION As per current literature,acute correction of acute angular deformity in proximal humeral SBC is not well comprehended.However,in this specific case,acute correction was considered an optimal solution.

Time-Lapse Full-Waveform Inversion Using Cross-Correlation-Based Dynamic Time Warping

Offshore carbon capture, utilization, and storage(OCCUS) is regarded as a crucial technology for mitigating greenhouse gas emissions.Quantitative monitoring maps of sealed carbon dioxide are necessary in a comprehensive OCCUS project. A potential high-resolution method for the aforementioned purpose lies in the full-waveform inversion(FWI) of time-lapse seismic data. However, practical applications of FWI are severely restricted by the well-known cycle-skipping problem. A new time-lapse FWI method using cross-correlation-based dynamic time warping(CDTW) is proposed to detect changes in the subsurface property due to carbon dioxide(CO_(2)) injection and address the aforementioned issue. The proposed method, namely CDTW, which combines the advantages of cross-correlation and dynamic time warping, is employed in the automatic estimation of the discrepancy between the seismic signals simulated using the baseline/initial model and those acquired. The proposed FWI method can then back-project the estimated discrepancy to the subsurface space domain, thereby facilitating retrieval of the induced subsurface property change by taking the difference between the inverted baseline and monitor models. Numerical results on pairs of signals prove that CDTW can obtain reliable shifts under amplitude modulation and noise contamination conditions. The performance of CDTW substantially outperforms that of the conventional dynamic time warping method. The proposed time-lapse fullwaveform inversion(FWI) method is applied to the Frio-2 CO_(2) storage model. The baseline and monitor models are inverted from the corresponding time-lapse seismic data. The changes in velocity due to CO_(2) injection are reconstructed by the difference between the baseline and the monitor models.

Prevalence and Causes of Neonatal Mortality at Chu-Mel, Cotonou in 2023

Introduction: Neonatal mortality represents a global health problem that has been at the core of programs developed by the World Health Organization (WHO) for more than 30 years. In our country, it represents a real scourge and remains high despite the efforts made by the Ministry of Health. The goal of this study was to investigate the prevalence and causes of neonatal mortality at CHU-MEL of Cotonou in 2023. Material and Methods: This was a cross-sectional and descriptive study with retrospective data collection, carried out in the neonatology unit of the Mother and Child Teaching Hospital of Lagune (CHU-MEL) in Cotonou over a period of six months from January 1, 2023 to June 30, 2023. All neonates, premature or full-term, born alive and who died during hospitalization in the unit were included. Results: 211 cases of neonatal deaths were recorded among the 2884 neonates hospitalized in the unit during the study period, representing a hospital prevalence of 7.31%. Early neonatal mortality represented 81.5% of cases. The average age at admission was 4.6 days ± 5.3. The average weight of deceased neonates was 1609.08 ± 798.35 g. The most frequent reasons for hospitalization were represented by prematurity (60.66%) and respiratory distress (23.22%), respectively. Prematurity was the leading cause of neonatal mortality (41.7%), followed by neonatal infections (29.4%) and perinatal asphyxia (10.9%). Conclusion: The prevalence of neonatal mortality in the neonatology unit of CHU-MEL is high. Efforts to improve the quality of perinatal care departments must be intensified to reduce this prevalence.

The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries

This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urbanization, invaded by non-local plants, or enclosed for individual use and by subdividing farmlands into subsequent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possible. Land fragmentation is one of the key reasons why the ability of most resources in East Africa becomes scarcer, and those remaining become “privatized” by more powerful community members—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further by affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation problems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighboring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a substantial increase in population density. The study review further explores the trend in the performance of agriculture by average farm sizes within the intervals of five years by highlighting their strong linkages and found that the average farm size has declined drastically, especially for Kenya. This can only mean that small farms kept becoming smaller and smaller and that there were more small-scale farmers. The results further depicted that the major and commonly cultivated food crops among the East African countries include maize, sorghum, rice, cassava, sweet potatoes, bananas, Irish potatoes, beans, peas, etc., with maize yields (Mt/ha) in 2003 for Uganda being the highest (1.79 Mt/ha) and the lowest in Rwanda (0.77 Mt/ha) respectively. Therefore, from the review results, recommendations are being made as to how the negative impacts of land fragmentation on agricultural productivity can be reduced or mitigated. One way is by community sensitization and awareness about the importance of land consolidation and its proposition on farm productivity.

Tumor size discrepancy between endoscopic and pathological evaluations in colorectal endoscopic submucosal dissection

BACKGROUND Tumor size impacts the technical difficulty and histological curability of colorectal endoscopic submucosal dissection(ESD);however,the preoperative evaluation of tumor size is often different from histological assessment.Analyzing influential factors on failure to obtain an accurate tumor size evaluation could help prepare optimal conditions for safer and more reliable ESD.METHODS This was a retrospective study conducted at a single institution.A total of 377 lesions removed by colorectal ESD at our hospital between April 2018 and March 2022 were collected.We first assessed the difference in size with an absolute per-centage of the scaling discrepancy.Subsequently,we compared the clinicopatho-logical characteristics of the correct scaling group(>-33%and<33%)with that of the incorrect scaling group(<-33%or>33%),which was further subdivided into the underscaling group(-33%or less of the discrepancy)and overscaling group(33%or more of the discrepancy),respectively.As secondary outcome measures,parameters on size estimation were compared between the underscaling and correct scaling groups,as well as between the overscaling and correct scaling groups.Finally,multivariate analysis was performed in terms of the following relevant parameters on size estimation:Pathological size,location,and possible influential factors(P<0.1)in the univariate analysis.RESULTS The mean of absolute percentage in the scaling discordance was 21%,and 91 lesions were considered to be incorrectly estimated in size.The incorrect scaling was significantly remarkable in larger lesions(40 mm vs 28 mm;P<0.001)and less experience(P<0.001),and these two factors were influential on the underscaling(75 lesions;P<0.001).Conversely,compared with the correct scaling group,16 lesions in the overscaling group were significantly small(20 mm vs 28 mm;P<0.001),and the small lesion size was influential on the overscaling(P=0.002).CONCLUSION Lesions indicated for colorectal ESD tended to be underestimated in large tumors,but overestimated in small ones.This discrepancy appears worth understanding for optimal procedural preparation.

Eternal Climate Change Patterns and the Causes and Countermeasures of Global Climate Change

It is an objective fact that the weather is unpredictable.Even the famous meteorologist,Academician Chu Ko Chen,has only a partial understanding of the changing laws of wind and rain.Even though ancient people summarized the 24 solar terms by observing the annual activities of the sun for a long time,because they ignored the impact of the activities of the moon on the Earth’s climate change on a small scale,the 24 solar terms they summarized often could not accurately predict the change of the Earth’s climate.Therefore,the author studied the influence of lunar activities on the Earth’s climate change,finds out the law of the influence of lunar activities on the Earth’s climate change on a small scale,and summarizes the eternal climate change pattern determined by the activities of the sun and the moon.In addition,the author also reveals the causes and countermeasures of global warming and the frequent occurrence of extreme weather as well as environmental change.

Analysis on Current Situation,Formation Causes and Control Countermeasures of Acid Rain Pollution in China

Environmental problem is one of three major issues of common concern in the world today.Being a developing socialist country,the environmental problems in china are even more prominent,mainly in population expansion,sharp decrease of global forest areas,soil erosion,acid rain pollution,water pollution and so on.This essay is to introduce the present status,formation causes and hazardous condition of acid rain pollution in china.Some feasible and effective control measures are put forward according to the actual situation in China.

Analysis of Causes for An Unusual Cloudy-rainy Weather for Several Days in Autumn

Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of this process were analyzed in this article in terms of general circulation,character of physical quantity and tropical cyclone.The result showed that the precipitation process was a long wave adjustment process and it took place during the transformation process of general circulation turning from the zonal to the radial.During the cloudy-rainy weather process,the Ural mountain ridge and the Western Pacific subtropical high were more abnormally strong and in the further north than that in any other years.The tropical cyclone in the south of the subtropical cyclone activity was more frequent.There was more shortwave in middle latitudes of Asian.The cold air masses Siberia went down south.The cold air masses joined with the current of air in the Lower Yellow River.This led to the lasting cloudy-rainy weather for several days in Shandong.

Analysis of the Causes of Continuous Cropping Obstacles for Atractylodes macrocephala Koidz in Pingjiang County and Its Control Methods

First at all, it introduced the concept and the damages of continuous cropping obstacle. Then, it analyzed the causes of continuous cropping obstacles for Atractylodes macrocephala Koidz. In the end, in order to provide guidance for pro- moting sustainable development of Atractylodes macrocephala Koidz industry in Pingjiang County, it put forward some control methods for eliminating continuous cropping obstacles of Atractylodes macrocephala Koidz, including breeding varieties with high resistance; applying rotation cropping and intercropping reasonable; rational fertilization and soil disinfection; introducing antagonistic bacterial and eliminating au- tointoxication.

The Study for the Causes of Pragmatic Failure

This paper,based on the questionnaire,deduces the causes of pragmatic failure which are summarized into four:The different value orientation between the two cultures,consisting individualism versus collectivism,power distance,connotation versus denotation,and orientation towards time,negative transfer of equivalent structures and behaviors,insufficient or improper teaching and the scarcity of universal knowledge for communication.

New Evidences on the Climatic Causes of the Formation of the Spring Persistent Rains over Southeastern China

The spring persistent rains（SPR）over southeastern China（SEC）are a unique synoptic and climatic phenomenon in East Asia.A former study has found that the southwesterly flow which lies on the southeastern flank of the Tibetan Plateau（TP）is one of the deflected westerly flows of the TP,and it is suggested to be the direct climatic cause of SPR.This study found that the southwesterly flow is also highly correlated with the sensible heating of the southeastern TP in interannual variability,in addition to having a high correlation in seasonal variability.These facts suggest that the thermal forcing of the TP is another important climatic cause of SPR.Numerical sensitivity experiments further prove that the mechanical and thermal forcings of the TP are the climatic causes of the formation of the SPR.On the other hand,the Nanling Mountains and Wuyi Mountains（NWM）over southeastern China not only increase the SPR precipitation amount evidently,but also make the SPR rain belt move to the south by blocking the strong southwesterly flow.

NEW LOWER BOUNDS FOR LEE DISCREPANCY ON TWO AND THREE MIXED LEVELS FACTORIALS

The objective of this paper is to study the issue of uniformity on asymmetrical designs with two and three mixed levels in terms of Lee discrepancy. Based on the known formulation, we present a new lower bound of Lee discrepancy of fractional factorial designs with two and three mixed levels. Our new lower bound is sharper and more valid than other existing lower bounds in literature, which is a useful complement to the lower bound theory of discrepancies.

Population attributable risks of cigarette smoking for deaths of all causes, all cancers and other chronic diseases among adults aged 40-74 years in urban Shanghai, China

Objective： To evaluate the population attributable risks （PARs） between cigarette smoking and deaths of all causes, all cancers, lung cancer and other chronic diseases in urban Shanghai. Methods： In total, 61,480 men aged 40-74 years from 2002 to 2006 and 74,941 women aged 40-70 years from 1997 to 2000 were recruited to undergo baseline surveys in urban Shanghai, with response rates of 74.0% and 92.3%, respectively. A Cox proportional hazards regression model was used to estimate relative risks （RRs） and 95% confidence intervals （95% CIs） of deaths associated with cigarette smoking. PARs and 95 % CIs for deaths were estimated from smoking exposure rates and the estimated RRs. Results： Cigarette smoking was responsible for 23.9% （95% CI： 19.4-28.3%） and 2.4% （95% Ch 1.6- 3.2%） of all deaths in men and women, respectively, in our study population. Respiratory disease had the highest PAR in men [37.5% （95% CI： 21.5-51.6%）], followed by cancer [31.3% （95% Ch 24.6-37.7%）] and cardiovascular disease （CVD） [24.1% （95% CI： 16.7-31.2%）]. While the top three PARs were 12.7% （95% CI： 6.1-19.3%）, 4.0% （95% CI： 2.4-5.6%）, and 1.1% （95% CI： 0.0-2.3%）, for respiratory disease, CVD, and cancer, respectively in women. For deaths of lung cancer, the PAR of smoking was 68.4% （95% CI： 58.2- 76.5%） in men. Conclusions： In urban Shanghai, 23.9% and 2.4% of all deaths in men and women could have been prevented if no people had smoked in the area. Effective control programs against cigarette smoking should be strongly advocated to reduce the increasing smoking-related death burden.

Analysis of Causes for an Uncommon Persistent Heavy Rain During Winter

[Objective] The aim was to study the causes for one large scale of consecutive rainstorm process in the winter of 2010 in Guangxi. [Method] The characteristics and causes of the uncommon persistent heavy rain occurring in Guangxi in January, 2010 were analyzed by using synoptic observation data, NCEP 1°×1° per six hours Global Data Assimilation System reanalysis data and satellite image. [Result] The results showed that this persistent heavy rain process was associated with abnormal intensity and the stability of the western pacific subtropical high. The heavy rain was caused by the cloud system maintaining for a long time on the edge of subtropical high. The convergence of the infrequent southeast jet was the primary cause of the uncommon heavy rain. MPV1>0, and MPV2<0 at 700 hPa were the favorable conditions for the heavy rain. The magnitude of MPV1 and MPV2 was equivalent. [Conclusion] The study provided reference for the forecast of the following similar extreme weather.