Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

Seafloor topography plays an important role in the evolution of submarine lobes.However,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine lobes.In this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East Africa.We characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic data.We find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single lobes.When the topography is irregular and presents topographic lows,lobe complexes first infill these depressions.Single lobes are deposited preferentially at positions with higher longitudinal(i.e.across-slope)slope gradients.As the longitudinal slope becomes higher,the aspect ratio of the single lobes increases.Lateral(i.e.along-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single lobes.When the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap surface.Furthermore,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,i.e.sediments tend to accumulate vertically.The results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

鼻泪管阻塞性疾病患者鼻泪管管径的研究

目的:测量鼻泪管阻塞性疾病患者鼻泪管管径,分析患眼与正常眼之间、不同性别患眼之间、不同年龄段患眼骨性鼻泪管上、中、下口横向直径的差异,探讨鼻泪管横向直径与鼻泪管阻塞疾病的关系。方法:收集2014-04/2017-01于成都中医药大学附属医院眼科就诊的鼻泪管阻塞性疾病患者152例(患眼179眼,正常眼125眼),其中男25例(患眼28眼,正常眼22眼),女127例(患眼151眼,正常眼103眼),年龄4~87(平均53.44±16.06)岁。所有患者泪道冲洗后灌注30%碘海醇注射液,并立即行泪道计算机断层扫描(computed tomography,CT)检查,三维重建鼻泪管结构图,于斜冠状位上对鼻泪管及其临近组织结构进行观察,测量并分析患眼与正常眼之间、不同性别患眼之间、不同年龄段患眼之间骨性鼻泪管上、中、下口横向直径的差异。结果:患眼与正常眼之间、不同性别患眼之间、不同年龄段患眼之间骨性鼻泪管上、中、下口横向直径值差异均无统计学意义(P>0.05)。患眼和正常眼的鼻泪管上、中、下口横向直径之间比较,差异均有统计学意义(P<0.001),其中中口横向直径最小。结论:骨性鼻泪管横向管径不是形成鼻泪管阻塞的主要原因。

Azimuthal elastic impedance-based Fourier coefficient variation with angle inversion for fracture weakness

Quantitative inversion of fracture weakness plays an important role in fracture prediction.Considering reservoirs with a set of vertical fractures as horizontal transversely isotropic media,the logarithmic normalized azimuthal elastic impedance(EI)is rewritten in terms of Fourier coefficients(FCs),the 90°ambiguity in the azimuth estimation of the symmetry axis is resolved by judging the sign of the second FC,and we choose the FCs with the highest sensitivity to fracture weakness and present a feasible inversion workflow for fracture weakness,which involves:(1)the inversion for azimuthal EI datasets from observed azimuthal angle gathers;(2)the prediction for the second FCs and azimuth of the symmetry axis from the estimated azimuthal EI datasets;and(3)the estimation of fracture weakness combining the extracted second FCs and azimuth of the symmetry axis iteratively,which is constrained utilizing the Cauchy sparse regularization and the low-frequency regularization in a Bayesian framework.Tests on synthetic and field data demonstrate that the 90°ambiguity in the azimuth estimation of the symmetry axis has been removed,and reliable fracture weakness can be obtained when the estimated azimuth of the symmetry axis deviates less than 30°,which can guide the prediction of fractured reservoirs.

Zoeppritz-based AVO inversion using an improved Markov chain Monte Carlo method

The conventional Markov chain Monte Carlo （MCMC） method is limited to the selected shape and size of proposal distribution and is not easy to start when the initial proposal distribution is far away from the target distribution. To overcome these drawbacks of the conventional MCMC method, two useful improvements in MCMC method, adaptive Metropolis （AM） algorithm and delayed rejection （DR） algorithm, are attempted to be combined. The AM algorithm aims at adapting the proposal distribution by using the generated estimators, and the DR algorithm aims at enhancing the efficiency of the improved MCMC method. Based on the improved MCMC method, a Bayesian amplitude versus offset （AVO） inversion method on the basis of the exact Zoeppritz equation has been developed, with which the P- and S-wave velocities and the density can be obtained directly, and the uncertainty of AVO inversion results has been estimated as well. The study based on the logging data and the seismic data demonstrates the feasibility and robustness of the method and shows that all three parameters are well retrieved. So the exact Zoeppritz-based nonlinear inversion method by using the improved MCMC is not only suitable for reservoirs with strong-contrast interfaces and longoffset ranges but also it is more stable, accurate and antinoise.

A two-step method to apply Xu–Payne multi-porosity model to estimate pore type from seismic data for carbonate reservoirs

Carbonate reservoirs exhibit strong heterogeneity in the distribution of pore types that can be quantitatively characterized by applying Xu–Payne multi-porosity model.However,there are some prerequisites to this model the porosity and saturation need to be provided.In general,these application conditions are difficult to satisfy for seismic data.In order to overcome this problem,we present a two-step method to estimate the porosity and saturation and pore type of carbonate reservoirs from seismic data.In step one,the pore space of the carbonate reservoir is equivalent to a single-porosity system with an effective pore aspect ratio;then,a 3D rock-physics template(RPT)is established through the Gassmann’s equations and effective medium models;and then,the effective aspect ratio of pore,porosity and fluid saturation are simultaneously estimated from the seismic data based on 3D RPT.In step two,the pore space of the carbonate reservoir is equivalent to a triple-porosity system.Combined with the inverted porosity and saturation in the first step,the porosities of three pore types can be inverted from the seismic elastic properties.The application results indicate that our method can obtain accurate physical properties consistent with logging data and ensure the reliability of characterization of pore type.

Estimation of fracture density and orientation from azimuthal elastic impedance difference through singular value decomposition

Accurate estimation of fracture density and orientation is of great significance for seismic characterization of fractured reservoirs.Here,we propose a novel methodology to estimate fracture density and orientation from azimuthal elastic impedance(AEI)difference using singular value decomposition(SVD).Based on Hudson's model,we first derive the AEI equation containing fracture density in HTI media,and then obtain basis functions and singular values from the normalized AEI difference utilizing SVD.Analysis shows that the basis function changing with azimuth is related to fracture orientation,fracture density is the linearly weighted sum of singular values,and the first singular value contributes the most to fracture density.Thus,we develop an SVD-based fracture density and orientation inversion approach constrained by smooth prior elastic parameters.Synthetic example shows that fracture density and orientation can be stably estimated,and the correlation coefficient between the true value and the estimated fracture density is above 0.85 even when an S/N ratio of 2.Field data example shows that the estimated fracture orientation is consistent with the interpretation of image log data,and the estimated fracture density reliably indicates fractured gas-bearing reservoir,which could help to guide the exploration and development of fractured reservoirs.

Vertical grain-size trend of mouth bar in lacustrine fan delta:Flume experiments

Field observational previously indicated a mouth bar of a fan delta could exhibit a fining-or coarseningupward trend,which bring a new challenge to the identification of mouth bar in subsurface studies due to the lack of morphological descriptions.Previous studies have indicated that effluent behavior in rivermouth system can affect the vertical grain-size trend of mouth bar,but the drivers and magnitude of this phenomenon are not understood.We conducted flume experiments to investigate the mechanism and controlling factors of vertical grain-size trend of mouth bar.Experiment with a steeper slope of the substrate layer,greater discharge,higher sediment/water ratio,and coarser sediment induced a finingupward trend of mouth bar,because the effluent was dominated by strong inertia.Mouth bar in the experiment with a gentler slope of the substrate layer,smaller discharge,lower sediment/water ratio,and finer sediment exhibited a coarsening-upward trend dominated by the friction-dominated effluent.The relationship between the vertical grain-size trend of mouth bar and the gradients of foreset bedding in small-scale flume models and the cut-off of 15°-18°are applicable in natural systems.Identifying depositional setting to infer depositional process in river-mouth system and analyzing the plane geometry of sandbodies are two steps in the interpretation of ancient fan deltaic rock record.

A comparative study on radiation reliability of composite channel InP high electron mobility transistors

This paper proposes a reasonable radiation-resistant composite channel structure for In P HEMTs.The simulation results show that the composite channel structure has excellent electrical properties due to increased modulation doping efficiency and carrier confinement.Moreover,the direct current(DC)and radio frequency(RF)characteristics and their reliability between the single channel structure and the composite channel structure after 75-ke V proton irradiation are compared in detail.The results show that the composite channel structure has excellent radiation tolerance.Mechanism analysis demonstrates that the composite channel structure weakens the carrier removal effect.This phenomenon can account for the increase of native carrier and the decrease of defect capture rate.

First-order multiples imaging aided by water bottom

Surface-related multiples frequently propagate into the subsurface and contain abundant information on small reflection angles.Compared with the conventional migration of primaries,migration of multiples offers complementary illumination and a higher vertical resolution.However,crosstalk artifacts caused by unrelated multiples during reverse time migration(RTM)using multiples severely degrade the reliability and interpretation of the final migration images.Therefore,we proposed RTM using first-order receiver-side water-bottom-related multiples for eliminating crosstalk artifacts and enhancing vertical resolution.We first backward propagate the first-order receiver-side water-bottom-related multiples using a water-layer model,followed by saving the upper boundary wavefield.Then we produce the source wavefield using a seismic wavelet and the receiver wavefield by back-extrapolating the saved boundary.Finally,the cross-correlation imaging condition is applied to generate the final image.This method transforms the receiver-side multiples into primaries,followed by the conventional migration processing procedures.Numerical examples using synthetic datasets demonstrate that our method significantly enhances the imaging quality by eliminating crosstalk artifacts and improving the resolution.

Monoclonal antibody targeting mu-opioid receptor attenuates morphine tolerance via enhancing morphine-induced receptor endocytosis

Morphine is a frequently used analgesic that activates the mu-opioid receptor(MOR),which has prominent side effects of tolerance.Although the inefficiency of morphine in inducing the endocytosis of MOR underlies the development of morphine tolerance,currently,there is no effective therapy to treat morphine tolerance.In the current study,we aimed to develop a monoclonal antibody(mAb)precisely targeting MOR and to determine its therapeutic efficacy on morphine tolerance and the underlying molecular mechanisms.We successfully prepared a mAb targeting MOR,named 3A5C7,by hybridoma technique using a strategy of deoxyribonucleic acid immunization combined with cell immunization,and identified it as an immunoglobulin G mAb with high specificity and affinity for MOR and binding ability to antigens with spatial conformation.Treatment of two cell lines,HEK293T and SH-SY5Y,with 3A5C7 enhanced morphine-induced MOR endocytosis via a G protein-coupled receptor kinase 2(GRK2)/b-arrestin2-dependent mechanism,as demonstrated by immunofluorescence staining,flow cytometry,Western blotting,coimmunoprecipitation,and small interfering ribonucleic acid(siRNA)-based knockdown.This mAb also allowed MOR recycling from cytoplasm to plasma membrane and attenuated morphine-induced phosphorylation of MOR.We established an in vitro morphine tolerance model using differentiated SH-SY5Y cells induced by retinoic acid.Western blot,enzyme-linked immunosorbent assays,and siRNA-based knockdown revealed that 3A5C7 mAb diminished hyperactivation of adenylate cyclase,the in vitro biomarker of morphine tolerance,via the GRK2/b-arrestin2 pathway.Furthermore,in vivo hotplate test demonstrated that chronic intrathecal administration of 3A5C7 significantly alleviated morphine tolerance in mice,and withdrawal jumping test revealed that both chronic and acute 3A5C7 intrathecal administration attenuated morphine dependence.Finally,intrathecal electroporation of silencing short hairpin RNA illustrated that the in vivo anti-tolerance and anti-dependence efficacy of 3A5C7 was mediated by enhanced morphine-induced MOR endocytosis via GRK2/b-arrestin2 pathway.Collectively,our study provided a therapeutic mAb,3A5C7,targeting MOR to treat morphine tolerance,mediated by enhancing morphine-induced MOR endocytosis.The mAb 3A5C7 demonstrates promising translational value to treat clinical morphine tolerance.

Clinical features and prognosis of multiple myeloma and orbital extramedullary disease:Seven cases report and review of literature

BACKGROUND Multiple myeloma(MM)complicated with extramedullary disease(EMD)has a poor prognosis and is a limiting factor in the treatment of MM,and no standard treatment is recommended in international guidelines.Few studies have reported MM with periorbital EMD.CASE SUMMARY In this paper,the clinical characteristics and survival of seven patients with multiple myeloma and orbital are described and analyzed.The common ocular symptoms were blurred vision,proptosis and/or eye movement disorders,IgG type MM may be a risk factor for orbital involvement.Of them,six patients were treated with bortezomib-based regimens.The median overall survival(OS)and progression free survival for the entire cohort were 48 and 33 mo,respectively,which was much worse than the OS reported for MM patients without orbital EMD.CONCLUSION Orbital MM may have significantly shortened survival for the entire cohort,so multidisciplinary collaboration is emphasized and recommended in the diagnosis and treatment of these difficult cases.

Investigation and analysis of 14034 college students on COVID-19 and its countermeasures and suggestions

Objective:To understand the current situation of college students'knowledge,cognitive attitude and behavior(KAP)towards the prevention and control of Corona Virus Disease 2019(Corona Virus Disease 2019,COVID-19)during the epidemic,so as to provide theoretical basis for college students'resumption of study and campus prevention and control.Methods:A questionnaire survey was conducted among 16,410 college students by using the convenient sampling method of,One-Way ANOVA and Logistic regression analysis of the survey data.Results:The total awareness rate of college students on COVID-19 was 85%,the average knowledge score was(70.4±10.0),and the proportion of high cognition was 74.5%.The average attitude score of college students was(3.78±0.55),and only 3.9%of them held a positive attitude.The average score of college students'protective behaviors was(19.35±1.69),and 48.8%of them took good protective behaviors.Binary logistic regression analysis showed that the proportion of students with high cognition who adopt good protective behaviors is higher than that of students with low cognition(95%CI:0.621-0.752).The proportion of students with a positive attitude to adopt good behaviors was higher than that with a negative attitude(95%CI:1.398-2.009),Spearman rank correlation analysis results showed that there was a weak positive correlation between cognition and attitude(r=0.056,P<0.05),and a weak positive correlation between cognition and behavior(r=0.118,P<0.05),and a weak positive correlation between attitude and behavior(r=0.038,P<0.05).Conclusion:College students have a good overall cognition of COVID-19,but their attitudes and protective behaviors need to be further improved.Therefore,knowledge education,behavioral intervention and psychological counseling on COVID-19 epidemic prevention and control among college students should be strengthened to improve their prevention and control ability and physical quality.

Research on the architecture of submarine-fan lobes in the Niger Delta Basin,offshore West Africa

As one of the most important reservoirs in submarine fan, submarine lobes are hot fields for the deep-water oil-gas exploration in the world. Although a large amount of researches have been carried out on the architecture model of submarine lobes throughout the world, some controversies still exist on aspects such as the differential distribution of composite patterns and the quantitative relationships among different sedimentary settings. This paper, which took an oilfietd in the Niger Delta Basin offshore West Afnca as an example and utilized abundant core, welt-logging and seismic data comprehensively, established the semi- quantitative to quantitative architecture model for individual lobe and lobe complex. Results show that （1） A lobe complex was composed of multiple individual lobes as the compensational stacking pattern. According to the stacked relationship among individual lobes, four types of compensational stacking pattern were classified as the inordered type, the lateral migration type, the retrograding type and the prograding type. Influenced by the laterally confined degree of palaeotopography, the basin floor fan lobe complex was easily superimposed as inordered type, showing relatively large lateral width but relatively small thickness; the slope fan lobe complex was easily superimposed as lateral migration, retrograding and pro- grading types, showing relatively small lateral width but relatively large thickness. （2） Influenced by the laterally confined degree of palaeotopography, the basin floor fan individual lobes showed relatively large planar distribution area but relatively small thickness, while the slope fan individual lobes showed relatively small planar distribution area but relatively large thickness. An individual lobe was composed of multiple lobe stories by the way of aggradation-progradation pattern. From proximal to middle and distal part of individual lobes, the bottom mass-transport-deposits and the top branch channels disappeared gradually, and the amalgamated degree of the middle tabular sandbodies weakened as well with gradually developing of muddy interlayers. The formation of an individual lobe generally includes three stages as ＂rapid accumulation-progradation-aggradation＂.

Overview of the systematic reviews of premature ovarian insufficiency treated with acupuncture

Objective:To assess the reliability of the methodological quality and outcome measures of systematic reviews(SR)/meta-analysis of premature ovarian insufficiency(POI) treated with acupuncture.Methods:SR/meta-analysis of POI treated with acupuncture were searched on POI from the databases including PubMed,Web of Science,EMBase,the Cochran Library,Chinese biomedical literature database(SinoMed),China journal full-text database(CNKI),Wanfang data knowledge service platform(Wanfang)and VIP information Chinese periodical service platform(VIP),from inception to 1 st May 2021.Using A Measurement Tool to Assess Systematic Reviews 2(AMSTAR 2) scale and Grades of Recommendations Assessment,Development and Evaluation(GRADE) system,the methodological quality and outcome measures of the included studies were appraised.Results:Ten articles of SR/meta-analysis were included,published from 2015 to 2020.Using AMSTAR 2,5 articles of SR/meta-analysis were rated as critical low quality in methods,3 articles as low quality,and2 articles as moderate quality.The results of GRADE showed that among the 50 outcomes the quality of evidence of 22 outcomes was very low,that of 25 outcomes was low and that of 3 outcomes was moderate.Conclusion:The methodological quality and the reliability of outcome measures were not high in existing SR/meta-analysis on POI treated with acupuncture,which may affect the translation of the SR/metaanalysis findings into clinical practice.It is necessary to further strengthen the methodological quality and reporting standard of SR/meta-analysis,as well as the robustness of design and implementation of randomized controlled trials(RCTs),in order to generate high quality evidences for clinical decision-making and practice.

Effect of 43 cases of temporomandibular joint dysfunction treated with thumb-tack needle based on the meridian cutaneous region theory

Objective： To observe the clinical efficacy of thumb-tack needle on temporomandibular joint dysfunction（TMD）.Methods： A total of 43 outpatients of TMD were treated with thumb-tack needle. After the skin routine sterilization, the intradermal needles, 0.2 mm x 1.5 mm（the SEIRIN-thumb-tack needle） were embedded subcutaneously at Zúlinqì（足临泣GB 41）, Zhōngzhǔ（中渚 TE 3） and Xiàguān（下关 ST 7） on the affected side. The acupoints were pressed and kneaded gently to induce mild soreness and distention.When pressing and kneading GB 41 and TE 3, the patients were required to open and close the mouth in small amplitude to achieve the effects of kinetic acupuncture. The treatment was given twice a week.The needles were retained for 24 h. A total of 6 treatments were required.Results： A total of 22 cases were cured, accounting for 51.16%, 15 cases effective remarkably, accounting for 34.88% and 6 cases failed, accounting for 13.95%. The total effective rate was 86.05%.Conclusion： The thumb-tack needle is significantly effective on TMD.

Multi-epitope chimeric antigen used as a serological marker to estimate Plasmodium falciparum transmission intensity in the border area of China-Myanmar

Background:Following the decline of malaria transmission in many countries and regions,serological parameters have become particularly useful for estimating malaria transmission in low-intensity areas.This study evaluated a novel serological marker,Malaria Random Constructed Antigen-1(M.RCAg-1),which contains 11 epitopes from eight Plasmodium falciparum antigens,as a tool for assessing malaria transmission intensity along the border area of China-Myanmar.Method:Serum from Plasmodium falciparum and P.vivax patients was used to detect the properties of M.RCAg-1 and antibody responses.Cross-sectional surveys were conducted at the China-Myanmar border and in Hainan province in 2012 and 2013 using cluster sampling.Filter blood spot papers were collected from all participants.Antibodies against M.RCAg-1 were detected using indirect ELISA.The Mann–Whitney test and Spearman’s rank correlation test were performed to analyze antibody data.P.falciparum malaria transmission intensity was estimated using a catalytic conversion model based on the maximum likelihood of generating a community seroconversion rate(SCR).Results:M.RCAg-1 was well-recognized by the naturally acquired anti-malaria antibodies in P.falciparum patients and had very limited cross-reactivity with P.vivax infection.The total amount of IgG antibodies was decreased with the decrease in parasitemia after taking medication and lasted several weeks.In a population survey,the antibody levels were higher in residents living close to the China-Myanmar border than those living in non-epidemic areas(P<0.0001),but no significant difference was observed between residents from Hainan and non-epidemic areas.The calculated SCR was 0.0128 for Jieyangka,0.004 for Susuzhai,0.0047 for Qiushan,and 0.043 for Kayahe.The estimated exposure rate obtained from the anti-M.RCAg-1 antibody level correlated with traditional measures of transmission intensity derived from altitude.Conclusion:Our study demonstrates that M.RCAg-1 is potentially useful as a serological indicator of exposure to P.falciparum malaria,especially for malaria surveillance in low transmission areas.

IgA Type Multiple Myeloma, Clinical Features, and Prognosis

To the Editor：In the past 10 years,remarkable progress has been made in the treatment of multiple myeloma （MM）.In clinical practice,we used Durie-Salmon Staging System （DSS）,International Staging System （ISS）,and revised ISS to judge the prognosis of myeloma patients.MM is divided into eight types,the type of IgA is considered to be poor prognosis,but so far there is no evidence basis of literature.We analyzed the clinical features and living conditions of IgA type MM patients in the real world.

A comprehensive error calibration method based on dual uniform circular array

Based on the dual uniform circular array, a novel method is proposed to estimate the direction-of-arrival (DOA) and jointly calibrate gain-phase errors, position errors, and mutual coupling errors. In this paper, only one auxiliary source is required to generate three time-disjoint calibration sources with the help of the rotation platform. Subsequently, according to the principle that the signal subspace is orthogonal to the noise subspace, the cost function is constructed. The alternating iteration method is used to estimate the coefficients of the three kinds of errors. During the process, the proposed algorithm makes full use of the structural characteristics of the array when estimating mutual coupling errors, while the signal phase matrix is used to eliminate the phase influence caused by the delay in signal arrival at the antenna array when estimating gain-phase errors and position errors. Compared with the algorithm using multidimensional nonlinear search, the proposed algorithm has lower computational com-plexity. Moreover, our algorithm does not require additional auxiliary sensors. Simulation results demonstrate that the proposed algorithm is effective and can precisely and comprehensively calibrate the errors in a dual uniform circular array.

Sedimentary-tectonic interaction on the growth sequence architecture within the intraslope basins of deep-water Niger Delta Basin

This paper presents a 3D seismic-based case study from the deep-water Niger Delta Basin to investigate sedimentary-tectonic interaction on growth sequence architecture within the thrust-related intraslope or piggyback basins. Gravitational contraction in the lower continental slope had yielded a series of thrust faults and associated folds in the study area, which formed several piggyback basins. These basins were filled by a suite of growth sequences with varying stratigraphic architecture. Analysis of the 3D seismic data recognized three primary seismic facies types respectively as: convergent, draping and chaotic, which contain seven subtypes. These facies types are combined to form different filling successions for convergent or chaotic growth sequences. The convergent growth sequences mainly occur in the deep section of basin fills during strong gravitational deformation, and always began with convergent-baselapping strata succeeded by convergent-thinning strata, representing pond-to-bypass transition in the ponded-basin accommodation space. The chaotic growth sequences mainly occur in the shallow section of basin fills in response to weak gravitational deformation, and usually began with debris-flow deposits succeeded by channel-levee complexes, reflecting dominant erosion-bypass processes in the slope accommodation space. A dynamic fill-andspill model considering relationship between episodic sedimentation rate and structural growth rate is proposed to explain the formative mechanisms of growth strata units and associated successions. Interaction between glaciation or deglaciation and sea-level change and gravitational deformation history are suggested to be the factor which resulted in the complex stratal stacking patterns, including progradational or retrogradational stacking patterns within convergent growth sequences, and progradational stacking patterns within chaotic growth sequences.

A report on the syndrome of inappropriate anti-diuretic hormone secretion associated with multiple myeloma

To the Editor:Hyponatremia,defined as a serum sodium concentration<135 mmol/L,is the most common waterelectrolyte imbalance in clinical practice.Hyponatremia can be a complication of other diseases(eg,heart failure,renal failure,pneumonia).Hyponatremia can be divided into three main classes:hypovolemic;euvolemic,hypervolemic.The pathogenesis of hyponatremia including taking drugs such as water pills(diuretics)and some antidepressants and pain medications;heart failure and kidney or liver disease,bouts of chronic,severe diarrhea or vomiting.