Lung cancer metastasis-induced distal esophageal segmental spasm confirmed by individualized peroral endoscopic myotomy:A case report

BACKGROUND Peroral endoscopic myotomy(POEM)has been widely performed as a standard treatment for achalasia;however,its efficacy and safety for treating distal esophageal segmental spasms induced by cancer metastasis remain unknown.CASE SUMMARY A 72-year-old male was referred to our hospital and complained of progressive dysphagia for two years.Endoscopy revealed a 2 cm long segment esophageal stenosis with intact mucosa and normal cardia.Computed tomography showed a right upper lung mass,and pathology of the right pleural effusion confirmed the diagnosis of right upper lung adenocarcinoma with multiple rib and mediastinal lymph node metastases and right malignant pleural effusion.Individualized POEM was performed first to alleviate dysphagia,and the final diagnosis was changed to esophageal muscle metastasis arising from lung adenocarcinoma.After treatment,the patient could eat soft solid food and received multiple rounds of pembrolizumab-combination chemotherapy.The patient’s progression-free survival was approximately 16 months.Long stable disease was obtained during the 24-month follow-up.CONCLUSION The incidence of distal esophageal segmental spasms induced by muscular metastasis arising from lung adenocarcinoma is extremely low.Individualized POEM can effectively improve a patient’s nutritional status before subsequent chemotherapy can be combined with immune checkpoint inhibitors.

Clinicopathological features and medium-term outcomes of histologic variants of primary focal segmental glomerulosclerosis in adults:A retrospective study

BACKGROUND The Columbia classification identified five histological variants of focal segmental glomerulosclerosis(FSGS).The prognostic significance of these variants remains controversial.AIM To evaluate the relative frequency,clinicopathologic characteristics,and medium-term outcomes of FSGS variants at a single center in Pakistan.METHODS This retrospective study was conducted at the Department of Nephrology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan on all consecutive adults(≥16 years)with biopsy-proven primary FSGS from January 1995 to December 2017.Studied subjects were treated with steroids as a first-line therapy.The response rates,doubling of serum creatinine,and kidney failure(KF)with replacement therapy were compared between histological variants using ANOVA or Kruskal Wallis,and Chi-square tests as appropriate.Data were analyzed by SPSS version 22.0.P-value≤0.05 was considered significant.RESULTS A total of 401 patients were diagnosed with primary FSGS during the study period.Among these,352(87.7%)had a designated histological variant.The not otherwise specified(NOS)variant was the commonest,being found in 185(53.9%)patients,followed by the tip variant in 100(29.1%)patients.Collapsing(COL),cellular(CEL),and perihilar(PHI)variants were seen in 58(16.9%),6(1.5%),and 3(0.7%)patients,respectively.CEL and PHI variants were excluded from further analysis due to small patient numbers.The mean follow-up period was 36.5±29.2 months.Regarding response rates of variants,patients with TIP lesions achieved remission more frequently(59.5%)than patients with NOS(41.8%)and COL(24.52%)variants(P<0.001).The hazard ratio of complete response among patients with the COL variant was 0.163[95%confidence interval(CI):0.039-0.67]as compared to patients with NOS.The TIP variant showed a hazard ratio of 2.5(95%CI:1.61-3.89)for complete remission compared to the NOS variant.Overall,progressive KF was observed more frequently in patients with the COL variant,43.4%(P<0.001).Among these,24.53%of patients required kidney replacement therapy(P<0.001).The hazard ratio of doubling of serum creatinine among patients with the COL variant was 14.57(95%CI:1.87-113.49)as compared to patients with the TIP variant.CONCLUSION In conclusion,histological variants of FSGS are predictive of response to treatment with immunosuppressants and progressive KF in adults in our setup.

Numerical Simulation-Based Analysis of the Impact of Overloading on Segmentally Assembled Bridges

Segmentally assembled bridges are increasinglyfinding engineering applications in recent years due to their unique advantages,especially as urban viaducts.Vehicle loads are one of the most important variable loads acting on bridge structures.Accordingly,the influence of overloaded vehicles on existing assembled bridge structures is an urgent concern at present.This paper establishes thefinite element model of the segmentally assembled bridge based on ABAQUS software and analyzes the influence of vehicle overload on an assembled girder bridge struc-ture.First,afinite element model corresponding to the target bridge is established based on ABAQUS software,and the load is controlled to simulate vehicle movement in each area of the traveling zone at different times.Sec-ond,the key cross-sections of segmental girder bridges are monitored in real time based on the force character-istics of continuous girder bridges,and they are compared with the simulation results.Finally,a material damage ontology model is introduced,and the structural damage caused by different overloading rates is compared and analyzed.Results show that thefinite element modeling method is accurate by comparing with on-site measured data,and it is suitable for the numerical simulation of segmental girder bridges;Dynamic sensors installed at 1/4L,1/2L,and 3/4L of the segmental girder main beams could be used to identify the dynamic response of segmental girder bridges;The bottom plate of the segmental girder bridge is mostly damaged at the position where the length of the precast beam section changes and the midspan position.With the increase in load,damage in the direction of the bridge develops faster than that in the direction of the transverse bridge.Thefindings of this study can guide maintenance departments in the management and maintenance of bridges and vehicles.

Review of plasma exchange and rituximab for prevention of recurrent focal segmental glomerulosclerosis after a prior graft loss

BACKGROUND Focal segmental glomerulosclerosis(FSGS)often recurs after transplantation,leading to graft dysfunction and graft loss.Patients who have lost prior grafts due to recurrence are at particularly high risk of re-recurrence in subsequent grafts.Rituximab and plasma exchange have been used pre-emptively to prevent post-transplant recurrence.However,the efficacy of such preventative measures remains unclear.AIM To investigate the outcomes of preventative rituximab and plasma exchange for recurrent FSGS in transplant recipients after prior graft loss.METHODS We conducted a systematic review of 11 studies with 32 patients who had experienced prior graft loss due to post-transplant FSGS recurrence and were treated with either pre-emptive plasma exchange alone,rituximab alone,or a combination of both.RESULTS Overall,47%of the 32 patients experienced recurrence despite prophylactic treatment.Re-recurrence was seen in 25%(1/4)with pre-emptive rituximab alone,and 45%recurrence(9/20)with plasma exchange alone.Re-recurrence was noted in 63%with the use of combined plasma exchange and rituximab.CONCLUSION There is a paucity of available evidence in the literature to draw clear conclusions on the benefits of pre-emptive measures to prevent FSGS re-recurrence.The small sample sizes and variations in protocols call for larger and controlled studies to serve this patient population at high risk of recurrence and graft loss.

Clinical course and outcome of adult patients with primary focal segmental glomerulosclerosis with kidney function loss on presentation

BACKGROUND Kidney function loss or renal insufficiency indicated by elevated creatinine levels and/or an estimated glomerular filtration rate(eGFR)<60 mL/minute/1.73 m²at presentation in patients with primary focal segmental glomerulosclerosis(FSGS)is commonly seen as a poor prognostic marker for kidney survival.However,a pre>vious study from our center suggested this may be due to hemodynamic factors.AIM To observe the clinical and biochemical parameters,treatment response,kidney survival,and overall outcomes of adult patients with primary FSGS presenting with kidney function insufficiency.METHODS This retrospective observational study was conducted at the Department of Nephrology,Sindh Institute of Urology and Transplantation,Karachi,Pakistan,from January 1995 to December 2017.During this period,401 biopsy-proven primary FSGS patients were identified,of which 98(24.4%)presented with kidney function loss or renal insufficiency defined as eGFR<60 mL/minute/1.73 m²at presentation and were studied in detail.RESULTS Among the 98 patients with renal function loss on presentation,the mean age was 30.9 years±13.6 years with a male-to-female ratio of 2.5:1.The mean serum creatinine level was 2.2 mg/dL±1.3 mg/dL and mean eGFR 37.1 mL/minute/1.73 m2±12.8 mL/minute/1.73 m2.The mean 24-hour urinary protein excretion was 5.9 g/day±4.0 g/day,and the mean serum albumin was 2.1 g/dL±1.0 g/dL(median:1.5 g/dL).The mean systolic blood pressure(BP)was 132.7 mmHg±19.8 mmHg,and the mean diastolic BP was 87.4 mmHg±12.7 mmHg.Steroid treatment was given to 81(82.6%)of 98 patients for an average duration of 19.9 weeks±14.4 weeks,with a mean total steroid dose of 4.4 g±1.5 g.Treatment response showed that 20(24.6%)patients achieved complete remission,9(11.1%)achieved partial remission,and 52(64.1%)did not respond.The baseline eGFR was significantly lower in the non-responsive group(P=0.006).The distribution of FSGS variants was also significantly different among steroid-responsive and non-responsive groups(P=0.012).CONCLUSION Renal function loss in FSGS patients at presentation does not necessarily indicate irreversible kidney function loss and a significant number of patients respond to appropriate treatment of the underlying disease.

Analysis of the Effect of High-Dose Segmental Citrate Anticoagulation in High Flux Hemodialysis

Objective:To analyze the clinical effect of high-dose citrate in segmental extracorporeal anticoagulation for high-throughput hemodialysis.Methods:The subjects included in this study were admitted to the hospital for maintenance hemodialysis treatment from January 2021 to January 2023.All patients had a high risk of bleeding and received 4%trisodium citrate anticoagulant treatment,administered at a rate of 200 mL/h before and after the dialyzer.The anticoagulant effects achieved by the patients were observed and analyzed.Results:The total number of patients who received high-dose segmented citrate extracorporeal anticoagulation dialysis treatment was 50,with each patient undergoing 100 treatments.During the treatment,2 patients had to end the treatment early due to transmembrane pressure exceeding 30 mmHg and an increase in venous pressure exceeding 250 mmHg;the treatment times for these patients were 20 minutes and 200 minutes,respectively.The remaining patients successfully completed the 4-hour treatment.Blood pH and calcium ion concentration in the venous pot were monitored.It was observed that before dialysis,after 2 hours of dialysis,and at the end of dialysis,the blood pH of the patients remained within a relatively normal range.Although some patient levels changed after dialysis,they remained within the normal range.No adverse reactions(such as numbness of the limbs or convulsions)were observed during the anticoagulant treatment.Conclusion:Administering 4%trisodium citrate at a rate of 200 mL/h before and after the dialyzer achieves a good anticoagulant effect,maintains the patient’s blood gas levels within the normal range at the end of dialysis,and causes no adverse reactions.

Age-related driving mechanisms of retinal diseases and neuroprotection by transcription factor EB-targeted therapy

Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.

Successful emergency surgical intervention in acute non-STsegment elevation myocardial infarction with rupture:A case report

BACKGROUND The incidence of acute myocardial infarction(AMI)is rising,with cardiac rupture accounting for approximately 2%of deaths in patients with acute ST-segment elevation myocardial infarction(STEMI).Ventricular free wall rupture(FWR)occurs in approximately 2%of AMI patients and is notably rare in patients with non-STEMI.Types of cardiac rupture include left ventricular FWR,ventricular septal rupture,and papillary muscle rupture.The FWR usually leads to acute cardiac tamponade or electromechanical dissociation,where standard resuscitation efforts may not be effective.Ventricular septal rupture and papillary muscle rupture often result in refractory heart failure,with mortality rates over 50%,even with surgical or percutaneous repair options.CASE SUMMARY We present a rare case of an acute non-STEMI patient who suffered sudden FWR causing cardiac tamponade and loss of consciousness immediate before undergoing coronary angiography.Prompt resuscitation and emergency open-heart repair along with coronary artery bypass grafting resulted in successful patient recovery.CONCLUSION This case emphasizes the risks of AMI complications,shares a successful treatment scenario,and discusses measures to prevent such complications.

基于Segmental-DTW的无监督行为序列分割

行为序列分割是行为分析与识别中最初始、最基础的一个步骤.提出了一种无监督的行为序列分割算法,主要步骤包括:(1)采用等长有重叠的时间窗口对视频序列进行粗分割;(2)将粗分割的视频段两两作比较,通过Segmental-DTW算法分割出两个视频段中最相似的行为片断;(3)将行为片断的相似性转化为邻接图表示,通过图聚类方法对分割出的行为片断进行聚类.该算法采用了从粗到细的分割思想,能够准确地分割出视频序列中大量出现的行为的片断,并将相同行为的片断聚为一类.分割结果可以直接用于行为建模和识别.实验结果也表明了分割出的行为片断具有较好的代表性和有效性.

Middle segmental pancreatectomy: A safe and organ-preserving option for benign and low-grade malignant lesions

AIM: To study the feasibility and safety of middle segmental pancreatectomy (MSP) compared with pancreaticoduodenectomy (PD) and extended distal pancreatectomy (EDP). METHODS: We studied retrospectively 36 cases that underwent MSP, 44 patients who underwent PD, and 26 who underwent EDP with benign or low-grade malignant lesions in the mid-portion of the pancreas, between April 2003 and December 2009 in Ruijin Hospital. The perioperative outcomes and long-term outcomes of MSP were compared with those of EDP and PD. Periop-erative outcomes included operative time, intraoperative hemorrhage, transfusion, pancreatic fistula, intraabdominal abscess/infection, postoperative bleeding, reoperation, mortality, and postoperative hospital time. Long-term outcomes, including tumor recurrence, newonset diabetes mellitus (DM), and pancreatic exocrine insufficiency, were evaluated. RESULTS: Intraoperative hemorrhage was 316.1 ± 309.6, 852.2 ± 877.8 and 526.9 ± 414.5 mL for the MSP, PD and EDP groups, respectively (P < 0.05). The mean postoperative daily fasting blood glucose level was significantly lower in the MSP group than in the EDP group (6.3 ± 1.5 mmol/L vs 7.3 ± 1.5 mmol/L, P < 0.05). The rate of pancreatic fistula was higher in the MSP group than in the PD group (42% vs 20.5%, P = 0.039), all of the fistulas after MSP corresponded to grade A (9/15) or B (6/15) and were sealed following conservative treatment. There was no significant difference in the mean postoperative hospital stay between the MSP group and the other two groups. After a mean follow-up of 44 mo, no tumor recurrences were found, only one patient (2.8%) in the MSP group vs five (21.7%) in the EDP group developed new-onset insulin-dependent DM postoperatively (P = 0.029). Moreover, significantly fewer patients in the MSP group than in the PD (0% vs 33.3%, P < 0.001) and EDP (0% vs 21.7%, P = 0.007) required enzyme substitution. CONCLUSION: MSP is a safe and organ-preserving option for benign or low-grade malignant lesions in the neck and proximal body of the pancreas.

Segmental duodenectomy for gastrointestinal stromal tumor of the duodenum

AIM: To evaluate the results of segmental duodenectomy (SD) and pancreaticoduodenectomy (PD) for duodenal gastrointestinal stromal tumor (GIST) and help clinicians with surgical management. METHODS: All patients who underwent surgery for non-metastatic GIST of the duodenum in a single institution since 2000 were prospectively followed up. Seven patients (median age 51 years, range: 41-73 years) were enrolled: five underwent SD and two underwent PD. RESULTS: All the patients had a complete resection (R0), with no postoperative morbidity and mortality. Among the SD group, GIST was classified as low risk in two patients, intermediate risk in two, and high risk in one, according to the Fletcher scale, (vs two high risk patients in the PD group). With a median followup of 41 (18-85) mo, disease-free survival (DFS) rateswere 100% after SD and 0% after PD (P < 0.05). The median DFS was 13 mo in the PD group. CONCLUSION: Whenever associated with clear surgical margins, SD is a reliable and curative option for most duodenal GISTs, and is compatible with longterm DFS.

Cyclic performance and simplified pushover analyses of precast segmental concrete bridge columns with circular section

In recent years, precast segmental concrete bridge columns became prevalent because of the benefits of accelerated construction, low environmental impact, high quality and low life cycle costs. The lack of a detailed configuration and appropriate design procedure to ensure a comparable performance with monolithic construction has impeded this structural system from being widely used in areas of high seismicity. In this study, precast segmental bridge column cyclic loading tests were conducted to investigate the performance of unbonded post-tensioned segmental bridge columns. One monolithic and two precast segmental columns were tested. The preeast segmental column exhibited minor damage and small residual displacement after the maximum 7% cyclic drift; energy dissipation （ED） can be enhanced byadding ED bars. The experimental results were modeled by a simplified pushover method （SPOM）, as well as a fiber model （FIBM） finite element method. Forty-five cases of columns with different aspect ratios, axial load ratios and ED bar ratios were analyzed with the SPOM and FIBM, respectively. Using these parametric results, a simplified design method was suggested by regressive analysis. Satisfactory correlation was found between the experimental results and the simplified design method for preeast segmental columns with different design parameters.

SegHMC:一种基于Segmental HMM模型的顺式调控模块识别算法

顺式调控模块(Cis-regulatory module,CRM)在真核生物基因的转录调控中起着重要作用,识别顺式调控模块是当前计算生物学的一个重要课题.虽然当前有许多计算方法用于识别顺式调控模块,但识别准确率仍有待进一步提高.将顺式调控模块的多种特征信息结合在一起,有助于提高识别顺式调控模块的准确率.基于此,本文提出了一种识别顺式调控模块的算法Seg HMC(Segmental HMM model for discovery of cis-regulatory module).该算法建立了一种关于顺式调控模块识别问题的Segmental HMM模型,进一步扩展了顺式调控模块调控结构(或调控语法)的表示,不仅将顺式调控模块表示为模体(Motif)的组合,还进一步将模体共同出现的频率、模体顺序偏好以及顺式调控模块中相邻模体间的距离分布等特征引入到顺式调控模块的调控语法中.在模拟数据集和真实生物数据集上的实验结果表明,本文方法识别顺式调控模块的准确率显著优于当前的主要方法.

Isolated segmental,sectoral and right hepatic bile duct injuries

The treatment of isolated segmental, sectoral and right hepatic bile duct injuries is controversial. Nineteen patients were treated over a 26-year period. Group one was comprised of 4 patients in whom the injury was primarily repaired during the original surgery; 3 over a T-tube, 1 with a Roux-en-Y. These patients had an uneventful recovery. The second group consisted of 5 patients in whom the duct was ligated; 4 developed infection, 3 of which required drainage and biliary repair. Two patients had good long-term outcomes; the third developed a late anastomotic stricture requiring further surgery. The fourth patient developed a small bile leak and pain which resolved spontaneously. The fifth patient developed complications from which he died. The third group was comprised of 4 patients referred with biliary peritonitis; all underwent drainage and lavage, and developed biliary fistulae, 3 of which resolved spontaneously, 1 required Roux-en-γ repair, with favorable outcomes. The fourth group consisted of 6 patients with biliary fistulae. Two patients, both with an 8-wk history of a fistula, underwent Roux-en-γ repair. Two others also underwent a Roux-en-γ repair, as their fistulae showed no signs of closure. The remaining 2 patients had spontaneous closure of their biliary fistulae. A primary repair is a reasonable alternative to ligature of injured duct. Patients with ligated ducts may develop complications. Infected ducts require further surgery. Patients with biliary peritonitis must be treated with drainage and lavage. There is a 50% chance that a biliary fistula will close spontaneously. In cases where the biliary fistula does not close within 6 to 8 wk, a Roux-en-γ anastomosis should be considered.

Segmental ureteroileal conduit resection for the treatment of distal upper urinary tract recurrence of bladder cancer fol lowing cystectomy

Segmental ureterectomy is less invasive than radical nephroureterectomy and results in nephron preservation and satisfactory tumor control.This study was to determine the feasibility of segmental ureteroileal conduit resection(SUICR) for patients with distal upper urinary tract recurrence of bladder cancer following radical cystectomy.Four patients with high-grade distal upper urinary tract recurrence underwent SUICR 15-108 months after radical cystectomy.The surgical technique details of SUICR,operative results,and follow-up outcomes are reported.The median operation time was 280 min,and estimated blood loss was less than 100 ml One patient suffered from ileus 5 days after surgery and was managed conservatively.Histopathologic evaluation showed high-grade stages pTa-pT1 diseases for these patients,and ureteral margins were all negative.No patient suffered from tumor recurrence,with a median follow-up of 39 months.SUICR preserved the ipsilateral renal unit and conformed to oncological principles during surgery.The oncological outcome was satisfactory for these properly selected patients.This technique provides a valid alternative to nephroureterectomy for patients with imperative indications and high-grade upper urinary tract recurrence of bladder cancer following radical cystectomy.

Modeling and cyclic behavior of segmental bridge column connected with shape memory alloy bars

This paper examines the quasi-static cyclic behavior, lateral strength and equivalent damping capacities of a system of post-tensioned segmental bridge columns tied with large diameter martensitic Shape Memory Alloy （SMA） link-bars. Moment-curvature constitutive relationships are formulated and analysis tools are developed for the PT column, including a modified four-spring model prepared for the SMA bars. The suggested system is exemplified using a column with an aspect ratio of 7.5 and twelve 36.5 mm diameter NiTi martensitic SMA bars. A post-tensioning force of 40% to 60% of the tendon yield strength is applied in order to obtain a self re-centering system, considering the residual stress of the martensitie SMA bars. The cyclic response results show that the lateral strength remains consistently around 10% of the total vertical load and the equivalent viscous damping ratios reach 10%-12% of critical. When large diameter NiTi superelastic SMA bars are incorporated into the column system, the cyclic response varies substantially. The creep behavior of the superelastic SMA bar is accounted for since it affects the re-centering capability of the column. Two examples are presented to emphasize the modeling sensitivities for these special bars and quantify their cyclic behavior effects within the column assembly.

Diagnosis and management of fibromuscular dysplasia and segmental arterial mediolysis in gastroenterology field: A mini-review

The vascular diseases including aneurysm, occlusion, and thromboses in the mesenteric lesions could cause severe symptoms and appropriate diagnosis and treatment are essential for managing patients. With the development and improvement of imaging modalities, diagnostic frequency of these vascular diseases in abdominal lesions is increasing even with the small changes in the vasculatures. Among various vascular diseases, fibromuscular dysplasia(FMD) and segmental arterial mediolysis(SAM) are noninflammatory, nonatherosclerotic arterial diseases which need to be diagnosed urgently because these diseases could affect various organs and be lethal if the appropriate management is not provided. However, because FMD and SAM are rare, the cause, prevalence, clinical characteristics including the symptoms, findings in the imaging studies, pathological findings, management, and prognoses have not been systematically summarized. Therefore, there have been neither standard diagnostic criteria nor therapeutic methodologies established, to date. To systematically summarize the information and to compare these disease entities, we have summarized the characteristics of FMD and SAM in the gastroenterological regions by reviewing the cases reported thus far. The information summarized will be helpful for physicians treating these patients in an emergency care unit and for the differential diagnosis of other diseases showing severe abdominal pain.

Development of ecoregion-based merchantable volume systems for Pinus brutia Ten. and Pinus nigra Arnold. in southern Turkey

Estimating individual tree volume is one of the essential building blocks in forest growth and yield models. Ecologically based taper equations provide accurate vol- ume predictions and allow classification by mer- chantable sizes, assisting in sustainable forest management. In the present study, ecoregion-based compatible volume systems for brutian pine and black pine in the three ecoregions of southern Turkey were developed. Several well-known taper functions were evaluated. A second- order continuous-time autoregressive error structure was used to correct the inherent autocorrelation in the hierar- chical data, allowing the model to be applied to irregularly spaced and unbalanced data. The compatible segmented model of Fang et al. （For Sci 46：1-12, 2000） best described the experimental data. It is therefore recommended for estimating diameter at a specific height, height to a specific diameter, merchantable volume, and total volume for the three ecoregions and two species analyzed. The nonlinearextra sum of squares method indicated differences in ecoregion and tree-specific taper functions. A different taper function should therefore be used for each pine spe- cies and ecoregion in southern Turkey. Using ecoregion- specific taper equations allows making more robust esti- mations and, therefore, will enhance the accuracy of diameter at different heights and volume predictions.

Compatible taper and stem volume equations for Larix kaempferi(Japanese larch) species of South Korea

In this study, compatible taper and stem volume equations were developed for Larix kaempferi species of South Korea. The dataset was split into two groups： 80% of the data were used in model fitting and the remaining 2o% were used for validation. The compatible MB76 equations were used to predict the diameter outside bark to a specific height, the height to a specific diameter and the stem volume of the species. The result of the stem volume analysis was compared with the existing stem volume model of Larix kaempferi species of South Korea which was developed by the Korea Forest Research Institute and with a simple volume model that was developed with fitting dataset in this study. The compatible model provided accurate prediction of the total stem volume when compared to the existing stem volume model and with a simple volume model. It is concluded that the compatible taper and stem volume equations are more convenient to use and therefore it is recommended to be applied in the Larix kaempferi species of South Korea.

Carcinoma of the middle bile duct:Is bile duct segmental resection appropriate?

AIM:To compare survival between bile duct segmental resection(BDSR)and pancreaticoduodenectomy(PD) for treating distal bile duct cancers. METHODS:Retrospective analysis was conducted for 45 patients in a BDSR group and for 149 patients in a PD group. RESULTS:The T-stage(P<0.001),lymph node invasion (P=0.010)and tumor differentiation(P=0.005)were significant prognostic factors in the BDSR group.The 3-and 5-year overall survival rates for the BDSR group and PD group were 51.7%and 36.6%,respectively and 46.0%and 38.1%,respectively(P=0.099).The BDSR group and PD group did not show any significant difference in survival when this was adjusted for the TNM stage.The 3-and 5-year survival rates were: stageⅠa[BDSR(100.0%and 100.0%)vs PD(76.9% and 68.4%)(P=0.226)];stageⅠb[BDSR(55.8% and 32.6%)vs PD(59.3%and 59.3%)(P=0.942)]; stageⅡb[BDSR(19.2%and 19.2%)vs PD(31.9%and 14.2%)(P=0.669)]. CONCLUSION:BDSR can be justified as an alternative radical operation for patients with middle bile duct inselected patients with no adjacent organ invasion and resection margin is negative.