Comparing Balloon Dilation to Non-Balloon Dilation for Access in Ultrasound-Guided Percutaneous Nephrolithotomy: A Systematic Review and Meta-Analysis.

PURPOSE: This study aims to evaluate the safety and efficacy of ultrasound-guided balloon dilation compared to non-balloon dilation for percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: A systematic review and meta-analysis were conducted by searching PubMed, EMBASE, and the Cochrane Library. Results were filtered using predefined inclusion and exclusion criteria as described and meta-analysis was performed using Review Manager 5.4 software. RESULTS: A total of six studies involving 1189 patients who underwent PCNL were included. The meta-analysis results demonstrated that compared to non-balloon dilation, balloon dilation was associated with reduced haemoglobin drop [mean difference (MD) = -0.26, 95% CI = -0.40 ~ -0.12, P = 0.0002], decreased transfusion rate [odds ratio (OR) = 0.47, 95% CI = 0.24 ~ 0.92, P = 0.03], shorter tract establishment time (MD = -1.30, 95% CI = -1.87 ~ -0.72, P < 0.0001) and shorter operation time (MD = -5.23, 95% CI = -10.19 ~ -0.27, P = 0.04). CONCLUSIONS: Overall, ultrasound-guided balloon dilatation offered several advantages in PCNL procedures. It facilitated faster access establishment, as evidenced by shorter access creation time. Additionally, it reduced the risk of kidney injury by minimizing postoperative haemoglobin drop and decreasing the need for transfusions. Moreover, it enhanced the efficiency of surgery by reducing the operation time. However, it is important to note that the quality of some included studies was subpar, as they did not adequately control for confounding factors that may affect the outcomes. Therefore, further research is necessary to validate and strengthen these findings.

Insight into Interfacial Polarization for Enhancing Piezoelectricity in Ferroelectric Nanocomposites.

The interfacial effect is widely used to optimize the properties of ferroelectric nanocomposites, however, there is still a lack of direct evidence to understand its underlying mechanisms limited by the nano size and complex structures. Here, taking piezoelectricity, for example, the mechanism of interfacial polarization in barium titanate/poly(vinylidene fluoride-ran-trifluoroethylene) (BTO/P(VDF-TrFE)) nanocomposite is revealed at multiple scales by combining Kelvin probe force microscope (KPFM) with theoretical stimulation. The results prove that the mismatch of permittivity between matrix and filler leads to the accumulation of charges, which in turn induces local polarization in the interfacial region, and thus can promote piezoelectricity independently. Furthermore, the strategy of interfacial polarization to enhance piezoelectricity is extended and validated in other two similar nanocomposites. This work uncovers the mechanism of interfacial polarization and paves newfangled insights to boost performances in ferroelectric nanocomposites.

Recent Advances in Photochemical Asymmetric Three-Component Reactions.

Over the past decades, asymmetric photochemical synthesis has garnered significant attention for its sustainability and unique ability to generate enantio-enriched molecules through distinct reaction pathways. Photochemical asymmetric three-component reactions have demonstrated significant potential for the rapid construction of chiral compounds with molecular diversity and complexity. However, noteworthy challenges persist, including the participation of high-energy intermediates such as radical species, difficulties in precise control of stereoselectivity, and the presence of competing background and side reactions. Recent breakthroughs have led to the development of sophisticated strategies in this field. This review explores the intricate mechanisms, synthetic applications, and limitations of these methods. We anticipate that it will contribute towards advancing asymmetric catalysis, photochemical synthesis, and green chemistry.

Risk factors associated with 31-day unplanned hospital readmission in newborns: a systematic review.

The purpose of this study is to synthesize evidence on risk factors associated with newborn 31-day unplanned hospital readmissions (UHRs). A systematic review was conducted searching CINAHL, EMBASE (Ovid), and MEDLINE from January 1st 2000 to 30th June 2021. Studies examining unplanned readmissions of newborns within 31 days of discharge following the initial hospitalization at the time of their birth were included. Characteristics of the included studies examined variables and statistically significant risk factors were extracted from the inclusion studies. Extracted risk factors could not be pooled statistically due to the heterogeneity of the included studies. Data were synthesized using content analysis and presented in narrative and tabular form. Twenty-eight studies met the eligibility criteria, and 17 significant risk factors were extracted from the included studies. The most frequently cited risk factors associated with newborn readmissions were gestational age, postnatal length of stay, neonatal comorbidity, and feeding methods. The most frequently cited maternal-related risk factors which contributed to newborn readmissions were parity, race/ethnicity, and complications in pregnancy and/or perinatal period. CONCLUSION: This systematic review identified a complex and diverse range of risk factors associated with 31-day UHR in newborn. Six of the 17 extracted risk factors were consistently cited by studies. Four factors were maternal (primiparous, mother being Asian, vaginal delivery, maternal complications), and two factors were neonatal (male infant and neonatal comorbidities). Implementation of evidence-based clinical practice guidelines for inpatient care and individualized hospital-to-home transition plans, including transition checklists and discharge readiness assessments, are recommended to reduce newborn UHRs. WHAT IS KNOWN: • Attempts have been made to identify risk factors associated with newborn UHRs; however, the results are inconsistent. WHAT IS NEW: • Six consistently cited risk factors related to newborn 31-day UHRs. Four maternal factors (primiparous, mother being Asian, vaginal delivery, maternal complications) and 2 neonatal factors (male infant and neonatal comorbidities). • The importance of discharge readiness assessment, including newborn clinical fitness for discharge and parental readiness for discharge. Future research is warranted to establish standardised maternal and newborn-related variables which healthcare providers can utilize to identify newborns at greater risk of UHRs and enable comparison of research findings.

Vertical-MXene based micro-supercapacitors with thickness-independent capacitance.

MXenes have shown great potential as an emerging two-dimensional (2D) material for micro-supercapacitors (MSCs) due to their high conductivity, rich surface chemistry, and high capacity. However, MXene sheets inherently tend to lay flat on the substrate during film formation to assemble into compact stacked structures, which hinders ion accessibility and prolongs ion transport paths, leading to highly dependent electrochemical properties on the thickness of the film. Here, we demonstrate a vertically aligned Ti3C2Tx MXene based micro-supercapacitor with an excellent electrochemical performance by a liquid nitrogen-assisted freeze-drying method. The vertical arrangement of the 2D MXene sheets allows for directional ion transport, enabling the vertical-MXene based MSCs to exhibit thickness-independent electrochemical properties even in thick films. In addition, the MSCs displayed a high areal capacitance of 87 mF cm-2 at 10 mV s-1 along with an excellent stability of ∼87.4% after 10 000 charge-discharge cycles. Furthermore, the vertical-MXene approach proposed here is scalable and can be extended to other systems involving directional transport.

Declaration: Novel SLC3A1 mutation in a cystinuria patient with xanthine stones: a case report.

BACKGROUND: Cystinuria and xanthinuria are both rare genetic diseases involving urinary calculi. However, cases combining these two disorders have not yet been reported. CASE PRESENTATION: In this study, we report a case of cystinuria with xanthine stones and hyperuricemia. The 23-year-old male patient was diagnosed with kidney and ureteral stones, solitary functioning kidney and hyperuricemia after admission to the hospital. The stones were removed by surgery and found to be composed of xanthine. CONCLUSION: Genetic testing by next-generation sequencing technology showed that the patient carried the homozygous nonsense mutation c.1113 C> A (p.Tyr371*) in the SLC3A1 gene, which was judged to be a functionally pathogenic variant. Sanger sequencing revealed that the patient's parents carried this heterozygous mutation, which is a pathogenic variant that can cause cystinuria. The 24-h urine metabolism analysis showed that the cystine content was 644 mg (<320 mg/24 h), indicating that the patient had cystinuria, consistent with the genetic test results. This case shows that cystinuria and xanthine stones can occur simultaneously, and provides evidence of a possible connection between the two conditions. Furthermore, our findings demonstrate the potential value of genetic testing using next-generation sequencing to effectively assist in the clinical diagnosis and treatment of patients with urinary calculi.

High perirenal fat thickness predicts a greater risk of recurrence in Chinese patients with unilateral nephrolithiasis.

INTRODUCTION: The aim of this study was to evaluate the association between recurrence-free survival (RFS) and perirenal fat thickness (PFT) in a cohort of Chinese population with unilateral nephrolithiasis. METHODS: We retrospectively reviewed the medical records of 81 patients with unilateral nephrolithiasis in our center from January 2019 to June 2019. PFT measured on computed tomography (CT) scans was evaluated. Kaplan-Meier curves and log-rank tests were used to assess significant differences in RSF between high-PFT and low-PFT groups within sexes. Univariable and multivariable Cox regression analyses were used to evaluate the potential risk factors for renal stone recurrence. RESULTS: High PFT was significantly associated with high BMI and hyperlipidemia (p = .003 and.047, respectively). The PFT of stone-bearing kidney was significantly greater than PFT of non-stone-bearing kidney (0.77 ± 0.60 cm vs. 0.67 ± 0.58 cm, p = .002) . During the follow-up periods (median 31 months), 21 (25.9%) patients experienced ipsilateral renal stone recurrence. In addition, Kaplan-Meier survival curves showed that patients with low PFT had a significant better RFS than those with high PFT (p = .012). In the univariable Cox analyses, male sex and high PFT were significantly associated with a poor RFS (p = .042 and .018, respectively). Moreover, both male sex and high PFT retained significance in the multivariable analyses (p = .045 and .020, respectively). CONCLUSIONS: Our findings suggested that PFT is a noninvasive and feasible parameter, which may help in the risk stratification of renal stone recurrence in the follow-up periods.

Air-Stable Conductive Polymer Ink for Printed Wearable Micro-Supercapacitors.

Printed electronics are expected to facilitate the widespread distributed wearable electronics in the era of the Internet of things. However, developing cheap and stable electrode inks remains a significant challenge in the printed electronics industry and academic community. Here, overcoming the weak hydrophilicity of polyaniline, a low-cost, easy-fabricating, and air-stable conducting polymer (CP) ink is devised through a facile assemble-disperse strategy delivering a high conductivity in the order of 10-2 S cm-1 along with a remarkable specific capacitance of 386.9 F g-1 at 0.5 A g-1 (dehydrated state). The additive-free CP ink is directly employed to print wearable micro-supercapacitors (MSCs) via the spray-coating method, which deliver a high areal capacitance (96.6 mF cm-2 ) and volumetric capacitance (26.0 F cm-3 ), outperforming most state-of-the-art CP-based supercapacitors. This work paves a new approach for achieving scalable MSCs, thus rendering a cost-effective, environmentally friendly, and pervasive energy solution for next-generation distributed electronics.

Retrograde en bloc resection for non-muscle invasive bladder tumor can reduce the risk of seeding cancer cells into the peripheral circulation.

OBJECTIVE: To ascertain whether en bloc resection could reduce the risk of seeding cancer cells into the circulation during the resection of non-muscle invasive bladder cancer (NMIBC). METHODS: Patients with primary NMIBC were enrolled in this prospective study from October 2017 to May 2018. Patients were allocated to receive conventional transurethral resection of the bladder (TURB) or retrograde en bloc resection technique of the bladder tumor (RERBT). Blood samples (1 ml) for circulating tumor cell (CTC) enumeration were drawn from the peripheral vein prior to resection (PV1), immediately after resection of the tumor base (PV2), and at 12 h after resection (PV3). Intra-group comparisons of the changes in the number of CTCs identified among the PV1, PV2, and PV3 blood samples were performed in each group. RESULTS: A total of 21 patients (12 in the RERBT group and 9 in the TURB group) were recruited. For patients receiving TURB, the level of CTCs identified in PV3 was significantly higher than that in PV1 (p = 0.047). However, there was no significant difference in CTC counts before and after resection in the RERBT group. CONCLUSION: RERBT did not increase the number of tumor cells in the bloodstream.

[Effects of PI3K/Akt-eNOS signaling pathway on total flavones in Clematis filamentosa post-conditioning alleviated of myocardial ischemia-reperfusion injury in rats].

The aim of this paper was to study the effect of total flavones of Clematis filamentosa Dunn(TFCD) post-conditioning against myocardial ischemia-reperfusion injury (MIRI) and the role of PI3K/Akt-eNOS signaling pathway. Forty male SD rats were divided randomly into five groups: Sham group, model group (I/R), TFCD post-conditioning group (TFCD), TFCD post-condition-ing+LY294002 (a PI3K/Akt signaling pathway inhibitor) group (TFCD+LY), and LY294002 group (LY). At the end of reperfusion, hemodynamic parameters were recorded, morphology changes of myocardial tissue were evaluated by using HE staining, and myocardial infarct size were observed, blood samples were obtained to determine plasma activation of lactate dehydrogenase (LDH), creatine kinase (CK) nitric oxide (NO), endothelial nitric oxide synthase (eNOS), superoxide dismutase (SOD), maleic dialdehyde (MDA) and glutathione peroxidase (GSH-Px). The expressions of Akt, p-Akt, eNOS and p-eNOS proteins were assessed by using Western blot, and eNOS and inducible nitric oxide synthase (iNOS) mRNA was measured by RT-PCR. The results showed that, compared with the model group, TFCD post-conditioning remarkably improved hemodynamics function and myocardial structure, reduced myocardial infarct size and enhanced the contents of NO, eNOS, SOD and GSH-Px, and decreased the contents of LDH, CK and MDA, increased the levels of phosphorylation of Akt and eNOS protein expression, eNOS and iNOS mRNA expression significantly(P＜0.05 or P＜0.01). These effects were inhibited by LY294002, a blocker of PI3K/Akt signaling pathway. The above experiments indicated that TFCD post-conditioning could significantly reduce MIRI in rats, the mechanism of which may be associated with increasing antioxidation, scavenging oxygen free radicals, regulating NO generation and activating PI3K/Akt-eNOS signaling pathway.

Gross Hematuria Is More Common in Male and Older Patients with Renal Tuberculosis in China: A Single-Center 15-Year Clinical Experience.

OBJECTIVES: This study aimed to investigate the clinical features of renal tuberculosis and identify the age- and gender-related differences. METHODS: A total of 419 patients at the Peking University First Hospital from January 2000 to July 2015 were retrospectively reviewed. Data on demographic characteristics, clinical presentation, complications, laboratory results, radiologic imaging, surgical procedures, and pathology features were collected and compared between genders and 3 different age groups (under 40 years, 41-60, years and over 60 years). RESULTS: The most common local presentations were lower urinary tract symptoms (65.2%), flank pain (37.9%), and gross hematuria (26.3%). Constitutional symptoms were also observed in 38.9% of the patients. Gross hematuria was more common in male patients (32.2%) and older patients (45.5%). Flank pain was more common in female patients (43.6%). Patients younger than 40 years of age had lower frequencies of calcification of the urinary tract (22.2%) and kidney atrophy (4.2%) in CT. In the postoperative pathological reports, atrophy (35.9%) and fibrosis (38.5%) were found to be significantly more common in older patients. CONCLUSIONS: While gross hematuria is more prevalent in older patients and male patients, flank pain is more common in female patients. Radiological and pathological features including calcification of the urinary tract, fibrosis, and kidney atrophy are more common in older patients.

MXene-Based Micro-Supercapacitors: Ink Rheology, Microelectrode Design and Integrated System.

MXenes have shown great potential for micro-supercapacitors (MSCs) due to the high metallic conductivity, tunable interlayer spacing and intercalation pseudocapacitance. In particular, the negative surface charge and high hydrophilicity of MXenes make them suitable for various solution processing strategies. Nevertheless, a comprehensive review of solution processing of MXene MSCs has not been conducted. In this review, we present a comprehensive summary of the state-of-the-art of MXene MSCs in terms of ink rheology, microelectrode design and integrated system. The ink formulation and rheological behavior of MXenes for different solution processing strategies, which are essential for high quality printed/coated films, are presented. The effects of MXene and its compounds, 3D electrode structure, and asymmetric design on the electrochemical properties of MXene MSCs are discussed in detail. Equally important, we summarize the integrated system and intelligent applications of MXene MSCs and present the current challenges and prospects for the development of high-performance MXene MSCs.

A Modulation Method for Tunnel Magnetoresistance Current Sensors Noise Suppression.

To mitigate the impact of low-frequency noise from the tunnel magnetoresistance (TMR) current sensor and ambient stray magnetic fields on weak current detection accuracy, we propose a high-resolution modulation-demodulation test method. This method modulates and demodulates the measurement signal, shifting low-frequency noise to the high-frequency band for effective filtering, thereby isolating the target signal from the noise. In this study, we developed a Simulink model for the TMR current sensor modulation-demodulation test method. Practical time-domain and frequency-domain tests of the developed high-resolution modulation-demodulation method revealed that the TMR current sensor exhibits a nonlinearity as low as 0.045%, an enhanced signal-to-noise ratio (SNR) of 77 dB, and a heightened resolution of 100 nA. The findings indicate that this modulation-demodulation test method effectively reduces the impact of low-frequency noise on TMR current sensors and can be extended to other types of resistive devices.

Identification of particle distribution pattern in vertical profile via unmanned aerial vehicles observation.

Below the boundary layer, the air pollutants have been confirmed to present the decreasing trend with the height in most situaitons. However, the disperiosn rate of air pollutants in the vertical profile is rarely investigated in detail, especially through in-situ measurement. With this consideration, we employed an unmanned aerial vehicle equipped with portable monitoring equipments to scrutinize the vertical distribution of PM2.5. Based on the original data, we found that PM2.5 concentration decreases gradually with altitude below the boundary layer and demonstrated an obvious linear correlation. Therefore, the vertical distribution of PM2.5 was quantified by representing the distribution of PM2.5 with the slope of PM2.5 vertical distribution. We used backward trajectories to reveal the causes of outliers (PM2.5 increasing with altitude), and found that PM2.5 in the high altitude came from the southwest. Besides, the relationship between the vertical distribution of PM2.5 and various meteorological factors was investigated using stepwise regression analysis. The results show that the four meteorological factors most strongly correlated with the slope values are: (a) the difference in relative humidity between the ground and the air; (b) the difference in temperature between the ground and the air; (c) the height of the boundary layer; and (d) the wind speed. The slope values increase with increasing the difference in relative humidity between ground and air and the difference in temperature between the ground and the air, and decrease with increasing boundary layer height and wind speed. According to the Random Forest calculations, the ground-to-air relative humidity difference is the most important at 0.718; the wind speed is the least important at 0.053; and the ground-to-air temperature difference and boundary layer height are 0.140 and 0.088, respectively.

[Epidemiology and clinical features of renal tuberculosis: 239 cases report].

OBJECTIVE: To study the changes in the status of genitourinary tuberculosis, especially in renal tuberculosis. METHODS: In the study, 239 cases of renal tuberculosis from 2000 to 2010 were retrospectively reviewed. The patients with 3 or more than 3 kinds of common clinical manifestations of genitourinary tuberculosis were regarded as typical group (145 cases), and otherwise, as atypical group (94 cases). RESULTS: The cases of renal tuberculosis constituted 0.89% of the urological inpatients in a duration of 11 years from 2000 to 2010. The incidence rates were higher in the 40-60 years old patients (45.61%). 48% of the patients were farmers or the unemployed. The most common clinical manifestations included frequency (151 cases), urgency (124 cases), odynuria (120 cases), flank pain (97 cases), and hematuria (76 cases). However, flank pain (34.04%) turned into the main complaint of the atypical group. We found that 125 cases had a history of pulmonary tuberculosis or an abnormal chest radiography, 30 patients were diagnosed as contracted bladder (typical group/atypical group: 26/4, P<0.05), and 20 patients (8.4%) were diagnosed as contralateral hydronephrosis. And 198 cases were examined by acid-fast stain, with a positive diagnostic rate of 47.98%. Also 202 cases of the 205 patients who had an ultrasonography had an abnormal outcome and 135 cases of them were definitively diagnosed. Surgical treatments were performed among almost all the patients, while 21 cases only had antituberculosis drugs. CONCLUSION: Socio-economic issues still affect the status of genitourinary tuberculosis. The history of pulmonary tuberculosis or an abnormal outcome of chest radiography can provide an important clue during the diagnostic process. Acid-fast stain and ultrasonography remain as effective screening tests. Though the treatment with antituberculosis drugs has become the "mainstream", the surgical treatment is needed for advanced renal tuberculosis.

[Multiple urethral metastases from prostate adenocarcinoma after radical prostatectomy: a case report and literature review].

OBJECTIVE: To investigate the mechanism and management of multiple urethral metastases from prostate adenocarcinoma after radical prostatectomy. METHODS: We summed up the experience in the management of a case of multiple urethral metastases from prostate adenocarcinoma after radical prostatectomy and reviewed relevant literature. The patient was a 79-year-old male, who had received radical prostatectomy for prostate adenocarcinoma 13 years before, and presented with macrohematuria and dysuria in the past 2 weeks. A nodule (1.0 x 0.5 cm) was found in the urethral meatus. Cystourethroscopy revealed multiple tumors in the urethra and biopsy indicated them to be metastases from prostate adenocarcinoma. The preoperative level of PSA was 3.01 microg/L. As treatment, we performed radical urethrectomy and cystostomy. RESULTS: Postoperative pathology showed multiple metastases of prostate adenocarcinoma to the urethra, involving the urethral sphincter and corpus spongiosum. Immunohistochemistry revealed PSA (+), PsAP(+), AR(+) and CK 7(-). The surgical margin was negative. The patient recovered well postoperatively, with a PSA level of 1.00 microg/L. CONCLUSION: Urethral metastasis of prostate adenocarcinoma after radical prostatectomy is rarely seen clinically. For the treatment of multiple urethral metastases, surgery is the first choice and radical urethrectomy is an appropriate management.

A lightweight ship target detection model based on improved YOLOv5s algorithm.

Real-time and accurate detection of ships plays a vital role in ensuring navigation safety and ship supervision. Aiming at the problems of large parameters, large computation quantity, poor real-time performance, and high requirements for memory and computing power of the current ship detection model, this paper proposes a ship target detection algorithm MC-YOLOv5s based on YOLOv5s. First, the MobileNetV3-Small lightweight network is used to replace the original feature extraction backbone network of YOLOv5s to improve the detection speed of the algorithm. And then, a more efficient CNeB is designed based on the ConvNeXt-Block module of the ConvNeXt network to replace the original feature fusion module of YOLOv5s, which improves the spatial interaction ability of feature information and further reduces the complexity of the model. The experimental results obtained from the training and verification of the MC-YOLOv5s algorithm show that, compared with the original YOLOv5s algorithm, MC-YOLOv5s reduces the number of parameters by 6.98 MB and increases the mAP by about 3.4%. Even compared with other lightweight detection models, the improved model proposed in this paper still has better detection performance. The MC-YOLOv5s has been verified in the ship visual inspection and has great application potential. The code and models are publicly available at https://github.com/sakura994479727/datas.

Biodegradable cotton fiber-based piezoresistive textiles for wearable biomonitoring.

Electronic textiles are fundamentally changing the way we live. However, the inability to effectively recycle them is a considerable burden to the environment. In this study, we developed a cotton fiber-based piezoresistive textile (CF p-textile) for biomonitoring which is biocompatible, biodegradable, and environmentally friendly. These CF p-textiles were fabricated using a scalable dip-coating method to adhere MXene flakes to porous cotton cellulose fibers. The adhesion is made stronger by strong hydrogen bonding between MXene flakes and hierarchically porous cotton cellulose fibers. This cotton-fiber system provides a high sensitivity of 17.73 kPa-1 in a wide pressure range (100 Pa-30 kPa), a 2 Pa subtle pressure detection limit, fast response/recovery time (80/40 ms), and good cycle stability (over 5, 000 cycles). With its compelling sensing performance, the CF p-textile can detect various human biomechanical activities, including pulsation, muscle movement, and swallowing, while still being comfortable to wear. Moreover, the cotton cellulose is decomposed into low-molecular weight cellulose or glucose as a result of the 1,4-glycosidic bond breakage when exposed to acid or during natural degradation, which allows the electronic textile to be biodegradable. This work offers an ecologically-benign, cost-effective and facile approach to fabricating high-performance wearable bioelectronics.

Nickel-Catalyzed Chemo- and Regioselective Benzylarylation of Unactivated Alkenes with o-Bromobenzyl Chlorides.

Chemo- and regioselectively nickel-catalyzed reductive benzylarylation of unactivated alkenes with o-bromobenzyl chlorides is disclosed herein, in which electrophiles participate through a single-component double-site approach. Moreover, its utility is underscored by the concise synthesis of bioactive Indane compounds and postreaction functionalizations leading to structurally diverse scaffolds. Preliminary mechanistic investigations suggest a radical chain reaction mechanism.

Pose-invariant matching for non-rigid 3D models using Isomap.

The wide usage of 3D mesh models greatly increases the importance of an effective matching algorithm for them. In this paper, we propose a novel 3D model matching algorithm. Firstly, vertices on the input 3D mesh models are mapped to 1D space by employing Isomap. A pose-invariant feature set is then constructed from the vertices in 1D space. Finally, the similarity between any two 3D models can be computed by comparing their feature sets. Experimental results show that the algorithm is not only invariant to translation, rotation, scaling, but also invariant to different poses of 3D models. Additionally, the algorithm is robust to noise.