Search

Abstract Background Cervical and upper thoracic esophageal cancer (ESCA) presents treatment challenges due to limited clinical evidence. This multi-center study (ChC&UES) explores radical radio(chemo)therapy efficacy and safety, especially focusing on radiation dose. Method We retrospectively analyzed clinical data from 1,422 cases across 8 medical centers. According to the radiation dose for primary gross tumor, patients were divided into standard dose radiotherapy (SD, 50–55 Gy) or high dose (HD, > 55 Gy) radiotherapy. HD was further subdivided into conventional- high-dose group (HD-conventional, 55–63 Gy) and ultra-high-dose group (HD-ultra, ≥ 63 Gy). Primary outcome was Overall Survival (OS). Results The median OS was 33.0 months (95% CI: 29.401–36.521) in the whole cohort. Compared with SD, HD shown significant improved survival in cervical ESCA in Kaplan-Meier (P = 0.029) and cox multivariate regression analysis (P = 0.024) while shown comparable survival in upper thoracic ESCA (P = 0.735). No significant difference existed between HD-conventional and HD-ultra in cervical (P = 0.976) and upper thoracic (P = 0.610) ESCA. Incidences of radiation esophagitis and pneumonia from HD were comparable to SD (P = 0.097, 0.240), while myosuppression risk was higher(P = 0.039). The Bonferroni method revealed that, for both cervical and upper thoracic ESCA, HD-ultra enhance the objective response rate (ORR) compared to SD (P

According to General Relativity Theory (GRT), by comparing the frequencies between two precise clocks at two different stations, the gravity potential (geopotential) difference between the two stations can be determined due to the gravity frequency shift effect. Here, we conduct a clock-transportation experiment for measuring geopotential differences based on frequency comparisons via satellite links between two remote hydrogen atomic clocks. Based on the net frequency shift between the two clocks in two different periods, the geopotential difference between stations of the Beijing 203 Institute Laboratory (BIL) and Luojiashan Time-frequency Station (LTS) is determined. Comparisons show that the experimental result deviated from the reference of Earth gravity model EGM2008 result by (38.5[Formula: see text]45.9) m in Orthometric Height (OH). The results are consistent with the frequency stabilities of the hydrogen clocks (at the level of [Formula: see text]) used in the experiment. With the rapid development of time and frequency science and technology, the approach discussed in this study for measuring the geopotential is prospective and thus, could have broad applications.

ABSTRACTThe gravitational curvatures (GC, the third-order derivatives of the gravitational potential) in gravity field modeling are gaining increased interest in geosciences. The crustal effects of the GC and Moho variation sensed by the GC are not fully evaluated for the current study. In this contribution, the effects of the GC induced by topographic and anomalous crustal masses are investigated based on ETOPO1 and CRUST1.0 models using the tesseroids. By adopting the gravitational stripping correction, the residual GC sensed by the CRUST1.0 Moho depths are presented globally to examine whether the GC can sense crustal mass anomalies at the satellite altitude of 260 km . The spatial analysis using the Pearson correlations coefficient (PCC) between the residual GC and the CRUST1.0 Moho depths is performed. Among the 10 residual GC functionals, the PCC value of the residual radial-radial-radial component [Formula: see text] is largest with 0.31, where this value is highly dependent on the spectral content removed from the EGM2008, e.g. signals assumed to relate to deeper mass anomalies. Numerical experiments show that with the increased order of the derivatives up to third-order, the fineness level of different global Moho sensed crustal mass anomalies increases correspondingly. Taking the Tibetan plateau for example, the values of the [Formula: see text] can better reveal the detailed features of the Tibetan plateau’s Moho depth than these of the lower-order residual radial functionals (i.e. disturbing potential [Formula: see text], disturbing radial gravity vector [Formula: see text], and disturbing radial-radial gravity gradient tensor [Formula: see text]), especially for the Qaidam, Sichuan, Tarim, and Turpan basins. Numerical results over the Himalayan region demonstrate that the GC component [Formula: see text] has some potential in geophysical inversion. These residual GC functionals would help to get a better knowledge of the internal structures of the Earth and other planetary objects.

Abstract Objective This study was designed to investigate the efficacy and prognostic factors for immune checkpoint inhibitors (ICIs) combined with or without radio(chemo)therapy and to evaluate their toxicity in patients with locally advanced or recurrent/metastatic esophageal squamous cell carcinoma (LA/RM ESCC). Methods In this study, 198 patients with locally advanced or recurrent/metastatic (LA/RM) ESCC who received ICIs combined with or without radiotherapy/chemotherapy in the Department of Radiotherapy of the Fourth Hospital of Hebei Medical University were retrospectively analyzed. Univariate and multivariate analyses were performed to determine the prognostic factors for overall survival (OS) and progression free survival (PFS). The factors affecting treatment response and the occurrences of treatment-related adverse events (trAEs) were analyzed. Results The median OS and PFS were 30.4 months (95% confidence interval [CI] 15.1–45.7 months) and 15.3 months (95% CI 12.8–17.8 months), respectively. Univariate and multivariate analysis showed that the number of ICI cycles, the intervention of radiotherapy and dysphagia were independent factors affecting OS (Hazard ratio [HR] = 0.39, 2.043 and 0.365, respectively; P = 0.018, 0.001 and 0.032, respectively). The intervention of radiotherapy was an independent factor for PFS (hazard ratio [HR] = 18.149, P = 0.013). The median OS and PFS for patients who had complete response and partial response (Objective response, ORR) were 50.8 months (95% CI 25.8–75.7 months) and 20.5 months (95% CI 14.1–27.0), respectively, which were significantly higher than those in the non-ORR group (OSnon-ORR:17.5 months, 95% CI 14.0–21.0; χ2 = 13.881, P

Orthometric height datum systems are critical in the geodetic community. Nonetheless, individual nations or local regions maintain their distinct height systems. These systems, primarily determined by conventional spirit leveling, exhibit inhomogeneity, as the mean sea level does not represent an equi-geopotential surface. As such, accurately unifying global height systems is a persistent challenge. The gravity frequency shift equation provides a promising approach to this issue, offering a means to unify global height systems by comparing the frequencies of two distant clocks via optical fibers. In this study, we develop a model based on the Optical Fiber Frequency Transfer (OFFT) method, recognized for its unparalleled precision. We simulated a network of optical clocks interconnected by optical fibers to unify the height system across Southeast Asia. Our study suggests that the optical fiber clock network can realize height propagation between any two height datums at the centimeter level, providing a favorable opportunity for achieving regional height system unification.

ObjectiveTo investigate the predictive value of Controlling Nutritional Status (CONUT) score and systemic inflammation (SIS) score in the prognosis, short-term efficacy, and immune-related side effects of patient with recurrent or metastatic esophageal squamous cell carcinoma (R/M ESCC) receiving immunotherapy as second line therapy combined with or without radiotherapy.MethodsForty-eight patients with R/M ESCC who received second-line therapy with Camrelizumab were retrospectively studied. They were divided into the high and low score groups according to the CONUT and SIS score. Univariate and multivariate analyses were used to analyze factors that might affect patient prognosis and the effects of different CONUT score and SIS on the short-term efficacy and immune-related toxic and side effects of patients.ResultsThe 1- and 2-year overall survival (OS) and progression-free survival (PFS) rates were 42.9% and 22.5%, and 29.0% and 5.8%, respectively. The CONUT score ranged from 0 to 6 (3.31 ± 1.43), whereas the SIS score ranged from 0 to 2 (1.19 ± 0.73). Multivariate analysis showed that treatment related toxicity, number of cycles of Camrelizumab used, short-term effect and SIS score were independent prognostic factors for OS (P=0.044, 0.021, 0.021, 0.030, respectively), whereas SIS and CONUT scores were independent prognostic factors for PFS (P=0.005, 0.047, respectively). Patients with low CONUT/SIS score had a low incidence rate of immune-related adverse reactions (X2 = 9.735, 5.693; P=0.002, 0.017) and better short-term efficacy (X2 = 4.427, 7.438; P=0.035, 0.006).ConclusionR/M ESCC patients with low CONUT/SIS score have better prognosis, higher objective response rate, lower incidence of immune-related toxic and side effects after receiving immunotherapy as second-line therapy. CONUT scores and SIS scores may be reliable prognostic indicators for patient receiving immunotherapy as second-line therapy for R/M ESCC.

With the widespread application of low-dose computed tomography (LDCT) technology, pulmonary nodules have aroused more attention. Significant alteration in plasma metabolite levels, mainly amino acid and lipid, have been observed in patients of PNs. However, evidence on the association between central carbon metabolism and PNs are largely unknown. The aim of this study was to investigate the underlying association of PNs and plasma central carbon metabolites. We measured the levels of 16 plasma central carbon metabolites in 1954 participants who gained LDCT screening in MALSC cohort. The inverse probability weighting (IPW) technique was used to control for bias due to self-selection for LDCT in the assessed high-risk population. The least absolute shrinkage and selection operator (LASSO) penalized regression was used to deal with the problem of multicollinearity among metabolites and the combined association of central carbon metabolites with PNs was estimated by using quantile g-computation (QgC) models. A quartile increase in 3-hydroxybutyric acid, gluconic acid, succinic acid and hippuric acid was positively associated with the PNs risk, whereas a quartile increase in 2-oxadipic acid and fumaric acid was negatively associated with the risk of PNs in multiple-metabolite models. A positive but insignificant joint associations of the mixture of 16 metabolites with PNs was observed by using QgC models analyses. Further studies are warranted to clarify the association between circulating metabolites and PNs and the biological mechanisms.

ObjectiveTo evaluate the predictive role of nodal skip metastasis (NSM) in the prognosis of lymph node-positive mid-thoracic esophageal squamous cell carcinoma, and to evaluate the significance of postoperative adjuvant treatment in patients with different sites of metastatic nodes.MethodsA retrospective analysis was performed on clinical data of 321 lymph node-positive mid-thoracic esophageal squamous cell carcinoma patients who underwent surgery in the Fourth Hospital of Hebei Medical University. Based on the site and condition of lymph node metastasis by postoperative pathology, the patients were divided into two groups: NSM group and non-NSM (NNSM) group. The propensity score matching (PSM) method was employed to match the two groups. The prognostic factors of patients before and after PSM as well as the effect of different adjuvant treatment modes on the prognosis of patients before and after PSM were analyzed. SPSS 29.0 statistical software was used for analysis.ResultsPSM in a 1 : 1 matching ratio was performed, 103 patients were assigned to NSM group and NNSM group respectively. Significant differences were found in the 3- and 5-year OS and DFS between the two groups before PSM, the 3- and 5-year OS also showed a significant difference after PSM (P 0.05).ConclusionPostoperative NSM is a good prognostic factor for patients with mid-thoracic esophageal squamous cell carcinoma, postoperative adjuvant chemoradiotherapy was recommended for those group, thereby gaining survival benefits.

PurposeTo investigate the influencing factors of abdominal lymph node metastasis in thoracic esophageal squamous cell carcinoma (TESCC), and to construct its predictive model, in order to analyze the targets for postoperative radiotherapy.Methods and materialsFrom January 2008 to December 2014, the clinicopathological data of 479 patients who underwent radical resection for esophageal cancer in the Fourth Hospital of Hebei Medical University were collected and retrospectively analyzed. The influencing factors of postoperative abdominal lymph node metastasis were analyzed, and a predictive model was constructed based on their independent influencing factors. Receiver operating characteristic (ROC) curve was utilized to analyze the predictive value of this model; in the meantime, the postoperative locoregional recurrence (LRR) of this group was analyzed.ResultsThe postoperative pathology of all patients showed that the lymph node metastasis rate (LNR) was 39.7%, of which the abdominal lymph node metastasis rate was 22.0%. Logistic regression analysis revealed that the patient's lesion location, pN stage, vascular invasion, LND and mediastinal lymph node metastasis were independent risk factors for the positive rate of abdominal lymph nodes after surgery (P = 0.000, 0.000, 0.033, 0.000, 0.000). The probability of abdominal lymph node metastasis was Y = ex/(1 + ex), and X = −5.502 + 1.569 × lesion location + 4.269 × pN stage + 1.890 × vascular invasion + 1.950 × LND-4.248 × mediastinal lymph node metastasis. The area under the ROC curve (AUC) of this model in predicting abdominal lymph node metastasis was 0.962 (95% CI, 0.946–0.977). This mathematical model had a high predictive value for the occurrence of abdominal lymph node metastasis (P = 0.000), and the sensitivity and specificity of prediction were 94.6% and 88.3% respectively. The overall survival rate was significantly higher (X2 = 29.178, P = 0.000), while abdominal lymph node recurrence rate was lower in patients with negative abdominal lymph nodes than in those with negative lymph nodes (1.4%&7.7%, X2 = 12.254, P = 0.000).ConclusionThe lesion location, pN stage, vascular invasion, LND and mediastinal lymph node metastasis are independent influencing factors of abdominal lymph node metastasis in patients with TESCC. The mathematical model constructed by these indicators can accurately predict abdominal lymph node metastasis, which can help clinicians to choose the targets for postoperative radiotherapy.

Abstract Over the decades, testing gravitational red-shift (GRS) based on microwave links has made great process, including the GPA experiment, the planned Atomic Clock Ensemble in Space mission, and the China Space Station (CSS). Until now, the formulations of microwave links are almost all based on the time comparison. However, there are advantages of using frequency comparison instead of time comparison to test GRS. Here we develop a tri-frequency combination method based on the measurements of the frequency shifts of three independent microwave links between a space station and a ground station. Aiming at the frequency links’ accuracy of $$3\times 10^{-16}$$ 3 × 10 - 16 , we should consider various effects, including the Doppler effect, second-order Doppler effect, atmospheric frequency shift, tidal effects, refraction caused by the atmosphere, and Shapiro effect, with accuracy levels of tens of centimeters. The CSS will complete construction in 2022, and the formulation proposed in this study will enable us to test GRS at an accuracy level of at least $$2\times 10^{-6}$$ 2 × 10 - 6 , which is one order higher than the present accuracy level of $$7\times 10^{-5}$$ 7 × 10 - 5 .

The structure of delafloxacin meglumine was analyzed by infrared absorption (IR), ultraviolet absorption (UV), nuclear magnetic resonance (1H NMR, 13C NMR, DEPT, 1H-1H COSY, 1H-13C HSQC and 1H-13C HMBC) spectroscopy, mass spectrometry and elemental analysis. The characteristic absorption peaks in the IR spectra were discussed. The 1H and 13C NMR signals of delafloxacin meglumine were assigned, and the two-dimensional signals were used to elucidate its structure. The crystal structure of delafloxacin meglumine was studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD).

Background: Parathyroid hormone related protein (PTHrP) triggers white adipose tissue (WAT) browning and cachexia in lung cancer mouse models. It remains unknown whether excessive PTH secretion affects WAT browning and to what extent it contributes to body weight change in primary hyperparathyroidism (PHPT). Methods: Using the adeno-associated virus injection, Pth gene over-expressed mice mimicking PHPT were firstly established to observe their WAT browning and body weight alteration. The association between PTH and body weight was investigated in 496 PHPT patients. The adipose browning activities of 20 PHPT and 60 control subjects were measured with PET/CT scanning. Findings: Elevated plasma PTH triggered adipose tissue browning, leading to increased energy expenditure, reduced fat content, and finally decreased body weight in PHPT mice. Higher circulating PTH levels were associated with lower body weight (β = −0.048, P = .0003) independent of renal function, serum calcium, phosphorus,and albumin levels in PHPT patients. PHPT patients exhibited both higher prevalence of detectable brown/beige adipose tissue (20% vs 3.3%, P = .03) and increased browning activities (SUV in cervical adipose was 0.77 vs 0.49,P = .02) compared with control subjects. Interpretation: Elevated serum PTH drove WAT browning program, which contributed in part to body weight loss in both PHPT mice and patients. These results give insights into the novel pathological effect of PTH and are of importance in understanding the metabolic changes of PHPT. Fund: This research is supported by the National Key Research and Development Program of China and National Natural Science Foundation of China. Keywords: Primary hyperparathyroidism, Parathyroid hormone, Adipose tissue browning, Body weight

The Tibetan Plateau is known as the Third Pole of the Earth, playing unique roles in plate tectonics, glaciology, limnology, hydrology, climate, and environmental changes. Like major scientific hotspots elsewhere in the world, long-term geophysical data are needed for in-depth scientific studies. The Tibetan Plateau has very sparse and inadequate in situ data sets publicly available. However, large amount of satellite data have become available during the last few decades. Such data allow researchers to detect long-term evolutions of geophysical signals and to enable more accurate modeling of their mechanisms. These data, in combination with the limited available seismic/magnetic profiles and other in situ data, are poised to potentially be able to extract previously missing features vital to the interpretation of a targeted geophysical process.

According to Einstein’s general relativity theory, a precise (atomic) clock runs faster at a position with higher gravitational potential than a clock at a position with lower potential. Here, we provide a direct clock comparison using a fixed hydrogen clock and a portable hydrogen clock for geopotential determination based on the two-way satellite time and frequency transfer (TWSTFT) technique. After synchronizing the two hydrogen clocks at positions at the same height, the clocks were compared for a height difference of 22 m over a period of 14 days using the TWSTFT technique. Interpretation of the observed time elapse implies a height difference of 175 m +/- 59 m, which matches the frequency stability of our instruments. This study and relevant experiments provide a way of determining the geopotential using ultra-high precise clocks based on the TWSTFT technique in the near future.

Lake level change in the Tibetan Plateau is an important indicator for regional and global climate changes. We use altimeter data from Cryosat-2, SARAL, ICESat, and Jason-2 to detect lake level changes at different spatial and temporal resolutions over 2003 - 2017 (Jason-3 data in 2017 for validation). Cryosat-2’s SARIn mode provides precise water level time series over 59 lakes. SARAL’s waveforms are retracked to generate near monthly, high-quality measurements at 31 lakes. Jason-2 provides a reference for removing inter-altimeter biases, enabling coherent records over lakes with Jason-2 passes. After a decade of rise since the ICESat record of 2003, the lake levels of Nam Co, Selin Co, Ngangzi Co, and Chibuzhang Co became flat in 2014 - 2016 and started to fluctuate or decline after 2016. Such positive-flat-negative trends are consistent with the trend variations of mass change from Gravity Recovery and Climate Experiment (GRACE). SARAL detected persistent lake level declines over 2013 - 2016 in southern Tibet that may signify the onset of decadal reduced flows of the Yarlung Tsangpo and Brahmaputra River that could affect the water supply for their downstream regions in India and Bangladesh. Cryosat-2 and Jason-2 detected sudden lake level rises and falls around Zhuonai, Kusai, and Salt Lake associated with a 2011 lake outburst, which is confirmed by lake volume changes from two Landsat-7 images. With a careful processing and calibration, multiple altimeters allow for determining and cross-validating long-term and episodic lake level changes unachievable by a single altimeter.

The present Global Navigation Satellite System (GNSS) can provide at least double-frequency observations, and especially the Galileo Navigation Satellite System (Galileo) can provide five-frequency observations for all constellation satellites. In this contribution, precision point positioning (PPP) models with Galileo E1, E5a, E5b, E5 and E6 frequency observations are established, including a dual-frequency (DF) ionospheric-free (IF) combination model, triple-frequency (TF) IF combination model, quad-frequency (QF) IF combination model, four five-frequency (FF) IF com-bination models and an FF uncombined (UC) model. The observation data of five stations for seven days are selected from the multi-GNSS experiment (MGEX) network, forming four time-frequency links ranging from 454.6 km to 5991.2 km. The positioning and time-frequency transfer performances of Galileo multi-frequency PPP are compared and evaluated using GBM (which denotes precise satellite orbit and clock bias products provided by Geo Forschung Zentrum (GFZ)), WUM (which denotes precise satellite orbit and clock bias products provided by Wuhan University (WHU)) and GRG (which denotes precise satellite orbit and clock bias products provided by the Centre National d’Etudes Spatiales (CNES)) precise products. The results show that the performances of the DF, TF, QF and FF PPP models are basically the same, the frequency stabilities of most links can reach sub10−16 level at 120,000 s, and the average three-dimensional (3D) root mean square (RMS) of position and average frequency stability (120,000 s) can reach 1.82 cm and 1.18 × 10−15, respectively. The differences of 3D RMS among all models are within 0.17 cm, and the differences in frequency stabilities (in 120,000 s) among all models are within 0.08 × 10−15. Using the GRG precise product, the solution performance is slightly better than that of the GBM or WUM precise product, the average 3D RMS values obtained using the WUM and GRG precise products are 1.85 cm and 1.77 cm, respectively, and the average frequency stabilities at 120,000 s can reach 1.13 × 10−15 and 1.06 × 10−15, respectively.

Abstract Background Five-year overall survival rate of TESCC after surgery is low (approximately 30% to 60%), so it is meaningful to discuss the significance of PORT. Methods We retrospectively collected the data of 227 patients with PT3N0M0 esophageal cancer (EC). The failure pattern after surgery was analyzed. Difference of adjuvant PORT in patients with PT3N0M0 TESCC and the appropriate population were explored based on the relevant studies. Results There were 58 cases with intrathoracic locoregional recurrence (LRR) after radical surgery and 27 cases with distant metastasis, including 10 cases of recurrence. The recurrence rate of mediastinal lymph nodes in the thoracic cavity was 50.0%. Univariate analysis revealed that compared with patients with middle and lower thoracic EC, the 3/5-year survival rate of patients with upper thoracic EC was significantly lower, accompanied with remarkably higher thoracic LRR. Compared with those with moderately- and well-differentiated TESCC, the 3/5-year survival rate of patients with poorly differentiated TESCC was significantly lower, whereas the distant metastasis rate was notably higher. Multivariate analysis revealed that different lesion locations and different pathologic differentiation were the independent prognostic factors. The lesion location and degree of differentiation were the independent influencing factors for thoracic LRR and distant metastasis, respectively. Conclusion The intrathoracic LRR is the major failure pattern for patients with PT3N0M0 TESCC after conventional two-field lymphadenectomy. In addition, recurrence rate of PT3N0M0 TESCC was significantly higher in upper thoracic EC than in middle and lower thoracic EC. PORT is recommended to patients with PT3N0M0 upper TESCC.

In previous studies, the northern hemisphere of the Earth is considered to be in compression while the southern one is in expansion. In this study, based on three different methods, we calculate average vertical variations of the two hemispheres from velocity field data under the ITRF2008 (International Terrestrial Reference Frame 2008) solution. Results show that the northern hemisphere is in expansion at the rate about 1 mm/yr, while the compression rate of the southern hemisphere is one order smaller than the expansion rate of the northern one. After the post glacial rebound effect is subtracted, results show that the expansion and compression rates of the northern and southern hemispheres are 0.46 mm/yr and –0.19 mm/yr, respectively. Transformation between the velocity fields under ITRF2008 and ITRF2000 can explain why different authors have different conclusions about the expan­sion/compression pattern of one hemisphere or the other. Anyway, the entire Earth is expanding at a rate about 0.2 mm/yr, and this estimation coincides with results of our previous studies. The mean variation rates of the radii at different latitudes have been calculated.

Based upon SG (superconducting gravimeter) records, the autoregressive method proposed by Chao and Gilbert [1980] is used to determine the frequencies of the singlets of seven spheroidal modes (0S2, 2S1, 0S3, 0S4, 1S2, 0S0, and 3S1) and the degenerate frequencies of three toroidal modes (0T2, 0T3, and 0T4) below 1 mHz after two recent huge earthquakes, the 2010 Mw8.8 Maule earthquake and the 2011 Mw9.1 Tohoku earthquake. The corresponding quality factor Qs are also determined for those modes, of which the Qs of the five singlets of 1S2 and the five singlets (m=0, m=±2, and m=±3) of 0S4 are estimated for the first time using the SG observations. The singlet m=0 of 3S1 is clearly observed from the power spectra of the SG time series without using other special spectral analysis methods or special time series from pole station records. In addition, the splitting width ratio R of 3S1 is 0.99, and consequently we conclude that 3S1 is normally split. The frequencies and Qs of the modes below 1mHz may contribute to refining the 3D density and attenuation models of the Earth.

According to Stokes’ approach, given the gravity anomaly on the geoid as the boundary, a disturbing potential function satisfying some boundary conditions should be solved. The basic requirement is that the disturbing potential function should be harmonic in the region outside the geoid. However, since the normal gravity potential is not defined inside the reference ellipsoid (taking the WGS84 ellipsoid as an example), when the geoid is below the ellipsoidal surface, the disturbing potential function is not harmonic in the whole region outside the geoid, and is not defined on the whole geoid itself. These are theoretical difficulties in Stokes’ approach. To remove these difficulties from Stokes’ approach, this study provides a new formulation of Stokes’ approach. An inner ellipsoid with four fundamental parameters is chosen, two of which, the geocentric gravitational constant and the rotational angular velocity, coincide with the corresponding parameters of the WGS84 ellipsoid. The other two parameters, the semi-major axis and flattening, are different from the corresponding ones of the ellipsoid. Then, the normal gravity potential generated by the inner ellipsoid is determined, by requiring that it holds a constant on the surface of the inner ellipsoid or on the surface of the ellipsoid. With this new formulation, the disturbing potential function is harmonic in the whole region outside the geoid, and the difficulties in Stokes’ approach disappear. The new formulation proposed in this study is also adequate for analogous geodetic boundary-value problems.

Due to their very low noise levels in the low frequency band (3S1 that was excited by the December 26, 2004, Sumatra-Andaman earthquake (Mw = 9.3). Some SG records and the Hilbert-Huang transformation are used as an alternative data preprocessing technique, instead of the traditional detiding method. After removal of atmospheric pressure effects from the original SG records, we applied the Hilbert-Huang transformation to the SG residues, to select the signals that included the frequency band of interest, and to construct a new data series. Then, by applying the multi-station experimental technique to five 273-h-long common new data series recorded at different SG stations, we clearly observed all of the three singlets of the mode 3S1, with the central singlet more evident compared to previous studies. Observations of the low-frequency modes 3S1 (n = 0, 1, 2, ...; l = = 1,2, ...) provide constraints on the inner and outer core structure. This case study provides an alternative data-preprocessing approach to observe the splitting frequencies of the low-frequency mode type 3S1 (n = 0, 1, 2, ...).

The title compound, [Fe(C5H5)(C15H14NO2)], is a monoclinic polymorph of the previously reported triclinic form [Shi et al. (2006). Acta Cryst. C62, m407–m410]. The polymorphs feature the same strong intramolecular N—H...O=C hydrogen bonds, but show different packing modes. The molecules in the monoclinic form associate into double chains via O—H...O=C and (Cp)C—H...O—H interactions.

The title compound, [Fe4(C6H6NS)(CH3S)S(CO)11], comprises two butterfly-shaped sub-cluster cores, Fe2S2N and Fe2S2, joined together by a spiro-type μ4-S atom. The (pyridin-2-yl)methanethiolate ligand is attached to the Fe2(CO)5 unit in a μ-κN:κ2S mode, and the methanethiolate ligand is coordinated to the Fe2(CO)6 unit in a μ-κ2S fashion.