Recalibrating polyparameter linear free energy relationships and reanalyzing mechanisms for partition of nonionic organic compounds to low-density polyethylene passive sampler.

Equilibrium passive sampling techniques based on the low-density polyethylene (LDPE) film are increasingly used for determining the concentration of contaminants in water and air. Reliable models capable of predicting LDPE-water and LDPE-air partition coefficients (KiLDPEw and KiLDPEa) would be very useful. In previous studies, polyparameter linear free energy relationships (PP-LFERs) based on Abraham's solute descriptors were calibrated for LDPE-water and LDPE-air systems. Unfortunately, a portion of unreliable partition coefficients and solute descriptors were included in the calibration sets of these previous studies, leading to unexpected system parameters and predictive performance in the regression results. In this study, more reliable PP-LFERs were recalibrated for LDPE-water and LDPE-air systems (20‒25 °C) using carefully collected reliable partition coefficients and solute descriptors of various polar and nonpolar compounds (over one hundred and with low redundancy) from the literature, as well as the robust regression method. The PP-LFERs performed well with root-mean-square errors of 0.15-0.25 log units and successfully predicted KiLDPEw and KiLDPEa values spanning over 10 orders of magnitude for compounds with reliable descriptors. The partitioning mechanisms of compounds to LDPE were also reanalyzed and compared in detail with n-alkanes (C6-C16). Generally, LDPE is more prone to form dispersion interactions with solutes than n-alkanes, while it is more difficult to form cavities in LDPE. In addition, the crystallinity of LDPE is not the sole reason for the distinct constant terms presenting in PP-LFERs for LDPE-water and n-hexadecane-water systems.

Cavity nucleation in single-component homogeneous amorphous solids under negative pressure.

Understanding the cavity formation and cavity growth mechanisms in solids has fundamental and applied importance for the correct determination of their exploitation capabilities and mechanical characteristics. In this work, we present the molecular dynamics simulation results for the process of homogeneous formation of nanosized cavities in a single-component amorphous metallic alloy. To identify cavities of various shapes and sizes, an original method has been developed, which is based on filling cavities by virtual particles (balls) of the same diameter. By means of the mean first-passage time analysis, it was shown that the cavity formation in an amorphous metallic melt is the activation-type process. This process can be described in terms of the classical nucleation theory, which is usually applied to the case of first order phase transitions. Activation energy, critical size and nucleation rate of cavities are calculated, the values of which are comparable with those for the case of crystal nucleation in amorphous systems.

Osteoclasts and Macrophages-Their Role in Bone Marrow Cavity Formation During Mouse Embryonic Development.

The formation of the bone marrow cavity is a prerequisite for endochondral ossification. In reviews and textbooks, it is occasionally reported that osteoclasts are essential for bone marrow cavity formation removing hypertrophic chondrocytes. Mice lacking osteoclasts or having functionally defective osteoclasts have osteopetrotic bones, yet they still form a bone marrow cavity. Here, we investigated the role of osteoclasts and macrophages in bone marrow cavity formation during embryogenesis. Macrophages can assist osteoclasts in matrix removal by phagocytosing resorption byproducts. Rank-deficient mice, lacking osteoclasts, and Pu.1-deficient mice, lacking monocytes, macrophages, and osteoclasts, displayed a delay in bone marrow cavity formation and a lengthening of the zone of hypertrophic chondrocytes. F4/80-positive monocyte/macrophage numbers increased by about fourfold in the bone marrow cavity of E18.5 Rank-deficient mice. Based on lineage-tracing experiments, the majority of the excess F4/80 cells were derived from definitive hematopoietic precursors of the fetal liver. In long bones of both Rank-/- and Pu.1-/- specimens, Mmp9-positive cells were still present. In addition to monocytes, macrophages, and osteoclasts, Ctsb-positive septoclasts were lost in Pu.1-/- specimens. The mineralization pattern was altered in Rank-/- and Pu.1-/- specimens, revealing a significant rise in transverse-oriented mineralized structures. Taken together, our findings imply that early on during bone marrow cavity formation, osteoclasts facilitate the entry of blood vessels and later the turnover of hypertrophic chondrocytes, whereas macrophages appear to play no major role. Furthermore, the absence of septoclasts in Pu.1-/- specimens suggests that septoclasts are either derived from Pu.1-dependent precursors or require PU.1 activity for their differentiation. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

The Effect of the Spargers Design on the Wastewater Treatment of Gas-Liquid Dispersion Process in a Stirred Tank.

The hydrodynamic and power characteristics of curved Rushton impeller in an air-wastewater system were investigated using the CFD-PBM method. Studies were conducted primarily in a mixing vessel of diameter 0.39 m. The inference of operating conditions, sparger distribution, and numbers on bulk flow patterns, gas-filled cavity formation, and power consumption have been investigated in detail. It found that the gassed power consumption is closely related to cavity shape and flow patterns. In particular, the development of large cavities causes a significant reduction in power drawn, impeller pumping capacity, and gas dispersion capability. The sparger distribution and location have a strong influence on relative power drawn, power required to disperse gas, and stability of operation. Of the sparger configurations studied, the use of three sparger distributions is suggested, since relative power drawn, gas dispersion capability, and flow patterns in dispersing gas are all enhanced.

Sustaining Robust Cavities with Slippery Liquid-Liquid Interfaces.

The formation of a stable gas cavity on the surfaces of solid bodies is essential for many practical applications, such as drag reduction and energy savings, owing to the transformation of the originally sticky solid-liquid interface into a free-slip liquid-vapor interface by the creation of either liquid repellency or a Leidenfrost state on the surfaces. Here, it is shown that the simple infusion of a textured sphere with a smooth, slippery liquid layer can more easily create and sustain a stable gas cavity in a liquid at lower impact velocities compared to a dry solid sphere with the same contact angle. With a key parameter of curvature ratio, the early lamella dynamics during water entry of spheres and drops impact on planes are first unified. With the perspective of wetting transition, the unforeseen phenomenon of prone to cavity formation are successfully explained, which is the preferential lamella detachment from a slippery surface due to the higher viscosity of the lubricant relative to air. It is envisioned that the findings will provide an important and fundamental contribution to the quest for energy-efficient transport.

Cavity formation and its predictors in noncavitary nodular bronchiectatic Mycobacterium avium complex pulmonary disease.

INTRODUCTION: The temporal dynamics of cavity formation in patients with the noncavitary nodular bronchiectatic (NC-NB) form of Mycobacterium avium complex pulmonary disease (MAC-PD) have not yet been well described. We aimed to investigate the development of new cavities in the NC-NB form of MAC-PD. METHODS: Of the patients diagnosed with NC-NB-type MAC-PD between 2002 and 2013 and followed-up until July 2018 at a tertiary referral center in South Korea, we identified 589 patients who underwent follow-up chest computed tomography at least once after the diagnosis and retrospectively analysed their medical records. RESULTS: The patients' mean age was 62.0 years, 64.7% were women. During the median follow-up of 3.8 years (interquartile range [IQR] 1.7-5.9), new cavity formation was noted in 51 (8.7%) patients. The median interval between the diagnosis of NC-NB MAC-PD and cavity formation was 3.7 years (IQR 1.8-5.4), with a constant occurrence over time. The Cox regression analysis showed that a history of pulmonary tuberculosis (adjusted hazard ratio [HR] 1.85; 95% confidence interval [CI] 1.06-3.23; P = 0.030) and M. intracellulare as the causative organism (adjusted HR 2.03; 95% CI 1.15-3.59; P = 0.014) were independently associated with new cavity formation. CONCLUSIONS: New cavity formation was noted in 8.7% of the patients with NC-NB MAC-PD in approximately 4 years after diagnosis, particular in those infected with M. intracellulare and those with a previous history of tuberculosis.

Solitary fibrous tumour of the pleura arising in a pulmonary cavity.

Solitary fibrous tumour of the pleura (SFTP) arising in a cavity is extremely rare. A 66-year-old Japanese male presented with an abnormal shadow on his chest X-ray. Chest computed tomography showed a cavity of approximately 18 mm in diameter between the upper and lower lobes that contained a solid nodule within. Under the thoracoscope, the peduncle cystic tumour was removed with sufficient surgical margin. Macroscopically, a tumour of about 15 mm in diameter arose in the cystic cavity. Immunohistochemical stains were positive for CD34, bcl-2, and signal transduction and activator of transcription 6 (STAT6) but negative for smooth muscle actin (SMA), desmin, and epithelial membrane antigen (EMA), and a diagnosis of SFTP was made. The patient remains well without recurrence or any complications at two and a half years after the operation. SFTP should be considered when a tumour arises in a cavity existing in an interlobar space. It is important to determine whether the tumour is pedunculated or sessile during surgery and to perform the appropriate surgical procedure.

Rapidly Progressive Multiple Cavity Formation in Necrotizing Pneumonia Caused by Community-acquired Methicillin-resistant Staphylococcus aureus Positive for the Panton-Valentine Leucocidin Gene.

A 66-year-old man was transferred to our hospital for pneumonia that was resistant to sulbactam/ampicillin and levofloxacin therapy. Chest computed tomography showed the rapidly progressive formation of multiple cavities. Methicillin-resistant Staphylococcus aureus (MRSA) was isolated, and the patient was diagnosed with necrotizing pneumonia caused by community-acquired MRSA (CA-MRSA). The MRSA strain had type IV staphylococcus cassette chromosome mec and genes encoding Panton-Valentine leucocidin (PVL). CA-MRSA necrotizing pneumonia with the PVL gene is rare; only three cases have been previously reported in Japan. We administered anti-MRSA antibiotics and the patient achieved complete clinical and radiological improvement.

Short and Solid Culm/RFL/APO2 for culm development in rice.

The culm development of rice is characterized by elongation and medullary cavity (MC) formation, which are determined by node formation meristem and residual meristem, respectively. Although many factors have been shown to affect culm elongation, molecules involved in MC formation remained to be identified. In this study, we show that a point mutation in SHORT and SOLID CULM (SSC), the rice homologue of Arabidopsis LFY, resulted in plants with drastically reduced culm length and completely abolished MC formation. Analysis of transgenic plants with moderately enhanced SSC expression revealed significant decreases in plant height and MC size in contrast to slight changes in heading date, indicating that the culm developmental process is much more tightly monitored by the gene. Transcriptomic analysis revealed the differential expression of knotted-1 like homeobox (KNOX) protein genes and gibberellin (GA) metabolic genes in the ssc mutant background, and most of the genes contained well-conserved LFY-binding cis-elements that could be effectively recognized by SSC. Genetic analysis found that the reduced culm length of the mutant could be largely rescued by the GA-accumulating mutation eui, whereas MC formation remained unchanged in the double mutant plants. Taken together, our results suggest that SSC affects culm elongation mainly through maintaining GA homeostasis, while functions in MC formation by mediating residual meristem activity possibly via the KNOX pathway. The present study provides a potential strategy for improving the culm morphology and plant architecture in rice by manipulating SSC and/or its downstream components.

JOURNAL CLUB: Longitudinal Qualitative Characterization of MRI Features After Laser Interstitial Thermal Therapy in Drug-Resistant Epilepsy.

OBJECTIVE: Laser interstitial thermal therapy (LITT), a method for ablating brain tissue under real-time MR thermometry, has been used more frequently in recent years to treat nonmalignant lesions. The purpose of this study is to longitudinally characterize MRI features after LITT in patients with drug-resistant epilepsy, primarily in the setting of mesial temporal sclerosis. MATERIALS AND METHODS: MR images from 23 consecutive patients who underwent LITT were retrospectively reviewed. All patients had images obtained immediately after the ablation. Multiple patients had follow-up imaging at various time points after treatment, from postoperative days 7 through 1539. A total of 54 MRI studies were reviewed. RESULTS: Immediately after LITT, MR images showed a ring-enhancing lesion at the ablation site with minimal surrounding edema. Seven images showed increased enhancement of the ipsilateral choroid plexus. Images in the subacute phase showed a mild increase in edema with similar enhancement. Images in the transitional phase showed a decrease in edema with variable enhancement. Images in the chronic phase showed minimal gliosis with or without cavity formation or cavity formation alone, with either decreased or no enhancement. CONCLUSION: This report describes the time course of the imaging findings after LITT for drug-resistant epilepsy. The typical stages include rim-enhancing lesion with minimal edema, followed by an increase in edema, to eventual gliosis and nonenhancing cavity formation. Radiologists need to be familiar with the postablation findings to minimize misdiagnosis and prevent unnecessary workup.

Early tumor cavitation with regorafenib in metastatic colorectal cancer: A case report.

Tumoral cavity formation is a characteristic phenomenon reported in anti-angiogenic therapy in lung lesions. A 57-year-old male with multiple pulmonary metastases from colorectal cancer treated with an oral tyrosine kinase inhibitor, regorafenib, exhibited a characteristic cavity formation after the first two cycles. The decrease in the size of tumors was calculated as 38%, and there were associated decreases in the serum concentrations of the tumor markers carcinoembryonic antigen and CA19-9. After eight cycles of treatment, the cavity gradually disappeared through filling-in. This unique morphological response is not only reported in lung cancer but also in liver metastasis in colorectal cancer. However, the association between morphological changes including cavity formation and clinical benefit remains controversial. Pulmonary hemorrhage and pneumothorax are well-known consequences of cavitation, as reported with the other anti-angiogenic inhibitors. Early tumor cavitation in lung metastasis may demonstrate the predictive potential of regorafenib in colorectal cancer, although it is necessary to be mindful of toxicity.

Direct in Situ TEM Observation of Modification of Oxidation by the Injected Vacancies for Ni-4Al Alloy Using a Microfabricated Nanopost.

Vacancy injection and selective oxidation of one species in bimetallic alloy at high temperature is a well-known phenomenon. However, detailed understanding of the behavior of the injected vacancies and consequently their effect on oxidation remains elusive. The current research examines the oxidation of high-purity Ni doped with 4.1 at. % Al using in situ transmission electron microscopy (TEM). Experiments are performed on nanoposts fabricated from solution-annealed bulk material that are essentially single crystal samples. Initial oxidation is observed to occur by multisite oxide nucleation, formation of an oxide shell followed by cavity nucleation and growth at the metal/oxide interface. One of the most interesting in situ TEM observations is the formation of a cavity that leads to the faceting of the metal and subsequent oxidation occurring by an atomic ledge migration mechanism on the faceted metal surface. Further, it is directly observed that metal atoms diffuse through the oxide layer to combine with oxygen at the outer surface of the oxide. The present work indicates that injection of vacancies and formation of cavity will lead to a situation where the oxidation rate is essentially controlled by the low surface energy plane of the metal, rather than by the initial terminating plane at the metal surface exposed to the oxidizing environment.

MRI Characteristics of the Evolution of Supratentorial Recent Small Subcortical Infarcts.

OBJECTIVE: Morphological changes of recent small subcortical infarcts are not well defined. The purpose of the present study was to describe the MRI characteristics of the evolution for this stroke subtype. METHODS: We conducted a retrospective review of patients diagnosed with definite supratentorial recent small subcortical infarcts according to the ASCO classification with baseline and follow-up MRI (≥90 days of stroke onset). We investigated the incidence of cavity formation, the infarct volume change, and the positional relationship between infarct lesions and preexisting white matter hyperintensities (WMHs) of presumed vascular origin. RESULTS: We identified 62 patients with a median age of 71 years (range: 30-87). Median follow-up period was 26 months (range: 3-99). Cavity formation was observed in 38 infarct lesions (61%). Eighteen lesions (29%) were partially adjacent to WMHs and 7 (11%) were fused into WMHs. In a multiple logistic regression analysis, age [odds ratio per 5-year increase: 1.34; 95% confidence interval (CI): 1.03-1.80; p = 0.03] and baseline infarct volume (odds ratio per 1-ml increase: 4.7; 95% CI: 1.6-19.7; p = 0.003) were independent predictors of cavity formation. There was a significant volume reduction between baseline and follow-up infarct lesions (median volume reduction rate: 44%). CONCLUSION: More than one-third of recent small subcortical infarcts do not lead to cavity formation and 40% of infarct lesions overlap with WMHs. Our data indicate the continuity between recent small subcortical infarcts and WMHs.

Chronic Ulceration and Sinus Formation due to Foreign Body: An Often-Forgotten Problem.

Foreign bodies like residues of suture or mesh may lead to a foreign body reaction, cavity formation and continuous secretion and perhaps ulceration. We present a more than 9 years long medical record of a 49 year old man after a simple surgical procedure. The background was a sinus formation generated from a foreign body reaction. The case report shows that this condition is often overlooked and even using advanced equipment, it is difficult to diagnose. The only solution is to diagnose and remove the triggering cause. Fistulography and ultrasound scanning seem to be the optimal diagnostic tool in these cases. The knowledge of the foreign body reaction in tissue continuously needs to be reestablished in the health care system especially in areas, where implantation of foreign material is used.

Differences in the prognostic implications of vascular invasion between lung adenocarcinoma and squamous cell carcinoma.

OBJECTIVES: Vascular invasion (VI) has been accepted as a universally important prognostic factor for patients with lung carcinoma. However, the clinical significance of VI in each of the histological subtypes has been unclear. The aim of the present study was to investigate differences in the clinicopathological implications of VI between adenocarcinoma and squamous cell carcinoma. METHOD: A total of 336 patients were evaluated, of whom 81 were diagnosed as having peripheral-type squamous cell carcinoma, and 255 as having adenocarcinoma. RESULT: Among the 336 patients, the five-year survival rates for those who were VI-positive and VI-negative were 38.4% and 76.3%, respectively, the difference being significant (p<0.0001). Multivariate analysis identified VI as an independent prognostic factor (hazard ratio: 1.86). Although the difference in cancer-free survival between VI-positive and -negative patients was statistically significant for adenocarcinoma (p<0.0001), it was not significant for squamous cell carcinoma (p=0.086). For adenocarcinoma, the difference between the survival curves for VI-positive and -negative patients was significant for the subtypes with a predominant lepidic (p<0.0001), papillary (p=0.0026), and acinar (p=0.0060) component, whereas that for the predominantly solid subtype was not significant (p=0.58). Squamous cell carcinomas were then divided into two groups on the basis of the diameter of vessels that had been invaded by the cancer cells: large-vessel invasion (LVI; 1000 µm or more) and small-vessel invasion (SVI; less than 1000 µm). Although there was no difference in the survival curves between the LVI and SVI groups, the LVI group showed a significantly higher incidence of cavity formation and distant metastasis. CONCLUSION: We conclude that VI is a useful prognostic indicator in lung carcinoma, although the clinical implications of VI differ between adenocarcinoma and squamous cell carcinoma.