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1.
Ecol Evol ; 14(6): e11475, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38932972

ABSTRACT

Cyanobacterial blooms in freshwater sources are a global concern, and gaining insight into their causes is crucial for effective resource management and control. In this study, we present a novel computational framework for the causal analysis of cyanobacterial harmful algal blooms (cyanoHABs) in Lake Kinneret. Our framework integrates Convergent Cross Mapping (CCM) and Extended CCM (ECCM) causal networks with Bayesian Network (BN) models. The constructed CCM-ECCM causal networks and BN models unveil significant interactions among factors influencing cyanoHAB formation. These interactions have been validated by domain experts and supported by evidence from peer-reviewed publications. Our findings suggest that Microcystis flos-aquae levels are influenced not only by community structure but also by ammonium, phosphate, oxygen, and temperature levels in the weeks preceding bloom occurrences. We demonstrated a non-parametric computational framework for causal analysis of a multivariate ecosystem. Our framework offers a more comprehensive understanding of the underlying mechanisms driving M. flos-aquae blooms in Lake Kinneret. It captures complex interactions and provides an explainable prediction model. By considering causal relationships, temporal dynamics, and joint probabilities of environmental factors, the proposed framework enhances our understanding of cyanoHABs in Lake Kinneret.

2.
Ultrasound Obstet Gynecol ; 63(1): 127, 2024 01.
Article in English | MEDLINE | ID: mdl-38166000
3.
Ultrasound Obstet Gynecol ; 63(1): 9-14, 2024 01.
Article in English | MEDLINE | ID: mdl-37470679

ABSTRACT

OBJECTIVE: To determine whether visual biofeedback can be used during labor as an effective tool for shortening the second stage of labor and reducing the need for instrumental delivery. METHODS: This was a single-center randomized controlled trial. Nulliparous women under epidural anesthesia were randomized at the point of full dilation into the biofeedback group (n = 50) or the control group (n = 50). Both groups received coached maternal pushing during four consecutive contractions, while an experienced obstetrician performed transperineal ultrasound. Only women in the biofeedback group observed the ultrasound display screen. Following this intervention, labor was managed routinely by the obstetric team. Angle of progression (AOP) was measured at rest and while pushing, before and during the first and fourth contractions. Second-stage duration and delivery outcomes were compared between groups. RESULTS: Visual biofeedback did not affect the duration of the second stage, which lasted for a median of 2.28 (interquartile range (IQR), 1.25-3.10) h in the biofeedback group vs 2.08 (IQR, 1.58-3.02) h in the control group (P = 0.981). AOP was significantly higher in the biofeedback group compared with the control group, both at rest before the fourth contraction (mean ± SD, 142.6° ± 15.9° vs 136.8° ± 13.1°; P = 0.049) and while pushing during the fourth contraction (mean ± SD, 159.3° ± 19.2° vs 149.4° ± 15.1°; P = 0.005). The increase in AOP was significantly higher in the biofeedback compared with the control group between rest and pushing at the last push (mean ± SD, 16.6° ± 11.0° vs 12.6° ± 8.3°; P = 0.041) and between the first rest and last push (mean ± SD, 24.4° ± 13.6° vs 17.9° ± 11.3°; P = 0.011). The rate of intact perineum was similar between groups (12% vs 8%; P = 0.505). CONCLUSIONS: Visual biofeedback during the second stage of labor may facilitate descent of fetal head during maternal pushing without affecting second-stage duration, possibly due to the short duration of the intervention. Future studies should focus on continuous intervention throughout the second stage of labor. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Delivery, Obstetric , Labor Stage, Second , Pregnancy , Female , Humans , Prospective Studies , Ultrasonography , Biofeedback, Psychology
4.
J Laryngol Otol ; 137(5): 515-519, 2023 May.
Article in English | MEDLINE | ID: mdl-35855639

ABSTRACT

BACKGROUND: A seasonal trend of patients with idiopathic sudden sensorineural hearing loss may direct research into possible aetiology. METHODS: This study reviewed data from the medical records of patients who presented from 2004 to 2019 and who were diagnosed with new-onset idiopathic sudden sensorineural hearing loss. Seasonal pattern was assessed using chi-square and Rayleigh tests, and further confirmed by Monte Carlo simulation. RESULTS: The study included 740 patients with a mean age of 48.3 years and a median age of 49 years. There was no statistical evidence for a difference in the distribution of sensorineural hearing loss cases for the four seasons of each year or with the cumulative data. New-onset idiopathic sudden sensorineural hearing loss cases averaged around 11 per month; there was no statistical evidence for a seasonal difference, as determined either by the Rayleigh test or with Monte Carlo simulation. CONCLUSION: There was no evidence to support the claim that idiopathic sudden sensorineural hearing loss incidence displays a seasonal pattern. More research is necessary to explore potential external factors such as climate or infection.


Subject(s)
Hearing Loss, Sensorineural , Hearing Loss, Sudden , Humans , Hearing Loss, Sensorineural/diagnosis , Hearing Loss, Sensorineural/epidemiology , Seasons , Retrospective Studies , Cross-Sectional Studies , Hearing Loss, Sudden/diagnosis , Hearing Loss, Sudden/epidemiology , Mediterranean Region , Incidence , Male , Female , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Weather
5.
Gynecol Oncol ; 157(2): 392-397, 2020 05.
Article in English | MEDLINE | ID: mdl-32151375

ABSTRACT

OBJECTIVE: To evaluate the treatment outcome and survival of patients with epithelial ovarian cancer recurrence isolated to the retroperitoneal lymph nodes compared to intraperitoneal spread. METHODS: A retrospective cohort study including women with recurrence of epithelial ovarian, cancer, who were treated at a single medical center, between 2000 and 2015. Patients were classified into three groups according to the site of recurrence: intraperitoneal only, retroperitoneal lymph nodes only, and both. Response to treatment was assessed by the RECIST criteria. RESULTS: Out of 135 patients in our cohort, 66 were diagnosed with intraperitoneal recurrence, 30 with retroperitoneal lymph node recurrence and 39 with combined site recurrence. The clinical, pathological and surgical characteristics were similar among all groups, besides CA-125 which was significantly lower in the retroperitoneal recurrence group at diagnosis, end of treatment and recurrence. The median follow-up period was 45.8 months. Overall survival (OS) and post relapse survival (PRS) were significantly higher in the retroperitoneal recurrence group vs. the intraperitoneal and combined site recurrence groups. (OS - 93.07, 47.9 and 41.7 months, respectively, p < .001, PRS - 68.57, 29.67 and 19.7 months, respectively, p < .001). On cox's regression analysis, retroperitoneal recurrence was found to be an independent prognostic factor for survival. CONCLUSIONS: The site of recurrence has significant prognostic value regarding PRS and OS. Patients with recurrence limited to the retroperitoneal lymph nodes have a favourable prognosis with median survival longer than 5 years.


Subject(s)
Carcinoma, Ovarian Epithelial/pathology , Carcinoma, Ovarian Epithelial/therapy , Lymph Nodes/pathology , Neoplasm Recurrence, Local/pathology , Ovarian Neoplasms/pathology , Ovarian Neoplasms/therapy , Adult , Aged , Aged, 80 and over , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carboplatin/administration & dosage , Carcinoma, Ovarian Epithelial/drug therapy , Carcinoma, Ovarian Epithelial/surgery , Chemotherapy, Adjuvant , Cohort Studies , Female , Humans , Kaplan-Meier Estimate , Lymph Nodes/surgery , Middle Aged , Neoadjuvant Therapy , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/surgery , Paclitaxel/administration & dosage , Prognosis , Progression-Free Survival , Retrospective Studies
6.
Sci Rep ; 7: 40659, 2017 01 18.
Article in English | MEDLINE | ID: mdl-28098171

ABSTRACT

A fourth century BCE silver jewellery collection, which is part of two hoards of Samarian coins (the Samaria and Nablus Hoards), was studied by non-destructive analyses. The collection, which consists of pendants, rings, beads and earrings, had been examined by visual testing, multi-focal microscopy and SEM-EDS analysis. In order to enhance our knowledge of past technologies of silver jewellery production, we developed a metallurgical methodology based on the chemical composition of the joints and bulk. The results show that all artefacts are made of silver containing a small percentage of copper. Higher copper concentrations were measured in the joining regions. Our research indicates that the manufacturing of the jewellery from both hoards involved similar techniques, including casting, cutting, hammering, bending, granulating and joining methods, indicating that the artefacts were made by trained silversmiths. Although the burial date of the Samaria Hoard - 352 BCE - is some 21 years earlier than that of the Nablus Hoard - circa 331 BCE, a noted continuity in the local production technology is apparent in the analysed items. This information provides better understanding of the technological abilities in the late Persian-period province of Samaria and bears implications on the local silver coins produced in the region.

7.
Nat Mater ; 15(4): 444-9, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26828315

ABSTRACT

Revealing the mechanisms of electronic transport through metal-molecule interfaces is of central importance for a variety of molecule-based devices. A key method for understanding these mechanisms is based on the study of conductance versus molecule length in molecular junctions. However, previous works focused on transport governed either by coherent tunnelling or hopping, both at low conductance. Here, we study the upper limit of conductance across metal-molecule-metal interfaces. Using highly conducting single-molecule junctions based on oligoacenes with increasing length, we find that the conductance saturates at an upper limit where it is independent of molecule length. With the aid of two prototype systems, in which the molecules are contacted by either Ag or Pt electrodes, we find two different possible origins for conductance saturation. The results are explained by an intuitive model, backed by ab initio calculations. Our findings shed light on the mechanisms that constrain the conductance of metal-molecule interfaces at the high-transmission limit.

8.
Phys Rev Lett ; 113(23): 236603, 2014 Dec 05.
Article in English | MEDLINE | ID: mdl-25526145

ABSTRACT

The interaction of individual electrons with vibrations has been extensively studied. However, the nature of electron-vibration interaction in the presence of many-body electron correlations such as a Kondo state has not been fully investigated. Here, we present transport measurements on a Copper-phthalocyanine molecule, suspended between two silver electrodes in a break-junction setup. Our measurements reveal both zero bias and satellite conductance peaks, which are identified as Kondo resonances with a similar Kondo temperature. The relation of the satellite peaks to electron-vibration interaction is corroborated using several independent spectroscopic indications, as well as ab initio calculations. Further analysis reveals that the contribution of vibration-induced inelastic current is significant in the presence of a Kondo resonance.

11.
Plant Biol (Stuttg) ; 13 Suppl 1: 62-70, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21134088

ABSTRACT

Temperate deciduous forest trees flower in spring, a period that starts when the trees lack leaves and when weather is unpredictable, including frost events, and ends when the forest becomes green and vertical microclimatic gradients are established. This paper asks whether there are spatio-temporal patterns in the development of flowering in trees, and how they relate to reproductive processes. Using a crane, flowering phenology was studied in the crowns of ca. 200 trees of four species, from early spring (ash) through the period of leaf-unfolding (maples) to early summer (lime). Flowering levels in different crown regions were documented quantitatively and repeatedly during the flowering season and compared among individuals and among species. Early-flowering trees displayed a clear and consistent acropetalous and centrifugal flowering pattern, while this pattern disappeared in species that flowered after leaves unfolded. This pattern was superposed on the basic flowering rhythm of each species, and was influenced by effects of direct sunlight, acting at a small scale in early spring and at a large scale in early summer. As this acropetalous centrifugal pattern contrasts the microclimatic gradients that develop only after leaves unfold, it might indicate physiological processes in the 'awakening' of trees, as well as evolutionary processes that took place in temperate trees during adaptation to a temperate climate.


Subject(s)
Acer/physiology , Flowers/growth & development , Fraxinus/physiology , Tilia/physiology , Germany , Phenotype , Reproduction , Seasons , Sunlight , Trees/growth & development , Weather
12.
Aliment Pharmacol Ther ; 30(11-12): 1128-36, 2009 Dec 01.
Article in English | MEDLINE | ID: mdl-19899197

ABSTRACT

BACKGROUND: Inflammatory bowel disease (IBD) patients undergo multiple radiological evaluations. AIM: To estimate total and abdominal radiation exposure from diagnostic X-ray investigations in IBD patients and the associated risk factors. METHODS: Patients with Crohn's disease (CD) or ulcerative colitis (UC) treated in the IBD clinic were recruited. Clinical data were extracted from patient files and radiological data were obtained from the central HMO computer data base. RESULTS: A total of 199 CD and 125 UC patients were included. The mean cumulative estimated doses (CED) for CD and UC were 21.1 19.5 and 15.1 20.4 millisieverts (mSv) respectively (P < 0.001). Twenty-three patients (7.1%) had an estimated CED of > or =50 mSv. In multivariate analyses, predictors of increased CED were: surgery (OR 5.68, 95% CI: 2.73-11.8, P < 0.001), CD (OR 2.56, 95% CI: 1.29-5.07, P = 0.007), prednisone use (OR 2.0, 95% CI: 1.11-3.67, P = 0.02), first year of disease (OR 6.4, 95% CI: 1.3-32, P = 0.02) and age in the upper quartile(OR 3.26, 95% CI: 1.68-6.3, P = 0.001). CONCLUSIONS: Diagnosis of CD, IBD-related surgery, prednisone use, first year of diagnosis and age on the upper quartile are independent predictors of increased exposure in IBD patients. Alternative investigations which do not require radiation exposure should be considered for patients at risk for increased radiation exposure.


Subject(s)
Colitis, Ulcerative/diagnostic imaging , Crohn Disease/diagnostic imaging , Diagnostic Imaging/adverse effects , Neoplasms, Radiation-Induced/etiology , Radiation Injuries/etiology , Adult , Age Factors , Analysis of Variance , Colitis, Ulcerative/complications , Crohn Disease/complications , Dose-Response Relationship, Radiation , Female , Humans , Incidence , Israel/epidemiology , Male , Neoplasms, Radiation-Induced/epidemiology , Neoplasms, Radiation-Induced/prevention & control , Radiation Injuries/epidemiology , Radiography , Risk Factors
14.
Phys Rev Lett ; 101(4): 046801, 2008 Jul 25.
Article in English | MEDLINE | ID: mdl-18764352

ABSTRACT

Highly conductive molecular junctions were formed by direct binding of benzene molecules between two Pt electrodes. Measurements of conductance, isotopic shift in inelastic spectroscopy, and shot noise compared with calculations provide indications for a stable molecular junction where the benzene molecule is preserved intact and bonded to the Pt leads via carbon atoms. The junction has a conductance comparable to that for metallic atomic junctions (around 0.1-1G0), where the conductance and the number of transmission channels are controlled by the molecule's orientation at different interelectrode distances.

15.
Phys Rev Lett ; 100(19): 196804, 2008 May 16.
Article in English | MEDLINE | ID: mdl-18518474

ABSTRACT

Point contact spectroscopy on a H(2)O molecule bridging Pt electrodes reveals a clear crossover between enhancement and reduction of the conductance due to electron-vibration interaction. As single-channel models predict such a crossover at a transmission probability of tau=0.5, we used shot noise measurements to analyze the transmission and observed at least two channels across the junction where the dominant channel has a tau=0.51 +/- 0.01 transmission probability at the crossover conductance, which is consistent with the predictions for single-channel models.

16.
Radiat Prot Dosimetry ; 130(2): 213-23, 2008.
Article in English | MEDLINE | ID: mdl-18337294

ABSTRACT

For dose assessment of workers at Nuclear Research Center Negev exposed to natural uranium, spot urine samples are analysed and the results are normalised to 24-h urine excretion based on 'standard' man urine volume of 1.6 l d(-1). In the present work, the urine volume, uranium level and creatinine concentration were determined in two or three 24-h urine collections from 133 male workers (319 samples) and 33 female workers (88 samples). Three volunteers provided urine spot samples from each voiding during a 24-h period and a good correlation was found between the relative level of creatinine and uranium in spot samples collected from the same individual. The results show that normalisation of uranium concentration to creatinine in a spot sample represents the 24-h content of uranium better than normalisation to the standard volume and may be used to reduce the uncertainty of dose assessment based on spot samples.


Subject(s)
Occupational Exposure , Radiation Monitoring , Uranium/urine , Adult , Creatinine/urine , Female , Humans , Male , Middle Aged
17.
J Phys Chem B ; 110(50): 25521-4, 2006 Dec 21.
Article in English | MEDLINE | ID: mdl-17166002

ABSTRACT

We report on high-resolution electronic measurements of doped organic thin-film transistors using Kelvin probe force microscopy. Measurements conducted on field effect transistors made of N,NI-diphenyl-N,NI-bis(1-naphthyl)-1,1I-biphenyl-4,4I-diamine p-doped with tetrafluoro-tetracyanoquinodimethane have allowed us to determine the rich structure of the doping-induced density of states. In addition, the doping process changes only slightly the Fermi energy position with respect to the highest occupied molecular orbital level center. The moderate change is explained by two counter-acting effects on the Fermi energy position: the doping-induced additional charge and the broadening of the density of states.

19.
J Thromb Haemost ; 4(5): 1078-85, 2006 May.
Article in English | MEDLINE | ID: mdl-16689762

ABSTRACT

BACKGROUND: Mutations of the 3' end mRNA-processing signal of the prothrombin (F2) gene have been reported to cause elevated F2 plasma concentrations, thrombosis, and complications of pregnancy. Whereas the common F2 20210*A mutation is almost exclusively found in Caucasians, the F2 20209*T mutation has been reported in Afro-Americans and Afro-Caribbeans only. PATIENTS AND METHODS: Using LightCycler technology, three unrelated Jewish-Moroccan patients tested for obstetric complications were found to be carriers of the F2 20209*T allele. A detailed molecular analysis was performed to identify the functional impact of this mutation. RESULTS: We report three unrelated women of Jewish-Moroccan origin with a F2 20209*T mutation and fetal loss or infertility. The functional analysis revealed that the F2 20209*T mutation stimulates 3' end processing and up-regulates prothrombin protein expression as assessed by a highly sensitive luminescence-based reporter system. CONCLUSIONS: This is the first report of 20209*T in Caucasians, and functional analysis demonstrates that F2 20209*T falls into a general category of mutations of the F2 gene, which may possibly contribute to thrombophilia and complications of pregnancy by interfering with a tightly balanced architecture of non-canonical F2 3' end formation signals.


Subject(s)
Cytosine/chemistry , Jews , Mutation , Prothrombin/genetics , Thymine/chemistry , White People , Adult , Aged , Base Sequence , DNA Primers , Female , Humans , Male , Morocco/ethnology , RNA Processing, Post-Transcriptional , RNA, Messenger/genetics , RNA, Messenger/metabolism
20.
Radiat Prot Dosimetry ; 118(1): 106-10, 2006.
Article in English | MEDLINE | ID: mdl-15985497

ABSTRACT

The (234)U/(238)U ratio in water, hair and nails samples was determined by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) and inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) and by alpha-spectrometry for the water samples only. A correlation of 0.99 was found between the two ICPMS methods and of 0.98 with alpha-spectrometry. The range of activity ratios was between 0.9 and 2.6 according to the MC-ICPMS measurements. The reproducibility of both ICPMS techniques was better than 4% for water samples containing 1 mug l(-1) of uranium and a (234)U/(238)U atom ratio of 54.9 x 10(-6). Sample preparation for the ICPMS consisted of dilution of water samples containing >10 microg l(-1) of uranium and measurement time was approximately 1 min, while alpha-spectrometry involved pre-concentration and separation of the uranium and counting times of 1,000 min.


Subject(s)
Environmental Exposure/analysis , Hair/chemistry , Nails/chemistry , Radiation Monitoring/methods , Uranium/analysis , Water Pollutants, Radioactive/analysis , Water Supply/analysis , Body Burden , Humans , Mass Spectrometry , Radiation Dosage , Reproducibility of Results , Risk Assessment/methods , Risk Factors
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