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"Shaar, R."
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Geomagnetic Field Intensity During the First Millennium BCE From Royal Judean Storage Jars: Constraining the Duration of the Levantine Iron Age Anomaly
by
Sabar, R.
,
Freud, L.
,
Leibner, U.
in
Archaeology
,
Archaeology and Prehistory
,
archaeomagnetism
2024
The rich and extensively studied archaeological record of the Near East provides an opportunity to develop a comprehensive archaeomagnetic dataset for exploring the behavior of the geomagnetic field with high precision. The Levantine archaeomagnetic curve (LAC) project is an ongoing effort to develop a continuous high‐resolution geomagnetic intensity curve for the Levant and Mesopotamia. The first version of the LAC covered the period between 3000 and 550 BCE. Here, we report archaeointensity data from 169 samples compiled into 32 groups dating between the 7th and the 1st centuries BCE aiming at extending the LAC up to the end of the first millennium BCE. Twenty‐two groups are assembled from storage jar handles bearing different types of royal seal impressions, which were used in Judah as part of a taxation administrative system. These groups are combined with 10 other groups of pottery assemblages, three of which are from Hellenistic destruction layers dated using radiocarbon and coins. The new curve shows that the Levantine Iron Age Anomaly (LIAA) spanned 550 years (1100 ‐ 550 BCE) and that the rate of decline during the last spike around 600 BCE could have reached ∼0.6 μT/year. During the 6th century, the virtual axial dipole moment (VADM) dropped from 160 ZAm2 to 125 ZAm2 after which field intensity only slightly increased to 135 ZAm2, until another considerable decline to ∼90 ZAm2 during the 3rd to the 1st centuries BCE. We highlight the archaeomagnetic implication of the new curve in inferring the relative chronological relationship between different stamp types. Plain Language Summary The Earth's magnetic field is continuously changing both in time and space in an unpredictable manner. A detailed description of how the magnetic field has changed throughout Earth's history offers constraints on our understanding of the mechanism generating the field in Earth's core. In this study, we reconstruct the intensity of the past field using an assemblage of well‐dated archaeological materials from Israel, dated to the Assyrian, Babylonian, Persian, Hellenistic and Hasmonean periods. This work is part of an ongoing effort to procure a high‐resolution curve describing the changes in field intensity for the Levant and Mesopotamia over the past several millennia. With the new data, we calculate the curve for the first three millennia BCE. The curve provides further details on an anomalous behavior of the field between 1100 BCE and 550 BCE, termed the Levantine Iron Age Anomaly (LIAA), during which the field intensity and its rate of change were significantly higher than today's. In addition, the curve forms the basis for an archaeomagnetic dating tool, which can be especially useful for periods when traditional archaeological dating methods fail to provide precise ages due to large uncertainties in radiocarbon dates. Key Points Archaeomagnetic intensity data from 32 groups of pottery in Israel dated between the 7th and the 1st centuries BCE The second generation of the Levantine Archaeomagnetic Curve (LAC.v.2.0) covering the last three millennia BCE The new data constrain the duration of the Levantine Iron Age Anomaly (LIAA) from 1100 BCE to 550 BCE
Journal Article
Paleointensity Estimates From the Pleistocene of Northern Israel: Implications for Hemispheric Asymmetry in the Time‐Averaged Field
by
Shaar, R.
,
Tauxe, L.
,
Koppers, A. A. P.
in
Geomagnetic field
,
Geomagnetic field models
,
Holocene
2022
Twenty‐two sites, subjected to an IZZI‐modified Thellier‐Thellier experiment and strict selection criteria, recover a paleomagnetic axial dipole moment (PADM) of 62.2 ± 30.6 ZAm2 in Northern Israel over the Pleistocene (0.012–2.58 Ma). Pleistocene data from comparable studies from Antarctica, Iceland, and Hawaii, re‐analyzed using the same criteria and age range, show that the Northern Israeli data are on average slightly higher than those from Iceland (PADM = 53.8 ± 23 ZAm2, n = 51 sites) and even higher than the Antarctica average (PADM = 40.3 ± 17.3 ZAm2, n = 42 sites). Also, the data from the Hawaiian drill core, HSDP2, spanning the last half million years (PADM = 76.7 ± 21.3 ZAm2, n = 59 sites) are higher than those from Northern Israel. These results, when compared to Pleistocene results filtered from the PINT database (www.pintdb.org) suggest that data from the Northern hemisphere mid‐latitudes are on average higher than those from the southern hemisphere and than those from latitudes higher than 60°N. The weaker intensities found at high (northern and southern) latitudes therefore, cannot be attributed to inadequate spatiotemporal sampling of a time‐varying dipole moment or low quality data. The high fields in mid‐latitude northern hemisphere could result from long‐lived non‐axial dipole terms in the geomagnetic field with episodes of high field intensities occurring at different times in different longitudes. This hypothesis is supported by an asymmetry predicted from the Holocene, 100 kyr, and 5 million year time‐averaged geomagnetic field models. Plain Language Summary According to the Geocentric Axial Dipole hypothesis, the geomagnetic field may be approximated by a dipole that is aligned with the spin axis and positioned in the center of Earth. Such a field would produce field strengths that vary with respect to latitude with high latitudes associated with high intensities, or, converted to equivalent “virtual” dipole moments, would be essentially independent of latitude. It has long been suggested that high latitudes have had lower field strengths than predicted by such a model, when compared to data from mid‐latitudes, but these claims have always been accompanied by caveats regarding differences in temporal coverage or methodological approaches. Here, we present new data from Pleistocene aged rapidly cooled cinder cones and lava flow tops from Israel. We compare these data to other recent data sets obtained from rapidly cooled materials collected in Hawaii, Iceland, and Antarctica. These confirm that virtual dipole moments from mid northern hemisphere latitudes are higher than those from high latitudes and from the southern hemisphere. Global compilations spanning the Pleistocene, when filtered for quality also shows this behavior as do time averaged field models. Therefore, field strengths over even millions of years can have persistent non‐dipole field contributions. Key Points We present 26 40Ar/39Ar ages from volcanic rocks from Northern Israel (90 ka to 3.3 Ma) Twenty‐two Pleistocene intensity estimates have a mean paleomagnetic dipole moment of 62.2 ± 30.6 ZAm2 The northern hemisphere had persistently higher fields than the southern during the Pleistocene
Journal Article
Retinal Ependymoma: A Rare Extra-Axial Presentation
2020
Abstract
Introduction/Objective
Ependymomas are well-demarcated and slow-growing neuroepithelial neoplasms that comprise 3–9% of primary CNS tumors. The vast majority of ependymomas arise either intracranially, mostly in children, or in the spinal cord and are associated with ependymal lining. Histologic hallmarks are perivascular pseudorosettes, ependymal rosettes and alternating zones of nuclear crowding and nuclear free zones composed of coarse cell processes. In high grade ependymomas increased mitoses, necrosis and nuclear pleomorphism may be seen.
Methods
We present the case of a 63-year-old woman in with a past medical history of retinopathy of prematurity, glaucoma and right eye enucleation. She presented with a painful blind left eye refractory to medical treatment and subsequently underwent left eye enucleation.
Results
On histologic examination, an incidental retinal ependymoma was identified. The neoplastic cells were fusiform and had long coarsely fibrillar cell processes. Characteristic periodicity of nuclear crowding and scarcity was observed. In places, neoplastic cell processes extended radially to delicate and sometimes hyalinized blood vessels, forming so-called perivascular pseudorosettes. Definite ependymal rosettes were not recognized in the examined sections. Stigmata of chronicity were found, such as ischemic type necrosis, blood vessels with dystrophic calcifications and foci of ossification replete with fibroadipose tissue in the marrow spaces.
The neoplastic cells labeled with antibodies against glial fibrillary acidic protein (GFAP), thus confirming glial lineage in the neoplastic cell. Additionally, there was scattered intracytoplasmic expression of epithelial membrane antigen (EMA) in a dot-like or circular pattern. The latter is well described in ependymomas and often used to support the diagnosis.
Conclusion
Ependymomas rarely occur at extracranial sites, such as the chest, abdomen and pelvis. We are presenting the fourth case of retinal ependymoma reported in literature. The tumor had classical immunomorphologic findings.
Journal Article
Partial Nephrectomy For a Presumed Single Renal Mass Revealing Multiple Tumor Histologies: A Series of 4 Patients
2020
Abstract
Introduction/Objective
Renal mass biopsy is known to have a low but unavoidable diagnostic error rate. However, the occurrence of multiple adjacent masses mimicking one mass clinically has been minimally studied.
Methods
We report a series of four patients who were radiologically presumed to have a single renal mass and treated with partial nephrectomy, yet who were found to have multiple demarcated renal cell carcinoma histologies at pathologic evaluation.
Results
All were men aged 63–70 years. Grossly, tumors were red brown with scant, bright yellow foci in one of them. Dominant tumors followed by smaller tumors were: patient 1 - clear cell renal cell carcinoma (5.0 cm), clear cell papillary renal cell carcinoma (0.5 cm), and papillary adenoma (0.6 cm); patient 2 - clear cell renal cell carcinoma (1.5 cm) and clear cell papillary renal cell carcinoma (0.5 cm); patient 3 - papillary renal cell carcinoma (5.0 cm) and eosinophilic variant of chromophobe renal cell carcinoma (1.0 cm); patient 4 - chromophobe renal cell carcinoma (4.0 cm) and clear cell papillary renal cell carcinoma (0.6 cm). Immunohistochemical studies for cytokeratin 7, carbonic anhydrase IX, high molecular weight cytokeratin, CD10, and alpha-methyl acyl-CoA racemase (AMACR) confirmed the separate components in all.
Conclusion
This series adds to the spectrum of causes that may contribute to discordant results of renal mass biopsy and resection specimens. Secondary smaller tumors appear to be predominantly nonaggressive histologies, enriched for clear cell papillary renal cell carcinoma. Pathologists and urologists should be aware of this occurrence when considering the role of renal mass biopsy and interpreting the results.
Journal Article
Superior Capsular Reconstruction With a Long Head of the Biceps Tendon Autograft: A Cadaveric Study
2018
Background:
Several procedures have been proposed to address irreparable rotator cuff (RC) tears with pseudoparalysis. One recently proposed procedure is superior capsular reconstruction (SCR) using a tensor fasciae latae (TFL) autograft.
Hypothesis:
SCR with a locally available long head of the biceps tendon (LHB) autograft is biomechanically equivalent to SCR using TFL autograft for preventing superior humeral migration and the development of RC arthropathy in patients with irreparable RC tears.
Study Design:
Controlled laboratory study.
Methods:
Ten cadaveric shoulders (5 matched pairs) were tested. One shoulder from each pair was randomly assigned to the LHB reconstruction group using our novel technique, while the contralateral side was assigned to the TFL reconstruction group. SCR with a TFL autograft was performed based on previously described techniques. Massive RC tears were created by detachment of the supraspinatus and infraspinatus footprints from the greater tuberosity. The force required to superiorly translate the humerus 1.5 cm was then tested and recorded using a servohydraulic testing machine under 2 conditions: (1) after a massive RC tear and (2) after SCR with either a TFL autograft or an LHB autograft.
Results:
SCR with an LHB autograft required 393.2% ± 87.9% (P = .029) of the force needed for superior humeral migration in the massive RC tear condition, while SCR with a TFL autograft required 194.0% ± 21.8% (P = .0125). The LHB reconstruction group trended toward a stronger reconstruction when normalized to the torn condition (P = .059).
Conclusion:
SCR with an LHB autograft is a feasible procedure that is shown to be biomechanically equivalent and potentially even stronger than SCR with a TFL autograft in the prevention of superior humeral migration.
Clinical Relevance:
This new technique may help to prevent superior humeral migration and the development of RC arthropathy in patients with irreparable RC tears.
Journal Article
The Proximal and Distal Effects of Blood Flow Restriction Therapy on Upper and Lower Extremity Strengthening: A Randomized Controlled Trial
by
Milligan, Heather
,
Brown, Patty
,
Bowman, Eric N.
in
Blood diseases
,
Clinical trials
,
Orthopedics
2019
Objectives:
Blood flow restriction (BFR) therapy consists of low-intensity exercise performed under reduced venous return due to an inflatable tourniquet. This produces similar physiologic and clinical effects to high-intensity routines with less joint and tissue stress. Postoperative patients may benefit from more efficient rehabilitation. Proximal and distal effects of BFR have been evaluated, however, minimal literature exists on its use in orthopaedic conditions. The purpose of this study was to determine the effects of low-intensity BFR therapy both proximal and distal, in the upper and lower extremities.
Methods:
This was a prospective, randomized controlled trial of healthy subjects completing a standardized 6-week course of BFR therapy. Subjects were randomized to BFR therapy on one extremity or to a control group. Subjects were excluded for cardiac, pulmonary, or hematologic disease, pregnancy, or previous surgery in the extremity. Data collected at baseline and completion included: limb circumferences, isokinetic, and manual strength testing.
Results:
Forty subjects completed the protocol. Average age was 27.7 years; 54% were female. For both upper and lower extremity groups, a statistically significant increase was observed in manual and isokinetic strength both proximal and distal to the BFR tourniquet when compared to both the non-tourniquet extremity and the control group (p<0.05). Limb circumference significantly increased in the upper (p<0.01) and lower extremities (p=0.02). A significant increase in manual strength was noted in shoulder abduction and scaption, and hip extension and abduction even in the non-tourniquet BFR extremity compared to the control group (p<0.05).
Conclusion:
Low-intensity BFR therapy led to greater increases in muscle strength and hypertrophy. Similar strengthening effects were seen in proximal and distal muscle groups. Strength increases in the contralateral BFR extremity may corroborate a systemic effect. This study provides data to further evaluate the efficacy and safety of BFR therapy in operative and non-operative orthopaedic conditions.
The mean percent increase and comparison between the BFR tourniquet limb and control group with p-values.
LOWER EXTREMITY
Controln=20
BFR limbn=16
p
UPPER EXTREMITY
Controln=20
BFR Limbn=14
p
Circumference
Circumference
Thigh
0.8
3.5
<0.001
Arm
2.5
5.2
<0.001
Leg
0.4
2.8
0.001
Forearm
1.4
4.2
<0.001
Strength
Strength
Knee extension
Shoulder IR
Total work
6
15
0.046
Total work
0.1
12
0.043
Peak torque
3
11
0.018
Peak torque
7
16
0.018
Power
4
12
0.015
Avg Power
2
20
0.078
Knee flexion
Shoulder ER
Total work
14
27
0.044
Total work
12
15
0.389
Peak torque
5
11
0.173
Peak torque
2
10
0.041
Power
7
13
0.135
Avg Power
15
24
0.188
Hip abduction
27
46
0.021
Shoulder Scaption
18
48
0.021
Hip extension
42
60
0.046
Shoulder Flexion
16
39
0.001
Plantar flexion
18
33
0.018
Shoulder Abd
8
33
0.001
Heel raises
4
28
<0.001
Elbow Flexion
29
52
0.047
Elbow Extension
35
43
0.242
Grip Strength
0.4
9
0.002
Journal Article
Quantitative vectorial magnetic imaging of multi domain rock forming minerals using nitrogen-vacancy centers in diamond
Magnetization in rock samples is crucial for paleomagnetometry research, as it harbors valuable geological information on long term processes, such as tectonic movements and the formation of oceans and continents. Nevertheless, current techniques are limited in their ability to measure high spatial resolution and high-sensitivity quantitative vectorial magnetic signatures from such samples. As a result, our understanding of this magnetization is limited, specifically for the case of multi-domain samples. In this work we use a newly developed nitrogen-vacancy magnetic microscope, capable of quantitative vectorial magnetic imaging with optical resolution. We demonstrate direct imaging of the vectorial magnetic field of a single, multi-domain dendrite, as well as the measurement and calculation of the weak magnetic moments of individual grains on the micron scale. These results pave the way for future applications in paleomagnetometry, and for the fundamental understanding of magnetization in multi-domain samples.
Lifestyle intervention in early pregnancy can prevent gestational diabetes in high-risk pregnant women in the UAE: a randomized controlled trial
by
Adnan, Rama
,
Tesfa, Yohannes
,
Jakapure, Vidya
in
Body mass index
,
Data collection
,
Diabetes, Gestational - epidemiology
2022
Purpose
A prevalence of gestational diabetes mellitus (GDM) is approximately three times higher than the global rate in the UAE. However, it has not yet been studied whether a 12-week moderate-intensity lifestyle intervention can prevent gestational diabetes among pregnant women at high risk in this region.
Patients and methods
A pragmatic, open-label, randomized clinical trial was conducted.
Sixty-three women aged 18 to 45 years, with ≤12 weeks of gestation, singleton pregnancy, and having ≥ two risk factors for GDM were randomly assigned to the Lifestyle Intervention (LI) group (
n
= 30) or Usual Care (UC) group (
n
= 33). The women in the LI group received a 12-week, moderate-intensity lifestyle intervention with individualized counseling on a diet, physical activity, and behavior change by a licensed dietitian. The women in the UC group received usual antenatal care. The primary outcome was the incidence of GDM based on the IADPSG criteria at 24-28 weeks of gestation.
Results
The incidence of GDM was 33.3% in LI group and 57.5% in UC group. The crude relative risk (RR) for GDM was 0.59 (95% CI, 0.32-1.04,
p
= 0.05). The multivariable logistic regression model without adjustment showed OR = 0.37 (95% CI, 0.13-1.02,
p
= 0.05) and after adjusting with Age, BMI and family history of diabetes reported OR = 0.26, 95%CI 0.07, 0.92,
p
= 0.04. in LI vs UC. The daily dietary intake of calories (− 120 kcal,
p
= < 0.01), carbohydrates (− 19 g,
p
< 0.01), and fat (− 5 g,
p
= 0.03) was reduced, and physical activity time (+ 52 min,
p
= 0.05) increased in the LI group after the intervention. However, the LI had no significant effect on maternal and neonatal outcomes.
Conclusion
A 12-week moderate intensity lifestyle intervention in early pregnancy could reduce the relative risk of GDM by 41% among high-risk pregnant women in the UAE. These findings could impact public health outcomes in the region.
Trial registration
Trial registration Retrospectively registered NCT04273412
,18/02/2020
.
Journal Article
CYP2R1 polymorphisms are important modulators of circulating 25-hydroxyvitamin D levels in elderly females with vitamin insufficiency, but not of the response to vitamin D supplementation
2017
SummaryWe studied the association between CYP2R1 genetic polymorphisms and circulating 25-hydroxyvitamin D [25(OH)D] before and after supplementation with vitamin D3 in 218 elderly. We found differences between 3 and 8 ng/ml in circulating levels at baseline in women but not in the response after 1 year of supplementation.IntroductionThis study evaluated the association between polymorphisms in four single nucleotide polymorphisms (SNPs) of the CYP2R1 gene and 25(OH)D levels before and 1 year after supplementation with two different doses of vitamin D3 (600 IU daily or a dose equivalent to 3750 IU daily), in a cohort of 218 (96 men and 122 women) Lebanese elderly overweight subjects.MethodsGenotyping was performed for rs12794714, rs10741657, rs1562902, and rs10766197 SNPs using real-time PCR. The 25(OH)D levels were measured by liquid chromatography tandem mass spectrometry.ResultsAt baseline, the mean ± SD age was 71.0 ± 4.7 years, BMI 30.3 ± 4.6 kg/m2, and 25(OH)D level was 20.5 ± 7.6 ng/ml. There were significant differences in mean 25(OH)D levels between genotypes in women, but not in men. After adjustment for age, season, and BMI, the homozygous for the low frequency gene variant (HLV) of rs1562902 and rs10741657 SNPs had the highest mean 25(OH)D levels with difference of 7.6 ng/ml for rs1562902 SNP (p < 0.01) and of 5.9 ng/ml for rs10741657 (p = 0.05) compared to the homozygous for the major polymorphisms (HMPs). Conversely, for rs10766197 and rs12794714 SNPs, HMP had the highest mean 25(OH)D levels with difference of 6 ng/ml for rs10766197 (p = 0.003) and of 4.8 ng/ml (p = 0.02) for rs12794714, compared to the HLV. CYP2R1 genetic polymorphisms explained 4.8 to 9.8 % of variability in 25(OH)D in women. After 1 year, there was no difference in the response to vitamin D3 supplementation between genotypes in either gender.ConclusionThis study showed a difference in 25(OH)D levels between CYP2R1 genotypes that equates a daily supplementation of 400–800 IU vitamin D, depending on genotype. It underscores possible important genetic contributions for the high prevalence of hypovitaminosis D in the Middle East.
Journal Article
Comparison of Transmyocardial Revascularization with Medical Therapy in Patients with Refractory Angina
by
Angell, William W
,
Allen, Keith B
,
Petracek, Michael R
in
Aged
,
Angina pectoris
,
Angina Pectoris - classification
1999
Despite the success of current medical and surgical management of ischemic heart disease, a growing number of patients have diffuse obstructive coronary artery disease that is not amenable to coronary-artery bypass grafting or catheter-based interventions. This problem has stimulated interest in developing alternative therapeutic approaches. Early attempts at indirect myocardial revascularization had limited success. Beck's use of omentopexy, reported in 1935,
1
and Vinberg's use of thoracic-artery implantation, reported in 1954,
2
were attempts to provide direct myocardial perfusion and were based on the description by Wearn et al., in 1933,
3
of a sinusoidal network in the human heart. In 1965, Sen . . .
Journal Article