Understanding the factors underlying the interaction of water with oxide surfaces is of high technological importance for applications ranging from nuclear fuel safety to heterogeneous catalysis.However,it is a comple...Understanding the factors underlying the interaction of water with oxide surfaces is of high technological importance for applications ranging from nuclear fuel safety to heterogeneous catalysis.However,it is a complex task as numerous different factors(related to the surface and bulk properties)are involved.In the present study,we investigated the characteristics of water adsorption(quantities adsorbed and energetics)on binary oxides of fluorite structure and their mixed oxide combinations(solid solutions).Three representative oxides were chosen,differing in lattice parameter(ionic radius)and oxidation state:ThO_(2)which has a very stable Th^(4+)cation,CeO_(2)in which the cerium cations can be easily reduced to Ce^(3+),and UO_(2)in which the uranium cations tend to further oxidize to U^(5+)and U^(6+).Based on the H_(2)O adsorption isotherms and enthalpies of adsorption versus coverage,combined with X-ray photoelectron spectroscopy(XPS)study of the oxide surface,the main factors underlying the characteristics of water adsorption on the fluorite oxides were identified.The present work points to the importance of oxygen hyper-stoichiometry(in U-containing oxides)on the interaction of water with the oxide’s surface.Furthermore,correlations between Fermi level positioning and water dissociation tendencies are established.This work advances our understanding of water-oxide interactions with implications for material design in energy and environmental systems.展开更多
The SafeAmpCase is an innovative 3D-printed solution developed to address critical challenges in transporting and storing fragile glass drug ampoules during emergencies.This study employs a multidisciplinary approach...The SafeAmpCase is an innovative 3D-printed solution developed to address critical challenges in transporting and storing fragile glass drug ampoules during emergencies.This study employs a multidisciplinary approach—integrating biomedical engineering,advanced materials science,and emergency medicine expertise—to develop a compact,durable,and user-friendly ampoule case.A key innovation lies in the strategic selection of thermoplastic polyurethane(TPU)as the material,leveraging its superior impact resistance,flexibility,and noise-damping characteristics to ensure reliability under performance in demanding real-world conditions.To optimize the 3D printing process,key parameters,including printing temperature(220-250℃),volumetric flow rate(3-20 mm^(3)/s),retraction speed(30-90 mm/s),and retraction length(0.4-1.2 mm),were systematically adjusted using calibration models.The final optimized parameters(245℃,7 mm^(3)/s,90 mm/s,and 1.2 mm)reduced production time by 43%while preserving structural integrity.American Society for Testing and Materials(ASTM)international standard drop tests confirmed the case’s exceptional impact resistance,demonstrating a 90%reduction in ampoule breakage compared to polylactic acid plus.Further refinements,guided by feedback from 25 emergency professionals,resulted in medicationspecific color coding and an enhanced locking mechanism for usability in high-pressure situations.The final SafeAmpCase model withstood 18 consecutive drop trials without ampoule breakage,confirming its robustness in field conditions.This research underscores the transformative potential of additive manufacturing in developing customized,high-performance solutions for critical healthcare applications,setting a new benchmark for biomedical device design and rapid prototyping.展开更多
BACKGROUND Type 1 diabetes mellitus(T1DM)is an autoimmune disease with a multifactorial pathogenesis.Viral infections have been proposed as contributing triggers,supported by the disease’s seasonal pattern,which typi...BACKGROUND Type 1 diabetes mellitus(T1DM)is an autoimmune disease with a multifactorial pathogenesis.Viral infections have been proposed as contributing triggers,supported by the disease’s seasonal pattern,which typically shows higher incidence in autumn and winter.The coronavirus disease 2019(COVID-19)pandemic and associated lockdowns created a unique context to examine the incidence and seasonality of T1DM during a period characterized by reduced circulation of common viral infections.AIM To investigate the incidence and seasonality of T1DM before and during COVID-19 pandemic in relation to global viral infection rates.METHODS This population-based retrospective study utilized a nationwide computerized database.Extracted data included the number of new T1DM cases over the 8 years preceding and during the COVID-19 pandemic,demographic characteristics of affected individuals,and nationwide respiratory virus polymerase chain reaction data from weekly nasal wash sample collections.RESULTS A total of 2176 patients were diagnosed with new-onset T1DM during the prepandemic period,compared to 348 cases during the pandemic.In the same periods,33727 respiratory virus-positive polymerase chain reaction results from nasal wash samples were recorded pre-pandemic,compared to 2603 during the pandemic.Additionally,363399 positive COVID-19 cases were reported during the pandemic period.Seasonality analysis revealed a higher rate of new-onset T1DM cases and a weaker seasonal pattern during the pandemic.Trend analysis showed a consistent increase in T1DM incidence prior to COVID-19,with a more variable trend observed during the pandemic.Correlation analysis between T1DM incidence and respiratory viruses demonstrated a weak correlation between T1DM incidence and a few respiratory viruses.CONCLUSION The observed increase in new-onset T1DM cases and the disruption of its typical seasonal pattern during the COVID-19 pandemic suggest a potential association between respiratory virus exposure and the development of T1DM.展开更多
Spermatogenesis is a complex process regulated by endocrine and testicular paracrine/autocrine factors. Gonadotropins are involved in the regulation of several testicular paracrine factors, mainly of the IL-1 family a...Spermatogenesis is a complex process regulated by endocrine and testicular paracrine/autocrine factors. Gonadotropins are involved in the regulation of several testicular paracrine factors, mainly of the IL-1 family and testicular hormones. Testicular cytokines and growth factors (such as IL-1, IL-6, TNF, IFN-γ, LIF and SCF) were shown to affect both the germ cell proliferation and the Leydig and Sertoli cells functions and secretion. Cytokines and growth factors are produced by immune cells and in the interstitial and seminiferous tubular compartments by various testicular cells, including Sertoli, Leydig, peritubular cells, spermatogonia, differentiated spermatogonia and even spermatozoa. Corresponding cytokine and growth factor receptors were demonstrated on some of the testicular cells. These cytokines also control the secretion of the gonadotropins and testosterone in the testis. Under pathological conditions the levels of pro-inflammatory cytokines are increased and negatively affected spermatogenesis. Thus, the expression levels and the mechanisms involved in the regulation of testicular paracrine/autocrine factors should be considered in future therapeutic strategies for male infertility.展开更多
Establishment of an in vitro system that allows the development of testicular germ cells to sperm will be valuable for studies of spermatogenesis and future treatments for male infertility. In the present study, we de...Establishment of an in vitro system that allows the development of testicular germ cells to sperm will be valuable for studies of spermatogenesis and future treatments for male infertility. In the present study, we developed in vitro culture conditions using three-dimensional agar culture system (SACS), which has the capacity to induce testicular germ cells to reach the final stages of spermatogenesis, including spermatozoa generation. Seminiferous tubules from testes of 7-day-old mice were enzymatically dissociated, and intratubular cells were cultured in the upper layer of the SACS in RPMI medium supplemented with fetal calf serum (FCS). The lower layer of the SACS contained only RPMI medium supplemented with FCS. Colonies in the upper layer were isolated after 14 and 28 days of culture and were classified according to their size. Immunofluorescence and real-time PCR were used to analyse specific markers expressed in undifferentiated and differentiated spermatogonia (Vasa, Dazl, OCT-4, C-Kit, GFR- a-l, CD9 and a-6-integrin), meiotic cells (LDH, Crem-1 and Boule) and post-meiotic cells (Protamine-1, Acrosin and SP-IO). Our results reveal that it is possible to induce mouse testicular pre-meiotic germ cell expansion and induce their differentiation to spermatozoa in SACS. The spermatozoa showed normal morphology and contained acrosomes. Thus, our results demonstrate that SACS could be used as a novel in vitro system for the maturation of pre-meiotic mouse germ cells to post-meiotic stages and morphologically-normal spermatozoa.展开更多
Two types of cyanobacteria of the genus Arthrospira(commonly known as Spirulina) were tested for biosorption of cerium(III) ions from aqueous solutions. An endemic type(ES) found in the northern Negev desert, Is...Two types of cyanobacteria of the genus Arthrospira(commonly known as Spirulina) were tested for biosorption of cerium(III) ions from aqueous solutions. An endemic type(ES) found in the northern Negev desert, Israel, and a commercial powder(CS) were used in this study. Biosorption was evaluated as a function of p H, contact time, initial metal concentration, number of sorption-desorption cycles, and salt concentration. The optimum p H range for biosorption was found to be 5.0–5.5. The kinetic characteristics of both Spirulina types were found to be highly compatible with a pseudo-second order kinetic model. The adsorption isotherms of both types were found to be well-suited to Langmuir and Freundlich adsorption isotherms. Maximum biosorption uptakes, according to the Langmuir model, were 18.1 and 38.2 mg/g, for ES and CS, respectively. Sodium chloride concentrations of up to 5 g/L had a minor effect on cerium biosorption. Desorption efficiency was found to be greater than 97% with 0.1 mol/L HNO_3 after three sorption-desorption cycles, without significant loss in the biosorption capacity. The results indicated the feasibility of cerium recovery from industrial wastes using Spirulina biomass.展开更多
Explosive Reactive Armor was originally modeled under the assumption that the plates in the cassettes were very thin.Hence their thickness could be ignored,and the thicknesses of the plates were considered only based ...Explosive Reactive Armor was originally modeled under the assumption that the plates in the cassettes were very thin.Hence their thickness could be ignored,and the thicknesses of the plates were considered only based on their areal mass density.In particular,it was assumed that the jet-plate interaction was controlled by the plates to jet-mass-flux ratio criteria for a specific jet velocity and diameter.In the present study,we extended this analysis,examining the effect of the variation of the mass-flux along the jet on the disruption effect by the two plates.In addition,we examined the thickness effect of the plates on the plate's effectiveness,replacing the steel plates by low-density materials like aluminum and polycarbonate.The mass-flux model was adjusted to account for the plate-thickness effect.It was found that increasing the thickness of the plate,keeping the areal weight unchanged,slightly increases the overall effectiveness of the cassette,in particular by the forward moving plate interacting with the center and the slow parts of the jet.展开更多
In vitro culture of spermatogonial stem cells (SSCs) has generally been performed using two-dimensional (2D) culture systems; however, such cultures have not led to the development of complete spermatogenesis. It ...In vitro culture of spermatogonial stem cells (SSCs) has generally been performed using two-dimensional (2D) culture systems; however, such cultures have not led to the development of complete spermatogenesis. It seems that 2D systems do not replicate optimal conditions of the seminiferous tubules (including those generated by the SSC niche) and necessary for spermatogenesis. Recently, one of our laboratories has been able to induce proliferation and differentiation of mouse testicular germ cells to meiotic and postmeiotic stages including generation of sperm in a 3D soft agar culture system (SACS) and a 3D methylcellulose culture system (MCS). It was suggested that SACS and MCS form a special 3D microenvironment that mimics germ cell niche formation in the seminiferous tubules, and thus permits mouse spermatogenesis in vitro. In this review, we (1) provide a brief overview of the differences in spermatogenesis in rodents and primates, (2) summarize data related to attempts to generate sperm in vitro, (3) report for the first time formation of colonies/clusters of cells and differentiation of meiotic (expression of CREM-1) and postmeiotic (expression of acrosin) germ cells from undifferentiated spermatogonia isolated from the testis of prepubertal rhesus monkeys and cultured in SACS and MCS, and (4) indicate research needed to optimize 3D systems for in vitro primate spermatogenesis and for possible future application to man.展开更多
An initiation study is presented in which we examine the effect of the normal and the tangential velocity components of a fragment that impacts a covered and a bare Comp-B explosive. The study is based on calibrated n...An initiation study is presented in which we examine the effect of the normal and the tangential velocity components of a fragment that impacts a covered and a bare Comp-B explosive. The study is based on calibrated numerical Lagrangian simulations using the LS-Dyna hydrocode. A special procedure was developed to present the estimated initiation point and the shock wave transition into detonation for various impact angles. The influence of the fragment strength and the steel cover thickness on the detonation threshold were also examined. The velocity threshold results are presented and used to modify the Jacobs-Roslund initiation model.展开更多
The paper deals with the problem of the distribution of the medicine (enzyme) in the damaged biological tissue where the reaction enzyme—substrat takes place. The biological problem is reduced to a singular degenerat...The paper deals with the problem of the distribution of the medicine (enzyme) in the damaged biological tissue where the reaction enzyme—substrat takes place. The biological problem is reduced to a singular degenerate initial-boundary value problem for two coupled ordinary differential equations. Analytical solution of the singular degenerated IBV-problem was obtained by power series. The solution demonstrates the real situation and found suitable to depict the degeneration of singular system, caused by low concentration of the enzyme.展开更多
The effect of radio-frequency (RF) or low-frequency (LF) bias voltage on the for- mation of amorphous hydrogenated carbon (a-C:H) films was studied on silicon substrates with a low methane (CH4) concentration...The effect of radio-frequency (RF) or low-frequency (LF) bias voltage on the for- mation of amorphous hydrogenated carbon (a-C:H) films was studied on silicon substrates with a low methane (CH4) concentration (2-10 vol.%) in CH4+Ar mixtures. The bias substrate was applied either by RF (13.56 MHz) or by LF (150 kHz) power supply. The highest hardness values (~18-22 GPa) with lower hydrogen content in the fihns (~20 at.%) deposited at 10 vol.% CH4, was achieved by using the RF bias, However, the films deposited using the LF bias, under similar RF plasma generation power and CH4 concentration (50 W and 10 vol.%, respectively), displayed lower hardness (~6-12 GPa) with high hydrogen content (~40 at.%). The structures analyzed by Fourier Transform Infrared (FTIR) and Raman scattering measurements provide an indication of trans-polyacetylene structure formation. However, its excessive formation in the films deposited by the LF bias method is consistent with its higher bonded hydrogen concentration and low level of hardness, as compared to the film prepared by the RF bias method. It was found that the effect of RF bias on the film structure and properties is stronger than the effect of the low-frequency (LF) bias under identical radio-frequency (RF) powered electrode and identical PECVD (plasma enhanced chemical vapor deposition) system configuration.展开更多
Objective:To investigate the effects of a dry aqueous extract of Notobasis syriaca(N.syriaca)on lipopolysaccharide(LPS)-induced inflammation in rats.Methods:Rats were fed the dried extract[500 mg/(kg·d)]for three...Objective:To investigate the effects of a dry aqueous extract of Notobasis syriaca(N.syriaca)on lipopolysaccharide(LPS)-induced inflammation in rats.Methods:Rats were fed the dried extract[500 mg/(kg·d)]for three consecutive days and then were intraperitoneally injected with LPS(1 mg/kg).Two hours after LPS injection,rats were sacrificed and blood and brain regions were collected.Inflammatory mediators'levels in plasma and homogenates of brain regions were determined by ELISA.Results:Pretreatment with the N.syriaca extract resulted in significant anti-inflammatory effects(P<0.05),including:(i)attenuated LPS-induced hypothermia;(ii)decreased hypothalamus and hippocampus prostaglandin E_(2)levels in the LPStreated rats;and,(iii)reduced hypothalamus and hippocampus interleukin-6 and tumor necrosis factor-a levels in the LPS-treated rats.Conclusions:These results suggest that N.syriaca possesses anti-inflammatory properties.Thus,it is possible that long-term consumption of this plant may result in beneficial pharmacological effects.展开更多
AIM: To investigate the prevalence and clinical characteristics of Helicobacter pylori(H.pylori)-infected dyspeptic patients with selective immunoglobulin E deficiency(IgE d).METHODS: All individuals who underwent ser...AIM: To investigate the prevalence and clinical characteristics of Helicobacter pylori(H.pylori)-infected dyspeptic patients with selective immunoglobulin E deficiency(IgE d).METHODS: All individuals who underwent serum totalimmunoglobulin E(Ig E) measurement at the Leumit Healthcare Services(Israel) in 2012 were identified in an electronic database search(n = 18487).From these,selected case group subjects were ≥ 12 years of age and had serum total Ig E < 2 k IU/L(n = 158).The control group was selected from a random sampling of the remaining subjects ≥ 12 years of age to obtain a case-control ratio of 1:20(n = 3160).Dyspeptic diseases,diagnosed no more than 5 years before serum total Ig E testing,were identified and retrieved from the electronic database using specific International Classification of Diseases diagnostic codes.Results of C13-urea breath tests were used to identify subjects infected with H.pylori.Categorical variables between case and control subjects were analyzed using Fisher's exact tests,whereas continuous variables were analyzed using χ2 tests.RESULTS: Dyspepsia was present in 27.2%(43/158) of case subjects and 22.7%(718/3160) of controls.Of these,significantly more case subjects(32/43,74.4%) than controls(223/718,31.1%) were positive for H.pylori(P < 0.01).Esophagogastroduodenoscopy was performed in 19 case and 94 control subjects,revealing that gastritis was more prevalent in IgE d case subjects than in controls(57.9% vs 29.8%,P < 0.05).Furthermore,a significantly greater proportion of case subjects presented with peptic duodenal ulcers(63.2% vs 15.9%,P < 0.01).Histopathologic examination showed marked chronic inflammation,lymphoid follicle formation and prominent germinal centers,with polymorphonuclear cell infiltration of gastric glands,that was similar in case and control biopsy tissues.Finally,Ig Ed case subjects that underwent esophagogastroduodenoscopy were more likely to exhibit treatment-refractory H.pylori infections that require second-line triple antibiotic therapy(47.4% vs 11.7%,P < 0.01).CONCLUSION: IgE d is associated with higher rates ofH.pylori-associated gastritis and peptic duodenal ulcers.展开更多
Spindle-cell lipoma (SCL) is a variant of lipoma, usually presenting in the neck or trunk. SCL of the oral cavity is rare. Some cases of oral SCL have been reported;however, the clinico-pathologic characteristics of o...Spindle-cell lipoma (SCL) is a variant of lipoma, usually presenting in the neck or trunk. SCL of the oral cavity is rare. Some cases of oral SCL have been reported;however, the clinico-pathologic characteristics of oral SCL are still unknown. Here we report on 2 cases and review 33 cases of oral SCL published in the literature. The patients were 23 men and 12 women, with a mean age of 55 years (range 23 - 88 years);there were no children. Tumor sites included: tongue (n = 13), cheek/buccal mucosa (n = 11), floor of mouth (n = 5), lip (n = 2), hard palate (n = 2), alveolar ridge (n = 1), and maxilla (n = 1). The mean tumor size was 20.87 mm (range 3 - 50 mm), smaller than extra-oral lesions. Thirty-three patients (94%) presented with a single lesion that was circumscribed and composed of mature adipocytes admixed with bland spindle cells. The spindle cells were strongly immunoreactive for CD34, whereas the adipocytes were negative. The main differential diagnosis is atypical lipoma/well-differentiated liposarcoma. All lesions underwent local excision and recurrences are rare. Oral SCL do not seem to differ from their extra-oral counterpart, which are much more common and larger in size. SCL should be included in the differential diagnosis of oral cavity mesenchymal tumors.展开更多
Background: Epstein Barr Virus (EBV) is associated with different kinds of tumors. In the present study we tried to understand its role in pediatric MDS of a 4-year-old girl with EBV infection and MDS with refractory ...Background: Epstein Barr Virus (EBV) is associated with different kinds of tumors. In the present study we tried to understand its role in pediatric MDS of a 4-year-old girl with EBV infection and MDS with refractory anemia and monosomy 7. Procedures: The work-up included: hematological tests;serology for IgM, IgG antibodies to EBV;PCR for EBV;cytogenetics of bone marrow (BM), and FISH analysis of BM and blood;immunohistochemistry-LMP1 expression on BM smears. Results: Hematological follow up showed constant mild dysplastic changes mostly in the erythroid lineage. PCR for EBV showed positive results in the nasopharygeal smears as well as in blood 15 weeks after disease onset. Cytogenetic analysis showed monosomy7 inall the mitoses of BM sample. Fluorescence in situ hybridization (FISH) showed monosomy 7% in 57% of the cells, followed by a decreased tendency in the percentage of monosomy 7 cells in both BM and blood. Immunohistochemistry for EBV-latent membrane protein 1 (LMP-1) on the patient’s BM smears, 21 weeks post disease onset, showed 9% positive cells, 80% of them carried monosomy 7. Conclusion: The parallel occurrence of the EBV infection and MDS, as well as the continuous EBV PCR positive and monosomy 7, support the possibility that they are related.展开更多
In assessing the relationship between calcium supplementation and maintaining bone mass or reducing the risk of fracture, the effectiveness of calcium supplementation has never been decisive. Freshwater crayfish rely ...In assessing the relationship between calcium supplementation and maintaining bone mass or reducing the risk of fracture, the effectiveness of calcium supplementation has never been decisive. Freshwater crayfish rely on amorphous calcium carbonate (ACC), an instable polymorph of calcium carbonate, as the main mineral in the exoskeleton and in the temporary storage organ, the gastrolith. Inspired by the crayfish model, we have previously shown an increase in calcium bioavailability in rats administered with synthetic stable ACC vs. crystalline calcium carbonate (CCC). The current study compared the effects of amorphous calcium derived from either gastrolith or synthetic ACC with those of crystalline calcium, found in commercial CCC or calciumcitrate supplements, in a bone loss prevention model. Rats were subjected to either sham or ovariectomy (OVX) operation (n^20/ group) followed by administration of food pellets supplemented with 0.5% calcium from either source over 12 weeks. Micro-computed tomography (μCT) and histomorphometric analyses revealed bone loss prevention by both gastrolith and ACC treatments, manifested by an increase in morphometric bone parameters, compared to both CCC-?and calcium citrate-treated groups. Both gastrolith and ACC treatments resulted in bone formation in the tibia cancellous bone, indicated by dynamic histomorphometry parameters, compared to either the CCC or calcium citrate treatments. Levels of urine deoxypyridinoline (DPD), suggested an anti-resorptive effect of ACC, which was also the only treatment that led to a significant increase in vertebral mechanical strength, as supported by μCT analysis of topology and orientation parameters of the vertebral trabeculae. To our knowledge, such levels of bone loss prevention by calcium supplements have never been reported. These findings thus suggest the potential of both natural (crayfish gastrolith) and, to a greater extent, synthetic ACC sources for the prevention of metabolic bone disorders and possibly of osteoporotic processes.展开更多
Purpose: Cylindrical ionization chambers as the PinPoint and the CC01 have high-spatial resolution and cylindrical symmetry in relevance to small fields. Dosimetry of newly advanced technologies that include non-copla...Purpose: Cylindrical ionization chambers as the PinPoint and the CC01 have high-spatial resolution and cylindrical symmetry in relevance to small fields. Dosimetry of newly advanced technologies that include non-coplanar beams, such as in Gamma-Knife, VMAT and IMRT treatment plans, the angular dependence of the ion chamber is essential. Therefore in this study we simulated two common used ion chambers using a Monte Carlo method. Methods: The angular dependence for the CC01 and the PinPoint were calculated for a vast angular range in a cylindrical water phantom for two LINAC photon beams, 6 MV and 15 MV. The calculations were performed for fully structural description of each ion chamber using Monte Carlo code, in order to reveal unsymmetrical response dose higher than 2% in medical applications. The calculated dose response, for the CC01 ion chamber, was validated with measurements. Results: The CC01 ion chamber showed a very small angular dependence compared to the PinPoint ion chamber. The relative angular dependence amplitude of the PinPoint was about 12% in the range of 0° - 110°. Conclusions: The differences in the ion chambers structure led to the variations in the relative angular dependence amplitude. Therefore, when choosing a detector, not only the volume of the ionization chamber but also its structure must be taken into consideration.展开更多
Poly(3-hexylthiophene)(P3HT) is a low-cost polymer donor for organic solar cells (OSCs). However, the P3HT-based OSCs usually give low power conversion efficiencies (PCEs) due to the wide bandgap and the high-lying en...Poly(3-hexylthiophene)(P3HT) is a low-cost polymer donor for organic solar cells (OSCs). However, the P3HT-based OSCs usually give low power conversion efficiencies (PCEs) due to the wide bandgap and the high-lying energy levels of P3HT. To solve this problem, in this work, we design and synthesize a new A-D-A type non-fullerene acceptor, DFPCBR, which owns an electron-donating (D) core constructed by linking a 2,5-difluorobenzene ring with two cyclopentadithiophene moieties, and two electron-accepting (A) end-groups of benzo[c][1,2,5]thiadiazole connected with 3-ethyl-2-thioxothiazolidin-4-one. Because of the strong electron-donating ability and large conjugation effect of D core, DFPCBR shows appropriate energy levels and a narrow bandgap matching well with those of P3HT. Therefore, with P3HT as the donor and DFPCBR as the acceptor, the OSCs possess broad absorption range from 350 nm to 780 nm and the reduced energy loss (Eloss) of 0.79 eV (compared with ~1.40 eV for the P3HT:PC61BM device), providing a good PCE of 5.34% with a high open-circuit voltage (VOC) of 0.80 V. Besides, we observe that the photovoltaic performances of these devices are insensitive to the thickness of the active layers:even if the active layer is as thick as 320 nm,~80%of the best PCE is maintained, which is rarely reported for fullerene-free P3HT-based OSCs, suggesting that DFPCBR has the potential application in commercial OSCs in the future.展开更多
基金Open access funding provided by Ben-Gurion University
文摘Understanding the factors underlying the interaction of water with oxide surfaces is of high technological importance for applications ranging from nuclear fuel safety to heterogeneous catalysis.However,it is a complex task as numerous different factors(related to the surface and bulk properties)are involved.In the present study,we investigated the characteristics of water adsorption(quantities adsorbed and energetics)on binary oxides of fluorite structure and their mixed oxide combinations(solid solutions).Three representative oxides were chosen,differing in lattice parameter(ionic radius)and oxidation state:ThO_(2)which has a very stable Th^(4+)cation,CeO_(2)in which the cerium cations can be easily reduced to Ce^(3+),and UO_(2)in which the uranium cations tend to further oxidize to U^(5+)and U^(6+).Based on the H_(2)O adsorption isotherms and enthalpies of adsorption versus coverage,combined with X-ray photoelectron spectroscopy(XPS)study of the oxide surface,the main factors underlying the characteristics of water adsorption on the fluorite oxides were identified.The present work points to the importance of oxygen hyper-stoichiometry(in U-containing oxides)on the interaction of water with the oxide’s surface.Furthermore,correlations between Fermi level positioning and water dissociation tendencies are established.This work advances our understanding of water-oxide interactions with implications for material design in energy and environmental systems.
基金Open access funding provided by Ben-Gurion University.
文摘The SafeAmpCase is an innovative 3D-printed solution developed to address critical challenges in transporting and storing fragile glass drug ampoules during emergencies.This study employs a multidisciplinary approach—integrating biomedical engineering,advanced materials science,and emergency medicine expertise—to develop a compact,durable,and user-friendly ampoule case.A key innovation lies in the strategic selection of thermoplastic polyurethane(TPU)as the material,leveraging its superior impact resistance,flexibility,and noise-damping characteristics to ensure reliability under performance in demanding real-world conditions.To optimize the 3D printing process,key parameters,including printing temperature(220-250℃),volumetric flow rate(3-20 mm^(3)/s),retraction speed(30-90 mm/s),and retraction length(0.4-1.2 mm),were systematically adjusted using calibration models.The final optimized parameters(245℃,7 mm^(3)/s,90 mm/s,and 1.2 mm)reduced production time by 43%while preserving structural integrity.American Society for Testing and Materials(ASTM)international standard drop tests confirmed the case’s exceptional impact resistance,demonstrating a 90%reduction in ampoule breakage compared to polylactic acid plus.Further refinements,guided by feedback from 25 emergency professionals,resulted in medicationspecific color coding and an enhanced locking mechanism for usability in high-pressure situations.The final SafeAmpCase model withstood 18 consecutive drop trials without ampoule breakage,confirming its robustness in field conditions.This research underscores the transformative potential of additive manufacturing in developing customized,high-performance solutions for critical healthcare applications,setting a new benchmark for biomedical device design and rapid prototyping.
文摘BACKGROUND Type 1 diabetes mellitus(T1DM)is an autoimmune disease with a multifactorial pathogenesis.Viral infections have been proposed as contributing triggers,supported by the disease’s seasonal pattern,which typically shows higher incidence in autumn and winter.The coronavirus disease 2019(COVID-19)pandemic and associated lockdowns created a unique context to examine the incidence and seasonality of T1DM during a period characterized by reduced circulation of common viral infections.AIM To investigate the incidence and seasonality of T1DM before and during COVID-19 pandemic in relation to global viral infection rates.METHODS This population-based retrospective study utilized a nationwide computerized database.Extracted data included the number of new T1DM cases over the 8 years preceding and during the COVID-19 pandemic,demographic characteristics of affected individuals,and nationwide respiratory virus polymerase chain reaction data from weekly nasal wash sample collections.RESULTS A total of 2176 patients were diagnosed with new-onset T1DM during the prepandemic period,compared to 348 cases during the pandemic.In the same periods,33727 respiratory virus-positive polymerase chain reaction results from nasal wash samples were recorded pre-pandemic,compared to 2603 during the pandemic.Additionally,363399 positive COVID-19 cases were reported during the pandemic period.Seasonality analysis revealed a higher rate of new-onset T1DM cases and a weaker seasonal pattern during the pandemic.Trend analysis showed a consistent increase in T1DM incidence prior to COVID-19,with a more variable trend observed during the pandemic.Correlation analysis between T1DM incidence and respiratory viruses demonstrated a weak correlation between T1DM incidence and a few respiratory viruses.CONCLUSION The observed increase in new-onset T1DM cases and the disruption of its typical seasonal pattern during the COVID-19 pandemic suggest a potential association between respiratory virus exposure and the development of T1DM.
文摘Spermatogenesis is a complex process regulated by endocrine and testicular paracrine/autocrine factors. Gonadotropins are involved in the regulation of several testicular paracrine factors, mainly of the IL-1 family and testicular hormones. Testicular cytokines and growth factors (such as IL-1, IL-6, TNF, IFN-γ, LIF and SCF) were shown to affect both the germ cell proliferation and the Leydig and Sertoli cells functions and secretion. Cytokines and growth factors are produced by immune cells and in the interstitial and seminiferous tubular compartments by various testicular cells, including Sertoli, Leydig, peritubular cells, spermatogonia, differentiated spermatogonia and even spermatozoa. Corresponding cytokine and growth factor receptors were demonstrated on some of the testicular cells. These cytokines also control the secretion of the gonadotropins and testosterone in the testis. Under pathological conditions the levels of pro-inflammatory cytokines are increased and negatively affected spermatogenesis. Thus, the expression levels and the mechanisms involved in the regulation of testicular paracrine/autocrine factors should be considered in future therapeutic strategies for male infertility.
文摘Establishment of an in vitro system that allows the development of testicular germ cells to sperm will be valuable for studies of spermatogenesis and future treatments for male infertility. In the present study, we developed in vitro culture conditions using three-dimensional agar culture system (SACS), which has the capacity to induce testicular germ cells to reach the final stages of spermatogenesis, including spermatozoa generation. Seminiferous tubules from testes of 7-day-old mice were enzymatically dissociated, and intratubular cells were cultured in the upper layer of the SACS in RPMI medium supplemented with fetal calf serum (FCS). The lower layer of the SACS contained only RPMI medium supplemented with FCS. Colonies in the upper layer were isolated after 14 and 28 days of culture and were classified according to their size. Immunofluorescence and real-time PCR were used to analyse specific markers expressed in undifferentiated and differentiated spermatogonia (Vasa, Dazl, OCT-4, C-Kit, GFR- a-l, CD9 and a-6-integrin), meiotic cells (LDH, Crem-1 and Boule) and post-meiotic cells (Protamine-1, Acrosin and SP-IO). Our results reveal that it is possible to induce mouse testicular pre-meiotic germ cell expansion and induce their differentiation to spermatozoa in SACS. The spermatozoa showed normal morphology and contained acrosomes. Thus, our results demonstrate that SACS could be used as a novel in vitro system for the maturation of pre-meiotic mouse germ cells to post-meiotic stages and morphologically-normal spermatozoa.
基金Project supported by PAZY Foundation,Israel(244)
文摘Two types of cyanobacteria of the genus Arthrospira(commonly known as Spirulina) were tested for biosorption of cerium(III) ions from aqueous solutions. An endemic type(ES) found in the northern Negev desert, Israel, and a commercial powder(CS) were used in this study. Biosorption was evaluated as a function of p H, contact time, initial metal concentration, number of sorption-desorption cycles, and salt concentration. The optimum p H range for biosorption was found to be 5.0–5.5. The kinetic characteristics of both Spirulina types were found to be highly compatible with a pseudo-second order kinetic model. The adsorption isotherms of both types were found to be well-suited to Langmuir and Freundlich adsorption isotherms. Maximum biosorption uptakes, according to the Langmuir model, were 18.1 and 38.2 mg/g, for ES and CS, respectively. Sodium chloride concentrations of up to 5 g/L had a minor effect on cerium biosorption. Desorption efficiency was found to be greater than 97% with 0.1 mol/L HNO_3 after three sorption-desorption cycles, without significant loss in the biosorption capacity. The results indicated the feasibility of cerium recovery from industrial wastes using Spirulina biomass.
文摘Explosive Reactive Armor was originally modeled under the assumption that the plates in the cassettes were very thin.Hence their thickness could be ignored,and the thicknesses of the plates were considered only based on their areal mass density.In particular,it was assumed that the jet-plate interaction was controlled by the plates to jet-mass-flux ratio criteria for a specific jet velocity and diameter.In the present study,we extended this analysis,examining the effect of the variation of the mass-flux along the jet on the disruption effect by the two plates.In addition,we examined the thickness effect of the plates on the plate's effectiveness,replacing the steel plates by low-density materials like aluminum and polycarbonate.The mass-flux model was adjusted to account for the plate-thickness effect.It was found that increasing the thickness of the plate,keeping the areal weight unchanged,slightly increases the overall effectiveness of the cassette,in particular by the forward moving plate interacting with the center and the slow parts of the jet.
文摘In vitro culture of spermatogonial stem cells (SSCs) has generally been performed using two-dimensional (2D) culture systems; however, such cultures have not led to the development of complete spermatogenesis. It seems that 2D systems do not replicate optimal conditions of the seminiferous tubules (including those generated by the SSC niche) and necessary for spermatogenesis. Recently, one of our laboratories has been able to induce proliferation and differentiation of mouse testicular germ cells to meiotic and postmeiotic stages including generation of sperm in a 3D soft agar culture system (SACS) and a 3D methylcellulose culture system (MCS). It was suggested that SACS and MCS form a special 3D microenvironment that mimics germ cell niche formation in the seminiferous tubules, and thus permits mouse spermatogenesis in vitro. In this review, we (1) provide a brief overview of the differences in spermatogenesis in rodents and primates, (2) summarize data related to attempts to generate sperm in vitro, (3) report for the first time formation of colonies/clusters of cells and differentiation of meiotic (expression of CREM-1) and postmeiotic (expression of acrosin) germ cells from undifferentiated spermatogonia isolated from the testis of prepubertal rhesus monkeys and cultured in SACS and MCS, and (4) indicate research needed to optimize 3D systems for in vitro primate spermatogenesis and for possible future application to man.
文摘An initiation study is presented in which we examine the effect of the normal and the tangential velocity components of a fragment that impacts a covered and a bare Comp-B explosive. The study is based on calibrated numerical Lagrangian simulations using the LS-Dyna hydrocode. A special procedure was developed to present the estimated initiation point and the shock wave transition into detonation for various impact angles. The influence of the fragment strength and the steel cover thickness on the detonation threshold were also examined. The velocity threshold results are presented and used to modify the Jacobs-Roslund initiation model.
文摘The paper deals with the problem of the distribution of the medicine (enzyme) in the damaged biological tissue where the reaction enzyme—substrat takes place. The biological problem is reduced to a singular degenerate initial-boundary value problem for two coupled ordinary differential equations. Analytical solution of the singular degenerated IBV-problem was obtained by power series. The solution demonstrates the real situation and found suitable to depict the degeneration of singular system, caused by low concentration of the enzyme.
基金supported by a grant from the Israel Atomic Energy Commission for international collaborations
文摘The effect of radio-frequency (RF) or low-frequency (LF) bias voltage on the for- mation of amorphous hydrogenated carbon (a-C:H) films was studied on silicon substrates with a low methane (CH4) concentration (2-10 vol.%) in CH4+Ar mixtures. The bias substrate was applied either by RF (13.56 MHz) or by LF (150 kHz) power supply. The highest hardness values (~18-22 GPa) with lower hydrogen content in the fihns (~20 at.%) deposited at 10 vol.% CH4, was achieved by using the RF bias, However, the films deposited using the LF bias, under similar RF plasma generation power and CH4 concentration (50 W and 10 vol.%, respectively), displayed lower hardness (~6-12 GPa) with high hydrogen content (~40 at.%). The structures analyzed by Fourier Transform Infrared (FTIR) and Raman scattering measurements provide an indication of trans-polyacetylene structure formation. However, its excessive formation in the films deposited by the LF bias method is consistent with its higher bonded hydrogen concentration and low level of hardness, as compared to the film prepared by the RF bias method. It was found that the effect of RF bias on the film structure and properties is stronger than the effect of the low-frequency (LF) bias under identical radio-frequency (RF) powered electrode and identical PECVD (plasma enhanced chemical vapor deposition) system configuration.
基金This work was financially supported by the National Key R&D Program of China(No.2021YFA1500100)the NSF of China(Grants 21821002,21772222,and 91956112)the S&TCSM of Shanghai(Grants 20XD1425100 and 20JC1417100).
文摘Objective:To investigate the effects of a dry aqueous extract of Notobasis syriaca(N.syriaca)on lipopolysaccharide(LPS)-induced inflammation in rats.Methods:Rats were fed the dried extract[500 mg/(kg·d)]for three consecutive days and then were intraperitoneally injected with LPS(1 mg/kg).Two hours after LPS injection,rats were sacrificed and blood and brain regions were collected.Inflammatory mediators'levels in plasma and homogenates of brain regions were determined by ELISA.Results:Pretreatment with the N.syriaca extract resulted in significant anti-inflammatory effects(P<0.05),including:(i)attenuated LPS-induced hypothermia;(ii)decreased hypothalamus and hippocampus prostaglandin E_(2)levels in the LPStreated rats;and,(iii)reduced hypothalamus and hippocampus interleukin-6 and tumor necrosis factor-a levels in the LPS-treated rats.Conclusions:These results suggest that N.syriaca possesses anti-inflammatory properties.Thus,it is possible that long-term consumption of this plant may result in beneficial pharmacological effects.
文摘AIM: To investigate the prevalence and clinical characteristics of Helicobacter pylori(H.pylori)-infected dyspeptic patients with selective immunoglobulin E deficiency(IgE d).METHODS: All individuals who underwent serum totalimmunoglobulin E(Ig E) measurement at the Leumit Healthcare Services(Israel) in 2012 were identified in an electronic database search(n = 18487).From these,selected case group subjects were ≥ 12 years of age and had serum total Ig E < 2 k IU/L(n = 158).The control group was selected from a random sampling of the remaining subjects ≥ 12 years of age to obtain a case-control ratio of 1:20(n = 3160).Dyspeptic diseases,diagnosed no more than 5 years before serum total Ig E testing,were identified and retrieved from the electronic database using specific International Classification of Diseases diagnostic codes.Results of C13-urea breath tests were used to identify subjects infected with H.pylori.Categorical variables between case and control subjects were analyzed using Fisher's exact tests,whereas continuous variables were analyzed using χ2 tests.RESULTS: Dyspepsia was present in 27.2%(43/158) of case subjects and 22.7%(718/3160) of controls.Of these,significantly more case subjects(32/43,74.4%) than controls(223/718,31.1%) were positive for H.pylori(P < 0.01).Esophagogastroduodenoscopy was performed in 19 case and 94 control subjects,revealing that gastritis was more prevalent in IgE d case subjects than in controls(57.9% vs 29.8%,P < 0.05).Furthermore,a significantly greater proportion of case subjects presented with peptic duodenal ulcers(63.2% vs 15.9%,P < 0.01).Histopathologic examination showed marked chronic inflammation,lymphoid follicle formation and prominent germinal centers,with polymorphonuclear cell infiltration of gastric glands,that was similar in case and control biopsy tissues.Finally,Ig Ed case subjects that underwent esophagogastroduodenoscopy were more likely to exhibit treatment-refractory H.pylori infections that require second-line triple antibiotic therapy(47.4% vs 11.7%,P < 0.01).CONCLUSION: IgE d is associated with higher rates ofH.pylori-associated gastritis and peptic duodenal ulcers.
文摘Spindle-cell lipoma (SCL) is a variant of lipoma, usually presenting in the neck or trunk. SCL of the oral cavity is rare. Some cases of oral SCL have been reported;however, the clinico-pathologic characteristics of oral SCL are still unknown. Here we report on 2 cases and review 33 cases of oral SCL published in the literature. The patients were 23 men and 12 women, with a mean age of 55 years (range 23 - 88 years);there were no children. Tumor sites included: tongue (n = 13), cheek/buccal mucosa (n = 11), floor of mouth (n = 5), lip (n = 2), hard palate (n = 2), alveolar ridge (n = 1), and maxilla (n = 1). The mean tumor size was 20.87 mm (range 3 - 50 mm), smaller than extra-oral lesions. Thirty-three patients (94%) presented with a single lesion that was circumscribed and composed of mature adipocytes admixed with bland spindle cells. The spindle cells were strongly immunoreactive for CD34, whereas the adipocytes were negative. The main differential diagnosis is atypical lipoma/well-differentiated liposarcoma. All lesions underwent local excision and recurrences are rare. Oral SCL do not seem to differ from their extra-oral counterpart, which are much more common and larger in size. SCL should be included in the differential diagnosis of oral cavity mesenchymal tumors.
文摘Background: Epstein Barr Virus (EBV) is associated with different kinds of tumors. In the present study we tried to understand its role in pediatric MDS of a 4-year-old girl with EBV infection and MDS with refractory anemia and monosomy 7. Procedures: The work-up included: hematological tests;serology for IgM, IgG antibodies to EBV;PCR for EBV;cytogenetics of bone marrow (BM), and FISH analysis of BM and blood;immunohistochemistry-LMP1 expression on BM smears. Results: Hematological follow up showed constant mild dysplastic changes mostly in the erythroid lineage. PCR for EBV showed positive results in the nasopharygeal smears as well as in blood 15 weeks after disease onset. Cytogenetic analysis showed monosomy7 inall the mitoses of BM sample. Fluorescence in situ hybridization (FISH) showed monosomy 7% in 57% of the cells, followed by a decreased tendency in the percentage of monosomy 7 cells in both BM and blood. Immunohistochemistry for EBV-latent membrane protein 1 (LMP-1) on the patient’s BM smears, 21 weeks post disease onset, showed 9% positive cells, 80% of them carried monosomy 7. Conclusion: The parallel occurrence of the EBV infection and MDS, as well as the continuous EBV PCR positive and monosomy 7, support the possibility that they are related.
文摘In assessing the relationship between calcium supplementation and maintaining bone mass or reducing the risk of fracture, the effectiveness of calcium supplementation has never been decisive. Freshwater crayfish rely on amorphous calcium carbonate (ACC), an instable polymorph of calcium carbonate, as the main mineral in the exoskeleton and in the temporary storage organ, the gastrolith. Inspired by the crayfish model, we have previously shown an increase in calcium bioavailability in rats administered with synthetic stable ACC vs. crystalline calcium carbonate (CCC). The current study compared the effects of amorphous calcium derived from either gastrolith or synthetic ACC with those of crystalline calcium, found in commercial CCC or calciumcitrate supplements, in a bone loss prevention model. Rats were subjected to either sham or ovariectomy (OVX) operation (n^20/ group) followed by administration of food pellets supplemented with 0.5% calcium from either source over 12 weeks. Micro-computed tomography (μCT) and histomorphometric analyses revealed bone loss prevention by both gastrolith and ACC treatments, manifested by an increase in morphometric bone parameters, compared to both CCC-?and calcium citrate-treated groups. Both gastrolith and ACC treatments resulted in bone formation in the tibia cancellous bone, indicated by dynamic histomorphometry parameters, compared to either the CCC or calcium citrate treatments. Levels of urine deoxypyridinoline (DPD), suggested an anti-resorptive effect of ACC, which was also the only treatment that led to a significant increase in vertebral mechanical strength, as supported by μCT analysis of topology and orientation parameters of the vertebral trabeculae. To our knowledge, such levels of bone loss prevention by calcium supplements have never been reported. These findings thus suggest the potential of both natural (crayfish gastrolith) and, to a greater extent, synthetic ACC sources for the prevention of metabolic bone disorders and possibly of osteoporotic processes.
文摘Purpose: Cylindrical ionization chambers as the PinPoint and the CC01 have high-spatial resolution and cylindrical symmetry in relevance to small fields. Dosimetry of newly advanced technologies that include non-coplanar beams, such as in Gamma-Knife, VMAT and IMRT treatment plans, the angular dependence of the ion chamber is essential. Therefore in this study we simulated two common used ion chambers using a Monte Carlo method. Methods: The angular dependence for the CC01 and the PinPoint were calculated for a vast angular range in a cylindrical water phantom for two LINAC photon beams, 6 MV and 15 MV. The calculations were performed for fully structural description of each ion chamber using Monte Carlo code, in order to reveal unsymmetrical response dose higher than 2% in medical applications. The calculated dose response, for the CC01 ion chamber, was validated with measurements. Results: The CC01 ion chamber showed a very small angular dependence compared to the PinPoint ion chamber. The relative angular dependence amplitude of the PinPoint was about 12% in the range of 0° - 110°. Conclusions: The differences in the ion chambers structure led to the variations in the relative angular dependence amplitude. Therefore, when choosing a detector, not only the volume of the ionization chamber but also its structure must be taken into consideration.
基金supported by the National Natural Science Foundation of China(Nos. 21875216, 21734008, 21474088, 51473142, 51561145001, 51620105006, 61721005)Zhejiang Province Science and Technology Plan(No.2018C01047)Research Grant Council of Hong Kong(General Research Fund No. 14314216, CUHK Direct Grant No. 4053227)
文摘Poly(3-hexylthiophene)(P3HT) is a low-cost polymer donor for organic solar cells (OSCs). However, the P3HT-based OSCs usually give low power conversion efficiencies (PCEs) due to the wide bandgap and the high-lying energy levels of P3HT. To solve this problem, in this work, we design and synthesize a new A-D-A type non-fullerene acceptor, DFPCBR, which owns an electron-donating (D) core constructed by linking a 2,5-difluorobenzene ring with two cyclopentadithiophene moieties, and two electron-accepting (A) end-groups of benzo[c][1,2,5]thiadiazole connected with 3-ethyl-2-thioxothiazolidin-4-one. Because of the strong electron-donating ability and large conjugation effect of D core, DFPCBR shows appropriate energy levels and a narrow bandgap matching well with those of P3HT. Therefore, with P3HT as the donor and DFPCBR as the acceptor, the OSCs possess broad absorption range from 350 nm to 780 nm and the reduced energy loss (Eloss) of 0.79 eV (compared with ~1.40 eV for the P3HT:PC61BM device), providing a good PCE of 5.34% with a high open-circuit voltage (VOC) of 0.80 V. Besides, we observe that the photovoltaic performances of these devices are insensitive to the thickness of the active layers:even if the active layer is as thick as 320 nm,~80%of the best PCE is maintained, which is rarely reported for fullerene-free P3HT-based OSCs, suggesting that DFPCBR has the potential application in commercial OSCs in the future.