scholarly journals Regeneration indicators of Detarium microcarpum Guill. & Perl. in the Mbe plain of the Adamawa, Cameroon

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Georges Maxime LAMY LAMY
Keyword(s):  
Population Distribution ◽  
Tree Height ◽  
Site Specific ◽  
Floristic Inventory ◽  
Detarium Microcarpum ◽  
Significant Difference ◽  
Piliostigma Thonningii ◽  
Large Living ◽  
Over Exploitation

Background In Africa, the Detarium microcarpum Guill. & Perr. species is extremely important culturally, ecologically and socio-economically. This importance has led to its over-exploitation leading to an in situ rarity of its individuals. As a consequence, a conservation alert is increasingly reported across the continent due to the risk of extinction of this multipurpose plant. Unfortunately, indicators of regeneration and conservation guidelines for this species have been not developped yet. The objective was to evaluate the habitat, population distribution, dendrometric characteristics and structure of the plant which are indicators of regeneration in Cameroon.    Methodology A floristic inventory as well as the vegetation transect method was used in the villages Def, Karna Manga and Karna Petel located in Adamawa, Cameroon. Results A total of 109 individuals of the plant were counted with a density of 3.5 individuals per hectare. No plant individuals regenerated in human-controlled habitats (bush fields and home gardens). Population distribution, companion species (Bombax costatum, Piliostigma thonningii and Terminalia macroptera) more recurrent, species of the family Caesalpiniaceae in majority, dendrometric characteristics with a significant difference (P ˂ 0.05) between sites, horizontal and vertical structures although all significant at Karna Manga, showed site-specific patterns. Conclusion The regeneration indicators (habitat, population distribution, structure and dendrometric characteristics: crown diameter, diameter at breast height, height of the first large living branch and tree height) showed that conservation in situ requires accounting for local, site-specific conditions. For the continuation, the less expensive domestication techniques specific to the plant are recommended. 

To Eliminate Curtain Effect of FIB TEM Samples by a Combination of Sample Dicing and Backside Milling

2014 ◽  
Author(s):  
Jian-Shing Luo ◽  
Hsiu Ting Lee
Keyword(s):  
Sample Preparation ◽  
Focused Ion Beam ◽  
Preparation Method ◽  
Low Cost ◽  
Ion Beam ◽  
Sample Preparation Method ◽  
Site Specific ◽  
Dual Beam ◽  
Transmission Electron

Abstract Several methods are used to invert samples 180 deg in a dual beam focused ion beam (FIB) system for backside milling by a specific in-situ lift out system or stages. However, most of those methods occupied too much time on FIB systems or requires a specific in-situ lift out system. This paper provides a novel transmission electron microscopy (TEM) sample preparation method to eliminate the curtain effect completely by a combination of backside milling and sample dicing with low cost and less FIB time. The procedures of the TEM pre-thinned sample preparation method using a combination of sample dicing and backside milling are described step by step. From the analysis results, the method has applied successfully to eliminate the curtain effect of dual beam FIB TEM samples for both random and site specific addresses.

Increse of newly - detected in situ cancers in non-palpable breast lesions

2006 ◽  
Vol 53 (1) ◽  
pp. 73-75
Author(s):  
N. Miletic ◽  
D. Stojiljkovic ◽  
M. Inic ◽  
M. Prekajski ◽  
A. Celebic ◽  
...  
Keyword(s):  
Breast Tissue ◽  
Malignant Disease ◽  
Clinical Stage ◽  
Diagnostic Procedures ◽  
Basal Membrane ◽  
Needle Aspiration ◽  
Screening Mammography ◽  
Significant Difference ◽  
Malignant Lesions

Great importance in detecting cancer in the phase of in situ lays in the fact that the epithelial layer is deprived of blood and lymph vessels, so metastases may develop only when basal membrane has been broken. This paper includes 46 operated women in whom it preoperatively had been verified suspect non-palpable lesion. The preoperative diagnostics included use of high- resolution mammography, aimed mammography, palpatory examination, as well as fine-needle aspiration (FNA), biopsy and cytologic analysis of the sample. The methodology of this work implies the use of stereotaxic marking, specimen mammography and ex-tempore pathohistology analysis. Out of 46 investigated patients in clinical stage T0N0M0, in whom there were no signs of malignant disease, and according to suspect lesion of initial screening mammography, malignant lesions of breast tissue were diagnosed in 19 patients (41%) intraoperatively. Three of these lesions (15,8%) were histopathologically verified as in situ. Comparing our results with data of the Institute of oncology and radiology of Serbia hospital registry (IORS) for the year 2001, from 1173 patients registered with malignant lesions, only 16 ones (1,4%) had in situ cancer, operated on the basis of the suspect mammography of clinical stage T0N0M0. Statistically significant difference was found related to the number of detected cancers in this early phase of the breast malignant disease. This limits surgical intervention to tumorectomy, with preservation of the remaining breast tissue, what brings to healing, justifying in that way, screening examinations and routine application of the most contemporary diagnostic procedures.

scholarly journals Effects of habitat edges on vegetation structure and the vulnerable golden-brown mouse lemur (Microcebus ravelobensis) in northwestern Madagascar

BMC Ecology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Bertrand Andriatsitohaina ◽  
Daniel Romero-Mujalli ◽  
Malcolm S. Ramsay ◽  
Frederik Kiene ◽  
Solofonirina Rasoloharijaona ◽  
...  
Keyword(s):  
Body Mass ◽  
Edge Effects ◽  
Vegetation Structure ◽  
Species Abundance ◽  
Tree Height ◽  
Logistic Function ◽  
Study Region ◽  
Large Trees ◽  
Significant Difference ◽  
Vegetation Parameters

Abstract Background Edge effects can influence species composition and community structure as a result of changes in microenvironment and edaphic variables. We investigated effects of habitat edges on vegetation structure, abundance and body mass of one vulnerable Microcebus species in northwestern Madagascar. We trapped mouse lemurs along four 1000-m transects (total of 2424 trap nights) that ran perpendicular to the forest edge. We installed 16 pairs of 20 m2 vegetation plots along each transect and measured nine vegetation parameters. To determine the responses of the vegetation and animals to an increasing distance to the edge, we tested the fit of four alternative mathematical functions (linear, power, logistic and unimodal) to the data and derived the depth of edge influence (DEI) for all parameters. Results Logistic and unimodal functions best explained edge responses of vegetation parameters, and the logistic function performed best for abundance and body mass of M. ravelobensis. The DEI varied between 50 m (no. of seedlings, no. of liana, dbh of large trees [dbh ≥ 10 cm]) and 460 m (tree height of large trees) for the vegetation parameters, whereas it was 340 m for M. ravelobensis abundance and 390 m for body mass, corresponding best to the DEI of small tree [dbh < 10 cm] density (360 m). Small trees were significantly taller and the density of seedlings was higher in the interior than in the edge habitat. However, there was no significant difference in M. ravelobensis abundance and body mass between interior and edge habitats, suggesting that M. ravelobensis did not show a strong edge response in the study region. Finally, regression analyses revealed three negative (species abundance and three vegetation parameters) and two positive relationships (body mass and two vegetation parameters), suggesting an impact of vegetation structure on M. ravelobensis which may be partly independent of edge effects. Conclusions A comparison of our results with previous findings reveals that edge effects are variable in space in a small nocturnal primate from Madagascar. Such an ecological plasticity could be extremely relevant for mitigating species responses to habitat loss and anthropogenic disturbances.

scholarly journals SMILE and Wavefront-Guided LASIK Out-Compete Other Refractive Surgeries in Ameliorating the Induction of High-Order Aberrations in Anterior Corneal Surface

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Min-jie Ye ◽  
Cai-yuan Liu ◽  
Rong-feng Liao ◽  
Zheng-yu Gu ◽  
Bing-ying Zhao ◽  
...  
Keyword(s):  
Spherical Aberration ◽  
Laser In Situ Keratomileusis ◽  
Small Incision Lenticule Extraction ◽  
Corneal Surface ◽  
Small Incision ◽  
Significant Difference ◽  
Lenticule Extraction ◽  
A Prospective Study ◽  
High Order Aberrations

Purpose. To compare the change of anterior corneal higher-order aberrations (HOAs) after laser in situ keratomileusis (LASIK), wavefront-guided LASIK with iris registration (WF-LASIK), femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK), and small incision lenticule extraction (SMILE).Methods. In a prospective study, 82 eyes underwent LASIK, 119 eyes underwent WF-LASIK, 88 eyes underwent FS-LASIK, and 170 eyes underwent SMILE surgery. HOAs were measured with Pentacam device preoperatively and 6 months after surgery. The aberrations were described as Zernike polynomials, and analysis focused on total HOAs, spherical aberration (SA), horizontal coma, and vertical coma over 6 mm diameter central corneal zone.Results. Six months postoperatively, all procedures result in increase of anterior corneal total HOAs and SA. There were no significant differences in the induced HOAs between LASIK and FS-LASIK, while SMILE induced fewer total HOAs and SA compared with LASIK and FS-LASIK. Similarly, WF-LASIK also induced less total HOAs than LASIK and FS-LASIK, but only fewer SA than FS-LASIK (P<0.05). No significant difference could be detected in the induced total HOAs and SA between SMILE and WF-LASIK, whereas SMILE induced more horizontal coma and vertical coma compared with WF-LASIK (P<0.05).Conclusion. FS-LASIK and LASIK induced comparable anterior corneal HOAs. Compared to LASIK and FS-LASIK, both SMILE and WF-LASIK showed advantages in inducing less total HOAs. In addition, SMILE also possesses better ability to reduce the induction of SA in comparison with LASIK and FS-LASIK. However, SMILE induced more horizontal coma and vertical coma compared with WF-LASIK, indicating that the centration of SMILE procedure is probably less precise than WF-LASIK.

Molecular modulation of calcium oxalate crystallization

2006 ◽  
Vol 291 (6) ◽  
pp. F1123-F1132 ◽  
Author(s):  
James J. De Yoreo ◽  
S. Roger Qiu ◽  
John R. Hoyer
Keyword(s):  
Molecular Modeling ◽  
Calcium Oxalate ◽  
Stone Formation ◽  
Energy Levels ◽  
Critical Role ◽  
Specific Interactions ◽  
Crystal Surfaces ◽  
Site Specific

Calcium oxalate monohydrate (COM) is the primary constituent of the majority of renal stones. Osteopontin (OPN), an aspartic acid-rich urinary protein, and citrate, a much smaller molecule, are potent inhibitors of COM crystallization at levels present in normal urine. Current concepts of the role of site-specific interactions in crystallization derived from studies of biomineralization are reviewed to provide a context for understanding modulation of COM growth at a molecular level. Results from in situ atomic force microscopy (AFM) analyses of the effects of citrate and OPN on growth verified the critical role of site-specific interactions between these growth modulators and individual steps on COM crystal surfaces. Molecular modeling investigations of interactions of citrate with steps and faces on COM crystal surfaces provided links between the stereochemistry of interaction and the binding energy levels that underlie mechanisms of growth modification and changes in overall crystal morphology. The combination of in situ AFM and molecular modeling provides new knowledge that will aid rationale design of therapeutic agents for inhibition of stone formation.

Verification of In Situ Thresholds and Integrated Real-Ear Measurements

2010 ◽  
Vol 21 (10) ◽  
pp. 663-670 ◽  
Author(s):  
Jeffrey J. DiGiovanni ◽  
Ryan M. Pratt
Keyword(s):  
Measurement System ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Normal Hearing ◽  
Analysis Tool ◽  
Ohio University ◽  
Positive Direction ◽  
Significant Difference ◽  
Threshold Measurement

Background: Accurate prescriptive gain results in a more accurate fit, lower return rate in hearing aids, and increased patient satisfaction. In situ threshold measurements can be used to determine required gain. The Widex Corporation uses an in situ threshold measurement strategy, called the Sensogram. Real-ear measurements determine if prescriptive gain targets have been achieved. Starkey Laboratories introduced an integrated real-ear measurement system in their hearing aids. Purpose: To determine whether the responses obtained using the Widex Sensogram were equivalent to those obtained using current clinical threshold measurement methods. To determine the accuracy of the Starkey IREMS™ (Integrated Real Ear Measurement System) in measuring RECD (real-ear to coupler difference) values compared to a dedicated real-ear measurement system. Research Design: A verification design was employed by comparing participant data measured from standard, benchmark equipment and procedures against new techniques offered by hearing-aid manufacturers. Study Sample: A total of 20 participants participated in this study. Ten participants with sensorineural hearing loss were recruited from the Ohio University Hearing, Speech, and Language Clinic participated in the first experiment. Ten participants with normal hearing were recruited from the student population at Ohio University participated in both experiments. The normal-hearing group had thresholds of 15 dB HL or better at the octave frequencies of 250–8000 Hz. The hearing-impaired group had thresholds of varying degrees and configurations with thresholds equal to or poorer than 25 dB HL three-frequency pure-tone average. Data Collection and Analysis: The order of measurement method for both experiments was counterbalanced. In Experiment 1, thresholds obtained via the Widex Sensogram were compared to thresholds obtained for each participant using a clinical audiometer and ER-3A insert ear phones. In Experiment 2, RECD values obtained via the Starkey IREMS were compared to RECD values obtained via the Audioscan Verifit™. A repeated-measures analysis of variance (ANOVA) was used for statistical analysis, and a Fisher's LSD (least significant difference) was used as a post hoc analysis tool. Results: A significant difference between Sensogram thresholds and conventional audiometric thresholds was found with the Sensogram method resulting in better threshold values at 0.5, 1.0, and 2.0 kHz for both groups. In Experiment 2, a significant difference between RECD values obtained by the Starkey IREMS and the Audioscan Verifit system was found with significant differences in RECD values found at 0.25, 0.5, 0.75, 1.5, 2.0, and 6.0 kHz. Conclusions: The Sensogram data differ significantly from traditional audiometry at several frequencies important for speech intelligibility. Real-ear measures are still required for verification of prescribed gain, however, calling into question any claims of shortened fitting time. The Starkey IREMS does perform real-ear measurements that vary significantly from benchmark equipment. These technologies represent a positive direction in prescribing accurate gain during hearing-aid fittings, but a stand-alone system is still the preferred method for real-ear measurements in hearing-aid fittings.

Temporal distribution and population structure of two congeneric species ofCucullanus(Nematoda: Cucullanidae) inOrthopristis ruberin Venezuela

2008 ◽  
Vol 82 (1) ◽  
pp. 69-76 ◽  
Author(s):  
A.K. Bashirullah ◽  
M.T. Diaz
Keyword(s):  
Temporal Distribution ◽  
Caribbean Sea ◽  
Congeneric Species ◽  
Mean Intensity ◽  
Qualitative And Quantitative ◽  
The North ◽  
Significant Difference ◽  
The Caribbean ◽  
Over Exploitation ◽  
Fish Hosts

AbstractThe qualitative and quantitative parameters of temporal distribution ofCucullanus tripapillatusandCucullanus chrysophrydesin the intestine ofOrthopristis ruberin the Caribbean Sea on the north of Margarita Island, Venezuela were analysed. A total of 540 fish were collected at random from the catch of commercial trawlers during 1982–83 and 1992–93. Both species ofCucullanuswere found throughout the year; prevalence and mean intensity ofC. tripapillatuswere higher than that ofC. chrysophrydes. A significant difference was found in infection between the two years of sampling. Female worms were more abundant than male in both years. Both species exhibited pronounced prevalence and maturity in September and March of each year, indicating seasonality. The patterns of occurrence of the two species ofCucullanusinO. ruberdid not change in the 10-year interval but the host size and number of parasites declined, which may be due to over-exploitation of definitive fish hosts.

scholarly journals In situ acoustic analysis of two twentieth-century heritage carillons

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Scott Allan Orr
Keyword(s):  
Twentieth Century ◽  
Acoustic Analysis ◽  
Mechanical Action ◽  
Ex Situ ◽  
Physical Acoustics ◽  
Acoustic Characteristics ◽  
Dynamic Level ◽  
Significant Difference ◽  
And Function

AbstractCarillons are a diverse and global form of musical and civic heritage: musical instruments comprised of a series of 23 or more bells, typically hung in a tower-like structure, tuned chromatically and played from a touch-sensitive manual and pedal console using an elaborate mechanical action. Carillon bells have a distinct series of musical overtones which should be accurately tuned to one another and with other bells they sound alongside. Although these overtones have been previously studied ex situ, this study assesses the acoustic characteristics of two early-twentieth century carillons in Toronto, Canada as a combination of structure, bells, and mechanical action. Thus, the instrument and its context are considered holistically, more accurately reflecting the musical sensitivity of a carillonist. Spectral analysis of audio samples of each bell at different musical dynamic levels enabled the analysis of the acoustic qualities of the bells and the mechanical action of the instruments. The tuning of bells in the instruments varied; most importantly, there was a significant difference between the audial intensity of the bell tones produced by the instruments, demonstrating the importance of the mechanical action as part of the ‘carillon system’. This was represented with a resistive power-law model, that represents the sensitivity of intensity to carillonist musical dynamic level. A discussion of the implications for artistic and heritage practice follows. Understanding the in situ physical acoustics of the carillon as a holistic instrument in its context informs performers, arrangers, and composers of how they can best embrace the instrument’s unique qualities to improve artistic pursuits and support the appreciation of carillons as heritage instruments and function as civic voices.

Molecular Cytogenetic Classification of Down Syndrome and Screening of Somatic Aneuploidy in Mothers

2021 ◽  
pp. 1-9
Author(s):  
Sushil Kumar Jaiswal ◽  
Ashok Kumar ◽  
Amit Kumar Rai
Keyword(s):  
Down Syndrome ◽  
Peripheral Blood ◽  
Trisomy 21 ◽  
Health Management ◽  
Chromosome 21 ◽  
Robertsonian Translocations ◽  
Significant Difference ◽  
And Control

Down Syndrome (DS) caused by trisomy 21 results in various congenital and developmental complications in children. It is crucial to cytogenetically diagnose the DS cases early for their proper health management and to reduce the risk of further DS childbirths in mothers. In this study, we performed a cytogenetic analysis of 436 suspected DS cases using karyotyping and fluorescent in situ hybridization. We detected free trisomies (95.3%), robertsonian translocations (2.4%), isochromosomes (0.6%), and mosaics (1.2%). We observed a slightly higher incidence of DS childbirth in younger mothers compared to mothers with advanced age. We compared the somatic aneuploidy in peripheral blood of mothers having DS children (MDS) and control mothers (CM) to identify biomarkers for predicting the risk for DS childbirths. No significant difference was observed. After induced demethylation in peripheral blood cells, we did not observe a significant difference in the frequency of aneuploidy between MDS and CM. In conclusion, free trisomy 21 is the most common type of chromosomal abnormality in DS. A small number of DS cases have translocations and mosaicism of chromosome 21. Additionally, somatic aneuploidy in the peripheral blood from the mother is not an effective marker to predict DS childbirths.

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