Background: Complications after endoscopic retrieval of kidney and ureter stones are obviously related to the size of the stones as well as the experience of the surgeon and other factors. During the procedure it is s...Background: Complications after endoscopic retrieval of kidney and ureter stones are obviously related to the size of the stones as well as the experience of the surgeon and other factors. During the procedure it is sometimes difficult for surgeons to estimate stone size and therefore give prognostic advises. The visual perception of the stone size depends on the shape, colour, distance to the renoscope and dilatation of the ureter. This is the so-called binding problem, because shape, color and direction of motion are processed separately by different population of optical neurons. In order to establish a better prognostic rational especially for less experienced surgeons, we established an intra operative semi-quantitative measurement of the stone size supported by a stone basket. Materials and Methods: We modified the tipped, nitinol stone baskets from the company Urotech with diameters of 2.5, 3.0 and 4 FR. The handle of this basket has a spring mechanism, which automatically closes the basket and provides a predefined fixation force of the stones within the basket. On the handle we established a non-linear scale in mm by grabbing standardized balls or standardized screws. Result: The scales are nonlinear because of the nonlinear relation between the diameter of the stone and the distance of the slider. Also the scales differ in between the basket size, because of the different strain conditions due to the different wire sizes and materials or the spring and basket. Conclusion: This scale could be an important orientation for a surgeon during endourological procedures to estimate stone sizes. After further clinical experience a semi-quantitative visualization like green, yellow and red colors could help to predict potential complications due to large stone sizes. Finally it could bevery interesting for other disciplines like gastroenterology.展开更多
The present study reports the results of extracorporeal shock-wave lithotripsy treatment for renal and ureteral stones in Duhok city. The data were collected from the center of breakdown kidney stones in Duhok hospita...The present study reports the results of extracorporeal shock-wave lithotripsy treatment for renal and ureteral stones in Duhok city. The data were collected from the center of breakdown kidney stones in Duhok hospital. There were a total of 40 patients (25 males and 15 females) aged from 20 to 60 years old. The patients harboring (23 renal and 17 ureteral) stones of size ranged from 7.5 to 20 mm. Almost stones are of average size 9 mm and composed of uric acid, calcium and cystine stones. The study has been carried out by taking into consideration the parameters (type, sizes, composition and location of stone as well as region and ages of patients, also power, number of shock wave and sessions). The results show that the stones size increases according to increasing ages of patients (male and female) for uric acid ureter stone and calcium (renal, ureter) stones. Also (renal, ureter) stone size for patients aged from 20 to 30 years old increases from the minimum value for phosphate to maximum value for cystine stones, while for patients aged from 40 to 60 years old, the minimum size is obtained for calcium oxalate and the maximum size for calcium only. On the other hand, for uric acid stones of average size 9 mm, number of shock wave and sessions as well as the power required to breakdown the stones decrease nearly exponentially according to enhancing patients’ ages. At the same time, it's found that for adult patients (20 - 30 years old), number of sessions and the power of shock wave decrease also according to increasing size of calcium and cystine stones. Contrary to that, for the same ages and renal, uretral cysteine stones number of shock wave needed to breakdown large stones will be increased.展开更多
In the present study, investigation of extracorporeal shock wave lithotripsy in Zakho City for breakdown kidney and ureteral stones has been carried out. The data were collected from the center of breakdown kidney sto...In the present study, investigation of extracorporeal shock wave lithotripsy in Zakho City for breakdown kidney and ureteral stones has been carried out. The data were collected from the center of breakdown kidney stones in Zakho hospital. A total of 34 patients (25 male and 9 female) of ages ranged from 20 - 60 years were treated with ESWL. The patient harboring 24 renal stones and 10 ureteral stones of size ranged from 7 to 23 mm of almost patients are 8 mm and composed of calcium oxalate. The study has been conducted taking in to consideration the parameters (type, sizes, composition and location of stone as well as region and ages of patients, also power, number of shock wave and session). The results show that the number of shock wave decreases nearly exponentially with the ages of patients for calcium oxalate stone of size 8 mm under constant power 4 watt while it tends to increase according to increasing stones size for the patients of ages 20 - 30 years. The size of calcium oxalate stones decreases nearly exponentially with the patients’ ages for workers in Zakho city. Also for same size 8 mm of (calcium, phosphate, and oxalate) stones and different regions of zakho city, the number of shock waves decreases according to increasing ages of patients. Contrary to that for certain size of stones 8 mm, the number of shock wave starts to increase from uric acid to maximum value for calcium oxalate stone for the adult patients of age’s 22 up to 30 years. However for elders ages 30 - 60 years and different regions, the size of renal and ureteric stones increases from the minimum value for calcium, phosphate, oxalate to maximum value for calcium oxalate stone only. Uric acid stone requires minimum power to break, while the calcium oxalate needs maximum power to fragment due to its hardness composition. Later number of session of shock wave required for crushing each stones size increases according to increasing its size while its variation due to enhancing patients ages for calcium oxalate of size 8 mm results in nearly a decreasing exponential behavior.展开更多
Stone matrix asphalt （SMA） is a gap-graded bituminous mixture which can be used in surface layer of high volume pavements. The mixture has higher concen- trations of coarse aggregates, providing strength and rut res...Stone matrix asphalt （SMA） is a gap-graded bituminous mixture which can be used in surface layer of high volume pavements. The mixture has higher concen- trations of coarse aggregates, providing strength and rut resistance to the mixture, and higher asphalt content giving durability. There must be a proper stone-to-stone contact between the coarse aggregates of SMA, and hence aggre- gate gradation is an important factor in this mixture. In the current study, two aggregate gradations, with nominal maximum aggregate sizes （NMAS） 16 and 13 mm were adopted to prepare SMA mixtures and their laboratory performances were compared. Polymer-modified bitumen （PMB） was used as the binder material and no stabilising additive was used, since drain down was within permissible limits for both mixtures with PMB. Conventional cylin- drical specimens were prepared in superpave gyratory compactor with bitumen contents 5.0 %, 5.5 %, 6.0 %, 6.5 % and 7.0 % by weight of aggregates, and volumetric and Marshall properties were determined. Tensile strength, behaviour to repeated loading etc. were checked for cylindrical specimens prepared at optimum bitumen con- tent, whereas specially prepared slab specimens were used to check the rutting resistance of SMA mixtures. From the laboratory study, it was observed that, out of the two SMA mixtures, the one with NMAS 16 mm performed better compared to the other. These improved properties may be attributed towards the larger coarse aggregate sizes in the mixture.展开更多
Egypt is characterized by wide occurrence of serpentinites, particularly in the central and southern parts of Eastern Desert. There are several cooperate factors that affect the serpentinites used as ornamental stones...Egypt is characterized by wide occurrence of serpentinites, particularly in the central and southern parts of Eastern Desert. There are several cooperate factors that affect the serpentinites used as ornamental stones. These factors involve mineralogical characteristics (including mineral composition and microstructure parameter), physical properties and mechanical properties. Antigorite is an essential serpentinite mineral, with a minor amount of chrysotile. Talc, carbonates (magnesite and dolomite) and tremolite are the main associated minerals. Quality and quantity of associated minerals such as talc and carbonates (dolomite and magnesite) affect the properties of serpentinites used as ornamental stones. Carbonates are resistant to weathering but suffer from acidic cleaning agents in interior use, whereas serpentinites with a high content of talc used on external faces undergo an increase in volume and a consequent rapid degradation. Studied serpentinites are characterized by relatively small grain size with foliated texture, low water absorption, low porosity, and high abrasion resistance. In the samples studied the uniaxial compressive strength (UCS) varies between 89 and 189 MPa, with an average of 152 MPa. According to the classification of Bell (1992), sample No. B8 is very high in strength while the rest high in strength.展开更多
文摘Background: Complications after endoscopic retrieval of kidney and ureter stones are obviously related to the size of the stones as well as the experience of the surgeon and other factors. During the procedure it is sometimes difficult for surgeons to estimate stone size and therefore give prognostic advises. The visual perception of the stone size depends on the shape, colour, distance to the renoscope and dilatation of the ureter. This is the so-called binding problem, because shape, color and direction of motion are processed separately by different population of optical neurons. In order to establish a better prognostic rational especially for less experienced surgeons, we established an intra operative semi-quantitative measurement of the stone size supported by a stone basket. Materials and Methods: We modified the tipped, nitinol stone baskets from the company Urotech with diameters of 2.5, 3.0 and 4 FR. The handle of this basket has a spring mechanism, which automatically closes the basket and provides a predefined fixation force of the stones within the basket. On the handle we established a non-linear scale in mm by grabbing standardized balls or standardized screws. Result: The scales are nonlinear because of the nonlinear relation between the diameter of the stone and the distance of the slider. Also the scales differ in between the basket size, because of the different strain conditions due to the different wire sizes and materials or the spring and basket. Conclusion: This scale could be an important orientation for a surgeon during endourological procedures to estimate stone sizes. After further clinical experience a semi-quantitative visualization like green, yellow and red colors could help to predict potential complications due to large stone sizes. Finally it could bevery interesting for other disciplines like gastroenterology.
文摘The present study reports the results of extracorporeal shock-wave lithotripsy treatment for renal and ureteral stones in Duhok city. The data were collected from the center of breakdown kidney stones in Duhok hospital. There were a total of 40 patients (25 males and 15 females) aged from 20 to 60 years old. The patients harboring (23 renal and 17 ureteral) stones of size ranged from 7.5 to 20 mm. Almost stones are of average size 9 mm and composed of uric acid, calcium and cystine stones. The study has been carried out by taking into consideration the parameters (type, sizes, composition and location of stone as well as region and ages of patients, also power, number of shock wave and sessions). The results show that the stones size increases according to increasing ages of patients (male and female) for uric acid ureter stone and calcium (renal, ureter) stones. Also (renal, ureter) stone size for patients aged from 20 to 30 years old increases from the minimum value for phosphate to maximum value for cystine stones, while for patients aged from 40 to 60 years old, the minimum size is obtained for calcium oxalate and the maximum size for calcium only. On the other hand, for uric acid stones of average size 9 mm, number of shock wave and sessions as well as the power required to breakdown the stones decrease nearly exponentially according to enhancing patients’ ages. At the same time, it's found that for adult patients (20 - 30 years old), number of sessions and the power of shock wave decrease also according to increasing size of calcium and cystine stones. Contrary to that, for the same ages and renal, uretral cysteine stones number of shock wave needed to breakdown large stones will be increased.
文摘In the present study, investigation of extracorporeal shock wave lithotripsy in Zakho City for breakdown kidney and ureteral stones has been carried out. The data were collected from the center of breakdown kidney stones in Zakho hospital. A total of 34 patients (25 male and 9 female) of ages ranged from 20 - 60 years were treated with ESWL. The patient harboring 24 renal stones and 10 ureteral stones of size ranged from 7 to 23 mm of almost patients are 8 mm and composed of calcium oxalate. The study has been conducted taking in to consideration the parameters (type, sizes, composition and location of stone as well as region and ages of patients, also power, number of shock wave and session). The results show that the number of shock wave decreases nearly exponentially with the ages of patients for calcium oxalate stone of size 8 mm under constant power 4 watt while it tends to increase according to increasing stones size for the patients of ages 20 - 30 years. The size of calcium oxalate stones decreases nearly exponentially with the patients’ ages for workers in Zakho city. Also for same size 8 mm of (calcium, phosphate, and oxalate) stones and different regions of zakho city, the number of shock waves decreases according to increasing ages of patients. Contrary to that for certain size of stones 8 mm, the number of shock wave starts to increase from uric acid to maximum value for calcium oxalate stone for the adult patients of age’s 22 up to 30 years. However for elders ages 30 - 60 years and different regions, the size of renal and ureteric stones increases from the minimum value for calcium, phosphate, oxalate to maximum value for calcium oxalate stone only. Uric acid stone requires minimum power to break, while the calcium oxalate needs maximum power to fragment due to its hardness composition. Later number of session of shock wave required for crushing each stones size increases according to increasing its size while its variation due to enhancing patients ages for calcium oxalate of size 8 mm results in nearly a decreasing exponential behavior.
文摘Stone matrix asphalt （SMA） is a gap-graded bituminous mixture which can be used in surface layer of high volume pavements. The mixture has higher concen- trations of coarse aggregates, providing strength and rut resistance to the mixture, and higher asphalt content giving durability. There must be a proper stone-to-stone contact between the coarse aggregates of SMA, and hence aggre- gate gradation is an important factor in this mixture. In the current study, two aggregate gradations, with nominal maximum aggregate sizes （NMAS） 16 and 13 mm were adopted to prepare SMA mixtures and their laboratory performances were compared. Polymer-modified bitumen （PMB） was used as the binder material and no stabilising additive was used, since drain down was within permissible limits for both mixtures with PMB. Conventional cylin- drical specimens were prepared in superpave gyratory compactor with bitumen contents 5.0 %, 5.5 %, 6.0 %, 6.5 % and 7.0 % by weight of aggregates, and volumetric and Marshall properties were determined. Tensile strength, behaviour to repeated loading etc. were checked for cylindrical specimens prepared at optimum bitumen con- tent, whereas specially prepared slab specimens were used to check the rutting resistance of SMA mixtures. From the laboratory study, it was observed that, out of the two SMA mixtures, the one with NMAS 16 mm performed better compared to the other. These improved properties may be attributed towards the larger coarse aggregate sizes in the mixture.
文摘Egypt is characterized by wide occurrence of serpentinites, particularly in the central and southern parts of Eastern Desert. There are several cooperate factors that affect the serpentinites used as ornamental stones. These factors involve mineralogical characteristics (including mineral composition and microstructure parameter), physical properties and mechanical properties. Antigorite is an essential serpentinite mineral, with a minor amount of chrysotile. Talc, carbonates (magnesite and dolomite) and tremolite are the main associated minerals. Quality and quantity of associated minerals such as talc and carbonates (dolomite and magnesite) affect the properties of serpentinites used as ornamental stones. Carbonates are resistant to weathering but suffer from acidic cleaning agents in interior use, whereas serpentinites with a high content of talc used on external faces undergo an increase in volume and a consequent rapid degradation. Studied serpentinites are characterized by relatively small grain size with foliated texture, low water absorption, low porosity, and high abrasion resistance. In the samples studied the uniaxial compressive strength (UCS) varies between 89 and 189 MPa, with an average of 152 MPa. According to the classification of Bell (1992), sample No. B8 is very high in strength while the rest high in strength.
