Mathematical Modelling of the Fruit-Stone Culture Seeds Calibration Process Using Flat Sieves

The paper provided describes a mathematical model of calibration process of fruit-stone culture seeds of cherry, sweet cherry, cherry-plum, apricot and almond using flat sieves with impact shock ball cleaners oscillating in the horizontal plane. It has been defined that the mathematical expectation of time of knocking out the fruit-stone from the sieve opening T ⌢ \mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown$}}\over T} is the minimum value of ratio of average time of complete ball motion cycle in space under sieve to the probability of knocking out the stone by a ball with the kinetic energy level of 2 Mj. The dependences of energy distribution density of ball on impact on the sieve have been obtained, based on which the intervals of ball cleaner parameters have been determined, i.e. the ball diameter D belongs to the interval 25–35 mm; the space height H under sorting sieve belongs to the interval 1.2D–1.4D mm; the value range for distance between rods t belongs to the interval 0.5D–0.7D mm. Using the method of golden section, the following parameters of ball cleaner were obtained: D = 33 mm, t = 23 mm, H = 40 mm. The parameters obtained provide mathematical expectation of time of knocking out the fruit-stone from the sieve opening T ⌢ \mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown$}}\over T} = 0.03 s. Consequently, the average ball velocity v ⌢ \mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown$}}\over v} is = 0.4 m∙s-1, and the average ball path is L ⌢ \mathord{\buildrel{\lower3pt\hbox{$\scriptscriptstyle\frown$}}\over L} = 0.006 m.

Traces of Late Bronze and Early Iron Age Mongolian Horse Mitochondrial Lineages in Modern Populations

The Mongolian horse is one of the most ancient and relatively unmanaged horse breeds. The population history of the Mongolian horse remains poorly understood due to a lack of information on ancient and modern DNA. Here, we report nearly complete mitochondrial genome data obtained from five ancient Mongolian horse samples of the Khereksur and Deer Stone culture (late 2nd to 1st third of the 1st millennium BC) and one ancient horse specimen from the Xiongnu culture (1st century BC to 1st century AD) using target enrichment and high-throughput sequencing methods. Phylogenetic analysis involving ancient, historical, and modern mitogenomes of horses from Mongolia and other regions showed the presence of three mitochondrial haplogroups in the ancient Mongolian horse populations studied here and similar haplotype composition of ancient and modern horse populations of Mongolia. Our results revealed genetic continuity between the Mongolian horse populations of the Khereksur and Deer Stone culture and those of the Xiongnu culture owing to the presence of related mitotypes. Besides, we report close phylogenetic relationships between haplotypes of the Khereksur and Deer Stone horses and the horses of indigenous breeds of the Middle East (Caspian and Iranian), China (Naqu, Yunnan, and Jinjiang), and Italy (Giara) as well as genetic similarity between the Xiongnu Mongolian horses and those of the most ancient breeds of the Middle East (Arabian) and Central Asia (Akhal-Teke). Despite all the migrations of the Mongolian peoples over the past 3000 years, mitochondrial haplogroup composition of Mongolian horse populations remains almost unchanged.

A comparison of pre-operative urine culture with intra-operative stone culture: a prospective observational study

Background It is well known that urinary calculi are associated with urinary tract infections. Post-operative sepsis is one of the major complications after various endourological procedures for stone surgeries. These episodes of sepsis occur even in negative urine cultures. Stones have been found to harbour bacteria which on fragmentation causes bacteremia and sepsis. Thus, usual practice of pre-operative urine culture cannot truly predict the occurrence of post-operative sepsis. It also seems logical that intra-operative stone cultures could guide us for early management of such episodes of sepsis. The purpose of this study was to determine if there exists any association between urine and stone cultures in patients undergoing endourological stone surgeries. Methods This is a prospective comparative observational study, in patients undergoing endoscopic procedures for calculus in urinary tract. Mid-stream urine cultures were obtained 3 to 5 days prior to surgery and crushed stone culture during the surgery. Comparison was then made between the two with respect to positivity, location of calculus and bacterial flora. Results A total of 122 cases of urolithiasis were included, in which 30 (24.59%) cases had a positive urine culture, whereas 62 (50.82%) patients were positive for stone culture. This significant difference was maintained only in renal stones on subset analysis (p value < 0.0001). Both cultures were positive in only 15% of cases, and bacteriological analysis showed same organism in just 6.5% of cases. In our study, sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of urine culture against the stone culture were 29.03%, 80%, 60%, 52.17% and 54.09%. Conclusion The results of our study suggests that pre-operative urine cultures have a poor predictive value and accuracy for infective organism in the renal stone. Therefore, stone culture should be included in routine protocols during renal endourologic surgery for stones.

Study of Bacterial Aetiogenicity of Pigment Gall Stones by Culture of Nidus of Calculus and correlation between Stone Culture and Bile Culture

Background: Calculus disease of biliary tract is a major public health problem in north Kashmir and pigment gall stones form a significant portion of gall stones in our region. In this study we prospectively studied 84 cases of pigment gall stones to examine the role of bacteria in the formation of these stones. Objective: To study the bacterial aetiology of pigment gall stones. Methods: A hospital based prospective study of 84 consecutive cases of pigment gall stones was done from December 2012 to November 2019 and the results of stone culture and bile culture were statistically analysed. Informed consent was obtained from all the patients in the study group. Results: A total of 84 cases studied included 32 (38.09%) male patients and 52(61.91%) females patients. The median age was 48.5 years and mean age was 46.2 years. Of 84 patients, 21(25.00%) had black pigment stones and 63 (75.00%) had brown pigment stones. 61 (72.62%) patients presented with biliary colic and 24(28.57%) patients had chronic cholecystitis . Bile culture was positive in 46 (54.76%) patients and stone culture was positive in 70(83.33%) patients. Conlusion: A strong association was observed between stone culture and bile culture results (showing similar beta-glucronidase producing bacteria) and pigment stone formation.

The study of rod-shaped TiO2 composite material in the protection of stone cultural relics

TiO2 has many advantages, such as UV resistance, thermal stability, and antibacterial; the attention toward TiO2 composite materials (TCMs) is rapidly increasing in the protection of stone culture relics. An innovative rod-shaped TCM was synthesized in this study. The structure and morphology of TCM were studied by X-ray diffraction and scanning electron microscopy. The acid resistance, weather resistance, hydrophilicity, and photocatalytic performance of TCM had been investigated. The experimental results indicated that TCM has good protection effects. The stone sample treated with TCM has stronger acid resistance and weather resistance, better hydrophilicity, and more excellent photocatalytic activity compared with the untreated stone. More importantly, the stone treated with TCM has better acid resistance and weather resistance than that treated with normal shaped TiO2 materials of the previous study. This work describes an effective way to protect stone cultural relics.