scholarly journals Effects of Randomized Management on the Forest Distribution Patterns of Larix kaempferi Plantation in Xiaolongshan, Gansu Province, China

Forests ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 981
Author(s):  
Junmo Xu ◽  
Gongqiao Zhang ◽  
Zhonghua Zhao ◽  
Yanbo Hu ◽  
Wenzhen Liu ◽  
...  

Patterns of tree distribution are an important attribute of forest structure and directly affect the health and stability of forest ecosystems. This paper studied the effects of forest management on the forest distribution pattern of Larix kaempferi plantations with an aim to improve the quality of the spatial structure of plantations by providing scientific grounds for near-nature distribution pattern adjustment. We set up 15 long-term positioning and monitoring plots of 20 m × 20 m of L. kaempferi plantations in Xiaolongshan, Gansu Province, China, based on the Clark and Evans index, and applied the structure analysis method of the neighboring tree relationship to determine the standard angle of the uniform angle index of regularly distributed plantation forests. The changes in forest distribution patterns were compared before and after randomized management (R1 (dumbbell-shaped random unit), R2 (torch-shaped random unit) and R1:R2 = 1:2 models) and underlayer tending and unmanaged control (CK). The results showed that (1) Under different management modes, the distribution patterns obtained by the Clark and Evans index and the mean values of the uniform angle index were entirely the same; all stand patterns were evenly distributed. (2) Regardless of randomized management or underlayer tending, the number of trees in the even distribution was the largest, accounting for more than 40%. (3) The mean values of the uniform angle index of most stands increased obviously after randomized management, among which the R1 and R2 stands showed an upward trend, while the R1:R2 = 1:2 stands showed a slight decrease. However, the mean values of the uniform angle index of the stands with underlayer management showed a decreasing trend. (4) The proportion of random trees in most stands increased significantly after randomized management, increasing by 1%~19% compared with that before adjustment, while the proportion of random trees in the underlayer tending treatment decreased by 2%~10%. Our results suggest that (1) The method based on the modified uniform angle index standard angle could effectively improve the accuracy of the distribution pattern of individual trees in plantation forests and further improve the accuracy of the overall stand pattern quantitatively. (2) Randomized management significantly increased the proportion of random trees in the stands, which accelerated the evolution of the forest distribution pattern of the L. kaempferi plantation to a random distribution.

2021 ◽  
Author(s):  
Zhixuan Zhang ◽  
Baoyan Shan ◽  
Qikai Lin ◽  
Yanqiu Chen ◽  
Xinwei Yu

Abstract The spatial distribution pattern of buildings is an entry point for controlling the diffusion of pollution particles at an urban spatial structure scale. In this study, we adopted ordinary kriging interpolation and other methods to study the spatial distribution pattern of PM2.5 and constructed urban spatial structure indexes based on building distribution patterns to reveal the influence of building spatial distribution patterns on PM2.5 concentration across the study area and at different elevations. The present study suggests that: (1) Topographic elevation is an important factor influencing the distribution of PM2.5; the correlation coefficient reaches −0.761 and exceeds the 0.001 confidence level. As the elevation increases, the urban spatial structure indexes show significant correlations with PM2.5, and the regularity becomes stronger. (2) The PM2.5 concentration is negatively correlated with the mean and standard deviation of the DEM, the mean and maximum absolute building height, the outdoor activity area, and the average distance between adjacent buildings; and is positively correlated with the sum of the building base area, the building coverage ratio, the space area, the building coverage ratio, the space occupation ratio, and the sum of the building volume. These urban spatial structure indexes are important factors affecting PM2.5 concentration and distribution and should be considered in urban planning. (3) Spatio-temporal differences in PM2.5 concentration and distribution were found at different elevation and time ranges. Indexes, such as the average building height, the average building base area, the sum of the building volume, and the standard deviation of building volume experienced significant changes. Higher PM2.5 concentration yielded a more significant influence of urban spatial structure indexes on PM2.5 distribution. More discrete spatial distributions of PM2.5 yielded weaker correlations between PM2.5 concentrations and the urban spatial structure indexes.


2006 ◽  
Vol 326-328 ◽  
pp. 843-846
Author(s):  
Hyung Joon Kim ◽  
Seung Moo Han

Most ultrasound diagnosing systems for osteoporosis lack diagnostic precision due to the measurement of specific regions of interest (ROI). As well as using the existing ROI measurement method, this study introduced the concept of analyzing the distribution patterns of bone quality. Linear scanning and ultrasound transmission techniques were used to obtain the broadband ultrasound attenuation (BUA) images of the calcaneus. A 13mm-diameter ROI was selected as the position of minimum BUA value locally in the posterior calcaneus. Mean values of BUA and speed of sound (SOS) at the ROI, as well as the osteoporosis index (OI), by their linear combination, were defined. For a more accurate diagnosis of osteoporosis, OI and images of the bone quality distribution of the calcaneus were utilized together. The calcaneus is inhomogeneous and, furthermore, its images are not perpendicular to the direction of the ultrasound beam. Hence, the mean values of BUA and SOS for the entire calcaneus do not have any significant meaning. Accordingly, four image patterns of other OI in the calcaneus were defined in order to increase the correlation between diagnostic parameter and age. The results revealed a higher correlation between the bone quality index and age (r=0.75, p<0.0001), for which the pattern index was reflected on OI, than that (r=0.65, p<0.0001) of OI merely at ROI. This result confirmed the possibility of a new osteoporosis diagnostic method using the BUA distribution images of the entire calcaneus.


2011 ◽  
Vol 27 (4) ◽  
pp. 535-557 ◽  
Author(s):  
Jeong-Im Han ◽  
Jong-Bai Hwang ◽  
Tae-Hwan Choi

The purpose of this study was to evaluate the acquisition of non-contrastive phonetic details of a second language. Reduced vowels in English are realized as a schwa or barred- i depending on their phonological contexts, but Korean has no reduced vowels. Two groups of Korean learners of English who differed according to the experience of residence in English-speaking countries and a group of English native speakers were asked to produce English reduced vowels in word-initial, word-internal and word-final positions. The mean duration ratios, and the mean values and distribution patterns of F1/F2 of the reduced vowels were compared between the three groups, which revealed that Korean learners without residence experience tended to produce each variant of English reduced vowels as the corresponding full vowels, whereas those with experience displayed similar patterns to the natives. The present results suggest that it is possible for second language (L2) learners to learn the statistical properties in L2.


1980 ◽  
Vol 23 (3) ◽  
pp. 630-645 ◽  
Author(s):  
Gerald Zimmermann ◽  
J.A. Scott Kelso ◽  
Larry Lander

High speed cinefluorography was used to track articulatory movements preceding and following full-mouth tooth extraction and alveoloplasty in two subjects. Films also were made of a control subject on two separate days. The purpose of the study was to determine the effects of dramatically altering the structural dimensions of the oral cavity on the kinematic parameters of speech. The results showed that the experimental subjects performed differently pre and postoperatively though the changes were in different directions for the two subjects. Differences in both means and variabilities of kinematic parameters were larger between days for the experimental (operated) subjects than for the control subject. The results for the Control subject also showed significant differences in the mean values of kinematic variables between days though these day-to-day differences could not account for the effects found pre- and postoperatively. The results of the kinematic analysis, particularly the finding that transition time was most stable over the experimental conditions for the operated subjects, are used to speculate about the coordination of normal speech.


1986 ◽  
Vol 55 (01) ◽  
pp. 108-111 ◽  
Author(s):  
M Köhler ◽  
P Hellstern ◽  
C Miyashita ◽  
G von Blohn ◽  
E Wenzel

SummaryThis study was performed to evaluate the influence of different routes of administration on the efficacy of DDAVP treatment. Ten healthy volunteers received DDAVP intranasally (i.n.), subcutaneously (s.c.) and intravenously (i.v.) in a randomized cross-over trial. Factor XII and high molecular weight (HMW)-kininogen levels increased only slightly after DDAVP administration. The mean increase of factor VIII: C was 3.1 (i. v.), 2.3 (s. c.), and 1.3 (i.n.) - fold over baseline. Ristocetin cofactor (von Willebrand factor antigen) increased 3.1 (2.5), 2.0 (2.3) and 1.2 (1.2) - fold over baseline mean values after i.v., s.c. and i.n. DDAVP, respectively. The half-disappearance time of factor VIII and von Willebrand factor (vWF) after DDAVP ranged from five (factor VIII: C) to eight hours (vWF). The mean increase of fibrinolytic activity was more pronounced after i.v. DDAVP. The antidiuretic effect was moderate with no apparent differences between the routes of application. This study provides further evidence that both i.v. and s.c. DDAVP administration result in an appropriate and reliable stimulation of haemostasis. An additional advantage of s. c. administration is its suitability for home treatment.


2018 ◽  
Vol 4 (4) ◽  
pp. 519-522
Author(s):  
Jeyakumar S ◽  
Jagatheesan Alagesan ◽  
T.S. Muthukumar

Background: Frozen shoulder is disorder of the connective tissue that limits the normal Range of motion of the shoulder in diabetes, frozen shoulder is thought to be caused by changes to the collagen in the shoulder joint as a result of long term Hypoglycemia. Mobilization is a therapeutic movement of the joint. The goal is to restore normal joint motion and rhythm. The use of mobilization with movement for peripheral joints was developed by mulligan. This technique combines a sustained application of manual technique “gliding” force to the joint with concurrent physiologic motion of joint, either actively or passively. This study aims to find out the effects of mobilization with movement and end range mobilization in frozen shoulder in Type I diabetics. Materials and Methods: 30 subjects both male and female, suffering with shoulder pain and clinically diagnosed with frozen shoulder was recruited for the study and divided into two groups with 15 patients each based on convenient sampling method. Group A patients received mobilization with movement and Group B patients received end range mobilization for three weeks. The outcome measurements were SPADI, Functional hand to back scale, abduction range of motion using goniometer and VAS. Results: The mean values of all parameters showed significant differences in group A as compared to group B in terms of decreased pain, increased abduction range and other outcome measures. Conclusion: Based on the results it has been concluded that treating the type 1 diabetic patient with frozen shoulder, mobilization with movement exercise shows better results than end range mobilization in reducing pain and increase functional activities and mobility in frozen shoulder.


2019 ◽  
Vol 2 (1) ◽  
pp. 336-346
Author(s):  
Dhamon Oridilla B

Candi Village in Bandungan District is one of the Chili Supply Sub-district for Semarang Regency and surrounding area has agro-climate suitable for the development of various agricultural commodities supported by wide market opportunity, so it is suitable for agricultural business development. The purpose of this research is to identify the distribution pattern of red pepper, to know each value of commodity chains and distribution, to design alternative distribution pattern of red pepper.Population in this research is 88 respondents from 735 of member of chilli farmer in Desa Candi with total area of 150,3 hectare consisting of rice field, moor and yard. Methods of data analyst using quantitative approach is done by using Margin Marketing Analysis. The results include: (1) The pattern of distribution of existing farming business grows naturally in accordance with the developments and needs of the perpetrators, the actors in this pattern are farmers, wholesalers, collectors, wholesalers, retailers, consumers. (2) The value of the red chili commodity chain in this naturally grown pattern often makes pricing more dominant by traders, so farmers receive prices slightly lower than market prices. (3) Some obstacles faced in distributing red peppers are the difficulty of changing the mindset of the community about advanced farming, this is best utilized by market participants (chain of distribution) who are more informed and always keep abreast of market dynamics. Conventional marketing pattern by farmer cause price level accepted by farmer in general relatively smaller compared to price received by trader. Suggestions shorten the chain of distribution patterns, increase the added value of products and improve the bargaining position of farmers and for the government always guide / accompany farmers in getting accurate market information, which can be used as farmers in bargaining, Increased market transparency can act as a trigger for the functioning of a market, improved competition and increased adaptation to meet the needs of supply and opportunity to compete with market prices. Desa Candi di Kabupaten Bandungan adalah salah satu Kecamatan Penyedia Cabai untuk Kabupaten Semarang dan sekitarnya memiliki agroklimat yang cocok untuk pengembangan berbagai komoditas pertanian yang didukung oleh peluang pasar yang luas, sehingga sangat cocok untuk pengembangan bisnis pertanian. Tujuan dari penelitian ini adalah untuk mengidentifikasi pola distribusi cabai merah, untuk mengetahui masing-masing nilai rantai komoditas dan distribusi, untuk merancang alternatif pola distribusi cabai merah. Populasi dalam penelitian ini adalah 88 responden dari 735 anggota petani cabai di Desa Candi dengan total luas 150,3 hektar yang terdiri dari sawah, tegalan dan pekarangan. Metode analis data menggunakan pendekatan kuantitatif dilakukan dengan menggunakan Analisis Pemasaran Margin. Hasil meliputi: (1) Pola distribusi usaha pertanian yang ada tumbuh secara alami sesuai dengan perkembangan dan kebutuhan pelaku, pelaku dalam pola ini adalah petani, pedagang besar, pengumpul, pedagang besar, pedagang besar, pengecer, konsumen. (2) Nilai rantai komoditas cabai merah dalam pola yang dikembangkan secara alami ini sering membuat penetapan harga lebih dominan oleh para pedagang, sehingga petani menerima harga yang sedikit lebih rendah daripada harga pasar. (3) Beberapa kendala yang dihadapi dalam mendistribusikan paprika merah adalah sulitnya mengubah pola pikir masyarakat tentang pertanian maju, hal ini paling baik digunakan oleh pelaku pasar (rantai distribusi) yang lebih banyak informasi dan selalu mengikuti perkembangan dinamika pasar. Pola pemasaran konvensional oleh petani menyebabkan tingkat harga yang diterima petani pada umumnya relatif lebih kecil dibandingkan dengan harga yang diterima pedagang. Saran mempersingkat rantai pola distribusi, meningkatkan nilai tambah produk dan meningkatkan posisi tawar petani dan bagi pemerintah selalu membimbing / menemani petani dalam mendapatkan informasi pasar yang akurat, yang dapat digunakan sebagai petani dalam tawar-menawar, Peningkatan transparansi pasar dapat bertindak sebagai pemicu berfungsinya pasar, meningkatnya kompetisi dan peningkatan adaptasi untuk memenuhi kebutuhan pasokan dan peluang untuk bersaing dengan harga pasar.


1966 ◽  
Vol 53 (2) ◽  
pp. 177-188 ◽  
Author(s):  
P. Lund-Johansen ◽  
T. Thorsen ◽  
K. F. Støa

ABSTRACT A comparison has been made between (A), a relatively simple method for the measurement of aldosterone secretion rate, based on paper chromatography and direct densitometry of the aldosterone spot and (B) a more elaborate isotope derivative method. The mean secretion rate in 9 normal subjects was 112 ± 26 μg per 24 hours (method A) and 135 ± 35 μg per 24 hours (method B). The »secretion rate« in one adrenalectomized subject after the intravenous injection of 250 μg of aldosterone was 230 μg per 24 hours (method A) and 294 μg per 24 hours (method B). There was no significant difference in the mean values, and correlation between the two methods was good (r = 0.80). It is concluded that the densitometric method is suitable for clinical purposes as well as research, being more rapid and less expensive than the isotope derivative method. Method A also measures the urinary excretion of the aldosterone 3-oxo-conjugate, which is of interest in many pathological conditions. The densitometric method is obviously the less sensitive and a prerequisite for its use is an aldosterone secretion of 20—30 μg per 24 hours. Lower values are, however, rare in adults.


1970 ◽  
Vol 64 (2) ◽  
pp. 265-272 ◽  
Author(s):  
A. A. van der Gugten ◽  
M. Sala ◽  
H. G. Kwa

ABSTRACT Eight female and eight male rats were castrated at the age of 8 to 10 weeks. Four spayed and four orchidectomized rats received one oestrone/cholesterol pellet (200 μg oestrone) on the day of operation (day 0), a second pellet on day 11 and a third on day 23. The remaining animals received four oestrone/cholesterol pellets at these times. The fluctuations in the prolactin levels in the circulation induced by the oestrogen challenges in these animals were followed during 31 days by radioimmunoassays performed on days 3, 7, 9, 14, 15, 17, 23, 24, 25, 28 and 31. The results suggested that the homoeostatic mechanism regulating plasma levels of prolactin was capable of withstanding the three time-spaced oestrogen challenges only in the spayed animals receiving the lower doses of oestrogen, since it allowed the mean values of the prolactin levels to remain fairly constant during the first 4 weeks. The levels in this group rose to much higher levels only on day 31. The higher doses of oestrone in the spayed rats and both dose levels of oestrone in the orchidectomized animals apparently resulted in a primary break-down of the homoeostatic mechanism, since the prolactin levels in the animals of these groups rose to much higher levels either on day 7 or on day 9. This was followed by a period during which the prolactin levels appeared to be more or less under control, until a second and probably definitive failure of the homoeostatic mechanism allowed the mean levels to rise sharply again.


2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Izabel Aparecida Soares ◽  
Mauro Sérgio Téo ◽  
Carlise DEBASTIANI ◽  
Suzymeire BARONI ◽  
Vanessa Silva RETUCI

O trabalho teve por objetivo verificar diferenças entre rendimento do concentrado proteico e proteína bruta da folha da mandioca (Manihot esculenta Crantz), obtidos a partir de três variedades comerciais: branca, cascuda e vermelha. As manivas foram plantadas seguindo o delineamento experimental inteiramente casualizado com três repetições. Nas comparações entre as variedades, considerou coletas escalonadas pós-plantio, realizadas aos 12, 14 e 16 meses. O concentrado proteico foi obtido a partir da farinha das folhas inteiras e submetido ao método de termo - coagulação ácido e a proteína bruta pelo método padrão AOAC. Os dados foram submetidos a análise de variância e comparados pelo teste de Tukey - 5% de probabilidade. Os resultados não indicaram diferença significativa entre as médias obtidas para rendimento de concentrado proteico. Para a variável porcentagem de proteína bruta a variedade Branca foi a que apresentou maior valor, com média de 46,25%, seguida pela Cascuda e Vermelha, 44,52% e 37,30%, sucessivamente. Conclui-se que outros estudos devem avaliar condições que possam influenciar no teor de proteína foliar, como clima e solo, e, avaliar os níveis de ácido cianídrico de cada variedade, indicando qual das três é a melhor para a extração do concentrado proteico das folhas. Palavras chaves: Manihot esculenta Crantz, variedades comerciais, concentrado proteico, proteína bruta. ABSTRACT: The study aimed to assess the differences between income protein concentrate, crude protein of cassava leaf (Manihot esculenta Crantz), obtained from three commercial varieties: white, red and cascuda. The cuttings were planted following the completely randomized design with three replications. Comparisons between the varieties considered after planting staggered collections, held on 12, 14 and 16 months. The protein concentrate was obtained from flour of whole sheets and subjected to the term method - acid coagulation and crude protein by AOAC standard method. The data were submitted to ANOVA and Tukey test - 5% probability. The results indicated no significant difference between the mean values obtained for protein concentrate income. For the variable percentage of crude protein White variety showed the highest, with an average of 46.25%, followed by cascuda and Red, 44.52% and 37.30%, successively. We conclude that further studies should evaluate conditions that may affect the leaf protein content, such as climate and soil, and evaluate the hydrocyanic acid levels of each variety, indicating which of the three is the best for the extraction of protein concentrate from leaves Key words: Manihot esculenta Crantz, commercial varieties, protein concentrate, crude protein.


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